Cofactors of Longitudinal Linear Growth Among Infants with and Without In-utero HIV/Antiretroviral Exposure in Kenya

Effective treatments have decreased vertical transmission of HIV and most infants born to women living with HIV (WLH) are HIV-exposed but uninfected (HEU). There is evidence that HEU infants have poorer growth than HIV-unexposed uninfected children (HUU). The biological and social mechanisms for growth deficits in HEU are unclear. There are few large studies comparing HEU and HUU in the era of dolutegravir antiretroviral treatment (ART). WLH may be at higher risk for concurrent illnesses, mental health challenges, food insecurity, and low social support, all of which may influence infant growth and development. We leveraged data from maternal-infant dyads living in Western Kenya (n =1000 HEU, n=1000 HUU) to determine biological and social factors affecting longitudinal infant growth (length and weight-for-age z-scores [LAZ, WAZ] and weight for length z-scores[WLZ]) and stunting (LAZ<-2, underweight (WAZ<-2), and wasting (WLZ<-2) ) from birth to 1 year. We found a higher prevalence of stunting, underweight, and wasting and lower length and weight for HEU compared to HUU infants. HEU infants had lower LAZ at 6 and 12 months, but not WAZ or WLZ. In the combined cohort of HEU and HUU, maternal age, lower education, intimate partner violence (IPV), maternal and infant morbidity, and food insecurity were associated with growth deficits, with some of these factors detected in stratified HEU or HUU subcohorts. High levels of social support were protective for LAZ. Among HEU, ART regimen and timing (pre- vs. post-pregnancy) did not affect growth trajectories. Addressing comorbidities, education, food insecurity, and IPV and amplifying social support may improve growth outcomes overall and among HEU.