Diabetes is the main factor accounting for the high ferritin levels detected in chronic hepatitis C virus infection.

OBJECTIVE: A high prevalence of diabetes has been reported in patients with hepatitis C virus (HCV) infection. Both diabetes and HCV infection are associated with high serum ferritin levels. Although HCV infection could be the main factor responsible for the high ferritin levels, it is also possible that diabetes rather than HCV infection might be a major contributor to the high ferritin levels observed in patients with HCV infection. The aim of this study was to investigate the contribution of diabetes to the high ferritin levels observed in HCV-infected patients with chronic hepatitis. RESEARCH DESIGN AND METHODS: A total of 634 noncirrhotic individuals were prospectively recruited at a university hospital. According to the HCV antibody status and the presence of diabetes, the subjects were divided into four groups: group A (anti-HCV-positive diabetic patients, n = 53), group B (anti-HCV-negative diabetic patients, n = 242), group C (anti-HCV-positive nondiabetic patients, n = 191), and group D (anti-HCV-negative nondiabetic control subjects, n = 148). Multiple regression analyses were used to explore the variables independently related to ferritin levels.
RESULTS: Serum ferritin levels in group A were significantly higher than in the other groups (A > B, P < 0.01; A > C, P < 0.001; A > D, P < 0.001). Ferritin levels were higher in group B than in group D (P = 0.001). However, group C has ferritin values similar to those of group D. In multivariate analyses, diabetes but not HCV infection was independently related to serum ferritin concentrations.
CONCLUSIONS: Diabetes rather than HCV infection itself is the main factor associated with the increased ferritin levels detected in patients with HCV infection. Therefore, the presence of diabetes should be taken into account when iron metabolism is evaluated in HCV-infected patients.