Evidence of Reduced -Cell Function in Asian Indians With Mild Dysglycemia

• Type of Material: Article
• Authors: Lisa Staimez, Emory University; Mary Weber, Emory University; Harish Ranjani, Madras Diabetes Research Foundation; Mohammed Ali, Emory University; Justin B. Echouffo-Tcheugui, Emory University; Lawrence Phillips, Emory University; Viswanathan Mohan, Madras Diabetes Research Foundation; Kabayam Venkat Narayan, Emory University
• Language: English
• Date: 2013-09-01
• Publisher: American Diabetes Association
• Publication Version: Final Published Version
• Copyright Statement: © 2013 by the American Diabetes Association.
• License: Creative Commons Attribution 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.2337/dc12-2290
• Title of Journal or Parent Work: Diabetes Care
• ISSN: 0149-5992
• Volume: 36
• Issue: 9
• Start Page: 2772
• End Page: 2778
• Grant/Funding Information: This project also was supported by Emory Global Health Institute, Molecules to Humankind Program sponsored by the Burroughs Wellcome Fund (L.R.S), the National Institutes of Health T32 grant (5T32DK007298-33 to M.B.W), VA award HSR&D IIR 07-138 (L.S.P. and K.M.V.N.), and Cystic Fibrosis Foundation award PHILLI12A0 (L.S.P.).; The project is supported by a BRiDGES grant from the International Diabetes Federation. BRiDGES, an International Diabetes Federation project, is supported by an educational grant from Lilly Diabetes.
• Keywords: Endocrinology & Metabolism; SECRETION; INSULIN-RESISTANCE; TYPE-2 DIABETES-MELLITUS; ENDOCRINOLOGY & METABOLISM; Science & Technology; FASTING GLUCOSE; IMPAIRED GLUCOSE-TOLERANCE; ORAL DISPOSITION INDEX; Life Sciences & Biomedicine; DEFECTS; CHINESE MAURITIANS; PLASMA-GLUCOSE; SENSITIVITY
• Research Categories: Health Sciences, Public Health; Health Sciences, Epidemiology; Health Sciences, Immunology

Abstract

OBJECTIVE-To examine β-cell function across a spectrum of glycemia among Asian Indians, a population experiencing type 2 diabetes development at young ages despite low BMI. RESEARCH DESIGN AND METHODS-One-thousand two-hundred sixty-four individuals without known diabetes in the Diabetes Community Lifestyle Improvement Program in Chennai, India, had a 75-g oral glucose tolerance test,with glucose and insulinmeasured at 0, 30, and 120 min. Type 2 diabetes, isolated impaired fasting glucose (iIFG), isolated impaired glucose tolerance (iIGT), combined impaired fasting glucose and impaired glucose tolerance, and normal glucose tolerance (NGT) were defined by American Diabetes Association guidelines. Measures included insulin resistance and sensitivity (homeostasis model assessment of insulin resistance [HOMA-IR], modified Matsuda Index, 1/fasting insulin) and β-cell function (oral disposition index = [Δinsulin0-30/Δglucose0-30] × [1/fasting insulin]). RESULTS-Mean age was 44.2 years (SD, 9.3) and BMI 27.4 kg/m 2 (SD, 3.8); 341 individuals had NGT, 672 had iIFG, IGT, or IFG plus IGT, and 251 had diabetes. Patterns of insulin resistance or sensitivity were similar across glycemic categories. With mild dysglycemia, the absolute differences in age- and sex-adjusted oral disposition index (NGT vs. iIFG, 38%; NGT vs. iIGT, 32%) were greater than the differences in HOMA-IR (NGT vs. iIFG, 25%; NGT vs. iIGT, 23%; each P < 0.0001). Compared with NGT and adjusted for age, sex, BMI, waist circumference, and family history, the odds of mild dysglycemia were more significant per SD of oral disposition index (iIFG: odds ratio [OR], 0.36; 95% CI, 0.23-0.55; iIGT: OR, 0.37; 95% CI, 0.24-0.56) than per SD of HOMA-IR (iIFG: OR, 1.69; 95% CI, 1.23-2.33; iIGT: OR, 1.53; 95% CI, 1.11-2.11). CONCLUSIONS-Asian Indians with mild dysglycemia have reduced β-cell function, regardless of age, adiposity, insulin sensitivity, or family history. Strategies in diabetes prevention should minimize loss of β-cell function.