In 2016, 8.1% of elderly population in Hong Kong resided in non-domestic households (ie, residential care homes for the elderly [RCHEs], hospitals and penal institutions, etc).1 Residential care homes for the elderly are a heterogeneous group of institutions that provide varying levels of care for elderly people, who, for personal, social, health, or other reasons, can no longer live alone or with their families.

There is a mix of government-subvented, self-financed, and privately run RCHEs in Hong Kong. All RCHEs must be licensed under the Residential Care Homes (Elderly Persons) Ordinance. The RCHEs operate according to the code of practice (COP)2 issued by the licensing authority. The COP sets out guidelines, principles, procedures, and standards for the operation and management of RCHEs. A chapter in the COP is devoted to infection control, requiring the RCHE’s operator to designate an infection control officer (ICO). The ICO must coordinate and implement infection control measures within the home according to the infection control guideline issued by the Centre for Health Protection of the Department of Health.3 Operators of RCHEs are required to report specific infectious disease cases and outbreaks to the authorities.

Eighteen visiting health teams (VHTs) are established under the Elderly Health Service of the Department of Health in Hong Kong. Comprising 47 nurses, the teams reach out into the community and residential care settings to conduct health promotion activities for the elderly people, and carers of elderly people, aiming to increase the health awareness and the self-care ability of elderly people, and to enhance the quality of caregiving.

The first on-site assessment covering all RCHEs in Hong Kong on infection control performance was conducted by VHTs between August and October 2003 as an enhanced measure in response to the severe acute respiratory syndrome (SARS) outbreak. Since then, annual assessments have been conducted by VHTs to assess and monitor the effectiveness of infection control measures and to identify the training needs of healthcare staff working in RCHEs, so as to plan for training activities for the following year. Assessment results are shared with relevant stakeholders, including the licensing authority and the community geriatric teams of public hospitals which provide outreach personal medical care to residents of RCHEs. Feedback is also provided to RCHE staff, to increase their alertness and encourage improvements.

This study aimed to review the 10-year trend in infection control practices in RCHEs in Hong Kong, based on results of the annual VHT assessments conducted from 2005 to 2014.

Assessment of all RCHE facilities, and the infection control knowledge and skills of staff are conducted annually via structured questionnaires and observational checklists.

The annual surveys cover all RCHEs in Hong Kong from 2005 to 2014, based on the lists maintained by the licensing authority.4 The coverage rate was 98.5% to 100% from 2005 to 2014. A few RCHEs were not covered because they were either non-operating (under renovation or recently closed) or refused the VHT service. These RCHEs were excluded from analysis.

The surveys were conducted from August to October each year, based on an assessment protocol developed by doctors and nurses of the VHTs, and with reference to the COP,2 the prevailing “Guidelines on Prevention of Communicable Diseases in Residential Care Home for the Elderly”3 and overseas guidelines on infection control practice.5 6 7 Resident demographics, staff profiles, information on environment and facilities related to infection control, and knowledge and skills of the ICO and other staff were collected in the surveys. The assessments were divided into four parts:

Part I: The characteristics and profiles of residents and staff of the RCHEs, including the subjective training needs of staff, were collected through a self-administered questionnaire (online supplementary Appendix) completed by the person-in-charge of the RCHE, prior to the site visit by the VHT.

Part II: The environmental conditions and facilities related to infection control in RCHEs were assessed by a VHT nurse during the site visit.

Part III: The health monitoring and record keeping practices in RCHEs were assessed during the site visit.

Part IV: The knowledge and skills on infection control of staff in RCHEs were assessed in face-to-face interviews during the site visit. The ICO (or other staff, depending on the topic being assessed) of each RCHE was assessed. An additional member of staff (either a health worker or care worker) was also selected at random for assessment on hand washing technique.

After the assessments, data were either double-entered or double-checked by two separate colleagues. In addition, 10% of the questionnaires were audited by an independent colleague, who rechecked all questionnaires if the error rate detected was greater than 0.5% of data fields. Descriptive statistics on the characteristics of the residents and the health/personal care staff were tabulated. Categorical data were analysed by either Chi squared test or Fisher’s exact test while trend analysis was conducted by linear regression. A linear trend is reported as significant when the slope of the regression line is statistically different from zero. All analyses were conducted using SPSS (Windows version 24.0; IBM Corp, Armonk [NY], United States). This report was prepared following the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement.8

The majority of RCHEs (ranging from 73.9% to 75.7%, between 2005 and 2014) were commercially operated RCHEs (“private RCHEs”). The remaining 24.3% to 26.1% were “non-private RCHEs”, comprising those that received subsidies or subventions from the government and those that were non–profit making and self-financing in nature.9

The age profile of the residents in RCHEs from 2005 to 2014 is shown in the Figure. An apparent ageing trend is observed with the proportion of RCHE residents aged ≥85 years rising from 40.0% (23 718) in 2005 to 50.2% (31 149) in 2014 (P=0.002).

Table 1 shows the percentage of residents with special care needs from 2005 to 2014. The proportion of residents with dementia increased from 22.3% in 2005 to 32.6% in 2014 (P<0.001). The percentage of residents with a long-term indwelling urinary catheter increased from 3.4% in 2005 to 5.0% in 2014 (P<0.001), representing a 47% increase in the number of patients with a long-term indwelling urinary catheter.

The resident-to-staff ratios in RCHEs from 2005 to 2014 are shown in Table 2. The major types of staff in RCHEs in Hong Kong are professionally qualified nurses (including registered nurses and enrolled nurses registered under the Nursing Council of Hong Kong), health workers who have completed basic training recognised by the licensing authority, care workers who have not received any official training, and other staff including allied health and supporting staff. There were no significant changes in overall resident-to-staff ratio over the study period. For nurses and health workers, the overall manpower ratios improved from 30:1 and 27:1 in 2005 to 23:1 and 17:1 in 2014, respectively (both P<0.001). Increases in numbers of full-time and part-time nurses and health workers contributed to the improvements in these ratios.

There was an observable difference in terms of the number of nurses between private RCHEs and non-private RCHEs. In 2014, the resident-to-nurse ratio was 58:1 in private RCHEs compared with 11:1 in non-private RCHEs. In fact, the majority of private RCHEs (70.9%) did not employ any nursing staff. In contrast, only 3.8% of non-private RCHEs did not have any nursing staff. Only 18.5% of private RCHEs had assigned nurses as ICOs, whereas the percentage was 93.0% in non-private RCHEs. The rest of the RCHEs appointed health workers as ICOs.

The RCHEs are collective living places where communicable diseases can easily spread through contact with the environment. Therefore, it is essential for RCHEs to be equipped with proper facilities to prevent outbreaks. After years of promotion, the proportion of RCHEs with alcohol hand rub increased significantly from 25.4% in 2006 to 99.2% in 2014 (P=0.008), as shown in Table 3. Nevertheless, further examination of a selected bottle of alcohol hand rub at each of the RCHEs revealed that, in 2014, only 92.4% of RCHEs had alcohol hand rub that had proper concentrations and were within the expiry dates. Although this was an improvement from 64.1% in 2008, a difference in performance was observed in 2014, with only 90.7% of private RCHEs having proper alcohol hand rub, compared with 97.3% of non-private RCHEs (P=0.003).

According to the COP for RCHEs,2 an isolation facility is a basic requirement for an RCHE and is defined as “a designated area or room with good ventilation, adequate space for equipment for proper disposal of personal and clinical wastes, and basic hand hygiene and hand-drying facilities as well as electric call bell.” The proportion of RCHEs equipped with a designated room as an isolation area for fever cases ranged from 73.6% to 80.0% between 2005 and 2014. No obvious trend was observed. In 2014, 19.9% and 0.8% of RCHEs were still only able to provide fixed boards of either three-quarters or half the height of the room, respectively, as partitions for the isolation area instead of providing separate rooms (Table 3). More non-private than private RCHEs were able to designate a separate room for isolation in 2014 (90.3% vs 73.3%, P<0.05). However, of the rooms designated as isolation areas, 1.5% in non-private RCHEs and 5.3% in private RCHEs were found to be occupied by residents without the need for isolation, or used for storage.

For contact tracing and outbreak investigation, a proper record system is essential. Only 60.3% of all RCHEs kept proper visitors’ record in 2005, increasing to 92.1% in 2014. There were also moderate improvements in the maintenance of sick leave records for staff, fever records for residents, and training records on infection control for staff, as shown in Table 3. However, a statistically significant trend could not be identified.

The ICO’s skill at hand washing, wearing and removing of personal protective equipment, and preparing bleach solution for environmental disinfection were tested in each RCHE. In addition to assessing the ICO, a health worker or care worker was also selected at random for hand washing technique auditing. The proportion of ICOs with proper hand washing technique increased from 86.7% in 2005 to 96.9% in 2014, although a statistically significant trend was not observed (P=0.14). However, an improvement trend was observed for non-ICO health/care workers from 79.2% in 2006 to 91.5% in 2014 (P=0.02) [Table 3]. The proportion of ICOs with proper skills on wearing and removing of personal protective equipment ranged from 80.7% to 88.9% between years 2006 and 2014 (P=0.27). The proportion of ICOs who were able to prepare bleach solution with the proper concentration showed an improving trend from 71.5% in 2005 to 92.2% in 2014 (P=0.002).

Infectious disease outbreaks are major concerns for RCHEs as they often lead to significant morbidity and mortality. Local data on infection control practices among RCHEs are limited. The current study is the first institution-based serial survey on the trend of infection control practices among RCHEs.

Residents of RCHEs are often functionally impaired, putting them at higher risk of infection.10 Our results show that the proportion of RCHE residents aged ≥85 years is increasing (Fig). This is expected to result in increased prevalence of co-morbidities and functional impairment, leading to further infection control challenges.

There have been improvements in infection control practices among RCHEs over the study period from 2005 to 2014, in terms of manpower, facilities, practices, knowledge, and skills. The improvement was most obvious in terms of manpower and facilities. More nurses and health workers were recruited into RCHEs, and common areas equipped with alcohol hand rub. There was also a 10.2% improvement in hand washing skills and a 5.9% improvement on skills of wearing and removing of personal protective equipment among ICOs during the study period (Table 3). Possible contributory factors to such improvements may include the overall increased level of awareness on the importance of infection control, increased availability of manpower11 12 13 and financial resources, and improved access to infection control training programmes.

Despite the improvements in infection control, there are some areas of concern that are worth noting.

First, there was a sharp initial increase in the number of RCHEs that had separate rooms as isolation areas in 2004. This was likely an enhancement measure in response to the SARS outbreak in 2003. However, the proportion of RCHEs with separate isolation rooms has remained stable at around 70% since then, despite ongoing training and education. Possible explanations for this plateau include lack of space, other competing demands, and other resourcing issues.

A similar plateau effect was also observed for knowledge and skills on infection control measures. The RCHE staff’s knowledge on the assessment items significantly improved (to near 90% for most topics), then showed little further improvement.

Non-private RCHEs consistently performed better than private RCHEs, especially in terms of nursing manpower, availability of proper isolation areas, and availability of effective alcohol hand rub. There is a fundamental funding difference between private and non-private RCHEs. In addition to complying with statutory requirements, government subvented RCHEs or those providing subsidised places (eg, RCHEs participating in bought place schemes) are also required to meet quality standards set out in the service contracts with the government. However, private RCHEs not participating in such schemes are only required to comply with the minimum statutory standards, such that service quality among private RCHEs remains variable.14

Moreover, the high staff turnover rate in the private sector may also explain why the performance of infection control in private RCHEs still lags behind that of non-private RCHEs, because knowledge and skills are not retained when trained care workers leave.15

There are several main limitations to our study. First, although RCHE staff have attained a generally adequate level of knowledge and skills on infection control, the implementation or the extent of adoption of these skills in daily practice could not be ascertained by our assessments which took the form of knowledge and skill tests rather than covert observation of real practice. In addition, the achieved results might not be representative, because the pre-scheduling allowed ample lead time for the staff of the RCHEs to prepare for the assessment. Unannounced visits and covert observation might provide a more accurate assessment of staff skill levels and the extent of application of such skills in daily practice, although covert observation itself may pose other practical challenges.16

Second, it was not feasible for us to interview all staff during our site visits, because the RCHEs must maintain routine service for residents. During site visits, we assessed the knowledge and practice of only the ICO and one additional health or care worker. The performance of these two selected workers might not be representative of all staff of the RCHE.

