Relationship between the metabolic syndrome and the development of hypertension in the Hong Kong Cardiovascular Risk Factor Prevalence Study-2 (CRISPS2).
BACKGROUND
The metabolic syndrome is a predictor of diabetes and coronary events. We hypothesized that it also predicts hypertension.


METHODS
A total of 1,944 subjects (901 men and 1,043 women; age 46 +/- 12 years) from the Hong Kong Cardiovascular Risk Factor Prevalence Survey were recruited in 1995-1996 and restudied in 2000-2004. The prevalence of hypertension and factors predicting its development were determined.


RESULTS
In 2000-2004, hypertension was found in 23.2% of the men and 17.2% of the women. Of the 1,602 subjects who were normotensive at baseline, 258 subjects developed hypertension after a median interval of 6.4 years. According to the National Cholesterol Education Program (NCEP) and International Diabetes Federation (IDF) criteria, the hazard ratios associated with the metabolic syndrome were 1.89 (95% confidence interval (CI): 1.41-2.54) and 1.72 (95% CI: 1.24-2.39), respectively. The positive and negative predictive values of the metabolic syndrome for identifying subjects who will develop hypertension in this population were 34.7 and 85.4% (NCEP criteria), and 33.1 and 85.5% (IDF criteria), respectively. The development of hypertension was related to the number of components of the metabolic syndrome (other than raised blood pressure), present in men (P = 0.003) and in women (P = 0.001). Using multivariate analysis, age, baseline systolic blood pressure (SBP), body mass index (BMI), and the triglycerides/high-density lipoprotein (HDL) ratio were found to be significant predictors of the development of hypertension. Compared with optimal blood pressure, the hazards of developing hypertension associated with normal or high-normal blood pressure were 2.31 (95% CI: 1.68-3.17) and 3.48 (95% CI: 2.52-4.81), respectively.


CONCLUSIONS
Blood pressure, when not optimal, is the predominant predictor of hypertension. The metabolic syndrome contributes to the risk, especially when blood pressure is optimal.
Cheung
Bernard M Y
BM
Department of Medicine, University of Hong Kong, Hong Kong. b.cheung@bham.ac.uk
Wat
Nelson M S
NM
Man
Y B
YB
Tam
Sidney
S
Cheng
C H
CH
Leung
Gabriel M
GM
Woo
Jean
J
Janus
Edward D
ED
Lau
C P
CP
Lam
T H
TH
Lam
Karen S L
KS
D000328:Adult; D000367:Age Factors; D000368:Aged; D001794:Blood Pressure; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D006306:Health Surveys; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D008055:Lipids / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000453:epidemiology; D015995:Prevalence; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
D008055:Lipids