Changes in Insulin Secretion and Insulin Sensitivity in Relation to the Glycemic Outcomes in Subjects With Impaired Glucose Tolerance in the Indian Diabetes Prevention Programme-1 (IDPP-1)

• Published in: Diabetes care Vol. 32; no. 10; pp. 1796 - 1801
• Main Authors: Snehalatha, Chamukuttan, Mary, Simon, Selvam, Sundaram, Sathish Kumar, Cholaiyil Kizhakathil, Shetty, Samith Babu Ananth, Nanditha, Arun, Ramachandran, Ambady
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.10.2009
• Subjects: Adult; Analysis; anthropometric measurements; Biological and medical sciences; blood glucose; Changes; Dextrose; Diabetes; Diabetes Mellitus, Type 2; Diabetes Mellitus, Type 2 - drug therapy; Diabetes Mellitus, Type 2 - metabolism; Diabetes Mellitus, Type 2 - prevention & control; Diabetes Mellitus, Type 2 - therapy; Diabetes. Impaired glucose tolerance; drug therapy; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; fasting; Female; Glucose; Glucose Intolerance; Glucose Intolerance - drug therapy; Glucose Intolerance - physiopathology; glucose tolerance; homeostasis; Humans; Hypoglycemic Agents; Hypoglycemic Agents - therapeutic use; Insulin; Insulin - metabolism; insulin resistance; Insulin Resistance - physiology; Insulin Secretion; Intervention; lifestyle; Male; Medical sciences; Metabolic diseases; metabolism; metformin; Metformin - therapeutic use; Middle Aged; Minority & ethnic groups; Miscellaneous; Original Research; physiology; physiopathology; Plasma; prevention & control; Public health. Hygiene; Public health. Hygiene-occupational medicine; risk; secretion; Statistical analysis; Studies; therapeutic use; therapy; Treatment Outcome; Asia; India; Endocrinopathy; Human; Sanitary program; Pancreatic hormone; Prognosis; Nutrition; Secretion; Insulin sensitivity; Diabetes mellitus; Metabolic diseases; Change; Insulin; Prevention; Evolution; Indian; Impaired glucose tolerance; Endocrinology; Glycemia
• ISSN: 0149-5992; 1935-5548; 1935-5548
• DOI: 10.2337/dc09-0676

OBJECTIVE: The Indian Diabetes Prevention Programme-1 (IDPP-1) showed that lifestyle modification (LSM) and metformin were effective for primary prevention of diabetes in subjects with impaired glucose tolerance (IGT). Among subjects followed up for 3 years (n = 502), risk reductions versus those for the control group were 28.5, 26.4, and 28.2% in LSM, metformin (MET), and LSM plus MET groups, respectively. In this analysis, the roles of changes in secretion and action of insulin in improving the outcome were studied. RESEARCH DESIGN AND METHODS: For this analysis, 437 subjects (93 subjects with normoglycemia [NGT], 150 subjects with IGT, and 194 subjects with diabetes) were included. Measurements of anthropometry, plasma glucose, and plasma insulin at baseline and at follow-up were available for all of them. Indexes of insulin resistance (homeostasis model assessment of insulin resistance) and β-cell function (insulinogenic index [ΔI/G]: 30-min fasting insulin divided by 30-min glucose) were also analyzed in relation to the outcome. RESULTS: Subjects with IGT showed a deterioration in β-cell function with time. Individuals with higher insulin resistance and/or low β-cell function at baseline had poor outcome on follow-up. In relation to no abnormalities, the highest incidence of diabetes occurred when both abnormalities coexisted (54.9 vs. 33.7%, χ² = 7.53, P = 0.006). Individuals having abnormal insulin resistance (41.1%) or abnormal ΔI/G (51.2%, χ² = 4.87, P = 0.027 vs. no abnormalities) had lower incidence. Normal β-cell function with improved insulin sensitivity facilitated reversal to NGT, whereas deterioration in both resulted in diabetes. The beneficial changes were better with intervention than in the control group. Intervention groups had higher rates of NGT and lower rates of diabetes. CONCLUSIONS: In the IDPP-1 subjects, beneficial outcomes occurred because of improved insulin action and sensitivity caused by the intervention strategies.