Third, to enhance comparability of assessment results, most questions asked and skills tested were similar between years. Thus, the assessment content might become predictable as the assessments were repeated annually. This might have led to survey fatigue and inability to capture true performance.

With an increasingly frail and ageing cohort of residents, RCHEs are expected to face a growing risk of infectious disease outbreaks in the coming decades, especially those involving multidrug-resistant organisms. Other than general infection control measures already adopted by the RCHEs, having a stable and well-trained workforce will become an increasingly important factor in determining the success of RCHEs in combating infectious diseases, especially as the number of elderly residents with special care needs (such as those with indwelling urinary catheters or on nasogastric feeding) is rising. Manpower planning, development, and staff retention will remain a challenge for infection control.

Moreover, as knowledge and skills on infection control have stopped improving, training on infection control should emphasise encouraging sustainability of vigilant practices. Measures including self-auditing on infection control should be considered, to encourage RCHE staff to monitor their own infection control performance on a regular basis, between annual external assessments.

This is the first territory-wide report on trends in infection control performance in RCHEs in Hong Kong. Data collected enabled us to understand the strengths and limitations in RCHEs on infection control, thus allowing stakeholders to design more targeted infection control training programmes.

Knowledge and skills on infection control have reached an adequate level and remained stable. Future infection control training should aim to support sustained compliance with proper practice, through introduction of elements such as self-audits.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

Concept or design: GCY Wong, T Ng, T Li.
Acquisition of data: GCY Wong.
Analysis or interpretation of data: GCY Wong.
Drafting of the article: GCY Wong.
Critical revision for important intellectual content: T Ng, T Li.

The authors have disclosed no conflict of interest.

The report was funded by the Department of Health, Hong Kong.

A waiver for ethical review was endorsed by the Ethics Committee of the Department of Health, Hong Kong.

1. Census and Statistics Department, Hong Kong SAR Government. 2016 Population By-census. Thematic report: older persons. Available from: https://www.bycensus2016.gov.hk/data/16BC_Older_persons_report.pdf. Accessed 8 Jan 2019.

2. Social Welfare Department, Hong Kong SAR Government. Code of practice for residential care homes (elderly persons). Available from: http://www.swd.gov.hk/doc/LORCHE/CodeofPractice_E_201303_20150313R3.pdf. Accessed 8 Jan 2019.

3. Department of Health, Hong Kong SAR Government. Guidelines on prevention of communicable diseases in residential care home for the elderly (3rd edition). Available from: https://www.chp.gov.hk/files/pdf/guidelines_on_prevention_of_communicable_diseases_in_rche_eng.pdf. Accessed 8 Jan 2019.

4. Social Welfare Department, Hong Kong SAR Government. List of residential care homes. Available from: https://www.swd.gov.hk/en/index/site_pubsvc/page_elderly/sub_residentia/id_listofresi/. Accessed 8 Jan 2019.

5. World Health Organization. WHO guidelines on hand hygiene in health care. Available from: http://apps.who.int/iris/bitstream/handle/10665/44102/9789241597906_eng.pdf?sequence=1. Accessed 8 Jan 2019.

6. Audit tools for monitoring infection control guidelines within the community setting. Bathgate, UK: Infection Control Nurses Association; 2005.

7. Routine practices and additional precautions in all health care settings. Canada: Provincial Infectious Diseases Advisory Committee. Ministry of Health and Long-Term Care; 2009.

8. von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP; STROBE Initiative. The strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies. PLoS Med 2007;4:e296. Crossref

9. Social Welfare Department, Hong Kong SAR Government. SWD elderly information website. Type of residential care homes. Available from: https://www.elderlyinfo.swd.gov.hk/en/rches_natures.html. Accessed 8 Jan 2019.

10. Büla CJ, Ghilardi G, Wietlisbach V, Petignat C, Francioli P. Infections and functional impairment in nursing home residents: a reciprocal relationship. J Am Geriatr Soc 2004;52:700-6. Crossref

11. Castle NG, Engberg J. The influence of staffing characteristics on quality of care in nursing homes. Health Serv Res 2007;42:1822-47. Crossref

12. Bostick JE, Rantz MJ, Flesner MK, Riggs CJ. Systematic review of studies of staffing and quality in nursing homes. J Am Med Dir Assoc 2006;7:366-76. Crossref

13. Bowers BJ, Esmond S, Jacobson N. The relationship between staffing and quality in long-term care: exploring the views of nurse aides. J Nurs Care Qual 2000;14:55-64. Crossref

14. Hong Kong SAR Government’s response to a question raised by a Legislative Councillor on 11 January 2017. Available from: https://www.info.gov.hk/gia/general/201701/11/P2017011100501.htm. Accessed 28 Jan 2019.

15. Research Brief Issue No. 1 2015-2016, Research Office, Legislative Council Secretariat, Hong Kong. Available from: https://www.legco.gov.hk/research-publications/english/1516rb01-challenges-of-population-ageing-20151215-e.pdf. Accessed 8 Jan 2019.

16. Petticrew M, Semple S, Hilton S, et al. Covert observation in practice: Lessons from the evaluation of the prohibition of smoking in public places in Scotland. BMC Public Health 2007;7:204. Crossref

With an age-standardised incidence rate of 24.2 per 100 000 population, gastric cancer is a major clinical entity in Eastern Asia.1 Operative resection remains the only curative treatment available. Over the years, advances in minimally invasive surgery have caused a paradigm shift towards laparoscopic gastrectomy (LG), with high-quality evidence from both the East and West demonstrating a satisfactory safety profile and enhanced postoperative recovery related to reduction of surgical trauma.2 3

However, one major concern regarding LG is its oncologic equivalency compared with the open technique, as LG requires adequate lymphadenectomy and involves a steep learning curve. Several overseas studies have shown comparable lymph node harvest and survival data2 3 4 but are limited by either short follow-up periods or being published by major centres in Korea or Japan, where extensive experience is available. Whether or not these results are reproducible in smaller regional centres is unknown, especially in Hong Kong, where no comparative studies concerning LG for gastric cancer exist in the literature. It has been suggested that a case volume of approximately 50 to 60 LGs is required to achieve proficiency, with demonstrable decreases in blood loss, conversion rate, and hospital length of stay (LOS) with increasing experience.5 Furthermore, most of these data were based on operations for early gastric cancer in patients selected according to strict criteria. In advanced cases requiring extensive lymphadenectomy, evidence is still emerging, and the learning curve may be steeper.

At our regional surgical centre in Hong Kong, LG is currently the first-line modality in the absence of contra-indications. We aimed to perform a matched retrospective cohort study of laparoscopic versus open gastrectomy for resectable advanced gastric adenocarcinoma of all sites, comparing intra- and peri-operative characteristics, oncological clearance, and long-term outcomes including survival and recurrence.

A prospective gastric cancer database was maintained at the Department of Surgery, Queen Elizabeth Hospital. From January 2009 to March 2017, 221 patients who underwent curative gastrectomy for advanced gastric adenocarcinoma (ie, clinical T2 to T4 lesions of all sites) were identified. Clinical T1 lesions (n=23); cases with pathologies other than adenocarcinoma, like high-grade dysplasia (n=1); squamous cell carcinoma (n=2); neuroendocrine tumours (n=4); gastrointestinal stromal tumours (n=3); and cases involving conversion of approach (n=6) were excluded. A total of 54 patients operated via a totally laparoscopic approach were identified and matched with 167 patients who underwent the same operation via an open approach during the same 8-year period. The case ratio between the laparoscopic and open groups was 1:3.09. Patients from both groups were matched in terms of age, sex, American Society of Anesthesiologists (ASA) class, tumour location, morphology, and clinical stage. Follow-up was performed on all subjects at the Upper Gastrointestinal Surgical Specialist Outpatient Clinic of our hospital at 3-month intervals up to 2 years postoperation and every 6 months thereafter.

All 54 LG and 167 open operations were performed by two experienced upper gastrointestinal surgeons with experience of more than 100 gastrectomy operations each. The choice of approach was decided by the attending surgeon. All subjects underwent radical gastrectomy with D2 lymph node dissection as per the guidelines of the Japanese Gastric Cancer Association6; that is, in addition to the perigastric nodes, a second tier of lymph nodes along the celiac axis branches were removed. Distal subtotal, proximal, or total gastrectomy was selected depending on tumour location and macroscopic characteristics. Splenectomy or distal pancreatectomy was performed if there was direct invasion with the possibility of en bloc complete resection.

Under general anaesthesia, with the patient in supine split leg position, LG was performed with the surgeon operating on either side of the patient and a camera assistant in the middle. Pneumoperitoneum was created via the open Hasson technique at a pressure of 12 mm Hg, followed by insertion of a 12-mm infra-umbilical camera port, then one 12-mm and one 5-mm working port in each upper quadrant of the abdomen for a total of five ports.

Distal and total gastrectomy accounted for 98% of all LGs performed. Hence, our discussion of technique shall focus on them. For total gastrectomy, entry to the lesser sac was obtained via dissection of the avascular plane between the greater omentum and transverse mesocolon. The gastrocolic ligament was divided proximally and then distally towards the pylorus using a laparoscopic energy device. The right gastroepiploic vessels were doubly clipped and divided at their origin. Then, dissection of the hepatoduodenal ligament was performed, with division of the right gastric artery and transection of the duodenum with a linear stapler. The dissection continued towards the gastroesophageal junction along the lesser curvature. Along with that dissection, simultaneous D1 lymphadenectomy of the perigastric nodes was performed. Then, D2 lymphadenectomy was performed, with removal of the common hepatic artery (Station 8) nodes. The root of the left gastric artery was doubly clipped and then divided, followed by dissection of celiac trunk (Station 9) and left gastric artery (Station 7) nodes. The splenic artery lymph nodes (Station 11) and hilar nodes (Station 10) were excised together with the surrounding fatty connective tissues. During distal gastrectomy, the left cardia (Station 2), greater curvature (Station 4sa), splenic hilum (Station 10), and distal splenic artery (Station 11d) nodes were left intact.

After adequate mobilisation, the stomach or distal oesophagus was divided using a linear stapler with several centimetres of margin, and the surgical specimen was placed in an endobag for later retrieval. Following total gastrectomy, oesophagojejunal anastomoses were fashioned end-to-side using a circular stapler and a transoral anvil device, whereas distal gastrectomy reconstruction was performed by either Roux-en-Y gastrojejunostomy or delta-shaped Billroth I anastomosis. Side-to-side oesophagogastrostomy was utilised in cases of proximal gastrectomy.

Open gastrectomies followed standard procedures from the surgical literature and were characterised by a wider range of reconstructive techniques in our study.

All clinical data originated from the patients’ electronic and handwritten medical records and were recorded into the prospective gastric cancer database by one principal investigator. Recall and observer bias were addressed by this approach. Selection bias was minimised by matching and controlling for covariates in the outcome analyses. Our pathological staging followed that of the American Joint Committee on Cancer (AJCC) for gastric cancer. Complications were graded from 1 to 5 according to the Clavien-Dindo classification, with 1 to 2 being minor complications and 3 to 5 being major complications. We defined 30-day mortality as any death, inside or outside of the hospital, within 30 days of surgery. Recurrences were documented as either local or distant, depending on the first recognised disease site. We designated survival time as the time from the date of the operation until death or the last available follow-up (if the patient did not experience an event of interest).

