In utero HIV exposure and anthropometry trajectories from birth through 8 years of age: findings from a prospective birth cohort in South Africa

BackgroundChildren who are HIV-exposed but uninfected (CHEU) may have suboptimal growth, but few data are available beyond infancy to inform public health strategies. MethodsWe investigated anthropometry trajectories from 6 weeks to 8 years in a South African birth cohort, the Drakenstein Child Health study. Anthropometry was assessed at least annually by trained study staff and converted to weight-for-age (WAZ), height-for-age (HAZ), and body mass index (BMIZ) z-scores. Stunting (HAZ <-2SD from 12 months) and overweight (BMIZ score >2 SD from 6 months) were secondary outcomes. Multivariable linear mixed effects models were used to estimate associations between HIV exposure status and anthropometry trajectories and explore the impact of maternal HIV factors among CHEU. FindingsAmong 1,072 children (CHEU n= 236 (22%), children unexposed to HIV (CHU) n= 836 (78%)) mean birthweight was 3035 grams(g) (SD 592); CHEU 3012g (SD 598) vs CHU 3041g (SD 590) and 15.7% of infants were preterm (18.3% CHEU vs 15.0% CHU). Among women with HIV, 99% were on antiretroviral therapy (ART; 80% efavirenz-based ART), and 65% had an undetectable viral load in pregnancy. In multivariable analyses, CHEU had lower WAZ (marginal difference (MD) -0.16 (95% CI -0.32, -0.01) and HAZ (MD -0.26, 95% CI -0.41, - 0.11) scores, compared to CHU. Differences were largest before 3 years, but similar between CHEU and CHU thereafter. There was no association between HIV exposure and BMIZ scores (MD -0.02, 95% CI -0.17, 0.12), stunting (MD 0.05, 95% CI -0.04, 0.13) or overweight (MD 0.05, 95% CI -0.04, 0.13). Among CHEU, timing of maternal ART initiation, ART regimen, and viral load in pregnancy were not associated with anthropometry outcomes. InterpretationCompared to CHU, CHEU had lower weight and height from birth to 8 years, driven by early life differences. Among CHEU, maternal HIV factors did not drive anthropometry outcomes.