Growth of infants born to HIV-infected women in South Africa according to maternal and infant characteristics

OBJECTIVE To evaluate growth parameters assessed by weight and length in HIV-infected and HIV-uninfected infants born to HIV-infected mothers in South Africa from birth to 6 months of age. METHODS We calculated z-scores for weight-for-age (WAZ), length-for-age (LAZ) and weight-for-length (WLZ) among a cohort of 840 mother-infant dyads. Multivariable Cox proportional hazards models with time-varying covariates were used to estimate the risk of falling <- 2 z-scores for WAZ, LAZ, and WLZ as a function of infant and maternal characteristics. RESULTS By 6 months after birth, a fifth of infants had WAZ <- 2, 19% had an LAZ <- 2, and 29% had a WLZ <- 2. WLZ and WAZ were significantly lower in HIV-infected infants than in uninfected infants by 3 months of age and LAZ by 6 months of age (P < 0.001). The risk of WAZ falling <- 2 was associated with decreasing maternal CD4 cell count (adj. HR for CD4 cell count < 200 cells/mu l: 1.64; 95% CI: 1.10-2.43), premature birth (adj. HR: 2.82; 95% CI: 2.06-3.86) and formula feeding (adj. HR: 3.35; 95% CI: 1.64-6.85). The risk of LAZ falling <- 2 was associated with increasingly lower maternal age (adj. HR for <20 years: 0.54; 95% CI: 0.31-0.96), lower maternal CD4 cell count (adj. HR for CD4 cell count < 200 cells/mu l: 1.72; 95% CI: 1.14-2.59), premature birth (adj. HR: 2.37; 95% CI: 1.70-3.30) and formula feeding (adj. HR: 4.22; 95% CI: 1.85-9.62). The risk of WLZ falling <- 2 was significantly associated with infant HIV infection (adj. HR: 1.64; 95% CI: 1.16-2.32) and formula feeding (adj. HR: 1.78; 95% CI: 1.11-2.83). The risk of WAZ and LAZ falling <- 2 was more than two times greater for HIV-infected infants than for uninfected infants with gastrointestinal infections. CONCLUSIONS HIV-infected infants were more likely to be stunted and wasted than uninfected infants, which often occurred within 3 months after birth. Infants who were born to mothers with advanced HIV disease, formula-fed and co-infected with HIV and gastrointestinal infections were at greater risk for growth disturbances. Further interventions are needed to promptly initiate both HIV-infected mothers and infants on appropriate antiretroviral therapy and nutritional supplementation.