The frequency in the population now is approaching 8%, up from about 5% a decade ago. >Diabetes incidence is expanding to epidemic proportions. It is a leading cause of heart attacks and stroke as well as microvascular complications along with blindness and kidney failure," according to Dr. Ronald B. Goldberg, MD, from the University of Miami, FL, USA.
Major public health decisions need to be made in treating impaired glucose tolerance (IGT) to prevent type 2 diabetes. Patients with a long period of glucose intolerance have a 10-fold increased risk for developing diabetes. Identifying IGT presents an optimal time for early intervention, hence the durability and safety of treatment options should be considered.
Dr. Goldberg, a professor of medicine in the Division of Endocrinology, Diabetes and Metabolism and Director, Lipid Disorders Clinic at University of Miami, FL, USA, spoke February 15th at the Pri-Med South Conference.
Glucose intolerance initially presents with normal blood sugar. Eventually, insulin secretion decreases due to beta cell dysfunction, at which time postprandial and fasting tests will uncover impairment of blood-glucose secretion, signaling the presence of diabetes.
Strategies that may prevent progression to diabetes include weight reduction, exercise, insulin secretagogues, metformin, glucosidase inhibitors, and thiazolidinedione.
The Diabetes Prevention Program, with more than 3000 participants in 26 centers, tested patients with impaired glucose tolerance at 6-month intervals. Diabetes risk was reduced by 31% among patients who were treated with metformin (which tends to restrain weight gain) and by 58% for patients who improved their lifestyle, Dr. Goldberg observed. Losing even 5-7 kg has "an enormous benefit" that was also apparent in cholesterol levels and other cardiovascular risk-factor reductions, he said.
The Finnish Diabetes Prevention Study, which followed patients diagnosed with impaired glucose tolerance, similarly found that risk of diabetes was reduced by 58% in patients exhibiting lifestyle changes, Goldberg reported.
Last year’s Study to Prevent Non-Insulin Dependent Diabetes Mellitus (STOP NIDDM) treated patients with acarbose. The researchers observed a 25% risk reduction for diabetes and hypertension risk was also reduced by 5%-6%, he added.
The Troglitazone in Prevention of Diabetes (TRIPOD) study, which treated patients with troglitazone before it was withdrawn from the market in the United States, achieved a 56% reduction in diabetes risk, Goldberg noted. Patients who had the most benefit were those who had less pancreatic dysfunction at baseline. The effects of troglitazone were sustained even after the drug was discontinued.
The Xenical in the Prevention of Diabetes in Obese Subjects (XENDOS) study treated obese patients with impaired glucose tolerance with the weight-loss agent Xenical (orlistat). Risk reduction for diabetes was reduced by 37% although Xenical has no apparent effect on the pancreas, Dr. Goldberg said.