Early and Sustained Mediators of Depression Reduction Six Months Post-Treatment with Group Support Psychotherapy among People Living with HIV in Uganda: A Sequential Mediation Analysis

Background:

Group Support Psychotherapy (GSP) is an evidence-based, first-line treatment for mild to moderate depression among people living with HIV, though the psychosocial pathways underlying its sustained effects remain poorly understood.

Methods: We conducted a secondary analysis of a cluster-randomised trial in Uganda, comparing GSP to Group HIV Education among people living with HIV and mild to moderate depression. Using generalised structural equation modelling, we assessed whether changes in coping strategies and psychosocial factors mediated intervention effects on depression at 2 and 6 months. Single-mediator and sequential mediation models were used to evaluate early and sustained pathways, with indirect effects estimated using bias-corrected bootstrap confidence intervals. All analyses accounted for clustering at the therapy-group level.

Results:
In single mediator models, emotional support seeking was the only coping strategy that significantly mediated reductions in depression at both 2 and 6 months (β = -0.096, 95% CI [-0.185, -0.007] and β = 0.076, 95% CI [0.005, 0.147]). In sequential models, post-therapy mediation pathways were stronger than early pathways during therapy. Sustained mediation effects were significant for emotional support seeking (β = -0.158, 95% CI [-0.283, -0.033]), self-distraction (β = -0.171, 95% CI [-0.308, -0.0341]), active coping (β = -0.244, 95% CI [-0.413, -0.0751]), positive reframing (β = -0.249, 95% CI [-0.455, -0.043]), social support (β = -0.166, 95% CI [-0.284, -0.047]), and self-esteem (β = -0.188, 95% CI [-0.375, -0.001]). Chained mediation pathways between emotional support seeking and other mediators were non-significant.

Conclusion:
GSP appears to have distinct mechanisms of action during and after therapy. Emotional support seeking plays a central early role, operating independently rather than through other psychosocial factors, while sustained reductions in depression are reinforced by continued reduction in stigma, improvements in adaptive coping, social support, and self-esteem. Further research is needed to explore potential synergistic pathways.