ABSTRACT

Hong Kong Med J 2008;14:437-43 | Number 6, December 2008
ORIGINAL ARTICLE
Prevalence and significance of white-coat hypertension and masked hypertension in type 2 diabetics
CM Ng, SF Yiu, KL Choi, CH Choi, YW Ng, SC Tiu
Department of Medicine, Queen Elizabeth Hospital, Kowloon, Hong Kong
 
 
OBJECTIVE. Objectives To explore the prevalence of various categories of hypertension in diabetic patients, and assess any corresponding associations with end-organ complications.
 
DESIGN. Cross-sectional study.
 
SETTING. Tertiary centre of a regional hospital in Hong Kong.
 
PATIENTS. All ambulatory type 2 diabetic patients attending our clinics from January 2002 to November 2004 were invited to participate in the protocol.
 
RESULTS. A total of 133 diabetic patients were included; 82 had normal clinic blood pressures, 15 (18%) of whom had masked hypertension, the remaining 67 (82%) had 'normotension' The remaining 51 patients had high clinic blood pressures, of whom 28 (55%) had white-coat hypertension and 23 (45%) had sustained hypertension. Urinary albumin excretion rate was higher in patients with masked hypertension (10 mg/day; range, 7-580 mg/day) and sustained hypertension (7 mg/day; 7-3360 mg/day) in comparison to those with white-coat hypertension (7 mg/day; 7-109 mg/day) or 'normotension'(7 mg/day; 7-181 mg/day) [P<0.01]. Likewise, the prevalence of albuminuria was significantly higher in patients with masked hypertension (40%) and sustained hypertension (26%) than in those with 'normotension'(6%) and white-coat hypertension (11%) [P<0.01]. The prevalence of left ventricular hypertrophy was significantly higher in subjects with masked hypertension (38%) and sustained hypertension (26%) compared to patients with 'normotension'(8%) or white-coat hypertension (11%) [P<0.01]. Left ventricular diastolic dysfunction was more prevalent in patients with masked hypertension (46%), sustained hypertension (48%), and white-coat hypertension (43%) in comparison to subjects with 'normotension'(18%) [P=0.01].
 
CONCLUSION. Masked hypertension is associated with a higher prevalence of albuminuria, left ventricular diastolic dysfunction, and hypertrophy. White-coat hypertension carries a more benign prognosis than sustained hypertension and masked hypertension. Our cross-sectional study supports the recommendation to performing ambulatory blood pressure measurements in type 2 diabetic patients.
 
Key words: Albuminuria; Blood pressure monitoring, ambulatory; Diabetes mellitus, type 2; Hypertension
 
View this abstract indexed in MEDLINE: