Weight Loss Therapy Improves Pancreatic Endocrine Function in Obese Older Adults
Open Access
- 1 June 2008
- Vol. 16 (6), 1349-1354
- https://doi.org/10.1038/oby.2008.226
Abstract
Objective: Obesity and aging increase the risk of type 2 diabetes (T2D). We evaluated whether weight loss therapy improves pancreatic endocrine function and insulin sensitivity in obese older adults. Methods and Procedures: Twenty‐four obese (BMI: 38 ± 2 kg/m2) older (age: 70 ± 2 years) adults completed a 6‐month randomized, controlled trial. Participants were randomized to diet and exercise (treatment group) or no therapy (control group). β‐Cell function (assessed using the C‐peptide minimal model), α‐cell function (assessed by the glucagon response to an oral glucose load), insulin sensitivity (assessed using the glucose minimal model), and insulin clearance rate were evaluated using a 5‐h modified oral glucose tolerance test. Results: Body weight decreased in the treatment group, but did not change in the control group (−9 ± 1% vs. 0 ± 1%; P < 0.001). Insulin sensitivity doubled in the treatment group and did not change in the control group (116 ± 49% vs. −11 ± 13%; P < 0.05). Even though indices of β‐cell responsivity to glucose did not change (P > 0.05), the disposition index (DI), which adjusts β‐cell insulin response to changes in insulin sensitivity, improved in the treatment group compared with the control group (100 ± 47% vs. −22 ± 9%; P < 0.05). The glucagon response decreased in the treatment but not in the control group (−5 ± 2% vs. 4 ± 4%; P < 0.05). Insulin secretion rate did not change (P > 0.05), but insulin clearance rate increased (51 ± 25%; P < 0.05), resulting in lower plasma insulin concentrations. Discussion: Weight loss therapy concomitantly improves β‐cell function, lowers plasma glucagon concentrations, and improves insulin action in obese older adults. These metabolic effects are likely to reduce the risk of developing T2D in this population.This publication has 50 references indexed in Scilit:
- Insulin sensitivity by oral glucose minimal models: validation against clampAmerican Journal of Physiology-Endocrinology and Metabolism, 2005
- The Coming Epidemic of Obesity in Elderly AmericansJournal of the American Geriatrics Society, 2004
- Minimal model estimation of glucose absorption and insulin sensitivity from oral test: validation with a tracer methodAmerican Journal of Physiology-Endocrinology and Metabolism, 2004
- Guidelines for Improving the Care of the Older Person with Diabetes MellitusJournal of the American Geriatrics Society, 2003
- The oral glucose minimal model: Estimation of insulin sensitivity from a meal testIEEE Transactions on Biomedical Engineering, 2002
- Minor long‐term changes in weight have beneficial effects on insulin sensitivity and β‐cell function in obese subjectsDiabetes, Obesity and Metabolism, 2002
- Reduced Pancreatic B Cell Compensation to the Insulin Resistance of Aging: Impact on Proinsulin and Insulin LevelsJournal of Clinical Endocrinology & Metabolism, 2000
- The Use of Areas Under Curves in Diabetes ResearchDiabetes Care, 1995
- Postgastroplasty recovery of ideal body weight normalizes glucose and insulin metabolism in obese womenJournal of Clinical Endocrinology & Metabolism, 1995
- Kinetics of insulin internalization and processing in adipocytes: Effects of insulin concentrationJournal of Cellular Physiology, 1989