High prevalence of diabetes mellitus in patients with chronic hepatitis C. A case-control study

Objectives and methods. - Extrahepatic manifestations have been reported in hepatitis C virus infection. To assess the relationship between diabetes mellitus and hepatitis C virus, we studied 152 patients with chronic hepatitis C and 152 controls hospitalized during the same period with hepatitis B virus (n = 51) or alcohol-induced (n = 101) liver diseases matched for age, sex, and the presence of cirrhosis (prevalence: 58 %). Patients with jaundice, ascites, encephalopathy, prothrombin activity < 65 %, or serum albumin < 35 g/L were excluded. Results. - Diabetes, defined by fasting serum glycemia > 1.4 g/L on at least two separate occasions or previously treated overt diabetes, was present in 38 patients with chronic hepatitis C (24 %) and in 13 patients in the control group (9 %, P < 0.002). In the 51 diabetic patients, irrespective of serum anti-hepatitis C virus status, 41 (81 %) had non insulin dependent diabetes and 45 (88 %) had cirrhosis. Family history of diabetes or obesity was observed in 2 (5 %) of the diabetic patients with chronic hepatitis C and in 6 (46%) of the diabetic controls (P = 0.002). Plasma C-peptide (855 +/- 448 pmol/L versus 1 152 +/- 491 pmol/L, NS) and insulin levels (83 +/- 40 pmol/L versus 184 +/- 86 pmol/L, NS), assayed in 17 diabetic patients with chronic hepatitis C and in 9 diabetic controls, were lower in the former. The prevalence of HLA B8, DR3 or DR4 antigens, which was searched for in 77 patients with chronic hepatitis C, was not different in diabetic and non diabetic patients, and, was similar to the reference population. Serum islet-cell antibodies were found in 5 patients with chronic hepatitis C (3 with diabetes) and in 2 controls. Conclusion. - Diabetes mellitus is more prevalent in patients with chronic hepatitis C than in patients with other liver diseases, and usually occurs in the absence of predisposing factors. These results suggest a role of hepatitis C virus infection in the pathogenesis of diabetes.