Carbohydrate metabolism in alcohol-induced fatty liver. Evidence for an abnormal insulin response to glucagon in alcoholic liver disease.

An intravenous glucose tolerance test and an intravenous glucagon test were performed in 21 alcoholics with fatty liver. The effect on insulin secretion and blood glucose concentrations was compared with the effect in 21 normal subjects and 21 patients, of the same age and weight, with alcoholic cirrhosis. The average glucose tolerance in patients with fatty liver was lower than normal. Forty-eight per cent had a diabetic glucose tolerance. The glucose tolerance in cirrhosis was significantly lower, and it was impaired in 86% of the patients with alcoholic cirrhosis. In both cirrhosis and fatty liver the concentrations of insulin were above normal before and during the two tests. The insulin-glucose ratio was increased in the liver patients during glucagon stimulation, and there was no significant difference between the two types of liver disease. During glucose stimulation the insulin-glucose ratios were equal in liver patients and normal subjects. It is concluded that the carbohydrate metabolism in alcoholic fatty liver is impaired as in alcoholic cirrhosis, although to a lesser degree. The abnormal response to glucagon is suggested to be due to an increased β-cell sensitivity in fasting chronic alcoholics.