['To investigate the link between hepatitis C infection and glucose intolerance, we measured insulin sensitivity, glucose effectiveness and beta-cell secretion in noncirrhotic HCV-infected patients with normal glucose tolerance according to WHO criteria as assessed by oral glucose tolerance tests.', 'Glucose, insulin and C-peptide data from frequently sampled intravenous glucose tolerance tests were analyzed using the minimal modeling technique for glucose and C-peptide to determine insulin sensitivity, glucose effectiveness, first and second phase insulin secretion in noncirrhotic HCV-infected patients (n = 10) and in healthy control subjects (n = 10). Histological activity index (HAI) as well as the extent of fibrosis were evaluated by scoring liver biopsies.', 'Insulin sensitivity (2.72 +/- 1.63 vs. 6.84 +/- 1. 20 10(-4) min(-1) per microU/ml, p < 0.01) and glucose effectiveness (2.29 +/- 0.45 vs. 2.89 +/- 0.39 10(-2) min(-1), p < 0.05) ere significantly lower in patients with HCV-induced liver disease. Insulin sensitivity was negatively related to serum alanine aminotransferase (r = -0.47, p < 0.05) and aspartate aminotransferase concentrations (r = -0.65, p < 0.05). Multiple linear regression analysis revealed a strong relation of insulin sensitivity with fibrosis score and HAI (r = -0.82, p < 0.02 for both). Second phase insulin secretion was significantly enhanced in HCV-infected patients (14.30 +/- 2.04 vs. 8.29 +/- 1.65 min(-1), p < 0.05).'] Does severity of HCV-induced liver damage alter glucose homeostasis in noncirrhotic patients with chronic HCV infection?