Hepatitis C treatment completion rates in routine clinical care.

BACKGROUND: Treatment completion rates for hepatitis C virus (HCV) infection in clinical practice settings are unknown.
METHODS: We assembled a national cohort of HCV-infected veterans-in-care from 1998 to 2003, using the VA National Patient Care Database for demographical/clinical information, Pharmacy Benefits Management database for pharmacy records and the Decision Support Systems database for laboratory data. We used logistic regression to determine the factors predicting treatment non-completion for HCV.
RESULTS: We identified 134,934 HCV-infected veterans of whom 16,043 [11.9%; 95% confidence interval (CI) 11.7-12.1] were prescribed treatment for HCV. Among the 10,641 veterans with >1 year of follow-up, 2396 (22.5%; 95% CI 21.7-23.3) completed a 48-week course. Non-completers were more likely to have pre-treatment anaemia, coronary artery disease, depression, substance abuse, used standard interferon, higher comorbidity count, and been treated at a low-volume treatment site (defined as sites initiating HCV treatment for <200 individuals). In multivariable analyses, treatment completion was positively associated with pegylated interferon use [odds ratio (OR) 1.59, 95% CI 1.40-1.80] and site treatment volume (OR 1.87, 95% CI 1.56-2.24 for sites initiating treatment for >200 individuals) and negatively associated with pre-treatment anaemia (OR 0.68, 95% CI 0.58-0.80 for haemoglobin 10-14 g/dl) and depression (OR 0.78, 95% CI 0.69-0.89). Human immunodeficiency virus coinfection and minority race were not associated with failing to complete treatment.
CONCLUSIONS: Among veterans-in-care with known HCV, 11.9% initiate therapy of whom 22.5% (one in 56 with known HCV infection) complete a 48-week course of treatment. Higher completion rates among higher volume treatment sites suggest that some factors associated with non-completion (pre-treatment depression and anaemia), may be modifiable with experience.