The effect of environment and in-utero HIV exposure on neurodevelopment in infants

Objective: Estimate the independent contributions of in utero HIV exposure and postnatal environment on neurodevelopment at 24 months of age. 

Methods: We recruited mother – infant pairs from 2018 to 2022 during the second trimester of pregnancy in Malawi. Children who were HIV-exposed and uninfected (CHEU) and children unexposed to HIV and uninfected (CHUU) were followed to 24 months of age for neurodevelopmental outcomes. Environmental data was collected at 18 or 24 months. Neurodevelopment was measured using Malawi Developmental Assessment Tool, Communication Development Inventory, and Behavioural Rating Inventory of Executive Functions. Postnatal factors included maternal mental health, home learning environment, observed mother – child interactions, and socioeconomic status (SES). Exploratory factor analysis and structural equation modeling were used to simultaneously estimate the impact of exposures on latent developmental outcomes. 

Results: There were 643 children with 24-month outcome data, 49% of which were CHEU. Three latent factors were identified for neurodevelopment: Language, Executive Function, and Child Development. The factors did not correlate closely with each other and had different biological and environmental drivers. Quality of mother – child interactions was the strongest predictor of Child Development (P < 0.001) and maternal mental health was a strong predictor of Executive Function (P < 0.001). Despite adjustment for all environmental variables, CHEUs had lower Child Development scores than CHUU (P ¼ 0.01). 

Conclusion: Developmental scores of CHEU were lower than those of CHUU despite high maternal ART use, after accounting for postnatal environment. Despite this, the impact of high-quality maternal – child interactions on child development outweighed the impact of HIV exposure on neurodevelopment in this population.