Psychosocial factors account for a proportion of the difference in cognitive performance between persons with and without HIV

Objective: To investigate whether psychosocial factors account for a proportion of the difference in cognitive performance between persons with and without HIV.

Design: Cross-sectional study of 273 participants (178 persons with HIV) from a low income area of Cape Town, South Africa.

Methods: Participants completed comprehensive cognitive testing (7 domains) and 12 psychosocial measures (5 current: income, occupation, assets, accommodation, depressive symptoms, 7 from childhood: assets, quality of education, exposure to childhood trauma and violence, primary caregiver occupation and highest level of education), as well as demographic measures standard in cognition studies (age, sex, years of education). We investigated the HIV association with global cognitive performance after adjustment for standard demographic variables, exploratory psychosocial variables, and balancing characteristics of those with and without HIV using propensity score modelling.

Results: Persons with HIV had significantly lower scores than persons without HIV in 8/12 psychosocial variables. Of these, 7/12 significantly predicted global T-score. In unadjusted regression, HIV status was associated with a reduction in global T-score of 3.72 units. Adjustment for standard variables, reduced the effect of HIV on global T score by 26.9% to 2.72, additional adjustment for psychosocial variables reduced by 40.3% to 2.22, and adjustment for propensity scores by 42.7% to 2.13.

Conclusions: Persons with HIV in this setting have lower psychosocial indices, both current and in childhood, which are associated with lower cognitive test performance as an adult. This is incompletely mitigated by adjustments for standard demographic variables which risks overestimation of cognitive impairment on a population level.