Ethnic differences in the prevalence of diabetes in underweight and normal weight individuals: The CARRS and NHANES studies

Abstract

Aims: Type 2 diabetes in lean individuals has recently come to attention. We assessed type 2 diabetes prevalence and the associated risk factors in underweight and normal weight individuals in two ethnic populations. Methods: We conducted cross-sectional analyses, using representative samples of 4,930 Asian Indians from the CARRS-Chennai Study and 2,868 Whites from the NHANES Survey. Diabetes was defined as use of glucose lowering medication, fasting glucose ≥ 126 mg/dl, or 2 hour glucose ≥ 200 mg/dl. Body mass index (BMI) was classified using WHO standard criteria. Results: Prevalence of type 2 diabetes by BMI varied by ethnicity and sex. In men, type 2 diabetes prevalence was 5.4% and 23.5% in underweight and normal weight Asian Indians and 0.0% and 6.1% in underweight and normal weight Whites. In women, the prevalence was 5.6% and 13.6% in underweight and normal weight Asian Indians and 2.3% and 2.8% in underweight and normal weight Whites. Adjustment for waist circumference, insulin resistance, and insulin secretion did not explain the increased prevalence in Asian Indians. Conclusions: These findings suggest significant ethnic differences in type 2 diabetes prevalence without overweight or obesity. Future studies should examine the pathophysiology of type 2 diabetes development in lean individuals.

Diabetes in Normal-Weight Individuals: High Susceptibility in Nonwhite Populations

“…In conclusion, the article from Zhu et al (5) details a substantial burden of diabetes at nonobese levels of BMI in all populations, but especially in racial/ ethnic minorities in the U.S. These results echo previous studies pointing to a high prevalence of diabetes in normal-weight groups in nonwhite populations, both in high-and low-income settings (2,(23)(24)(25). Given that the largest increases in diabetes prevalence are expected in nonobese, nonwhite individuals (1), who represent the majority of the world, it is important to understand the factors other than obesity driving risk posed in this sizable population.…”

Prevalence, incidence and predictors of cardiovascular risk factors: longitudinal data from rural and urban South India and comparison with global data

“…Asian Indians develop hypertension, T2D, and CVD at a younger age compared with other ethnic groups. 13 14 Similarly, a high prevalence of these CVD risk factors at relatively low levels of BMI has been recognized for several decades. 15 Reasons for this remain unclear and could reflect greater genetic/epigenetic susceptibility and/or other causal factors.…”

Tale of two Indians: Heterogeneity in type 2 diabetes pathophysiology

“…Stefan and colleagues showed that from a study of nearly 1000 Caucasian subjects stratified by BMI categories, 18% of the 181 normal weight subjects were metabolically unhealthy, and the most prevalent risk phenotype was insulin secretion failure . In a separate study examining normal weight US adults, 21.0% of non‐Hispanic whites, 31.1% of African Americans, 38.5% of Hispanics, and 43.6% of South Asians were metabolically unhealthy yet thin, and South Asians had poorer pancreatic beta‐cell function compared with whites, blacks, and Hispanics . Similarly, an analysis from the Whitehall II cohort study in the UK suggested that South Asians may have a poorer beta‐cell reserve relative to white Europeans .…”