Prevalence and risk factors of peripheral vascular disease in a selected South Indian population - The Chennai urban population study

OBJECTIVE - The epidemiology of peripheral vascular disease has rarely been studied in non-European populations. The purpose of this study was to determine the prevalence and risk factors of peripheral vascular disease (PVD) among South Indians. RESEARCH DESIGN AND METHODS - The Chennai Urban Population Study is an epidemiological study involving 2 residential areas in Chennai in South India. Of the 1,399 eligible subjects (greater than or equal to 20 years of age), 1,262 (90.2%) participated in the study. All of the study subjects underwent an oral glucose tolerance test and were categorized as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or diabetes. Peripheral Doppler studies were performed on 50% of the study subjects, and PVD was defined as an ankle-brachial index (ABI) <0.9. RESULTS - The prevalence rates of PVD were 2.7, 2.9, and 6.3% in individuals with NGT, IGT, and diabetes, respectively. The overall prevalence rate was 3.2%. Known diabetic subjects had a higher prevalence of PVD (7.8%) compared with newly diagnosed diabetic subjects (3.5%). PVD was uncommon until middle-age and then the prevalence rate increased dramatically. Univariate regression analysis showed age >50 years (odds ratio [OR] 6.3, 95% CI 2.1-20.6, P < 0001) and hypertension (OR 2.7, 0.9-7.3, P = 0.08) to be associated with PVD, whereas smoking and serum lipid levels showed no association. Multivariate regression analysis identified age at the most significant risk factor for PVD. Of the 90 subjects who had coronary artery disease (CAD), only 6 had PVD, and the positive predictive value of the ABI for CAD was only 30%. CONCLUSIONS - The prevalence of PVD in this urban South Indian population is considerably lower than that reported in European and U.S. studies and is in marked contrast to the high prevalence rate of CAD reported in this population.