Hepatitis C and African Americans
Advances in our understanding of hepatitis C (HCV) infection have led to important improvements in treatment. Curative treatment is now possible for more and more people with HCV. Research in HCV has also taught us that the virus does not behave the same in all groups of people. One of the groups that HCV occurs in more frequently and is more difficult to treat is the African American population.
Greater prevalence among African Americans
One of the first clues that HCV behaved differently in certain groups came from the National Health and Nutrition Examination Survey (NHANES). NHANES is an ongoing study that evaluates the health and nutritional status of people in the US. The NHANES III (1988-1994) found that overall, HCV affected 1.8% or 3.9 million people in the US population. However, it occurred two times more frequently among African Americans (affecting 3.2% of this group) compared with Caucasians (1.5%). In particular, African American males had the highest prevalence of HCV. Among African American males ages 40 to 49 years, 10% were positive for HCV antibodies.1
In addition to HCV prevalence rates being higher among African Americans, the virus appears to progress from acute to chronic infection in a higher proportion of African Americans compared with other groups. Those who are infected with HCV genotype 1 appear to have higher amounts of the virus (viral load) in their body, and there is less of a chance that the body will spontaneously clear the virus on its own after exposure.2
While HCV is more prevalent among African Americans, the disease tends to be less severe in this group, with progression to cirrhosis occurring more slowly. In one US study of people with HCV, 22% of African American had cirrhosis compared with 30% of Caucasians. African Americans are more likely to have HCV genotype 1 (88% compared to 67% for Caucasians). Liver enzymes elevations, which indicate damage to the liver, tend to be lower among African Americans, as does the amount of inflammation and fibrosis in the liver. It is thought that differences in immune response among African Americans may account for the decreased severity of HCV in this group.3
Although, cirrhosis develops more slowly in African Americans with HCV infection, this slower progression may increase the chances for development of hepatocellular carcinoma (HCC) (liver cancer). HCV is one of the leading causes of HCC and African American men have one of the highest rates of HCC in the US. The annual number of cases of HCC among African Americans is two to three times higher than in Caucasians.4
HCV treatment in African Americans
Results from clinical trials have shown that African Americans have lower treatment response rates (sustained virologic responses [SVR]) with interferon + ribavirin-based treatment compared to Caucasians. SVRs with interferon + ribavirin-based treatment for HCV genotype 1 range from 19% to 28% for African Americans compared to 39% to 52% for Caucasians. One factor that may partly explain this difference is that there are fewer African Americans than Caucasians who have the CC IL28B polymorphism, a genetic variation in the IL28B gene that predicts favorable response to HCV treatment that uses peginterferon.5
In recent studies, the addition of a protease inhibitor (telaprevir [Incivek] or boceprevir [Victrelis]) to peginterferon + ribavirin greatly increased the rate of SVR compared with peginterferon + ribavirin alone among African Americans with HCV genotype 1. Rates of SVR with Victrelis + peginterferon + ribavirin ranged from 42% to 53% among treatment-naive (people who had never received treatment) and 53% to 61% among those who had failed previous treatment. With Incivek + peg interferon + ribavirin rates of SVR were 62% among treatment-naive and 55% among those who had failed previous treatment.5
The addition of protease inhibitors to peginterferon + ribavirin further improved response rates among African Americans with HCV. The addition of newer direct-acting antiviral agents, including the protease inhibitor simeprevir (Olysio) and the polymerase inhibitor sofosbuvir (Sovaldi), as well as other agents soon to enter the market, offer African Americans with HCV new hope that HCV can be successfully cured in more individuals.5
Learn more about IDSA/AASLD treatment recommendations for people with HCV.