Impact of hepatitis C serostatus on health service utilization for opioid-related harms among individuals prescribed opioid agonist therapy: a longitudinal prospective cohort study

Objectives — Varied substance use outcomes have been reported among individuals with a hepatitis C viral (HCV) infection on opioid agonist treatment (OAT) for opioid use disorder. Accordingly, the current study sought to evaluate the association between HCV serostatus, among other factors, and opioid-related acute health service utilization (e.g., emergency department [ED] visits and hospitalizations) among individuals prescribed OAT.

Methods — Multi-site prospective cohort study data were used to characterize demographic characteristics, substance use patterns, and physical health amongst individuals prescribed OAT. Logistic regression models were built to estimate the association between HCV-seropositivity and opioid-related ED visits and hospitalizations over a three-year follow up period.

Results — Among 3430 participants, 10.6 % (n = 365) were HCV-seropositive. In the follow-up period, 21.3 % (n = 730) attended the ED and 8.7 % (n = 298) were hospitalized for opioid related-harms. HCV-seropositivity was associated with an increased incidence of ED visits for opioid poisoning (9.0 % vs 4.9 % for participants who were HCV-seronegative, p < 0.01) and other opioid-related harms (22.5 % vs. 20.8 % for seronegative participants, p = 0.03). However, multiple logistical regression models showed no association between HCV serostatus and opioid-related health service utilization; rather, injection drug use was a significant predictor of opioid-related ED visits (OR 3.39, p < 0.01) and hospitalizations (OR 1.21, p = 0.01).

Conclusion — Among individuals prescribed OAT, those with seropositive HCV have increased incidence of ED visits and hospitalizations for opioid-related harms, an association which may be driven by injection use practices. These findings highlight the importance of screening for injection use practices and health symptoms, as well as the potential role for targeting resources (e.g., harm reduction supplies, education regarding transmission) within this vulnerable subgroup.