1597-P: Incidence of Diabetes in Young Adult South Asians Compared with Pima Indians

South Asians have a high burden of diabetes at younger ages. We compared diabetes risk in South Asians aged 20-44 years living in India (Delhi and Chennai) and Pakistan (Karachi) with Pima Indians, a population with the world’s highest incidence of diabetes. We analyzed prospective cohort data from the Pima Indian Study (Pima, n=1852), and the Center for Cardiometabolic Risk Reduction in South Asia Study (CARRS, South Asians, n=6676). We defined diabetes as fasting glucose ≥126 mg/dl, HbA1c ≥ 6.5%, or medication use. At baseline, on average, the South Asians were less obese than Pima (BMI, kg/m2: 24.4 vs. 33.8; Waist, cms 82.5 vs.107). Age-standardized diabetes incidence (cases/1000 person-years, 95% CI) was lower in South Asians than in Pima (Men: 14.2, 12.2-16.2 vs. 37.3, 31.8-42.8; Women: 14.8, 13.0-16.5 vs. 46.1, 41.2-51.1). Incidence among 20-24 year old were 80% and 87% lower, respectively, among South Asian men and women, but the risk differential narrowed at older ages (Table). In those with BMI <25 kg/m2, the risk of diabetes was over five times higher in South Asian men than in Pima. Among those with BMI ≥30 kg/m2, diabetes incidence in South Asians was nearly as high as in Pima. Intriguingly, diabetes incidence is higher in nonobese South Asian than in Pima men but not in women. In obese South Asians, diabetes incidence is perilously close to that in the Pima, and is a cause for major concern, as obesity levels continue to rise in South Asia. Disclosure K. Narayan: None. D. Kondal: None. S. Kobes: None. M. Deepa: None. N.R. Daya: None. S.A. Patel: None. R. Anjana: None. L.R. Staimez: None. M.K. Ali: None. U. Gujral: None. D. Prabhakaran: None. R. Shivashankar: None. M. Kadir: None. E. Selvin: None. V. Mohan: None. R.L. Hanson: None. N. Tandon: None. Funding National Heart, Lung, and Blood Institute; Department of Health and Human Services (HHSN268200900026C); United Health Group, Minneapolis, MN; National Institute of Diabetes and Digestive and Kidney Diseases (P30DK111024)