Ethnic disparities in relationship of obesity indices and telomere length in Asians with type 2 diabetes.

BACKGROUND: Obesity and shorter telomeres increase the risk for diabetes complications and mortality. However, the relationship of obesity and telomere length in diverse Asian population with type 2 diabetes (T2D) is not well understood. In this study, we examine the association of the baseline and changes in obesity indices, with telomere length in multi-ethnic Asian populations with T2D.

METHODS: Leukocyte telomere length (LTL) was measured by qPCR assay in SMART2D cohort (n=1431 at baseline, n= 1039 after 3.2 years median follow-up). Associations between obesity indices and LTL were assessed after adjusting for age, gender, diabetes condition, hypertension, obesity and inflammation markers.

RESULTS: Compared to Chinese, LTL was longer in Malays (P<0.0001) and similar in Indians. Cross-sectionally, body mass index (BMI) (β = -0.016, P=0.087), BMI adjusted (residual) visceral fat area (VFA) (β = -0.004, P=0.006) and waist-to-hip ratio (WHR) (β = -1.95, P=0.030) were significantly associated with LTL in Chinese but not in Malays and Indians. Changes in BMI (r= -0.080; P=0.053) and VFA (r= -0.126; P=0.002) were inversely correlated with changes in LTL only in Chinese. Furthermore, 1-SD incremental changes in BMI (β= -0.070; P=0.040) and VFA (β = -0.088, P=0.028) were significantly associated with larger telomere attrition, independent of age, gender, diabetes condition, baseline LTL, obesity and inflammation markers in Chinese.

CONCLUSIONS: 3-year changes in BMI and VFA were associated with telomere dynamics in Chinese but not in Malays and Indians with T2D. Reducing obesity may reduce the risk of diabetes complications associated with shorter LTL, in Chinese population.