1Institute for Research, Quality, and Policy in Homeless Health Care, Boston Health Care for the Homeless Program, Boston, MA, USA.
2The Kirby Institute, UNSW Sydney, Sydney, NSW, Australia.
Background: People experiencing homelessness are disproportionately affected by hepatitis C virus (HCV) infection compared to housed populations. Surveillance for HCV reinfection after successful treatment is a critical step in the care cascade, but limited data on reinfection are available among this highly marginalized group. This study assessed post-treatment reinfection risk in a real-world cohort of homeless-experienced individuals in Boston.
Methods: Individuals receiving HCV direct-acting antiviral treatment through Boston Health Care for the Homeless Program during 2014-20 with post-treatment follow-up assessment were included. Reinfection was identified based on recurrent HCV RNA at 12 weeks post-treatment with HCV genotype switch or any recurrent HCV RNA following sustain virologic response.
Results: A total of 535 individuals were included (81% male, median age 49 years, 70% unstably housed or homeless at treatment initiation). Seventy-four HCV reinfections were detected, including five second reinfections. HCV reinfection rate was 12.0/100 person-years (95%CI 9.5-15.1) overall, 18.9/100 person-years (95%CI 13.3-26.7) among individuals with unstable housing and 14.6/100 person-years (95%CI 10.0-21.3) among those experiencing homelessness. In adjusted analysis, experiencing homelessness (vs. stable housing, adjusted HR 2.14, 95% CI 1.09-4.20, p=0.026) and drug use within six months prior to treatment (adjusted HR 5.23, 95%CI 2.25-12.13, p<0.001) were associated with increased reinfection risk.
Conclusion: We found high HCV reinfection rates in a homeless-experienced population, with increased risk among those homeless at treatment. Tailored strategies to address the individual and systems factors impacting marginalized populations are required to prevent HCV reinfection and to enhance engagement in post-treatment HCV care.