All statistical analyses were performed using the SPSS (Windows version 22.0; IBM Corp, Armonk [NY], United States). Frequency matching was employed to ensure that the laparoscopic and open groups had equal distributions of age, sex, ASA class, tumour location, morphology, and clinical stage. Appropriate univariate analyses like the Mann-Whitney U test were selected to examine continuous variables, whereas Chi squared and Fisher’s exact tests were run for dichotomous and categorical variables, respectively. Operative outcomes like blood loss, operating time (OT), type of operation, complications, 30-day mortality, LOS, and oncologic outcomes such as margin clearance, pathological stage, lymph node yield, adjuvant treatment, survival time, and disease recurrence were compared. Survival probabilities were estimated using the Kaplan-Meier method and compared using stratified log-rank tests. All P values were based on two-tailed statistical analyses with P<0.05 as the threshold for statistical significance. All percentages were rounded off to nearest integer.

A total of 221 matched patients were evaluated. The median age at the time of operation was 67 years (range, 23-80 years), with the majority of patients (145, 66%) being male. Most patients (62%) were in the ASA 2 category (ie, mild systemic disease without functional limitation).

In order of descending frequency, 42% of the tumours were located in the antrum, followed by the gastric body (30%) and cardia/fundus (24%). All 221 patients had advanced gastric cancer according to the AJCC clinical staging. Clinical T3 and T2 lesions accounted for 51% and 37% of cases, respectively, and the remaining 12% were category T4. Macroscopically, 70% of the tumours were of Bormann types 3 or 4; only 30% were types 1 or 2 (ie, polypoid or ulcerative with clear margins). Of all the investigated subjects, 56% had N1 disease on imaging, while the rest (44%) were negative. No subject had clinically detectable metastases.

No statistically significant differences were demonstrated in any of the six matching parameters between the laparoscopic and open patient groups. The details of the subjects’ demographic variables are charted in Table 1.

All 221 patients underwent D2 lymphadenectomy. The frequency of operation type was comparable between distal and total gastrectomy (43% and 53%, respectively). Distal pancreatectomy was performed in six (4%) subjects in the open group only, with no statistically significant difference between groups (P=0.340). Splenectomy was performed in 10 (6%) versus 0 subjects in the open and laparoscopic groups, respectively, and this difference was not statistically significant (P=0.124). The history of laparotomy was comparable between groups (7% vs 11% for the laparoscopic and open groups, respectively, P=0.606).

The laparoscopic group had shorter median OT (321 vs 365 min, P=0.003) and less intra-operative blood loss (150 vs 275 mL, P=0.018). Operative complications were observed in 41% and 51% of laparoscopic and open cases, respectively; this trend seemed to favour the laparoscopic group but failed to reach statistical significance (P=0.210). Subgroup analyses showed that fewer minor complications were demonstrated in the laparoscopic group (13% vs 40%, P<0.001). One case of open distal gastrectomy and laparoscopic total gastrectomy each accounted for the 30-day mortality among all subjects. Both were older adults in their 70s who developed sudden cardiac arrest and cerebrovascular accident, respectively, in the days after operation. The median postoperative LOS was 9 and 11 days, significantly shorter in the laparoscopic group (P=0.011).

Tumour location and clinical stage were comparable between groups, as they were matching variables. All patients had adenocarcinoma. Margin clearance was satisfactory, ranging from 96% to 98% in the laparoscopic group and 94% to 96% in the open group, and the P value showed no significant between-group difference in this metric. Over half (57%) of the patients were in pathological stage III, with no significant difference in staging between the groups. Interestingly, the median number of lymph nodes harvested was higher in the laparoscopic group at 37 (range, 7-77) compared with 26 (range, 3-95) in the open group (P<0.001). Adjuvant treatment was prescribed in 41% (22 of 54) of laparoscopic group patients versus 28% (47 of 167) of open group patients, but this difference did not reach statistical significance (P=0.093).

The mean postoperative follow-up duration was 33 months (laparoscopic group: 25 months, open group: 35 months). Disease recurrence was observed in 9% and 28% of laparoscopic and open group patients, respectively, with a statistically significant between-group difference (P=0.005). During the entire follow-up period, death occurred in 19 out of 54 laparoscopic group (35%) and 97 out of 167 open group (58%) patients. Median disease-free survival (DFS) was 46.9 months and 31.7 months, and median overall survival (OS) was 46.9 months and 34.9 months, for the laparoscopic and open groups, respectively. Using a 60-month cut-off, the estimated 5-year DFS and OS were both 47% for the laparoscopic group and 39% for the open group (P=0.210 and P=0.233, respectively). The details of the operative, pathological, and oncological outcomes are charted in Table 2, and the Kaplan-Meier plots for DFS and OS are shown in Figures 1 and 2, respectively.

Laparoscopic gastrectomy has markedly matured since its inception by Kitano et al7 in 1994. In early gastric cancer, high-quality evidence including meta-analyses has demonstrated the equivalence of laparoscopic distal gastrectomy and open surgery. Early postoperative benefits include less blood loss, fewer complications, and shorter LOS with comparable mortality. However, lengthier operations and smaller lymph node yield remain issues in the laparoscopic approach.8 Technical difficulties in anastomosis and laparoscopic lymph node dissection have resulted in poorer translation of these results to total gastrectomies, and such application is often practised only in expert centres with exceptional case volume.9 Similar controversies also exist in the field of advanced gastric cancer, where adequate lymphadenectomy is of the utmost importance. Acceptable short-term outcomes have been reported only in studies that incorporated experienced surgeons, with the technique’s long-term safety still unknown.10 11 12

As such, the safety and oncologic efficacy of LG are influenced to a large extent by regional incidence and the case volume of individual centres. With an age-standardised incidence rate of 9.1 per 100 000 population in Hong Kong, compared with 41.8 per 100 000 population in Korea and 24.2 per 100 000 population overall in Eastern Asia, gastric carcinoma is far from the top in terms of cancer incidence ranking.1 13 While this low age-standardised incidence rate may be partially explained by the absence of population-wide screening, this lack of screening also implies that a higher proportion of patients will present with advanced disease. These two points, together with the absence of studies evaluating LG in the local literature, mark the importance of our study in evaluating the efficacy and safety of such procedures in treatment of advanced gastric cancer in Hong Kong.

Queen Elizabeth Hospital, the largest acute hospital in Hong Kong and a tertiary surgical referral centre, has a significant case volume and a patient pool that is representative of the local population. Through this study, we aimed to document the local Hong Kong experience, comparing and contrasting results from Hong Kong with those from overseas expert centres.

In accordance with other major studies, we demonstrated that LG was associated with less blood loss, fewer minor complications, and shorter LOS while achieving similar overall levels of complications and operative mortality to open surgery. The lesser degrees of pain, blood loss, ileus, and surgical site infections associated with laparotomy than open surgery are well-investigated benefits of the laparoscopic approach, and this explains the scarcity of minor complications.3 8 Median postoperative LOS was 2 days shorter after LG than open surgery, a small but statistically significant difference. No local data on average post-gastrectomy LOS exist, but our results are comparable with an LOS of 11 days (range, 8-12.5 days) observed in the United Kingdom.14 The small difference in LOS between the laparoscopic and open groups may be partially explained by the fact that, compared with Western counterparts, local Chinese patients prefer in-patient care over community care despite being fit for out-patient treatment. Enhanced Recovery After Surgery (ERAS) protocols have been gradually adapted in local surgical units in recent years, but no data on their efficacy in gastrectomy patients have been reported.15 With wider implementation of ERAS and better patient education, it is expected that differences in LOS between types of surgery will become even more apparent.

About half (53%) of the operations performed in this study were total gastrectomies, and all patients had advanced gastric cancer; both of these factors have been associated with longer OT in the literature.16 The OT inherent to the laparoscopic approach has been reported as longer in many studies, but the median OT of LG was 44 minutes shorter than that of open surgery in our series. This may be partly explained by the more complex procedures expected in patients chosen for open gastrectomies. For example, en bloc splenectomy and distal pancreatectomy were only performed in the open group, despite the between-group differences in frequency not reaching statistical significance. Further, the overall histories of laparotomy, tumour location, and clinical and pathological staging were comparable between the two groups. Another explanation for the shorter OT observed in LG in our study is the maturation of our surgeons’ laparoscopic technique. The higher ratio of total gastrectomies (50%-54%) compared with literature values was caused by pathological characteristics and surgeon preference. The 42% of cases with distally located tumours accounted for a compatible 43% of cases in which distal gastrectomies were performed. In contrast, for the remaining tumours in the gastric cardia or body, because 70% of tumours were Bormann types 3 and 4, total gastrectomy was the curative operation of choice.

The median number of lymph nodes harvested was significantly higher in the LG group (37 compared with 26 in the open group). Both groups had more lymph nodes harvested than the 15 required for proper staging. Laparoscopic D2 lymphadenectomy is a technically challenging procedure, especially at Stations 4, 6, 9, and 11 and in spleen-preserving lymphadenectomy at the splenic hilum. However, advances in optics have offered unparalleled amplified clarity for identification of anatomical structures. The latest laparoscopic energy devices have also enabled pinpoint precision while performing dissection and sealing in extensive lymphadenectomies.17 With time and experience, there are indications that our centre’s surgeons have overcome the learning curve involved.

The importance of adjuvant chemotherapy in curing advanced gastric cancer cannot be undermined, as many cases have occult micrometastases. Yet, it has been reported that only 48% to 67% of patients indicated for adjuvant chemotherapy had it successfully administered, with postoperative morbidity being a significant factor behind this deficiency.3 The advantages of fewer minor complications, shorter LOS, and overall better general condition of patients may potentially benefit those who undergo LG and are eligible for adjuvant therapy. Such eligibility was shown in 41% of patients who underwent LG versus 28% in the open group, but the difference barely fell short of reaching statistical significance (P=0.093). Higher rates of receiving adjuvant treatment may translate into the significantly lower disease recurrence of 9% in the LG group compared with 28% in the open group (P=0.005). No differences in 5-year DFS nor OS were demonstrated between the groups. Further large-scale, multicentre randomised controlled trials like the Korean Laparo-endoscopic Gastrointestinal Surgery Study (KLASS-02; registered at www.clinicaltrials.gov as NCT01456598), the Japanese Laparoscopic Gastric Surgery Study Group (JLSSG 0901; registered at www.umin.ac.jp/ctr/ as UMIN000003420), and the Chinese Laparoscopic Gastrointestinal Surgery Study (CLASS-01; registered at www.clinicaltrials.gov as NCT01609309) are needed to elucidate the short- and long-term results of LG for advanced gastric cancer.

The limitations of our study include its retrospective and single-centre nature and its limited number of participants and follow-up period. Anticipated en bloc distal pancreatectomy and splenectomy were handled exclusively via the open approach in this series. With increasing experience, it may be possible to perform these adjunct procedures laparoscopically, yielding more homogenous groups for comparison. Efforts have been made to minimise recall and observer bias and to reduce selection bias through matching.

In summary, LG was associated with shorter OT, less blood loss, fewer minor complications, shorter LOS, higher lymph node yield, and, importantly, lower rates of disease recurrence. Overall complications, 30-day mortality, margin clearance, pathological stage, percentage receiving adjuvant therapy, and survival time were comparable between groups. Despite this study’s retrospective cohort nature, which limits its generalisability, because of the characteristics of our patient base and the level of our hospital, we believe that our results are representative of the latest Hong Kong experience.

