In Pre-Diabetes, Defect Appears Glucose-Specific
Insulin secretion induced by nonglucose nutrients unaffected in early stages of the disease
FRIDAY, April 20 (HealthDay News) -- Although glucose-specific insulin secretion is impaired in patients with pre-diabetes, there seems to be no problem with nonglucose-specific insulin secretion, according to a study in the April issue of Diabetes.
Robert A. Rizza, M.D., of the Mayo Clinic, Rochester, Minn., and colleagues conducted a study of 62 subjects, including 32 with impaired fasting glucose and 30 with normal fasting glucose. The subjects were given either a mixed meal containing 75 g of glucose or 75 g of glucose alone.
In all groups, ingestion of the meal resulted in an increase in insulin secretion that was considered appropriate and resulted in disposition indexes that were the same as, or more than, those during the oral glucose tolerance test. The disposition indexes were lower during the oral glucose tolerance test in the impaired glucose tolerance groups, which indicates that reduced glucose induced insulin secretion.
"We conclude that whereas glucose-induced insulin secretion is impaired in people with abnormal glucose tolerance, nonglucose nutrient-induced secretion is intact, suggesting that a glucose-specific defect in the insulin secretary pathway is an early event in the evolution of type 2 diabetes," the authors concluded.