Objective: To test the hypothesis that high prevalences of cardiovascular disease and diabetes in urban population of India are manifestations of insulin-resistance syndrome.
Design and setting: Cross-sectional surveys were conducted in 20 streets in the city of Moradabad and in two villages.
Subjects and methods: There were 566 subjects (255 rural and 311 urban) aged 60-84 years. All subjects were divided on the basis of their insensitivity to insulin into groups with mild, moderate and high insensitivity to insulin and data from both sexes were pooled for analysis.
Results: Overall increases in the prevalences of coronary disease, diabetes, hypertension, central obesity and associated disturbances were observed with increasing insensitivity to insulin and the trend was more significant among urban than it was among rural subjects. Multivariate logistic regression analysis revealed a significant positive association of level of insulin insensitivity with the age-adjusted prevalences of coronary disease, hypertension, diabetes, hypertriglyceridaemia, intolerance of glucose and central obesity among urban subjects. We observed a significant inverse association between insensitivity to insulin and physical activity both for rural and for urban subjects and between insensitivity to insulin and high-density lipoprotein cholesterol level for urban subjects. For rural subjects, we found significant associations of sensitivity to insulin with coronary artery disease and intolerance of glucose without significant associations with other risk factors.
Conclusion: Insensitivity to insulin was significantly associated with risks of cardiovascular disease and diabetes, despite there being a low prevalence of obesity (9.0%) among urban subjects. Hypertension, diabetes, hypertriglyceridaemia, intolerance of glucose and central obesity were significantly associated with insensitivity to insulin and coronary disease for urban but not for rural people.