Review: Type 2 diabetes in India: regional disparities

Abstract

Type 2 diabetes mellitus epidemic in India is a result of societal influences and changing lifestyles. Diabetes has been known in India for centuries as a disease of the affluent class. Epidemiological studies in the 1960's and 1970's using random and post-load blood glucose estimations reported diabetes prevalence varying from 1—4% in urban populations and 1—2% in rural populations. More standardised epidemiological studies since the 1990's reported prevalence rates that vary from 5—15% among urban populations, 4—6% in semi-urban populations and 2—5% in rural populations with large location-based disparities within urban and rural populations. There is a significantly increasing trend in urban populations (exponential trend R2=0.744) while among rural populations the prevalence is increasing at a slower rate (R²=0.289). At the turn of this century diabetes in adult urban Indian populations varies from a low of 5.4% in a northern state to a high of 12.3—15.5% in Chennai, South India, and 12.3—16.8% in Jaipur, Central India. This scenario is similar to other South Asian countries and evolving populations in East Asia, Middle-East, Americas, Australasia and Pacific Islands. Gene-environment interactions appear to be responsible for this rapid increase. The insulin-resistant state that was meant to be protective mechanism for regulation of calorie and fat metabolism at times of famine has turned deleterious as affluence has increased among these populations leading to diabetes epidemic. Population based measures to prevent the control of a diabetes epidemic include avoidance of adiposity by enhanced physical activity and regulated calorie intake.