Population-level hepatitis C reinfection rates after direct-acting antiviral therapy were elevated among people who inject drugs due to ongoing exposure risk, according to a recently published study.
“As expected, recent PWIDs had the highest reinfection rates,” Carmine Rossi, MD, from the British Columbia Center for Disease Control in Vancouver, British Columbia, and colleagues wrote. “Our results highlight the need for engagement of people with ongoing injecting risk in harm-reduction and support services to prevent reinfections following successful treatment.”
Rossi and colleagues identified 5,292 individuals in British Columbia who had been treated with all-oral DAA therapy and achieved sustained virologic response between Jan. 23, 2014, and July 15, 2017.
The study comprised 4,114 of those identified who had at least one post-SVR HCV RNA measurement, 65% of whom had a history of recent (21%) or former (44%) injection drug use. Among the PWIDs, 19% had previous opioid-agonist therapy.
During follow-up, the researchers identified 40 reinfections including 21 among the PWIDs. Reinfection rates were more common among individuals aged younger than 45 years, those born after 1975, men, recent PWIDs, and those with major mental illness, problematic alcohol consumption and HIV coinfection.
Further analysis confirmed that reinfection rates were highest among recent PWIDs born after 1975 (10.2 per 100 person-years; 95% CI, 3.74-22.2), those with HIV coinfection (5.67 per 100 person-years; 95% CI, 2.59-10.8) and those with problematic alcohol use (4.55 per 100 person-years; 95% CI, 2.35-7.94).
Among recent PWIDs, the cumulative risk for both overall and persistent reinfection increased rapidly during the first 36 weeks after SVR and became less common afterward.
Multivariate analysis showed that PWIDs with recent (IRR = 6.7; 95% CI, 1.9-23.5) and former injection drug use (IRR = 3.7; 95% CI, 1.1-12.9) had a significantly higher risk for reinfection.
“As with primary HCV infection, a myriad of single and multicomponent prevention strategies have been suggested to reduce ongoing exposure,” Rossi and colleagues wrote. “These include provision of [opioid-agonist therapy] and high-coverage needle-syringe programs (NSP), as well as psychotherapy and peer-based drug cessation programs for stimulant use. With the ongoing opioid-related epidemic in North America, integrated services are expected to improve overall health and survival of PWIDs.” – by Talitha Bennett
Disclosure: Rossi reports no relevant financial disclosures. Please see the full study for the other authors’ relevant financial disclosures.