Primary Care Associated With Follow Up Viral Load Testing in Patients Cured of Hepatitis C Infection With Direct Acting Antivirals at a Multidisciplinary Addiction Treatment Program: Insights From a Real-World Setting

Objectives Treatment of hepatitis C virus infection (HCV) with direct acting antiviral therapy is encouraged regardless of substance use status. Patients with substance use disorder are at risk of HCV reinfection after cure. Follow up viral load testing (FUVL) with HCV RNA is recommended. We investigated factors associated with adoption of FUVL in real-world clinical settings. Methods Medical records of all patients with SUD who achieved HCV cure with direct acting antivirals at a multidisciplinary addiction treatment program between 2014 and 2019 were reviewed as part of a quality improvement initiative. Demographic and clinical characteristics including SUD treatment, urine toxicology results, and medical service use were collected. Factors associated with FUVL were analyzed and the rate of HCV reinfection was determined. Results Among 149 patients, 58.4% received FUVL. Receipt of FUVL was associated with engagement in ongoing primary medical care after cure (AOR 4.39, 95% CI [1.67, 11.49]). The HCV reinfection rate among those who received FUVL was 1.95 per 100 person-years of follow up (95% CI [0.64, 5.98]). There was no significant difference in the percentage of negative urine toxicology results before and after cure. Conclusions Over half of a cohort of patients with substance use disorder cured of HCV received FUVL. The relationship between FUVL and engagement in primary medical and substance use treatment highlights the importance of integrated systems in providing longitudinal care for patients cured of HCV. Standardized interventions that facilitate FUVL testing and management of infectious complications of SUD in addiction treatment settings are needed.