The currently recommended treatment for hepatitis C virus (HCV) infection is pegylated interferon alfa (PEG-INF) and ribavirin, which can be difficult to tolerate. More information about predicting sustained virologic response (SVR) may allow more informed treatment decisions to be made. This retrospective observational cohort study identified predictors of SVR to PEG-INF and ribavirin in routine medical practice at 121 Department of Veterans Affairs facilities. Among 5,944 patients infected with HCV genotypes 1, 2, or 3 who had been treated with PEG-INF and ribavirin, SVR rates were 20%, 52%, and 43%, respectively, and discontinuation rates were 68% (prior to 48 weeks), 34% (24 weeks), and 41% (24 weeks), respectively. In multivariate analysis, significant predictors of decreased likelihood of genotype 1 patients having an SVR were being African American, clinical liver disease, diabetes, low cholesterol, low hemoglobin, low platelet count, and treatment at a low-volume facility. Predictors of increased likelihood of genotype 1 patients having an SVR were low-level HCV viremia, elevated ALT quotient, and receiving PEG-INF 2A (rather than 2B). For genotype 2 patients, increasing body mass index, prior use of interferon, and low platelet count were negative predictors; only low-level HCV viremia was a positive predictor. For genotype 3 patients, only receiving PEG-INF 2A affected the likelihood of an SVR; its effect was positive. Conclusion: Among patients for whom HCV treatment is initiated during routine medical care, multiple factors including form of PEG-INF received affect the SVR rate for genotype 1 patients. Few of these factors affect the rate for genotype 2 patients, and even fewer do so for genotype 3 patients. (HEPATOLOGY 2007;46:37-47.) I n the United States, the recent National Health and Nutrition Examination Survey estimated that approximately 3.2 million people have chronic hepatitis C virus (HCV) infection. In the United States, HCV infection accounts for approximately 40% of all those with chronic liver disease, is the most frequent indication for liver transplantation, and causes 8,000-10,000 deaths annually. 2 Moreover, morbidity and mortality from HCV infection are expected to increase dramatically. Based on 3 pivotal clinical trials, 4-6 the current standard of care for HCV treatment is a combination of pe-gylated interferon alfa (PEG-INF) and ribavirin. 7 Although this treatment promises to reduce HCV morbidity and mortality, 8 it can be difficult to tolerate. About 60% of patients develop fatigue and flu-like symptoms, 20%-30% experience depression, 10%-20% develop neutropenia, and 10%-20% develop anemia. [10] The rate of discontinuing treatment in clinical trials because of side effects has ranged from 14% to 21% 4-6 and is likely higher in routine medical practice. Given the likelihood of side effects and the possibility of discontinuation, additional information about predicting sustained virologic response (SVR) may allow clinicians and patients to make more informed treatment decisions.
The Department of Veterans Affairs (VA) provides comprehensive medical care to a large HCV-infected population, which makes it possible to assess SVR rates and predictors in routine medical practice.
Materials and Methods
We used the VA Clinical Case Registry: Hepatitis C (CCR:HepC), an extract of VA electronic medical record information for HCV-infected patients receiving care at any VA medical facility. The CCR:HepC contains data