Impaired response to high-dose interferon treatment in African-Americans with chronic hepatitis C.

Background/aims: The prevalence of hepatitis C virus infection in the USA is higher among African-Americans than among Caucasians. Despite this, little information is available on the course of hepatitis C virus infection in Blacks and in other minority groups. The aim of this retrospective case-control study was to determine the response rate to high dose interferon-alpha treatment in two racial groups with chronic hepatitis C virus infection.
Methodology: Thirty-one African-Americans and 62 Caucasians with chronic hepatitis C were considered in the study. The subjects were matched for gender, age, presence/absence of cirrhosis, histologic score, and viral genotype. All were treated with interferon-alpha (5 mU/day for 12 months). Three end-points (on-therapy, after 6 months of interferon-alpha, end-of-therapy, at the end of the 12 months of treatment, and off-therapy, 6 months after treatment) were chosen to describe the response to interferon-alpha treatment.
Results: African-Americans had a significantly reduced response to interferon-alpha as compared to Caucasians at all end-points. At the on-therapy end-point, 26% of African-Americans were HCV-RNA negative and had normal transaminases level as compared to 60% of the Caucasians (P < 0.01); at the end-of-therapy end-point the rates were, respectively, 10% and 53% (P < 0.0001). No differences were detected in terms of pretreatment serum ALT, HCV-RNA, iron and ferritin levels or hepatic iron contents between the two groups.
Conclusions: African-Americans have a reduced response to high-dose interferon-alpha treatment as compared to Caucasians. Both environmental and genetic factors may be implicated in this impaired ability to clear hepatitis C virus infection.