Racial Differences Seen In Steatosis In Patients With Hepatitis C
07 Jan 2007
Caucasian patients with chronic hepatitis C virus (HCV) are more likely to have hepatic steatosis, or fat in the liver, compared to African-American patients. However, steatosis is not associated with HCV treatment response. These findings are published in the January 2007 issue of Hepatology, the official journal of the American Association for the Study of Liver Diseases (AASLD). Published by John Wiley & Sons, Inc., the journal is available online via Wiley InterScience.
Hepatic steatosis is common among patients with HCV and often indicates more advanced disease. Researchers, led by Hari Conjeevaram, M.D., M.S. Division of Gastroenterology at the University of Michigan at Ann Arbor, sought to investigate racial differences in the prevalence and severity of hepatic steatosis in patients with HCV, genotype 1. Additionally, they investigated the relationship between steatosis and body characteristics and other measures of insulin resistance. "We also wanted to assess whether the presence and severity of hepatic steatosis and/or insulin resistance were important factors to predict virological response in this population," the authors write.
The researchers studied 194 African-American and 205 Caucasian patients with HCV, genotype 1. All patients were participating in a multi-center prospective study of peginterferon and ribavirin therapy. The researchers compared the prevalence and severity of steatosis and steatohepatitis to demographic, lifestyle and clinical characteristics. They also investigated relationships between sustained virological response and both steatosis and insulin resistance.
The researchers found hepatic steatosis in 61 percent of the African-American patients and 65 percent of Caucasian patients. In a univariable analysis, the steatosis was associated with HOMA-IR (a measure of insulin resistance), body mass index, waist circumference, serum triglycerides, aminotransferase levels, and histological scores for inflammation and fibrosis. After adjusting for those features, they found that African-Americans had a dramatically lower risk of steatosis. For a given degree of overweight and obesity or insulin resistance, African-Americans were approximately half as likely to have hepatic steatosis. After examining patient characteristics and their responsiveness to treatment, the authors report, "insulin resistance and fibrosis are important and obesity and steatosis may be less or not as important."
The results may have been confounded by patients taking oral anti-diabetic agents, and by the possibility that HOMA underestimated the degree of insulin resistance in overtly diabetic patients.
Still, "the importance of these findings is that insulin resistance is a potentially modifiable factor, so that responses to antiviral therapy in hepatitis C may be improved by modulation of insulin signaling and improvements in insulin resistance and glucose control. These possibilities deserve prospective evaluation," they conclude.
This work was funded by grants from the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health.
Article: "Race, Insulin Resistance and Hepatic Steatosis in Chronic Hepatitis C," Hari S. Conjeevaram, David E. Kleiner, Jay E. Everhart, Jay H. Hoofnagle, Steven Zacks, Nezam H. Afdhal, and Abdus S. Wahed for the Virahep-C Study Group, Hepatology; January 2007 (DOI: 10.1002/hep.21455).