The impact of financial incentives on mental health among adults in HIV care in Lake Zone, Tanzania.

Objective: Depression and anxiety are prevalent among people with HIV (PWH), hindering retention in care. Though economic interventions can improve care engagement and mental health in the general population, this remains understudied among PWH. This study assessed whether financial incentives improve mental health among adult antiretroviral therapy (ART) initiates in Lake Zone, Tanzania.

Design: Two-arm randomized controlled trial.

Methods: From 2021 to 2023, 32 clinics were randomized to offer patients monthly financial incentives (22 500 TSH/US$ 10) for ≤six months (conditional on visit attendance) or standard-of-care (SoC) services. We assessed changes in depression (PHQ-2 scores) and anxiety (GAD-2 scores) symptoms at baseline, six, and 12 months. Difference-in-differences effects were used to estimate changes over time by arm using inverse probability of censoring sample weights (IPCW).

Results: Participants ( n  = 1990) were 57.3% female; median age was 35.0. Baseline prevalences of depression and anxiety symptoms were 66.2% and 60.4%, respectively, and endline prevalences were 7.8% and 7.6% in the intervention and SoC arms, respectively, with no differences by arm. Using IPCW, the differences in the prevalence of depression and anxiety symptoms in the intervention arm compared to the SoC arm were 2.5 percentage points [95% confidence interval (CI): -3.0, 8.0) and 2.3 percentage points (95% CI: -3.2, 7.9) respectively after six months, and 5.5 percentage points (95% CI: -0.20, 10.8) and 3.8 percentage points (95% CI: -1.5, 9.2) respectively after 12 months.

Conclusion: Both study arms experienced substantial reductions in poor mental health, primarily within the first six months of care. Financial incentives provided in this study did not significantly augment these downward trends but may improve engagement in care, indirectly improving mental health.