Glucose intolerance, hyperinsulinemia and insulin resistance in aplastic anemia

Oral glucose tolerance tests were conducted in 29 patients with aplastic anemia and 20 nondiabetic controls. Seventeen were men and 12 were women, ranging in age from 15 to 67 years. Based on the results of oral glucose tolerance test, the patients were divided into three groups: 14 previously treated cases with normal glucose tolerance; eight previously treated cases with abnormal glucose tolerance, of whom six had diabetes and two had impaired glucose tolerance; and seven newly diagnosed cases with normal glucose tolerance. Hyperinsulinemia and insulin resistance were observed in all patients. Multivariate analyses show that sex, age, body mass index, previous androgen and corticosteroid therapy, previous blood transfusion, initial hemoglobin and white blood cell and serum ferritin concentrations were not significantly related to hyperinsulinemia as expressed by the integrated insulin area under the curve of glucose tolerance test. Patients in the second group who had abnormal glucose tolerance had a delay in insulin secretion in response to glucose, indicating a deterioration of insulin reserve in the beta cells. Patients in this group were significantly older at the time of diagnosis than those in the first group. No other determinants of the development of abnormal glucose tolerance were demonstrated.