Epidemiologists have determined that levels of hepatitis C virus (HCV) found among injection drug users (IDUs) were higher in individuals who are male or African American even after differences in other factors were considered. The study, which was funded by the National Cancer Institute and performed with collaborators from the National Institutes of Health Clinical Center and the University of California - San Francisco, was the first to simultaneously examine the association of demographic, viral and human genetic factors on HCV RNA levels. Results of the study published in the July issue of Hepatology, a journal of the American Association for the Study of Liver Diseases (AASLD), also showed higher levels of HCV among IDUs who were co-infected with human immunodeficiency virus (HIV).
A 2010 report from the Centers for Disease Control and Prevention (CDC) estimates that up to 3.9 million Americans have chronic HCV—a leading cause of liver cancer, end-stage liver disease and liver transplantation. According to the CDC 17,000 new cases and 2,800 acute cases of HCV were reported in 2010. Previous epidemiologic studies suggest one-third of those 18 to 30 year-old IDUs and up to 90% of older IDUs are infected with HCV.
"With such a high incidence and prevalence of hepatitis C virus infection among IDUs, it is important to understand the characteristics of the infection in this group," explains lead author Dr. Thomas O'Brien of the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Rockville, MD. "The HCV RNA level is an important predictor of response to treatment in patients with chronic hepatitis C. Our study is the first to examine simultaneously the viral, demographic, and genetic factors that impact HCV levels in ethnically diverse IDUs."
Participants were originally recruited for the Urban Health Study—a multi-ethnic group of IDUs in San Francisco. Researchers used interview data and biological samples from participants to analyze demographic, viral and host characteristics of cancer-causing viruses. A total of 1701 participants had detectable HCV RNA and were included in the present study. The median age at enrollment was 46 years and median age of first illicit drug injection was 18 years. Close to 75% of participants were men and 56% were African American, 34% European (non-Hispanic) and 7% Latino (non-African American).
Adjusted analysis revealed that age, gender, racial ancestry, HIV-1 infection, and IL28B rs12979860 genotype were all independently associated with the HCV RNA level. "We know that the level of HCV is an important predictor of treatment response and that these levels seem to be influenced by a number of demographic, clinical, viral and human genetic factors," concludes Dr. O'Brien.
Full citation: "HCV RNA Levels in a Multi-Ethnic Cohort of Injection Drug Users:Human Genetic, Viral and Demographic Associations." Lorenzo Uccellini, Fan-Chen Tseng, Alessandro Monaco, Fatma M. Shebl, Ruth Pfeiffer, Myhanh Dotrang, Dianna Buckett, Michael P. Busch, Ena Wang, Brian R. Edlin, Francesco Marincola, Thomas R. O'Brien. Hepatology; (DOI: 10.1002/hep.25652); Print Issue Date: July, 2012. URL: http://onlinelibrary.wiley.com/doi/10.1002/hep.25652/abstract
About the Author: Dr. Thomas O'Brien is with the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Rockville, Maryland.
To arrange an interview with Dr. O'Brien please contact the NCI Office of Media Relations at ncipressofficers@mail.nih.gov or at 301-496-4441.
This study is published in Hepatology. Media wishing to receive a PDF of this article may contact sciencenewsroom@wiley.com.
About the Journal: Hepatology is the premier publication in the field of liver disease, publishing original, peer-reviewed articles concerning all aspects of liver structure, function and disease. Each month, the distinguished Editorial Board monitors and selects only the best articles on subjects such as immunology, chronic hepatitis, viral hepatitis, cirrhosis, genetic and metabolic liver diseases and their complications, liver cancer, and drug metabolism. Hepatology is published on is published by Wiley on behalf of the American Association for the Study of Liver Diseases (AASLD). For more information, please visit http://wileyonlinelibrary.com/journal/hep.
About Wiley
Founded in 1807, John Wiley & Sons, Inc. has been a valued source of information and understanding for more than 200 years, helping people around the world meet their needs and fulfill their aspirations. Wiley and its acquired companies have published the works of more than 450 Nobel laureates in all categories: Literature, Economics, Physiology or Medicine, Physics, Chemistry, and Peace.
Our core businesses publish scientific, technical, medical, and scholarly journals, encyclopedias, books, and online products and services; professional/trade books, subscription products, training materials, and online applications and Web sites; and educational materials for undergraduate and graduate students and lifelong learners. Wiley's global headquarters are located in Hoboken, New Jersey, with operations in the U.S., Europe, Asia, Canada, and Australia. The Company's Web site can be accessed at http://www.wiley.com. The Company is listed on the New York Stock Exchange under the symbols JWa and JWb.
Journal
Hepatology