Antiretroviral therapy provided to HIV-infected Malawian women in a randomized trial diminishes the positive effects of lipid-based nutrient supplements on breast-milk B vitamins

Background: Little information is available on B vitamin concentrations in human milk or on how they are affected by maternal B vitamin deficiencies, antiretroviral therapy, or maternal supplementation. Objective: The objective was to evaluate the effects of antiretroviral therapy and/or lipid-based nutrient supplements (LNSs) on B vitamin concentrations in breast milk from HIV-infected women in Malawi. Design: Breast milk was collected from 537 women recruited within the Breastfeeding, Antiretrovirals, and Nutrition study at 2 or 6 wk and 24 wk postpartum. Women were assigned to receive antiretrovirals and LNSs, antiretrovirals only, LNSs only, or a control. Antiretrovirals and LNSs were given to the mothers from weeks 0 to 28. The antiretrovirals were zidovudine/lamivudine and nelfinavir or lopinavir/ritonavir. LNSs provided 93-118% of the Recommended Dietary Allowances of thiamin, riboflavin, niacin, pyridoxine, and vitamin B-12. Infants were exclusively breastfed. Results: LNSs increased milk concentrations of all vitamins except thiamin, whereas antiretrovirals lowered concentrations of nicotinamide, pyridoxal, and vitamin B-12. Although antiretrovirals alone had no significant effect on riboflavin concentrations, they negatively affected the LNS-induced increase in this vitamin. Thiamin was not influenced by the study interventions. Concentrations of all B vitamins were much lower than usually accepted values. Conclusions: All B vitamins were low in milk, and all but thiamin were increased by maternal supplementation with LNSs. Antiretrovirals alone decreased concentrations of some B vitamins in milk. When LNS was given in addition to antiretrovirals, the negative effect of antiretrovirals offset the positive effect of LNSs for all vitamins except thiamin.