Laparoscopic gastrectomy is effective and safe as a curative treatment for patients with advanced gastric adenocarcinoma in Hong Kong. Apart from its overall equivalent operative and oncological outcomes, it benefited patients by being associated with less morbidity, shorter LOS, and higher lymph node clearance than open surgery. This represents the first local study of its type and illustrates the maturity of LG as a first-line treatment in our surgical department.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

Concept and design of study: All authors.
Acquisition of data: BYO Chan, CKO Chan.
Analysis and interpretation of data: All authors.
Drafting of manuscript: BYO Chan.
Critical revision for important intellectual content: All authors.

The authors have no conflicts of interest to disclose.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

This study was approved by the Hospital Authority Kowloon Central Cluster/Kowloon East Cluster Research Ethics Committee (Ref No. KC/KE-18-0100/ER-1).

1. International Agency for Research on Cancer, World Health Organization. GLOBOCAN 2012 v1.1, cancer incidence and mortality worldwide: IARC CancerBase No. 11. 2014. Available from: http://globocan.iarc.fr. Accessed 1 Jun 2018.

2. Wang JF, Zhang SZ, Zhang NY, et al. Laparoscopic gastrectomy versus open gastrectomy for elderly patients with gastric cancer: a systematic review and meta-analysis. World J Surg Oncol 2016;14:90. Crossref

3. Kelly KJ, Selby L, Chou JF, et al. Laparoscopic versus open gastrectomy for gastric adenocarcinoma in the west: a case-control study. Ann Surg Oncol 2015;22:3590-6. Crossref

4. Kim HH, Han SU, Kim MC, et al. Long-term results of laparoscopic gastrectomy for gastric cancer: a large-scale case-control and case-matched Korean multicenter study. J Clin Oncol 2014;32:627-33. Crossref

5. Gholami S, Cassidy MR, Strong VE. Minimally invasive surgical approaches to gastric resection. Surg Clin North Am 2017;97:249-64. Crossref

6. Japanese Gastric Cancer Association. Japanese classification of gastric carcinoma: 3rd English edition. Gastric Cancer 2011;14:101-12. Crossref

7. Kitano S, Iso Y, Moriyama M, Sugimachi K. Laparoscopy-assisted Billroth I gastrectomy. Surg Laparosc Endosc 1994;4:146-8.

8. Viñeula EF, Gonen M, Brennan MF, Coit DG, Strong VE. Laparoscopic versus open distal gastrectomy for gastric cancer: a meta-analysis of randomized controlled trials and high-quality nonrandomized studies. Ann Surg 2012;255:446-56. Crossref

9. Son T, Hyung WJ. Laparoscopic gastric cancer surgery: current evidence and future perspectives. World J Gastroenterol 2016;22:727-35. Crossref

10. Wei HB, Wei B, Qi CL, et al. Laparoscopic versus open gastrectomy with D2 lymph node dissection for gastric cancer: a meta-analysis. Surg Laparosc Endosc Percutan Tech 2011;21:383-90. Crossref

11. Uyama I, Suda K, Satoh S. Laparoscopic surgery for advanced gastric cancer: current status and future perspectives. J Gastric Cancer 2013;13:19-25. Crossref

12. Shinohara T, Satoh S, Kanaya S, et al. Laparoscopic versus open D2 gastrectomy for advanced gastric cancer: a retrospective cohort study. Surg Endosc 2013;27:286-94. Crossref

13. Hospital Authority. Hong Kong Cancer Registry. Available from: www3.ha.org.hk/cancereg. Accessed 1 Jun 2018.

14. Tang J, Humes DJ, Gemmil E, Welch NT, Parsons SL, Catton JA. Reduction in length of stay for patients undergoing oesophageal and gastric resections with implementation of enhanced recovery packages. Ann R Coll Surg Engl 2013;95:323-8. Crossref

15. Mortensen K, Nilsson M, Slim K, et al. Consensus guidelines for enhanced recovery after gastrectomy: Enhanced Recovery After Surgery (ERAS®) Society recommendations. Br J Surg 2014;101:1209-29. Crossref

16. Nozoe T, Kouno M, Iguchi T, Maeda T, Ezaki T. Effect of prolongation of operative time on the outcome of patients with gastric carcinoma. Oncol Lett 2012;4:119-22. Crossref

17. Rosati R, Parise P, Giannone Codiglione F. Technical pro & cons of the laparoscopic lymphadenectomy. Transl Gastroenterol Hepatol 2016;1:93. Crossref

Lower urinary tract symptoms (LUTS) can affect patients of both sexes and of all ages.1 Although LUTS are regarded by the most cultures as an inevitable consequence of ageing, bother from LUTS varies among populations.2 Assessment of bother from symptoms is important, because the degree of bother affects quality of life (QoL) and medical help seeking behaviour.3 4

There are few studies investigating the correlation between LUTS and drinking habits, especially among Asian populations. Daily routines and dietary habits are largely dependent on cultural background; therefore, LUTS might vary in this perspective. In addition, up-to-date evidence on the impact of LUTS on mental health, as well as on the general well-being of an individual, is scarce. Most studies have investigated LUTS as a collective symptom entity.5 Few studies have investigated the relationship between individual symptoms and psychological stress.

The purpose of the present study is to provide an updated perspective on LUTS in an Asian population including both men and women. The present study aimed to clarify the prevalence of the subcategories of LUTS—voiding symptoms, storage symptoms, and nocturia—through a telephone survey. Furthermore, we investigated medical background and lifestyle factors that might have precipitated LUTS. Last, we assessed the effect of LUTS on the mental health and general well-being of individual patients. We also evaluated the level of bother caused by individual symptoms in relation to medical help seeking behaviour.

This was a random telephone survey of the general population in Hong Kong. Inclusion criteria were men or women aged ≥40 years of Chinese ethnicity. Subjects who were not able to comprehend the telephone survey were excluded from the study. Local census data report a ≥40-year-old population of 3 875 800 in 2013.6 Anticipating a confidence level of 95% and margin of error of 3%, 1000 respondents were targeted to complete the survey.

The survey consisted of seven parts. Basic demographics were collected, including age, sex, marital status, education level, occupation, and individual monthly income. Medical background and drinking habits were explored by questions on smoking history, beverage consumption habits, general medical and mental health history, urological history, and medical help seeking behaviour. Any LUTS were assessed with the International Prostate Symptom Score (IPSS) or the overactive bladder symptom score.7 The Patient Health Questionnaire-9 (PHQ-9) was used to assess depressive symptoms among the respondents. The PHQ-9 scores ≥10 have a sensitivity of 88% and a specificity of 88% for major depression. The PHQ-9 scores of 5, 10, 15, and 20 represent mild, moderate, moderately severe, and severe depression, respectively.8 The Short Form (SF)–12v2 Health Survey was used to assess health-related QoL. The International Index of Erectile Function was used to assess sexual function in male respondents who were sexually active in the preceding 4 weeks.9 Figure 1 shows the survey question flow. To avoid unnecessary embarrassment and to improve compliance, questions on sexual health were asked by a pre-recorded computer-generated voice programme. Subjects answered the questions by pressing the appropriate number key on the phone keypad.

The interviews were carried out from March to May 2017. To minimise the sampling error, telephone numbers were first selected randomly from an updated telephone directory as seed numbers. Another three sets of numbers were then generated using randomisation of the last two digitals to recruit unlisted numbers. Duplicate numbers were screened out, and the remaining numbers were mixed in a random order to become the final sample. Interviews were carried out by experienced interviewers, between 18:00 and 22:00 on weekdays or at other convenient times, including weekends and public holidays, arranged with suitable subjects. Upon successful contact with a target household, one qualified member of the household was selected among those family members using the last-birthday random selection method (ie, the respondent aged ≥40 years in a household who had most recently had a birthday would be selected to participate in the telephone interview). Principles of the Declaration of Helsinki were followed. The study was performed in compliance with Good Clinical Practice. All participants provided informed consent before participating in the study.

Descriptive statistics were used to characterise the clinical characteristics of the survey cohort. Spearman correlation was used to investigate the relationships between different age-groups and severity of LUTS. Chi squared test or Fisher’s exact test was applied for categorical data. Univariate and multivariable logistic regression analyses were performed to identify clinical covariates that were significantly associated with LUTS. The P value of <0.05 were considered statistically significant. The SPSS (Windows version 24.0; IBM Corp, Armonk [NY], US) was used for all calculations.

A total of 18 881 calls were made, among which 17 338 were invalid cases, including non-residential lines, invalid lines, non-eligible respondents, or having the line cut immediately before the survey could start. Another 543 eligible respondents were excluded because they refused to participate in the survey after being informed of the nature of the study. In the end we received 1000 valid responses, achieving a response rate of 64.8% after excluding the invalid numbers. Table 1 includes the demographics of the respondents and their drinking habits. Most respondents did not regularly drink coffee, but 30.5% of respondents reported drinking tea more than once per day.

In total, 774 respondents (77.4%) reported a certain degree of LUTS (Table 2). Among respondents with LUTS, 89.5% had mild symptoms, 8.9% had moderate symptoms, and 1.6% experience severe symptoms. Men had more LUTS than did women (mean ± standard deviation [SD]: men, 3.62 ± 4.86; women, 2.56 ± 3.34; P=0.002). The older the subject, the poorer the LUTS and QoL scores (mean IPSS: 40-59 years, 1.37 ± 2.05; 60-79 years, 3.32 ± 4.28; ≥80 years, 4.48 ± 4.45; P<0.001; mean QoL score: 40-59 years, 1.15 ± 0.91; 60-79 years, 1.85 ± 1.13; ≥80 years, 2.25 ± 1.13; P<0.001). In the storage symptom domain of IPSS, sex did not show any significant difference in mean total storage symptom score (men, 2.32 ± 2.48; women, 1.91 ± 1.97; P=0.052). The older the age, the more prevalent the storage and voiding symptoms (storage symptom score: r=0.434, P<0.001; voiding symptom score: r=0.190, P<0.001). Mean total storage symptom score across different age-groups were: 40-59 years, 1.01 ± 1.29; 60-79 years, 2.30 ± 2.27; ≥80 years, 3.23 ± 2.25; P<0.001. The age-adjusted prevalence of any urgency symptom in our survey was 15 096 per 100 000 population. If we only include symptoms of urgency more than once per week, the age-adjusted prevalence was 4070 per 100 000 population. Furthermore, more storage symptoms than voiding symptoms were experienced by respondents at any age-group (Fig 2).

If we exclude nocturia 1 time per night only as part of LUTS or part of storage symptoms, a total of 191 (63.2%) men were found to have LUTS in this survey. In this group of respondents, 71 (37.2%) reported only having storage symptoms, 19 (9.9%) reported only having voiding symptoms, and 101 (52.9%) reported having both storage and voiding symptoms. Similarly, 348 (49.9%) women were found to have LUTS: 181 (52.0%) reported only having storage symptoms, 19 (5.5%) reported only having voiding symptoms, and 148 (42.5%) reported having both storage and voiding symptoms.

Figure 3 shows the prevalence of nocturia among the respondents with LUTS. Among those with LUTS, 128 (67.0%) men and 230 (66.1%) women reported having nocturia twice or more per night. The median number of nocturia episodes increased with age (men, r=0.510; P<0.001; women, r=0.418; P<0.001).

Table 1 includes the general health status and mental health status of the respondents by means of SF-12v2 score and PHQ score, respectively. As shown in Table 3, both PHQ-9 scores and SF-12v2 scores were found to be correlated with both storage symptoms and voiding symptoms. The higher the PHQ-9 score—indicating more prominent depressive symptoms—the more significant the LUTS. Similarly, in the SF-12v2 assessment of general health, the higher the score—indicating poorer health—the more significant LUTS. Storage symptoms and voiding symptoms were found to be negatively correlated with all components of the SF-12v2.

The results of storage and voiding symptoms regression analysis are shown in Table 3. Age, presence of hypertension, and diabetes were found to be significantly correlated with storage symptoms. In contrast, male sex, presence of hypertension, diabetes, ischaemic heart disease, and stroke were found to be significantly positively correlated with voiding symptoms.

