Mechanism and significance of carbohydrate intolerance in chronic alcoholism

Intravenous glucose tolerance tests were carried out in 61 chronic alcoholic patients, divided into two groups, and in a third group consisting of healthy, nonalcoholic volunteers. Members of one experimental group were drinking alcohol throughout the study. The patients of the other experimental group received no alcohol and were in withdrawal from alcohol. The glucose tolerance tests were carried out on each patient on admission to the hospital and 1 wk later. During the test, blood was drawn at 10 min intervals for glucose, immunoreactive insulin, and glucagon determinations. The results indicated that there was transient carbohydrate intolerance in the great majority of both patient groups, and it became evident that the carbohydrate intolerance was the result of continuous alcohol consumption and was not part of the withdrawal syndrome. Significant decrease in insulin secretion was found in the early part of the glucose tolerance tests in the majority of the patients in both alcohol and withdrawal groups. Based on results of this study and evidence from the literature, it is suggested that chronic alcoholism is dabetogenic in susceptible individuals and that the transient carbohydrate intolerance found in our study represents and early step in the development of adult-onset diabetes eventually developing in a significant number of chronic alcoholics.