Immune Activation Is Associated With Neurocognitive Performance in Ugandan Adolescents Living With HIV

Abstract

We examined relationships between neurocognition and immune activation in Ugandan adolescents with perinatally acquired HIV (PHIV). Eighty-nine adolescents in Kampala, Uganda (32 virally suppressed [<400 copies/mL] PHIV and 57 sociodemographically matched HIV-negative controls), completed a tablet-based neurocognitive test battery. Control-derived z-scores for 12 individual tests and a global/overall z-score were calculated. We measured plasma (soluble CD14 and CD163), monocyte (proportions of monocyte subsets), and T-cell (expression of CD38 and HLA-DR on CD4 + and CD8 + ) activation and gut markers. Spearman rank correlations and median regressions examined associations between test performance and immune activation. The median [IQR] age was 15 [13-16] years, and 40% were girls. The median time on antiretroviral therapy was 10 years [7-11] for PHIV; 87% had viral load <50 copies/mL. Compared with controls, global z-scores were lower among PHIV ( P = 0.05) and significantly worse on tests of executive functioning and delayed recall ( P 's ≤ 0.05). Overall, monocyte activation significantly correlated with worse test performance on global z-score (r = 0.21, P = 0.04), attention, processing speed, and motor speed (r = 0.2-0.3, P ≤ 0.01). T-cell activation was significantly correlated with worse performance on tests of learning, executive functioning, and working memory (r = 0.2-0.4, P ≤ 0.04). In PHIV, after adjusting for age, sex, and antiretroviral therapy duration, activated CD4 T cells remained associated with worse memory (β-0.3, 95% CI: -0.55 to -0.07, P = 0.01). PHIV with virologic suppression on antiretroviral therapy shows evidence of worse neurocognitive test performance compared with controls. Monocyte and T-cell activation is correlated with worse neurocognition in Ugandan youth with and without HIV, which has not been previously investigated in this setting.