Effects of alcohol and liver cirrhosis on the GH-IGF-I axis.

Decreased serum insulin-like growth factor (IGF-I) levels have been shown in malnutrition and liver diseases. To analyse which of them is the main cause of GH-IGF-I axis alterations, serum levels of growth hormone (GH), growth-hormone releasing factor (GHRH), IGF-I and its binding protein IGFBP-3 were measured in 85 hospitalized alcoholics (51 without cirrhosis, 15 with compensated cirrhosis and 19 with cirrhosis with ascites) and in 25 healthy controls. Liver function tests and objective nutritional assessment were also performed. Serum IGF-I and IGFBP-3 levels were lower in alcoholics, particularly in those with liver cirrhosis. Serum GH was raised in cirrhotics with ascites but GHRH levels were not significantly altered. Although these patients were frequently malnourished there was no relationship between data derived from GH-IGF-I axis and nutritional parameters. However, there was a significant positive correlation between serum GH concentrations and impaired liver function and a significant negative correlation between serum IGF-I and IGFBP-3 and impaired liver function. This suggests that, in this population, serum IGF-I and IGFBP-3 levels reflect liver dysfunction rather than malnutrition.