Concerning medical help seeking behaviour among men, 37.5% of men with severe LUTS, 16.7% with moderate LUTS, and 7.9% with mild LUTS sought medical help. No women with moderate LUTS sought medical help. For women with mild LUTS, 2.5% sought medical help. Among the patients with LUTS who sought medical help, the most prominent symptoms were nocturia (mean IPSS, 1.80±1.32) and urgency (mean IPSS, 0.97±1.67).

In general, LUTS include storage symptoms and voiding symptoms. Storage symptoms include urinary frequency, nocturia, urinary urgency, and urinary incontinence. Voiding symptoms include slow stream, intermittent stream, hesitancy, and straining.10

According to our survey, 77.8% of men and 77.3% of women aged ≥40 years reported at least mild degree of LUTS according to IPSS assessment. This prevalence was relatively lower than an internet survey carried out in mainland China, Taiwan and South Korea, which reported 86.8% of participants having at least mild symptoms on IPSS.1 However, our findings were comparable to the EpiLUTS study performed in the US, the United Kingdom and Sweden, which demonstrated the prevalence of at least one LUTS was 72.3% for men and 76.3% for women.11 In a study of LUTS in Canada, Germany, Italy, Sweden, and the United Kingdom, Irwin et al12 reported an even lower prevalence of LUTS, with an overall prevalence of any LUTS of 62.5% in men and 66.6% in women. Although such differences in LUTS prevalence across studies could be attributed to different populations, different cultural backgrounds or methodological variations could also account for this observation. Linguistic interpretation discrepancy and different levels of severity or frequency being used to determine the presence of symptoms would also generate different results. In addition, changes in general health awareness and in the socio-economic environment might also effect survey outcomes. Furthermore, some studies have suggested seasonal variations of LUTS, with symptoms being more prominent in winter.13 14 Our survey was carried out in spring and early summer, which could possibly account for our results falling into the median range in the literature.

Overactive bladder is a subset of storage LUTS, currently defined by the International Continence Society as urgency, with or without urgency incontinence, usually with frequency and nocturia.10 Our survey included overactive bladder symptom score as one of the tools to assess the prevalence of storage symptoms in our population. In the present study, the prevalence of any experience of urgency was 19.5% for men and 19.1% for women. This is in line with survey results from Europe, where Milsom et al15 reported the prevalence of overactive bladder symptoms to be 16.6%, and from the US, where Stewart et al16 reported the prevalence of overactive bladder symptoms to be 16.0% in men and 16.9% in women. However, for clinically significant overactive bladder symptoms, urgency must be happening more than once per week. With this refinement, our study found that 8.6% of men and 5.3% of women reported urgency more than once per week. This group of patients warrants urological attention and intervention.

Voiding symptoms that are often associated with bladder outlet obstruction in men were also found to be common among women. In accordance with other studies in the literature,1 11 12 our survey confirmed that the prevalence of LUTS increases with age. In particular, storage symptoms were reported more often than voiding symptoms (Fig 2). Furthermore, age, hypertension, and diabetes were found to correlate with storage symptoms on multiple logistic regression (Table 3). Such observations conform to the findings by Ng et al,17 who noticed that in their cohort of 617 men with LUTS, 43% had hypertension and 29% had dysglycaemia. In addition, Ng et al17 also reported that patients with moderate-to-severe LUTS had a significantly higher chance of having at least one cardiovascular risk factor during assessment. These results are echoed in an updated and more detailed analysis of 966 men with LUTS.18 Yee et al18 demonstrated that the severity of LUTS was significantly positively correlated with Framingham score, which is an estimate of the risk of coronary heart disease taking into account of age, sex, smoking status, cholesterol levels, blood pressure, and hypertensive treatments. This supports the hypothesis that atherosclerosis leads to pelvis and bladder ischaemia, and that this might be one of the mechanisms leading to LUTS.19

Studies on the effect of caffeinated drinks on LUTS are scarce, and most have been on urinary incontinence. Davis et al20 reported that caffeine consumption was significantly associated with moderate-to-severe urinary incontinence in men from the US National Health and Nutrition Examination Survey. A similar finding was reported by Baek et al21 from the Korean National Health and Nutritional Examination Survey among postmenopausal women. However, our study did not find such a correlation. On the contrary, the consumption of caffeinated drink correlates negatively with storage symptoms in general (Table 3). One possible explanation for this contradiction is that respondents with significant storage symptoms had usually already cut down their caffeine intake. Thus, our survey could not illustrate the true impact of caffeinated drinks on overactive bladder symptoms. In addition to beverage consumption habits, a lower education level was another factor we found correlating with storage and voiding symptoms (Table 3). Another study proposed that knowledge on health and disease perception, which might be a function of education level, would lower the perceived severity of LUTS.22

In a prospective cohort of elderly men, Chung et al23 showed that the presence of moderate-to-severe LUTS at baseline was significantly associated with increased risk for being depressed at 2-year follow-up. The current study found that, individually, storage symptoms and voiding symptoms were correlated with a higher PHQ score, translating into a higher risk of depression. Furthermore, both storage and voiding symptoms were negatively correlated with all components of general health as measured by SF-12v2. These findings highlight the importance of LUTS management, considering its prevalence and its effect on individual well-being.

A significant percentage of respondents with LUTS did not seek medical help. A similar result has been observed in other Southeast Asian countries.1 Possible reasons for a low rate of medical help seeking behaviour include social stigma or a common belief that LUTS is unavoidable with ageing. A multinational cross-sectional survey on men seeking medical help for LUTS found that nocturia was the most common symptom among these patients (88%).24 Our study demonstrated that, not only was nocturia a common symptom which drove respondents to seek medical help, it was also the most bothering symptom with the highest symptom score (Table 4). This suggests that nocturia is one of the most important symptoms that drive patients to seek medical help. However, management of nocturia is still a challenge for urologists. Cutting fluid intake alone was not found to be useful in prolonging the duration between the time retiring to bed and the first nocturia episode.25 Antidiuretics are presently the only treatment that provide consistent response in the setting of nocturnal polyuria.26

Limitations of the present study include the bias from self-reports to measure LUTS, which might be prone to inaccuracy when compared with physician assessment. However, a meticulous physical examination would not be possible in the setting of a large-scale epidemiological study. The telephone interview cam eliminate the limitation of illiteracy that might be present in self-administered questionnaires; however, such interviews might introduce bias from each interviewer’s technique, as well as time pressure on respondents. The interviewers in our study were professional interviewers with vast experience in medical research. This minimised potential interview bias.

This population-based survey confirms that LUTS is common among both men and women. Symptoms increase with age, significantly affecting patient mental and general health. Storage symptoms are more prominent than voiding symptoms, with nocturia being the most bothering symptom. A significant percentage of respondents with LUTS did not seek medical help. Future research and investigation should address this deficit.

All authors have made substantial contributions to the concept or design of this study; acquisition of data; analysis or interpretation of data; drafting of the manuscript; and critical revision for important intellectual content. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

The authors have no conflicts of interest to disclose.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Ethics approval was obtained from the Joint Chinese University of Hong Kong-New Territories East Cluster Clinical Research Ethics Committee (Ref. CRE-2016.588).

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25. Teoh JY, Chan C, Ng CA, et al. Desmopressin oral lyophilisate lessens the burden of nocturia in the post-TURP men sooner they go asleep—an action unreachable by fluid restriction alone but attenuated by aging. International Continence Society 2017 Florence. Available from: https://www.ics.org/2017/abstract/626. Accessed 11 Mar 2018.

26. Sakalis VI, Karavitakis M, Bedretdinova D, et al. Medical treatment of nocturia in men with lower urinary tract symptoms: systematic review by the European Association of Urology Guidelines Panel for male lower urinary tract symptoms. Eur Urol 2017;72:757-69. Crossref

Patients frequently present to emergency departments (EDs) with headache. About 4.5% of total ED attendance in the United States is attributable to headache,1 1% to 6% of which is caused by non-traumatic subarachnoid haemorrhage (SAH).2 3 4 Among the volume of neurologically intact patients with severe acute headache, identifying the 10% with ‘walking SAH’—patients with SAH but maximum Glasgow Coma Scale score and normal neurological examination—is particularly difficult.5 Specifically, those patients have good Hunt and Hess grading and generally better prognosis.6 Failure to identify those SAH patients would jeopardise those patients’ otherwise good outcomes. A case series demonstrated that 25% of aneurysmal patients with SAH were misdiagnosed during their initial medical evaluations, 38% of which had clinical grade 1 or 2 at the time of misdiagnosis.7 Overall, 24% of patients deteriorated before the correct diagnosis was made, with poor or worse final outcomes. Most of the misdiagnoses of SAH cases were caused by failure to perform computed tomography (CT) imaging. Another study reported that 12% of patients with SAH were initially misdiagnosed, of which 19% had normal mental status at first contact, and these misdiagnoses were associated with worse quality of life at 3 months and increased risk of death or severe disability at 12 months.4 Again, failure to conduct CT scanning was the most common cause, accounting for 73% of diagnostic errors. However, conducting a CT scan on every single patient who attends an ED for headache may not be practical, in consideration of radiation exposure to patients and resource implications. For such purposes, clinical prediction rules including the Ottawa SAH rule have been developed for identification of low-risk patients who can be discharged safely without a CT scan or other imaging (Table 1).4 However, those clinical prediction rules have not been well validated in the Asian Chinese population. The primary objective of the current study is to validate the Ottawa SAH rule in the Asian Chinese population. The secondary objective is to identify possible modifications to improve its accuracy.

This was a retrospective cohort study conducted in the EDs of two regional hospitals in Hong Kong. With daily attendance of approximately 600 and 350 patients, respectively, Tuen Mun Hospital and Pok Oi Hospital together serve a population of over 1 million. All patients are coded according to principal diagnosis following the International Classification of Diseases, Ninth Edition (ICD-9).8 Case recruitment had two phases. First, we searched the hospital’s electronic database for ICD-9 codes indicating headache symptoms, related syndromes, and diseases that may present with a primary complaint of headache (online Supplementary Appendix). In the second phase of case inclusion, the medical records of all cases retrieved in the first phase were screened for eligibility to be included in the current study according to the inclusion and exclusion criteria.

All patients aged ≥16 years who presented with acute headache to the study centres from July 2013 to June 2016 were included. Acute headache was defined as non-traumatic headache that reached maximal intensity within 1 hour, with an interval of <14 days from headache onset to presentation. The clinical details of each retrieved case were screened for inclusion eligibility by both written and electronic medical records. Cases with obvious pathology (eg, frontal sinusitis) were excluded. Exclusion criteria included age <16 years, history of trauma within the last 7 days (collapse associated with headache onset leading to head injury was not an exclusion), history of previous SAH, known cerebral aneurysm or cerebral neoplasm, >14 days since symptom onset, altered mental state, Glasgow Coma Scale score <15 on presentation, and new focal neurological signs. Patients were still included if they had recurrent ED attendance during the study period.

A detailed manual review of written and electronic medical and radiological records was conducted to obtain the following data for eligible cases: duration and quality of headache, presence of thunderclap headache, neck pain, limited range of neck movement, loss of consciousness (LOC), onset with exertion, arrival by ambulance, failure of ambulation in previously ambulatory patients, associated symptoms of dizziness and vomiting, history of benign headache syndrome, concomitant anticoagulant usage or known bleeding diathesis, presenting Glasgow Coma Scale score, blood pressure and heart rate (the first recorded values in the ED), neurological deficits, imaging, lumbar puncture, definitive diagnosis, and neurological outcome. Criteria not documented in the medical records were presumed to be absent. Standardised data collection forms were deployed for data entry by a single investigator.

