Ethnicity and type 2 diabetes - Focus on Asian Indians

Though the overall prevalence of type 2 diabetes is increasing in US and in all other westernized countries, significant differences are noted among d ifferent ethnic groups. The reasons for ethnic differences in the risk of t ype 2 diabetes are not entirely understood. For example, Asian Indians (peo ple from India, Pakistan, and Bangladesh) have remarkably high prevalence o f type 2 diabetes compared to Caucasians. However, the incidence of obesity , an important risk factor in the development of type 2 diabetes, is signif icantly lower in Asian Indians compared to Caucasians. Though westernizatio n of lifestyle with dietary changes and lack or exercise may play a role in increased prevalence of type 2 diabetes in migrant Asian Indians, various epidemiological studies have shown that these factors alone are not suffici ent to explain this trend. One important factor contributing to increased t ype 2 diabetes in Asian Indians is excessive insulin resistance compared to Caucasians. This difference in the degree of insulin resistance may be exp lained by either an environmental or a genetic factor or by combination of both. The understanding of the etiology and mechanisms causing increased in sulin resistance in Asian Indians will provide clues to more effective prev ention and treatment of diabetes in this ethnic group. Furthermore, the inf ormation may help in understanding the pathophysiology of type 2 diabetes i n other ethnic groups and improve methods of treatment and prevention in al l ethnic groups. Since the ethnic mix of the US population is changing rapi dly and it is estimated that by the year 2020, over 50% of US population wi ll include non-Caucasian ethnicity, the identification of the mechanism inv olved in the excessive development of type 2 diabetes in non-Caucasians bec omes important. In this review, possible etiology of excessive insulin resi stance and role or free fatty acids (FFA) in insulin resistance in Asian In dians is discussed. Finally, the role of targeting insulin resistance in pr evention and treatment or diabetes is discussed. (C) 2001 Elsevier Science Inc. All rights reserved.