Time on opioid agonist therapy predicts HCV treatment uptake in people who use drugs: a historical cohort based on French national healthcare database, 2012-2017 (the ANRS FANTASIO project)

Abstract Background Opioid Agonist Treatments (OAT), i.e., methadone and buprenorphine, are key elements in the treatment of opioid addiction. Moreover, they help foster healthcare behaviors and reduce medical harm in people who use opioid drugs (PWUD). Here, aimed to explore whether the percentage of time on OAT (pOAT) among PWUD with hepatitis C virus (HCV) was significantly associated with an increased uptake of direct antiviral agents (DAA). In France, 80% of PWUD have more or less regular deliveries of OAT, and OAT recipients are good proxy for PWUD. Methods Using the quasi-exhaustive French nationwide healthcare system database, we included all French individuals with chronic HCV receiving at least one OAT dispensing between 1 January 2012 and 31 December 2016. Subjects already treated by DAA at the time of first OAT delivery were excluded. The initiation of DAA during the study period was modeled using pOAT, which was computed as the number of days covered by OAT delivery, divided by the number of days of the study period of each participant. A Cox proportional hazards model allowed us to estimate the association between pOAT and DAA uptake (defined as the first delivery of treatment) during the study period, after adjustment for age, gender, alcohol use disorder, precarity indicator, and liver disease severity, respectively. Results Among the 22,615 persons included in the study, 3,438 (15.2%) had at least one dispensing of DAA during the study period. After multivariable adjustment, pOAT was associated with increased DAA uptake (adjusted hazard ratio [95% confidence interval]: 1.02 [1.01–1.04] per each 10% increase, p = 0.001). Other variables associated with DAA uptake were male sex, older age, cirrhosis or liver cancer, and higher socioeconomic status. Conclusions DAA uptake in PWUD with chronic HCV is associated with a greater pOAT uptake. Fostering compliance to OAT, and expanding the use of entry points for OAT as entry or referral points for DAA initiation should be integrated into the strategies for eliminating HCV and reducing harms related to this virus.