Subarachnoid haemorrhage was defined in accordance with Perry et al9: subarachnoid blood on CT scan, xanthochromia in cerebrospinal fluid, or red blood cells in the final tube of cerebrospinal fluid, with positive angiography findings (ie, an aneurysm or arteriovenous malformation on cerebral angiography). All CT films were reviewed by both an experienced emergency physician and a radiology fellow, with outcome decided by consensus.

The study outcomes included the sensitivity of the Ottawa SAH rule (Table 1) and the impact on the accuracy of the Ottawa SAH rule of addition of the following clinical predictors to the proposed clinical decision rule: systolic blood pressure (SBP) >160 mm Hg, diastolic blood pressure >100 mm Hg, vomiting, failure of ambulation in previously ambulatory patients, bleeding diathesis or on anticoagulants, and existence of a benign headache disorder that could account for the headache.

R 3.4.1 for Windows (R Foundation for Statistical Computing, Vienna, Austria) was employed for analysis, and a 5% significance level was adopted. Continuous data were presented as mean and standard deviation if normally distributed. Categorical variables were shown as frequencies and percentages. For univariate analysis, comparison was performed between patients in the non-SAH and SAH groups using independent samples t tests, Chi squared tests, and Fisher’s exact test where appropriate. Predictors that were significant in the univariate analysis were entered into the logistic regression model by a forward stepwise method based on likelihood ratios. Adjusted odds ratios (AORs) and P values were calculated for each predictor. The Hosmer-Lemeshow goodness-of-fit test was adopted for model calibration. Model discrimination was evaluated by the area under the receiver operating characteristic (ROC) curve of the predicted probabilities. Collinearity was explored with variance inflation factors. Net reclassification improvement and integrated discrimination improvement indices were calculated to assess the improvement of model prediction with the addition of significant variables to the Ottawa SAH rule.

The Ottawa SAH rule (Table 1) was applied to calculate the sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, and their corresponding 95% confidence intervals (95% CIs). The modified Ottawa SAH rule was created on the basis of the additional independent predictors included in the logistic model and the diagnostic characteristics evaluated.

Sample size was calculated to yield 80% power at a 5% significance level. These calculations assumed SAH prevalence of 6.5%, and the original derivation paper of the Ottawa SAH rule achieved 100% sensitivity and 15.3% specificity.4 With two-tailed hypothesis testing, to achieve the same specificity and 10% variation of sensitivity, a sample of 500 subjects with 31 cases of SAH would be required. Sample size calculation was performed with NCSS PASS 11 (Version 11.0.10).

A total of 1816 potential headache cases during the study period were retrieved from the hospitals’ databases. After a detailed review of clinical information, 500 eligible cases were included in the analysis, in 50 of which SAH was confirmed (10%) [Fig 1]. There were missing values for major components of the Ottawa SAH rule in 16% of the included cases. Two out of the 50 SAH cases had negative CT results (Fisher scale 1), and both of these cases were detected by xanthochromia in cerebrospinal fluid extracted by lumbar puncture. In terms of angiographic findings, angiography was not performed in five patients; six patients had normal angiograms; two had arteriovenous fistulae; one had moyamoya disease; two had cerebral amyloid vasculopathy; and the SAHs of the remaining 34 (68%) patients were aneurysm-related.

The demographic and clinical characteristics of the included cohort are shown in Table 2. The SAH group was contrasted with the non-SAH group in terms of various clinical characteristics. Lumbar puncture was performed in 50 patients, and two patients had xanthochromia in the extracted cerebrospinal fluid. Another 48 patients had SAH diagnosed by CT. Logistic regression (Table 3) revealed that LOC (AOR=16.3; P<0.001) and thunderclap headache (AOR=12.4; P<0.001) were the strongest predictive parameters for SAH. In addition to the parameters in the Ottawa SAH rule, vomiting and SBP >160 mm Hg were demonstrated to be independent predictors of SAH. The Hosmer-Lemeshow goodness-of-fit test demonstrated satisfactory model calibration (P=0.986). Area under the ROC curve for the Ottawa SAH rule was 0.819 (95% CI=0.782-0.851) [Fig 2]. The variance inflation factors of predictors ranged from 1.03 to 1.15, indicating non-significant multicollinearity. The modified Ottawa SAH rule was defined as positive prediction of SAH with the occurrence of any of the following criteria: vomiting, SBP >160 mm Hg, or any of the parameters of the Ottawa SAH rule (Table 1). The area under the ROC curve of the modified Ottawa SAH rule in combination with vomiting and SBP >160 mm Hg increased to 0.870 (95% CI=0.837-0.898). Non-parametric comparison of the areas under the ROC curves demonstrated a statistically significant difference (P=0.041). The net reclassification improvement index was 0.158 (95% CI=0.007-0.309; P=0.040), and the integrated discrimination improvement index was 0.622 (95% CI=0.353-0.891; P<0.001). Both indices indicate that the addition of vomiting and SBP >160 mm Hg would improve the model’s discriminatory and predictive capacity.

Table 4 describes the diagnostic characteristics of various clinical prediction rules that predict SAH in patients with acute headache. The Ottawa SAH rule achieved 94% (95% CI=82.5-98.4%) sensitivity and 32.9% (95% CI=28.6-37.5%) specificity. The modified Ottawa SAH rule in combination with both vomiting and SBP >160 mm Hg produced sensitivity of 100% (95% CI=91.1-100%) and specificity of 13.1% (95% CI=10.2-16.7%).

For 349 out of the 500 included patients, positive predictions would have been rendered by the Ottawa SAH rule, as one or more of its criteria were satisfied (69.8%). For 441 out of the 500 patients, positive predictions would have been rendered by satisfying one or more criteria of the modified Ottawa SAH rule (88.2%). The clinical implication is that 69.8% and 88.2% of the included patients would have required CT according to the Ottawa and modified Ottawa SAH rules, respectively (Table 4). In our cohort, CT was performed in the ED on a total of 481 (96.2%) patients. Thus, application of the Ottawa and modified Ottawa SAH rules can reduce CT administration by 26% and 8%, respectively.

Three patients with SAH were not identified by the Ottawa SAH rule. All three of them were relatively young (aged 20-38 years). Two of them were initially discharged home, with initial negative imaging for SAH, and were diagnosed upon re-attending the accident and emergency departments. Of those two, one patient later developed signs of meningeal irritation with xanthochromia revealed by lumbar puncture, and the other patient was called back to the hospital 7 days later after a retrospective CT report found hydrocephalus and collapsed in the medical ward. A repeat CT scan showed diffuse SAH. Those patients’ mild symptoms at first presentation that led to their initial discharges might account for their falsely negative Ottawa SAH rule findings. In addition, patients who wanted to go home might have been more tolerant of pain and more reluctant to describe alarming symptoms. The former patient was initially diagnosed with reversible cerebral vasoconstriction syndrome, and SAH was noted when the patient subsequently re-attended the ED. This might explain his atypical presentation in comparison with other patients with SAH who had ruptured intracranial aneurysms and tended to present with more florid symptoms from the beginning. The latter patient was diagnosed with a ruptured anterior communicating artery aneurysm. The third patient had a positive CT scan, and digital subtraction angiography showed a ruptured distal internal carotid aneurysm. All three patients experienced vomiting, and two of them had SBP >160 mm Hg.

Various investigations have attempted to identify clinical parameters to predict SAH among patients presenting with non-traumatic headache. The identified predictors include: age >40 years, neck pain or stiffness, LOC, onset with exertion, arrival by ambulance, vomiting at least once, diastolic blood pressure >100 mm Hg, and SBP >160 mm Hg.3 10 11 In the last decade, clinical prediction rules have combined various predictors to provide better accuracy in diagnosis of SAH.4 12 13 The Ottawa SAH rule is one of the best known ones, and it has been subject to external validation.4 An external validation study of the Ottawa SAH rule reported sensitivity of 100% and specificity of 7.6%.14

The SAH incidence rate in our study was noticeably higher than that in the original derivation study and other validation studies.11 14 15 This is not consistent with previous epidemiological studies that reported Chinese people to have a lower rate of aneurysmal SAH than that of other populations.16 One possible explanation is that our inclusion criteria were more stringent, as headache cases with obvious accountable causes were excluded. The mean age and SBP of our cohort were similar to those of other studies.12 13 14 15 Only 8.8% of our included patients reported thunderclap headache, much lower than the 78% to 89% reported in previous studies.4 14 However, the causes of headache in patients with non-SAH headache are mostly benign, and the pattern of benign headache syndromes may be different in the Chinese population compared with that in Caucasians (ie, migraine is more prevalent in Caucasians).17 The rate of onset during exertion was much lower in our cohort than in those of previous studies, as were neck pain and reduced range of movement.14 15 The exact reason for the latter is unknown. One possible explanation is that there are more cervicogenic headaches and occipital neuralgia in the other study cohorts. Conversely, we reported higher rates of arrival by ambulance, vomiting, and LOC,14 15 although one study excluded unwitnessed LOC.14 Loss of consciousness, thunderclap headache, vomiting, SBP >160 mm Hg, neck pain or limited neck range of movement, and age >40 years were found to be significant independent predictors of SAH. Onset during exertion had a high AOR, but its statistical significance was limited by its low incidence and limited sample size.

Both the original derivation study and the validation study by Bellolio et al14 reported that the Ottawa SAH rule had 100% sensitivity.15 In contrast, our study found that the Ottawa SAH rule was only 94% sensitive. The sensitivity of our study was limited by the low rates of onset during exertion, thunderclap headache, and neck pain or limited neck range of movement in our included patients. This might be partly attributable to our retrospective design, as unreported criteria were assumed to be absent. Moreover, the term thunderclap headache might be interpreted differently by different patients. Specificity was higher in our study than in others (32.9% in our study compared with 8%-15% in other studies).14 15 This may be attributed to the difference in the clinical characteristics of patients with non-traumatic headache in the Asian Chinese population compared with those in the original derivation study and other validation studies, which were mostly Caucasians.

Adding two independent predictors for SAH (vomiting and SBP >160 mm Hg) to the Ottawa SAH rule to produce a Modified Ottawa SAH rule improved its accuracy in terms of sensitivity. We found that three patients with SAH could not be identified by the Ottawa SAH rule. All three were relatively young, and two of them presented initially with mild symptoms and were discharged after brain CT did not show SAH. One patient was diagnosed with reversible cerebral vasoconstriction syndrome, which might present differently from the more common aneurysmal SAH. In a validation study,12 20% of patients with SAH were CT-negative, and most of them had posterior communicating artery aneurysm or normal digital subtraction angiography. However, our three patients did not share those clinical characteristics. Integration of vomiting and SBP >160 mm Hg to the model detected those cases and further improved sensitivity to 100% in our cohort.

The specificity of the Ottawa SAH rule was demonstrated to be low (15%) in the original derivation study.4 This implies that among patients without SAH, only 15% had negative predictions by the Ottawa rule, while the remaining 85% had positive predictions. The high false-positive prediction rate may have implications in terms of excessive unnecessary CT scans ordered: it may result in unnecessary radiation exposure, and the surge of CT requests might strain ED resources. With higher specificity in our cohort, we found that application of the Ottawa and modified Ottawa SAH rules can reduce CT use by 26% and 8%, respectively. A UK study found that if the Ottawa SAH rule had been applied, the CT investigation rate would have been much higher (59% to 74%) than the actual rate of 37%.18 Another UK study reported a similar CT investigation rate of 61.7% with the application of the Ottawa SAH rule, which was significantly higher than the rate of 54.2% in actual practice.19 A review surmised that while the Ottawa SAH rule seemingly can rule out SAH, in actual practice, it might increase the frequency of CT investigations.11 However, there is still a lack of impact analysis regarding the effects of the Ottawa SAH rule on patients’ neurological outcomes and mortality.

