Blood pressure trends, plasma insulin levels and risk factors in rural and urban elderly populations of North India

OBJECTIVE: To compare the prevalence of hypertension and its risk factors with age-specific blood pressures in rural and urban subjects. DESIGN AND SETTING: A cross-sectional survey of two randomly selected villages and 20 randomly selected streets in Moradabad, north India. SUBJECTS AND METHODS: The subjects were 255 rural people (140 men, 115 women) and 311 urban people (172 men, 139 women) aged 60-84 years. The survey methods were questionnaires, blood pressure and anthropometric measurements and electrocardiography. RESULTS: The mean +/- SD blood pressures, both systolic (137.7 +/- 13 versus 131.2 +/- 12 mmHg) and diastolic (89.8 +/- 41 versus 85.8 +/- 9 mmHg) were significantly higher in urban men than they were in rural men. Similar differences between systolic (135.6 +/- 11 versus 129.2 +/- 10 mmHg) and diastolic (90 +/- 10 versus 87.6 +/- 9 mmHg) blood pressures were found among urban and rural women, respectively. A significant correlation between systolic blood pressures and increasing age was observed both for rural and for urban subjects of both sexes. The overall prevalences of hypertension based on World Health Organization criteria (17.6 versus 5.0%) and Joint National Committee fifth report criteria (34.0 versus 10.1%) were significantly higher among urban than they were among rural subjects. Multivariate logistic regression analysis revealed that age, body mass index, central obesity, glucose intolerance, 2 h plasma insulin and triglyceride level were associated independently with hypertension. CONCLUSIONS: The findings indicate that urban subjects had higher blood pressures than did rural subjects and that age, body mass index, central obesity and 2 h plasma insulin levels were significant risk factors for hypertension in an elderly population.