December 9, 2009
The incidence of new hepatitis C virus infections has declined in the United States, and improvements in antiviral therapy have been dramatic. Yet a significant barrier to treatment uptake is lack of diagnosis, according to a new study by Dr. Michael L. Volk, of the University of Michigan's Division of Gastroenterology and Hepatology, and colleagues. Previous studies have predicted a two- to four-fold increase in mortality over the next 20 years due to longstanding HCV infection.
The researchers obtained treatment data through an electronic audit of US pharmacies that filled patients' new prescriptions for pegylated interferon alpha-2a and -2b (Pegasys and Peg Intron, respectively) during 2002-2007.
In 2002, there were 126,000 new prescriptions for pegylated interferon products. That declined to 83,000 prescriptions by 2007. At that treatment rate, the researchers estimated that a cumulative total of less than 1.4 million people would be treated for HCV by 2030.
The study authors sought reasons for the decline in treatment, using data from the National Health and Nutrition Evaluation Survey Hepatitis C Follow-Up Questionnaire. Among respondents with HCV, 49 percent were previously unaware of their infection; 24 percent were not counseled to begin treatment by their physician; 9 percent did not follow up on physician advice; and only 12 percent received treatment. Given declining treatment rates, the authors estimated that just 14.5 percent of liver-related deaths due to HCV from 2002-2030 would be prevented by antiviral therapy.
Barriers to HCV screening and treatment may include lack of health insurance, limited access to care, and a lower priority for HCV screening among physicians, the study authors suggested.
"It is concerning that half of all people with hepatitis C in the US are unaware of their diagnosis," said Volk. "Even with the development of new and better medications on the horizon, such medications will have less than optimal impact unless more patients are diagnosed and referred for treatment."
The full report, "Public Health Impact of Antiviral Therapy for Hepatitis C in the United States," was published in Hepatology (2009;50(6):1750-1755).