A clinical decision rule was recently proposed by Kimura et al20 in 2016. In their 1561-patient multicentre observational study, the authors aimed to identify concrete, unambiguous predictors for SAH, avoiding subjective terms like ‘thunderclap headache’. The EMERALD (Emergency Medicine, Registry Analysis, Learning and Diagnosis) SAH rule criteria are SBP >150 mm Hg, diastolic blood pressure >90 mm Hg, blood sugar >115 mg/dL (6.9 mmol/L), or serum potassium <3.9 mEq/L (3.9 mmol/L). Hyperglycaemia has been well reported in patients with SAH. Most studies have focused on the prognostic value of blood glucose, but there have been no other reports on the use of glucose levels for assistance with SAH diagnosis in the literature. Similarly, hypokalaemia has been reported in patients with SAH, which was postulated to be related to increased catecholamine secretion after SAH, resulting in higher intracellular potassium uptake and reduced serum potassium levels. While it requires blood sampling, the EMERALD SAH rule has been reported to have 100% sensitivity and 14.5% specificity, the latter of which is higher than that of the Ottawa SAH rule (8.8% in the study). Thus, more unnecessary CT scans could be avoided with the implementation of simple bedside point of care testing. However, the biological plausibility and external validity of this study might be affected by the lack of evidence about the mechanism of hyperglycaemia and hypokalaemia in patients with SAH, and further, patients with known diabetes mellitus were not excluded from this study. Patients with known cerebral aneurysm or new focal neurological deficits were also not excluded. Because CT scans would almost certainly be ordered for those patients, it might restrict this rule’s usefulness for detection of ‘walking SAH’. We cannot evaluate this rule, as our cohort was unlikely to undergo glucose and potassium sampling in the ED, and so far, we have not found any external validation studies for this clinical decision rule. Nevertheless, it is worth exploring whether the addition of blood glucose and potassium levels to the Ottawa SAH rule could improve its specificity and reduce unnecessary CT administration.

This study has several limitations. First, its retrospective design is prone to information bias. In total, 16% of the predictors were missing values in this study. With missing values, the prevalence of the predictors may be reduced, with potential effects on their diagnostic accuracy. Second, tracing of the outcome of whether or not the patients had SAH was limited because of the study’s retrospective nature. Further, if patients with SAH did not re-attend public hospitals but received treatment in private hospitals, the outcomes may have been missed. Third, as one study centre contains a neurosurgical department, there is a risk of referral bias. Cases diagnosed in other hospitals and referred to the study centre were excluded. In addition, as both study centres are located in the same cluster, SAH cases diagnosed at one study centre are often transferred to the other study centre for neurosurgical consultation at the ED there. Great care was taken to crosscheck between patients at the two study centres to avoid duplicate entry.

Although we exhaustively searched for all eligible cases, there was still a chance of selection bias, as some cases that were eligible according to the inclusion criteria may have been missed. While the Ottawa SAH rule is very sensitive, it is only applicable to a very specific group of patients with headache. Patients with headache that took marginally >1 hour to peak would be excluded. This greatly limits the rule’s clinical applicability throughout the population: one validation study reported that only 9% of patients with headache in an ED were applicable.14 The modified Ottawa SAH rule lacks an external cohort for validation in this study, and validation with an independent multicentre prospective cohort would be required to establish external validity.

In conclusion, the Ottawa SAH rule demonstrated high sensitivity. Addition of vomiting and SBP >160 mm Hg to the Ottawa SAH rule as criteria may increase its sensitivity.

All authors made substantial contributions to the concept or design of the study, acquisition of data, analysis or interpretation of data, drafting of the article, and critical revision for important intellectual content.

All authors have disclosed no conflicts of interest. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Approvals from the Hospital Authority New Territories West Cluster Ethics Committee were obtained.

1. Perry JJ, Stiell IG, Wells GA, et al. Attitudes and judgment of emergency physicians in the management of patients with acute headache. Acad Emerg Med 2005;12:33-7.

2. Vermeulen M, van Gijn J. The diagnosis of subarachnoid haemorrhage. J Neurol Neurosurg Psychiatry 1990;53:365-72. Crossref

3. Perry JJ, Stiell IG, Sivilotti ML, et al. High risk clinical characteristics for subarachnoid haemorrhage in patients with acute headache: prospective cohort study. BMJ 2010;341:c5204. Crossref

4. Perry JJ, Stiell IG, Sivilotti ML, et al. Clinical decision rules to rule out subarachnoid hemorrhage for acute headache. JAMA 2013;310:1248-55. Crossref

5. Edlow JA, Malek AM, Ogilvy CS. Aneurysmal subarachnoid hemorrhage: update for emergency physicians. J Emerg Med 2008;34:237-51. Crossref

6. Hunt WE, Hess RM. Surgical risk as related to time of intervention in the repair of intracranial aneurysms. J Neurosurg 1968;28:14-20. Crossref

7. Mayer PL, Awad IA, Todor R, et al. Misdiagnosis of symptomatic cerebral aneurysm. Prevalence and correlation with outcome at four institutions. Stroke 1996;27:1558-63. Crossref

8. International Classification of Diseases. Ninth Edition. Geneva, Switzerland: World Health Organization; 1977.

9. Perry JJ, Sivilotti ML, Sutherland J, et al. Validation of the Ottawa Subarachnoid Hemorrhage Rule in patients with acute headache. CMAJ 2017;189:E1379-85. Crossref

10. Lui CT, Tsui KL, Kam CW. Nuchal pain predicts subarachnoid haemorrhage in severe headache patients. Hong Kong J Emerg Med 2008;15:212-7. Crossref

11. Carpenter CR, Hussain AM, Ward MJ, et al. Spontaneous subarachnoid hemorrhage: a systematic review and meta-analysis describing the diagnostic accuracy of history, physical examination, imaging, and lumbar puncture with an exploration of test thresholds. Acad Emerg Med 2016;23:963-1003.Crossref

12. Mark DG, Hung YY, Offerman SR, et al. Nontraumatic subarachnoid hemorrhage in the setting of negative cranial computed tomography results: external validation of a clinical and imaging prediction rule. Ann Emerg Med 2013;62:1-10. Crossref

13. Kelly AM, Klim S, Edward S, Millar N. Sensitivity of proposed clinical decision rules for subarachnoid haemorrhage: an external validation study. Emerg Med Australas 2014;26:556-60. Crossref

14. Bellolio MF, Hess EP, Gilani WI, et al. External validation of the Ottawa subarachnoid hemorrhage clinical decision rule in patients with acute headache. Am J Emerg Med 2015;33:244-9. Crossref

15. Kowalski RG, Claassen J, Kreiter KT, et al. Initial misdiagnosis and outcome after subarachnoid hemorrhage. JAMA 2004;291:866-9.Crossref

16. de Rooij NK, Linn FH, van der Plas JA, Algra A, Rinkel GJ. Incidence of subarachnoid haemorrhage: a systematic review with emphasis on region, age, gender and time trends. J Neurol Neurosurg Psychiatry 2007;78:1365-72. Crossref

17. Stewart WF, Lipton RB, Liberman J. Variation in migraine prevalence by race. Neurology 1996;47:52-9. Crossref

18. Matloob SA, Roach J, Marcus HJ, O’Neill K, Nair R. Evaluation of the impact of the Canadian subarachnoid hemorrhage clinical decision rules on British practice. Br J Neurosurg 2013;27:603-6. Crossref

19. Yiangou A, Nikolenko N, Noreikaite J, Thondam S. Impact of subarachnoid haemorrhage Canadian clinical decision rule for investigation of acute headache, a retrospective case note review. Lancet 2017;389:S103. Crossref

20. Kimura A, Kobayashi K, Yamaguchi H, et al. New clinical decision rule to exclude subarachnoid hemorrhage for acute headache: a prospective multicenter observational study. BMJ Open 2016;6:e010999. Crossref

The global incidence rates of hospital-treated sepsis and severe sepsis have been estimated as 437 and 270 cases per 100 000 person years, respectively,1 accounting for 17% and 26% of hospital mortality, respectively. The same study estimated that 31.5 million cases of sepsis and 19.4 million cases of severe sepsis account for 5.3 million deaths annually worldwide.1 The ageing of the population and the increasing number of people living with co-morbid conditions are believed to be important factors associated with the increasing incidence of sepsis.2

In early 2016, sepsis was re-defined as ‘life-threatening organ dysfunction caused by a dysregulated host response to infection’ (Sepsis-3).3 The criteria used for identifying patients with sepsis were also updated, with the removal of the original systemic inflammatory response syndrome criteria that had been used since the early 1990s. The Sequential Organ Failure Assessment (SOFA) score is commonly used in intensive care units (ICUs) for assessment of organ dysfunction. The quickSOFA (qSOFA) score has been proposed as a bedside screening tool for patients at risk of sepsis with adverse outcomes in emergency departments (EDs) and other non-ICU settings. The evidence base for such a proposal is accumulating,4 and the optimal screening tool for sepsis in EDs has not yet been identified.5 6 7 8

The recent ProCESS,9 ProMISE,10 and ARISE trials11 confirmed the importance of early recognition with fluid resuscitation and appropriate antibiotic therapy in improving sepsis outcomes. These trials refuted the need for strict adherence to the haemodynamic goals proposed by Rivers et al in 2001 as early goal-directed therapy.12 Although it is generally agreed that early initiation of therapy is key to surviving sepsis, controversies remain regarding the initial rate and choice of fluids, the role and choice of inotropes, the identification of infection sources with imaging and other techniques, the use of appropriate antibiotics, and the optimal microbiological workup.13 14 15 16 17

The ED occupies a critical position in a patient’s journey of sepsis care and plays an important role in the early identification and treatment of sepsis.17 Despite frequent encounters with sepsis in EDs, few studies in Hong Kong have investigated sepsis care. Yang et al18 studied patients with sepsis and septic shock in a tertiary university teaching hospital and found no significant change in the in-hospital mortality rate after the implementation of sepsis guidelines (pre-implementation: 29.6% in 2009; post-implementation: 35.3% in 2010). Although a significant proportion (25.5% in 2009 and 40.2% in 2010) of the recruited patients had hypoperfusion (mean arterial pressure <65 mm Hg or lactate >4 mmol/L), only 10.4% to 11.8% had blood cultures drawn, 13.0% to 23.5% had antibiotics administered, and 24.5% to 29.6% had fluid resuscitation initiated in the ED. In that study, sepsis was recognised in the ED in only two-thirds of the patients with sepsis who presented there. Tse et al19 reported similar findings in their study on the impact of departmental sepsis guidelines on mortality (pre-implementation mortality: 25.8%; post-implementation mortality: 33%), although there were improved rates of blood culture collection and antibiotic administration in the ED after its implementation. Overall, 17.2% of patients required direct ICU admission.

Those studies highlighted a few important issues regarding sepsis care in Hong Kong EDs: a heavy burden of sepsis, low compliance with treatment guidelines, and poor patient outcomes despite efforts to standardise care. Evidently, implementing sepsis guidelines is insufficient, and there is a need to evaluate the whole process of care systematically. Moreover, those previous studies involved only individual EDs and, thus, might not be representative of other EDs. Furthermore, the adoption of international recommendations about sepsis care and the impact of the new Sepsis-3 definitions on ED practice are not known. We therefore conducted a survey to evaluate the process of sepsis care, the uptake of international recommendations and the Sepsis-3 definitions to departmental sepsis guidelines, and the barriers faced by health care providers in public EDs in Hong Kong.

This was a cross-sectional survey across all EDs in Hong Kong in 2017. All 18 public EDs under the Hospital Authority were invited to participate. Private EDs and 24-hour out-patient departments were excluded because 90% of in-patient care is provided by public hospitals in Hong Kong. One representative was nominated by the Chief of Service (medical director) of each ED to speak on behalf of the department, but not individuals. The telephone survey was based on an interview guide provided before the interview (online supplementary Appendix).

