High prevalence of diabetes and cardiovascular risk factors associated with urbanization in India.

OBJECTIVE To compare prevalence of diabetes, impaired glucose tolerance (IGT), impaired fasting glucose (IFG), and cardiovascular risk factors between a city, a town, and periurban villages (PUVs) in southern India and to look for temporal changes in the city and PUVs. RESEARCH DESIGN AND METHODS Subjects aged >/=20 years were studied in Tamilnadu, India, in Chennai (city, n = 2,192; 1,053 men and 1,138 women), Kanchipuram (town, n = 2,290; 988 men and 1,302 women), and Panruti (PUVs, n = 2,584; 1,280 men and 1,304 women) in 2006. Demographic, socioeconomic, and anthropometric details; blood pressure; physical activity; diet habits; and lipids were studied. Risk associations with diabetes were analyzed using multiple logistic regression analyses. Present and previous data in the city and the PUVs were compared. RESULTS Mean BMI, waist circumference, and family history of diabetes were significantly lower in the PUVs. The PUVs had a lower prevalence of diabetes (9.2 [95% CI 8.0-10.5], P < 0.0001) than the city (18.6 [16.6-20.5]) and town (16.4 [14.1-18.6]). Approximately 40% of subjects were newly diagnosed. Prevalence of impaired glucose tolerance (IGT) was higher (P < 0.0001) in the city (7.4 [6.2-8.5]) than in the town (4.3 [3.3-5.3]) and the PUVs (5.5 [4.6-6.5]). Prevalence of IFG was generally low. Age, family history, and waist circumference were significantly associated with diabetes, while physical activity was not. Overweight, elevated waist circumference, hypertension, and dyslipidemia were more prevalent in the city. CONCLUSIONS In the city, diabetes increased from 13.9 to 18.6% in 6 years and IGT decreased significantly. The town and city had similar prevalences; the PUVs had lower diabetes prevalence, but prevalence had increased compared with that in a previous survey. Cardiometabolic abnormalities were more prevalent in urban populations.