Differential risk for Hepatitis C and HIV among people who inject drugs in Kenya: a latent class analysis signaling needs for innovation in service delivery.

BACKGROUND

Subgroups of people who inject drugs (PWID) may experience differential exposure to HIV and hepatitis C (HCV). This study analyzes behavioral risk profiles associated with HIV and HCV infection among PWID, with the aim of identifying subgroups at highest risk and guiding future interventions.

METHODS

We recruited PWID in Kenya using respondent driven sampling. Participants completed behavioral surveys and point-of-care HCV, HIV, and hepatitis B (HBV) testing. We used latent class (LC) analysis to divide the sample into mutually exclusive classes based on nine risk- and service access-related measures.

RESULTS

Among the 3152 participants enrolled, one-fifth (N = 610, 19.4 %) were HCV antibody-positive, one-tenth were HIV-positive (N = 306, 9.7 %), and 1.3 % (N = 40) were HBV-positive. We obtained three LCs: LC1 - long-term, high-frequency PWID with large networks, high access to NSP services, and moderate access to OAT (N = 1522, 48.3 %), LC2 - newer, high-frequency PWID with large networks, moderate access to NSP services, and moderate access to OAT (N = 878, 27.8 %), and LC3 - long-term, low-frequency PWID with small networks, high access to NSP, and moderate access to OAT (N = 752, 23.9 %). HIV and HCV prevalence and risk behaviors differed between the classes, and classes differed in demographic characteristics as well.

CONCLUSION

Subgroups of PWID in Kenya have different risk for HIV and HCV, influenced by duration of injection, network size, service access, and other behavioral risk factors. Targeted interventions to meet each subgroup's needs are essential to prevent ongoing HCV and HIV epidemics among PWID.