Special Section: Diabetes

Diabetes mellitus and coronary heart disease are prevalent and predicted to increase sharply in Asian Indians. The data over the last decade suggest that insulin resistance is common in this ethnic group and operates as a ‘common soil’ for development of glucose intolerance and atherosclerosis. Obesity phenotype of Asian Indians; high percent body fat and higher truncal and abdominal fat at a lower lean body mass, may be important in generation of insulin resistance. The metabolic abnormalities significantly associated with insulin resistance in Asian Indians include dyslipidemia (hypertriglyceridemia, low levels of high-density lipoprotein cholesterol and high levels of small-dense low-density lipoprotein), procoagulant tendency, increased proinflammatory cytokines and endothelial dysfunction. Interestingly, such a phenotype and metabolic perturbations are particularly seen in immigrant Asian Indians and also in intracountry migrants from rural areas settled in urban slums. In comparative data including other ethnic groups, Asian Indians had significantly adverse body composition and metabolic profile. Even with the similar amount of body fat, Asian Indians are reported to be more insulin resistant as compared to Caucasians. These data suggest genetic factors in addition to lifestyle and other factors in inducing insulin resistance in Asian Indians. Some of these abnormalities are also evident at young age, particularly in children with low birth weight. Thus, clustering of cardiovascular risk factors and significant insulin resistance are prime factors for early, widespread and severe atherosclerosis in this ethnic group.