Association of Direct-Acting Antiviral Treatment With Mortality Among Medicare Beneficiaries With Hepatitis C
Authors: Yamini Kalidindi, Jeah Jung, Roger Feldman, Thomas Riley
Journal: JAMA Network Open (2020)

<h3>Importance</h3> Direct-acting antiviral (DAA) drugs are highly effective in curing hepatitis C virus (HCV) infection. Previous simulations showed extended life as a key health advantage of DAA drugs, but real-world evidence on the association between DAA treatment and reduced mortality is limited. <h3>Objectives</h3> To examine the association of DAA treatment with mortality among Medicare beneficiaries with hepatitis C. <h3>Design, Setting, and Participants</h3> This cohort study used Medicare claims data of beneficiaries who sought hepatitis C care for the first time between January 1, 2014, and December 31, 2016, after at least a 1-year washout period. Medicare Part D files were used in identifying DAA therapy initiation and completion. Death dates, demographic data, and indicators of health risks were obtained from the Master Beneficiary Summary Files. Beneficiaries with hepatitis C were considered as patients with DAA treatment if they initiated DAA therapy during the study period. Beneficiaries with hepatitis C who did not initiate DAA therapy during the study period were considered as patients without DAA treatment. Patients without DAA treatment were selected using 1-to-1 propensity score matching. Data were analyzed between September 1, 2019, and March 31, 2020. <h3>Exposures</h3> Completion of DAA treatment. <h3>Main Outcomes and Measures</h3> Time to death from the index date of seeking hepatitis C care after at least a 1-year washout period. Cox proportional hazards regression models with time-varying exposure were used to compare mortality rates between propensity score-matched cohorts of patients with DAA treatment and those without DAA treatment. Separate analyses were performed for patients with or without cirrhosis. Heterogeneity in the association between DAA treatment and mortality by sex and dual-eligibility status was examined. <h3>Results</h3> A propensity score–matched sample of 51 478 Medicare beneficiaries with a mean (SD) age of 59.4 (11.1) years and 30 473 men (59.2%) was assessed. Of this total, 8240 patients (16.0%) had cirrhosis (5224 men [63.4%]; mean [SD] age, 62.3 [9.7] years) and 43 238 patients (84.0%) had no cirrhosis (25 249 men [58.4%]; mean [SD] age, 58.8 [11.3] years). The adjusted hazard ratio (HR) of dying between patients with DAA treatment and those without DAA treatment in the cirrhosis group was 0.51 (95% CI, 0.46-0.57). The association of DAA treatment with mortality did not differ by sex (women vs men: HR, 0.46 [95% CI, 0.38-0.56] vs HR, 0.53 [95% CI, 0.47-0.60];<i>P</i> = .27) or dual-eligibility status (non–dual-eligible HR, 0.52 [95% CI, 0.43-0.63] vs dual-eligible HR, 0.50 [95% CI, 0.44-0.57];<i>P</i> = .80) in the cirrhosis group. The adjusted HR of dying between patients with DAA treatment and those without DAA treatment among patients without cirrhosis was 0.54 (95% CI, 0.50-0.58). The association of DAA treatment with mortality did not differ by sex (women vs men: HR, 0.53 [95% CI, 0.46-0.60] vs HR, 0.55 [95% CI, 0.50-0.60];<i>P</i> = .66) among patients without cirrhosis. However, the survival advantage associated with DAAs for non–dual-eligible beneficiaries was statistically significantly higher than for dual-eligible beneficiaries among patients without cirrhosis (HR, 0.47 [95% CI, 0.41-0.55] vs HR, 0.57 [95% CI, 0.52-0.62];<i>P</i> = .02). <h3>Conclusions and Relevance</h3> In this cohort study, DAA treatment appeared to be associated with a decrease in mortality among Medicare beneficiaries with or without cirrhosis. These findings suggest that increasing access to DAA drugs for all patients with HCV infection, regardless of disease progression, could improve population health.