Health outcomes in a cohort of children born to HIV-infected mothers in Zambia

Of the 27 million adult HIV cases in sub-Saharan Africa more than 50% are women of childbearing age. Worldwide, 2 million children are infected and many more are uninfected but experience the adverse health effects of their mother's disease. Using prospective data from a Zambian breastfeeding intervention trial we examined the impacts of different exposures on health outcomes in children born to HIV-infected women.; In study one, we included 187 HIV-infected children to compare mortality rates among children infected postpartum to those infected during gestation or delivery. After adjusting for birth weight, maternal CD4 count, breastfeeding cessation and maternal death, the hazard ratio comparing child mortality between those infected after 40 days with infection before 3 days was 0.25 (95% CI 0.13-0.47). No differences in mortality were detected between those infected 4-40 days and those infected after.; In study two, we examined whether maternal CD4 count predicted infant weight-for-age Z-scores (WAZ) among 753 HIV-uninfected children. At birth, WAZ was significantly reduced in the <200 maternal CD4 count group vs. >500 (mean difference - 0.34; 95% CI -0.52 to -0.15). Nearly one third of a standard deviation difference persisted through nine months. After adjustment, children in the <200 group had lower mean WAZ compared to children >500 (mean difference -0.41; 95% CI -0.60 to -0.21).; In study three, we explored breastfeeding cessation's mediating role in the relationship between maternal CD4 count and infant mortality among 417 uninfected children. We compared the hazard ratio of CD4 count and infant mortality with the hazard ratio further adjusted for breastfeeding cessation. Infants of mothers with CD4 count <200 were at strongly increased risk of death (HR 4.0; 1.6-10.0). After adjusting for breastfeeding cessation, the hazard ratio was reduced from 4.0 to 3.3, a reduction of 23%. These results are consistent with nearly one quarter of the CD4 count-infant mortality association being mediated through breastfeeding cessation.; Children of HIV-infected mothers suffer adverse health outcomes, particularly if infected early or, if uninfected, when born to mothers with advanced disease. These results demonstrate the impact of HIV on children, and add to the ability to identify vulnerable children.