The interview guide was developed by the study team with the structure recommended by the UK Sepsis Trust “Exemplar Standards for the Emergency Management of Sepsis”.20 It included nine domains: departmental guidelines on sepsis, screening criteria for sepsis, physical location and resources, sepsis care and microbiology, antibiotics availability and antimicrobial guidelines, support from ICU and other departments, factors affecting the level of care provided, priority of audits and research, and training and quality assurance.

One investigator (KH) performed all of the telephone interviews from January to August 2017. Email invitations were sent to the Chiefs of Services of all 18 departments 2 to 3 weeks before the telephone interviews, and all participating departments were asked to provide their prevailing sepsis guidelines (if available) before the telephone interviews. Departments that had not responded were contacted again up to a total of 4 times.

All telephone interviews were audio recorded after obtaining consent. Interview data were recorded using a standardised data collection sheet, and data were entered into an Excel spreadsheet. Descriptive statistics were presented as medians for continuous variables (unless specified otherwise) and percentage proportions for categorical variables. Participants ranked each of the nine barriers to sepsis care using a 5-point Likert scale (‘not important’ 1; ‘slightly important’ 2; ‘important’ 3; ‘fairy important’ 4; and ‘very important’ 5).

Out of the 18 EDs, 16 agreed to participate. One department declined to participate, and one did not respond after repeated contacts.

Seven departments reported the presence of sepsis guidelines in their EDs, with three of these departments using the same regional guidelines. Therefore, five different sets of sepsis guidelines were reported to be in current use across all public EDs in Hong Kong. Table 1 shows the characteristics of the EDs with and without sepsis guidelines. Table 23 21 22 23 24 25 26 summarises the core components of the five sets of guidelines reported. Most of the current versions of the guidelines were implemented between 2014 and 2017.

Four out of the seven departments with sepsis guidelines used qSOFA, which is based on the Sepsis-3 recommendations. Three departments (which used the same regional guidelines) used modified qSOFA criteria. The reasons for this, as reported by respondents, included the concern that replacing the definition of ‘severe sepsis’ with a qSOFA score might increase the number of cases screened as positive. This would result in an increased number of cases requiring management in resuscitation rooms and put further strain on the already scarce ED human resources.

The use of lactate as a biomarker for clinical decision making in sepsis care was uncommon in the surveyed EDs. Fourteen out of the 16 EDs had access to point-of-care testing of blood gases inside the department, but only five had a lactate module. The ED physicians mainly rely on patients’ vital signs and clinical assessment to facilitate recognition of sepsis.

Upon identification of sepsis, two of the EDs’ guidelines explicitly mentioned sending the patient to a resuscitation room (or a bed with intensive monitoring, eg, a high-dependency unit). Most of the surveyed EDs (13 of 16) routinely managed patients with sepsis in their resuscitation rooms. None of the EDs had a designated team or a code specifically for patients with sepsis, unlike the management of major trauma, for which the EDs employed a trauma team approach. One of the EDs had designed a sepsis kit consisting of antiseptic swab sticks and pre-set blood collection tubes and had investigation shortcuts in the computer system to facilitate implementation of the guidelines.

Regarding the resuscitation and stabilisation of patients with sepsis, Table 2 highlights the key areas covered by the existing guidelines. All sets of guidelines refer to the Surviving Sepsis Campaign targets21 22 or the UK Sepsis Six targets.23 All sets of guidelines also mention time to intravenous antibiotics and microbiological workup, including blood cultures, with the majority specifying intravenous antibiotics within 1 hour of the patient’s arrival.

Most EDs (13 of 16) expressed a preference to use normal saline or other isotonic crystalloids for fluid resuscitation. The target volume is up to 20 to 30 mL/kg, with monitoring of the patient’s blood pressure (especially mean arterial pressure) for fluid responsiveness. The use of ultrasonograms was reported to be increasing, especially bedside echocardiograms and inferior vena cava variability, to assess patients’ fluid status. Central venous pressure was mentioned, but its use by ED physicians was perceived to be decreasing in frequency. If vasopressors or inotropes were needed, dopamine was the most common choice, as it can be administered via peripheral veins.

Concerning source identification for sepsis, most sets of guidelines (4 of 5) mentioned chest X-rays and urinalysis. If abdominal sepsis was suspected, some EDs would consult their surgical colleagues and make a joint decision as to when a computed tomography (CT) scan or further imaging may be necessary. Individual departments have large variation in access to CT scans.

All responding EDs reported that antibiotics were stocked in their departments. The numbers of different antibiotics stocked in the EDs ranged from 3 to 18, with a median of 8.5. The choice of antibiotics stocked depended on the individual departments’ antimicrobial guidelines or regional patterns of pathogen and antibiotic resistance. Both the penicillin and cephalosporin groups were present in all EDs, followed in frequency by fluoroquinolones (14 of 16), others (13 of 16), aminoglycosides (12 of 16), carbapenems (9 of 16), and macrolides (2 of 16).

Organ failure and septic shock are frequent indications for ICU admission. However, direct ICU admission of patients with single organ failure from EDs is determined by individual ICU admission policy and bed availability. Support from the ICU and in-patient wards varies across different EDs. During the winter surge and flu seasons, access to hospital beds is reduced, causing both ED congestion and compromised sepsis care, especially for those with stable vital signs or poor premorbid conditions. In some of the surveyed hospitals (4 of 16), laboratory and pharmacy support for sepsis care after office hours is limited. This means that those EDs need to dispense drugs or manage patients without the results of certain laboratory investigations.

In terms of training, audits, and research, most of the surveyed EDs (14 of 16) provided ad hoc training on sepsis management to physicians and nurses, but none had a specific sepsis outcome audit or registry. Even though two local studies18 19 provided some insight into previous sepsis-related mortality, there has been no agreement regarding standardisation of coding or key performance indicators across different departments.

Compared with other time-critical medical emergencies, the respondents perceived sepsis to be the leading cause of in-hospital mortality (average: 4.17), followed by acute coronary syndrome (4.09), stroke (3.00), trauma (2.58), and poisoning (1.08). When the respondents were asked which time-critical emergencies had the highest rates of preventable mortality that was not well managed in the ED, trauma was rated the highest (4.00), followed closely by sepsis (3.42), poisoning (2.92), stroke (2.42), and acute coronary syndrome (2.25). The top barriers to optimal sepsis care in EDs identified by the respondents were lack of knowledge and experience and inadequate nursing human resources, followed by difficulty identifying patients with sepsis. Table 3 lists all of the barriers investigated by the survey and their perceived importance.

In this study, we found varying levels of adoption of international sepsis guidelines among the responding EDs. Sepsis was perceived to be the top cause of in-hospital mortality and the second leading cause of preventable mortality among all time-critical emergencies. Few EDs had adopted the qSOFA score (which is based on the Sepsis-3 recommendations) in patient screening at 1 year after its publication. Early intravenous antibiotic administration within 1 to 2 hours was mandatory according to all of the surveyed EDs’ sepsis guidelines, and all responding EDs reported that antibiotics were stocked within their departments.

Emergency departments across the world have an important responsibility to recognise patients with sepsis, as delays in treatment and administration of antibiotics have been shown to increase in-hospital mortality.27 All responding public EDs had antibiotics available on-site, but few provided clear guidance on which patients might benefit from timely intravenous antibiotic administration except those with neutropenic or post-chemotherapy fever. The widespread availability of intravenous antibiotics across the EDs is likely a result of the recent Hospital Authority review on acute management of neutropenic fever. All of the participating EDs reported the use of either departmental or cluster-wide guidelines for neutropenic fever, and the latest version of the Hospital Authority triage guidelines emphasises the importance of its early recognition and assigns a higher priority to patients with suspected neutropenic fever.28 Despite previous studies in Hong Kong that demonstrated high mortality rates among patients with sepsis without neutropenia,18 19 sepsis generally does not receive the same level of attention as neutropenia in Hong Kong EDs. To improve patient outcomes, more emphasis should be placed on early resuscitation and antibiotic therapy for sepsis in EDs.

Sustained improvement in sepsis care requires not only guidelines but also more resources and staff training. Further, EDs in Hong Kong face many challenges such as access blockages and overcrowding.29 With the rising level of service demand and competing priorities in EDs, it is important to understand the barriers to better sepsis care from health care providers’ perspectives. Our study highlights several challenges. The top barriers reported included a lack of knowledge and experience, nursing human resources shortages, and difficulty identifying patients with sepsis. These findings are similar to those of Carlbom and Rubenfeld,30 who reported a lack of nursing staff, challenges in the identification of patients with sepsis, and problems with central venous pressure monitoring as barriers to optimal sepsis care. For effective changes to take place, it is necessary to overcome these barriers with more staff training, better nursing human resources provision in EDs, elevation of staff awareness of sepsis, and provision of useful bedside tools for sepsis recognition.

The UK Sepsis Six and quality improvement projects in the UK shed light on how sustained reductions in sepsis mortality can be achieved in a publicly funded health system similar to that of Hong Kong.31 In the United States, New York State has required hospitals to follow a sepsis protocol since 2013. Results from 2014 to 2016 showed that 82.5% of patients across 149 hospitals had the 3-hour bundle of care (blood cultures, broad-spectrum antibiotics, and lactate measurement) completed within 3 hours, with a median time to completion of 1.3 hours.32

Steady improvements in survival of other time-critical emergencies including ST elevation myocardial infarction,33 acute ischemic stroke,34 and major trauma35 have been achieved in Hong Kong through systemic changes, more staff training and resources, multidisciplinary collaboration, and regular interdepartmental audits. Regular and systematic data collection from EDs in Hong Kong for monitoring, evaluation of performance and processes of care, and benchmarking is important to assess the impact of various ED sepsis initiatives.

This study has a number of limitations. Not all public EDs in Hong Kong participated in the study. However, we believe that our findings are representative of the current ED processes of sepsis care in Hong Kong. We did not include other private EDs, which might affect the generalisability of our findings; however, ambulances in Hong Kong bring patients to public EDs only, and 90% of all in-patient care is provided by public hospitals. We have likely covered the majority of the EDs in Hong Kong that provide emergency care to patients with sepsis, especially those in critical condition.

Second, it is possible that some respondents might have expressed personal bias when responding to the questions, especially those regarding the barriers to optimal sepsis care. This could have affected the results despite the fact that respondents were reminded that their replies should provide the views of the department (not their personal points of view), and even though the interview guide was shared in advance to consolidate departmental opinions. Individual questionnaires targeting various seniority levels of ED staff might be better to address these questions in the future.

Finally, we relied heavily on the materials provided by the respondents, and their views do not necessarily reflect real clinical practice. However, this provides a beginning to facilitate a better systematic understanding of sepsis care in Hong Kong EDs as a whole. Future studies are warranted to evaluate actual clinical practice, patient outcomes in cases of sepsis, and the impact of adopting new sepsis definitions and international guidelines on a territory-wide basis.

Compared with other time-critical emergencies with high mortality and impact on patients, sepsis has not received adequate attention in Hong Kong EDs. The process of care varies considerably among EDs, and few have departmental sepsis guidelines. With increasing recognition of the burden of sepsis among Hong Kong EDs, more training and resources for management of these patients and the establishment of formal performance indicators should be considered. Systematic routine data collection for prospective multicentre research is needed to improve patient care.

Concept and design: KKC Hung, RPK Lam, RSL Lo, CA Graham.
Acquisition of data: KKC Hung, RPK Lam, MLC Yang, MCK Tai.
Analysis and interpretation of data: KKC Hung, JW Tenney.
Drafting of the article: KKC Hung, RPK Lam.
Critical revision for important intellectual content: All authors.

We thank all of the participants for their time and support of this study.

All authors have disclosed no conflicts of interest. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Ethical approval was obtained from the Survey and Behavioural Research Ethics Committee of the Chinese University of Hong Kong (097-16). Verbal informed consent was obtained from the participants.

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