RT Journal Article
SR Electronic
T1 Incidence and pathophysiology of diabetes in South Asian adults living in India and Pakistan compared with US blacks and whites
JF BMJ Open Diabetes Research & Care
JO BMJ Open Diab Res Care
FD American Diabetes Association
SP e001927
DO 10.1136/bmjdrc-2020-001927
VO 9
IS 1
A1 K M Venkat Narayan
A1 Dimple Kondal
A1 Natalie Daya
A1 Unjali P Gujral
A1 Deepa Mohan
A1 Shivani A Patel
A1 Roopa Shivashankar
A1 Ranjit Mohan Anjana
A1 Lisa R Staimez
A1 Mohammed K Ali
A1 Howard H Chang
A1 Masood Kadir
A1 Dorairaj Prabhakaran
A1 Elizabeth Selvin
A1 Viswanathan Mohan
A1 Nikhil Tandon
YR 2021
UL http://drc.bmj.com/content/9/1/e001927.abstract
AB Introduction We compared diabetes incidence in South Asians aged ≥45 years in urban India (Chennai and Delhi) and Pakistan (Karachi), two low-income and middle-income countries undergoing rapid transition, with blacks and whites in the US, a high-income country.Research design and methods We computed age-specific, sex-specific and body mass index (BMI)-specific diabetes incidence from the prospective Center for Cardiometabolic Risk Reduction in South Asia Study (n=3136) and the Atherosclerosis Risk in Communities Study (blacks, n=3059; whites, n=9924). We assessed factors associated with incident diabetes using Cox proportional hazards regression.Results South Asians have lower BMI and waist circumference than blacks and whites (median BMI, kg/m2: 24.9 vs 28.2 vs 26.0; median waist circumference, cm 87.5 vs 96.0 vs 95.0). South Asians were less insulin resistant than blacks and whites (age-BMI-adjusted homeostatic model assessment of insulin resistance, µIU/mL/mmol/L: 2.30 vs 3.45 vs 2.59), and more insulin deficient than blacks but not whites (age-BMI-adjusted homeostasis model assessment of β-cell dysfunction, µIU/mL/mmol/L: 103.7 vs 140.6 vs 103.9). Age-standardized diabetes incidence (cases/1000 person-years (95% CI)) in South Asian men was similar to black men and 1.6 times higher (1.37 to 1.92) than white men (26.0 (22.2 to 29.8) vs 26.2 (22.7 to 29.7) vs 16.1 (14.8 to 17.4)). In South Asian women, incidence was slightly higher than black women and 3 times (2.61 to 3.66) the rate in white women (31.9 (27.5 to 36.2) vs 28.6 (25.7 to 31.6) vs 11.3 (10.2 to 12.3)). In normal weight (BMI <25 kg/m2), diabetes incidence adjusted for age was 2.9 times higher (2.09 to 4.28) in South Asian men, and 5.3 times (3.64 to 7.54) in South Asian women than in white women.Conclusions South Asian adults have lower BMI and are less insulin resistant than US blacks and whites, but have higher diabetes incidence than US whites, especially in subgroups without obesity. Factors other than insulin resistance (ie, insulin secretion) may play an important role in the natural history of diabetes in South Asians.