Comparative burdens of atherosclerosis in rural and urban communities in South India: Insights from the Kovai Medical Center and Hospital-noncommunicable disease studies

Abstract

Aim: The aim of this study was to describe the distribution and comparison of carotid intima thickness in two completely different demographics in South India. Materials and Methods: Data were obtained from 865 participants in rural Nallampatti and 1081 participants from urban Kalapatti in the state of Tamil Nadu. Local ethics committee approval and written and informed consent were obtained from all participants. Carotid intima thickness was measured on all participants using high-resolution B-mode ultrasound. Atherosclerosis was defined as a carotid intima-media thickness of ≥1 mm. Results: The prevalence of atherosclerosis was 10.3% in rural Nallampatti compared to 7.8% in urban Kalapatti. On binary logistic regression analysis, diabetes and hypertension were associated with atherosclerosis in rural areas, but this significance disappeared after adjustment for confounding factors. In urban areas, diabetes appeared to be significantly associated with atherosclerosis even after adjustment for confounding factors. Conclusion: Our data suggest a surprisingly increased prevalence of atherosclerosis in a rural farming population even though traditional risk factors for atherosclerosis such as diabetes and hypertension did not show a significant association after adjustment for confounding factors. If confirmed, this provides a rationale to do large-scale studies to explore the role of nontraditional risk factors in rural India that could have an impact on atherosclerosis and cardiovascular disease.