Background: Low adherence can undermine the efficacy of daily oral pre-exposure prophylaxis (PrEP). Mental health conditions, particularly depression, could be associated with low PrEP adherence, especially for women.
Setting: We analyzed data from 1013 Kenyan and Ugandan HIV-uninfected participants in the Partners Demonstration Project, an open-label study of PrEP delivered to HIV-uninfected members of serodiscordant couples.
Methods: Participants completed quarterly visits over 2 years and were encouraged to use PrEP until their partners living with HIV had ≥6 months of antiretroviral therapy use (when viral suppression was expected). PrEP adherence was measured daily with electronic medication event monitoring system caps and dichotomized into low (<80% of expected bottle openings) and high adherence. Depression was assessed annually using the 16-item Hopkins Symptom Checklist screening tool; scores >1.75 indicate "probable depression." The association between probable depression and PrEP adherence was assessed separately for men and women using generalized estimating equations and marginal structural models.
Results: At enrollment, 39 (11.7% of 334) women and 64 (9.4% of 679) men reported symptoms indicating probable depression, and these proportions decreased during follow-up (P < 0.001 for women and men). Probable depression was significantly associated with low PrEP adherence among women (adjusted risk ratio = 1.77; 95% confidence interval: 1.14 to 2.77; P = 0.01); there was no association between depression and adherence among men (P = 0.50). Marginal structural models and sensitivity analyses confirmed these findings.
Conclusions: Depression was relatively uncommon in this population and was an independent risk factor for low PrEP adherence among women. For PrEP programs targeting African women, integration of depression screening may improve PrEP effectiveness.