Yu Bun Man

Detection of hypertension and blood pressure control are critically important for reducing the risk of heart attacks and strokes. We analyzed the trends in the prevalence, awareness, treatment, and control of hypertension in the United States in the period 1999-2004. We used the National Health and Nutrition Examination Survey 1999-2004 database. Blood pressure information on 14 653 individuals (4749 in 1999-2000, 5032 in 2001-2002, and 4872 in 2003-2004) aged >or=18 years was used. Hypertension was defined as blood pressure >or=140/90 mm Hg or taking antihypertensive medications. The prevalence of hypertension in 2003-2004 was 7.3+/-0.9%, 32.6+/-2.0%, and 66.3+/-1.8% in the 18 to 39, 40 to 59, and >or=60 age groups, respectively. The overall prevalence was 29.3%. When compared with 1999-2000, there were nonsignificant increases in the overall prevalence, awareness, and treatment rates of hypertension. The blood pressure control rate was 29.2+/-2.3% in 1999-2000 and 36.8+/-2.3% in 2003-2004. The age-adjusted increase in control rate was 8.1% (95% CI: 2.4 to 13.8%; P=0.006). The control rates increased significantly in both sexes, non-Hispanic blacks, and Mexican Americans. Among the >or=60 age group, the awareness, treatment, and control rates of hypertension had all increased significantly (P<or=0.01). The improvement in blood pressure control is encouraging, although the prevalence of hypertension has not declined.

OBJECTIVES: Urotensin II is the most potent vasoconstrictor known. Its role in hypertension has not been investigated. Here, we studied the plasma levels in hypertensive and normotensive human subjects. DESIGN: A cross-sectional case-control study. SETTING: Hypertension clinic and research clinic of a university teaching hospital. PARTICIPANTS: Sixty-two hypertensive outpatient subjects (52% male, aged 57 +/- 13 years) and 62 normotensive controls (45% male, aged 54 +/- 13 years) recruited from the general population. MAIN OUTCOME MEASURES: Plasma urotensin II levels measured by radioimmunoassay, systolic and diastolic blood pressure. RESULTS: Plasma urotensin II was 8.8 +/- 0.9 pmol/l in normotensive controls and 13.6 +/- 1.4 pmol/l in hypertensive subjects (P = 0.005). In multiple regression analysis, systolic blood pressure was related to plasma urotensin II (beta = 0.31, P < 0.001) and age (beta = 0.28, P = 0.001), accounting for 10 and 8%, respectively, of the variance in systolic blood pressure. There was no significant correlation with gender, renal function or diabetes. CONCLUSIONS: Plasma urotensin II was raised in hypertensive patients compared to normotensive controls, and was directly related to systolic blood pressure. Our findings raise the possibility that urotensin II may have an aetiological role in hypertension and its complications.

OBJECTIVE: We investigated the association of the metabolic syndrome with new-onset diabetes in the Hong Kong Cardiovascular Risk Factor Prevalence Study cohort. RESEARCH DESIGN AND METHODS: We followed up on 1,679 subjects without diabetes at baseline. Those with a previous diagnosis of diabetes or those who were receiving drug treatment were considered to be diabetic. The remaining subjects underwent a 75-g oral glucose tolerance test (OGTT). Diabetes was defined by plasma glucose > or =7.0 mmol/l with fasting and/or > or =11.1 mmol/l at 2 h. RESULTS: The prevalences of the metabolic syndrome at baseline were 14.5 and 11.4%, respectively, according to U.S. National Cholesterol Education Program (NCEP) and International Diabetes Federation (IDF) criteria. After a median of 6.4 years, there were 66 and 54 new cases of diabetes in men and women, respectively. The metabolic syndrome at baseline predicted incident diabetes. Hazard ratios (HRs) for the NCEP and IDF definitions of the syndrome were 4.1 [95% CI 2.8-6.0] and 3.5 [2.3-5.2], respectively. HRs for fasting plasma glucose (FPG) > or =6.1 or 5.6 mmol/l were 6.9 [4.1-11.5] and 4.1 [2.8-6.0], respectively. The NCEP and IDF criteria had 41.9 and 31.7% sensitivity and 87.5 and 90.2% specificity, respectively. Their positive predictive values were low, approximately 20%, but their negative predictive values were approximately 95%. CONCLUSIONS: The metabolic syndrome, particularly its component, elevated FPG, predicts diabetes in Chinese. An individual without the metabolic syndrome is unlikely to develop diabetes, but one who has it should practice therapeutic lifestyle changes and have periodic FPG measurements to detect new-onset diabetes.

The prevalence, awareness, treatment, and control of hypertension in the United States are analyzed using the National Health and Nutrition Examination Survey (NHANES) database covering the period 1988-2002. Mean body mass index was 26.1+/-0.1 kg/m2 in 1988-1991 and 27.9+/-0.2 kg/m2 in 2001-2002 (p < 0.001). In the same period, the prevalence of diabetes mellitus increased from 5.0% to 6.5% (p = 0.03). Diastolic blood pressure was 73.3+/-0.2 mm Hg in 1988-1991 and 71.6+/-0.4 mm Hg in 2001-2002 (p < 0.001). Among the 18-39 years and 60 years and older age groups, the prevalence of hypertension increased significantly since 1988-1991. Multiple regression shows age, body mass index, and being non-Hispanic black were significantly associated with hypertension. In the period 1988-2002, the percentage receiving treatment and the percentage with blood pressure controlled increased significantly. In 2001-2002, significantly more people with hypertension and diabetes reached a blood pressure target of <130/85 mm Hg. Overall, the control rates were low, especially among middle-aged Mexican-American men (8%).

The authors studied the prevalence of the metabolic syndrome in the 1999-2002 National Health and Nutrition Examination Survey (NHANES) according to the World Health Organization, National Cholesterol Education Program (NCEP), and International Diabetes Federation (IDF) definitions. There was 92.9% agreement between the NCEP and IDF definitions. The IDF prevalence was higher (p = 0.001) due to more men fulfilling its criteria than the NCEP's (39.9 +/- 1.7% vs. 33.6 +/- 1.6%; p = 0.007). If central obesity were not a prerequisite, the IDF prevalence would increase slightly to 40.3 +/- 1.1%. Subjects categorized as having the metabolic syndrome under IDF but not NCEP tended to be men, younger, and leaner. Their prevalence of self-reported coronary heart disease was not significantly different from that of other metabolic syndrome patients. Whether waist circumference is a prerequisite does not affect the diagnosis of the metabolic syndrome in the United States. The IDF definition identifies additional individuals at risk for cardiovascular disease.