Chronic liver disease: Do alcohol and hepatitis C virus interact?

In chronic liver disease, alcoholism and hepatitis C virus (HCV) frequently coexist, and it is widely believed that they interact to result in more severe disease. However, the issue is far more complex and that view may be incorrect. Newer HCV assays cast doubt on the earlier results. Data acquired in one country are often at variance with those from other countries, suggesting that other factors may be involved in the variability of the disease. Further comparison of histologically different groups of individuals with excess alcohol intake is unlikely to shed further light on the issue unless information on the duration and quantity of alcohol consumption and the duration of HCV infection is available. The net evidence is that HCV and alcohol produce different histological appearances in the precirrhosis stage, with the end result cirrhosis often being indistinguishable, regardless of aetiology. Nevertheless, even with both aetiologies, progression is slow and only a minority of people develop cirrhosis despite the combination of HCV and heavy alcoholism. As yet there is no definite evidence that cirrhosis develops more frequently or sooner if both HCV and alcohol are present. Although the majority of the evidence suggests that these insults are probably additive, there is a possibility that alcohol and HCV do interact in the pathogenesis of chronic liver disease. Further studies will be necessary, however, to clarify their relationship.