Vitamin A supplementation and other predictors of anemia among children from Dar es Salaam, Tanzania

The associations of hemoglobin, hematocrit, and packed cell volume with soc ioeconomic factors, malaria, human immunodeficiency virus (HIV) infection, and nutritional status were examined among 687 children admitted to hospita l with pneumonia participating in a double blind, placebo-controlled trial of vitamin A supplementation. Children were randomized to receive 2 doses o f vitamin A (200,000 IU) or placebo at baseline, and additional doses at 4 and 8 months after discharge from hospital. Hemoglobin levels were measured at enrollment and, on a subset of 161 children, during follow-up. At basel ine, hemoglobin concentration was positively associated with the number of possessions in the household, maternal level of education and quality of wa ter supply, and inversely related to malaria infection after controlling fo r potential confounding variables. Children infected with HIV experienced a significant fall in mean hemoglobin levels over time. The risk of developi ng severe anemia (< 7 g/dL) during follow-up was lower for children who wer e breastfed for longer than 18 months as compared to those with less than 6 months of breastfeeding (adjusted prevalence ratio = 0.14, 95% confidence interval [CI] = 0.02, 0.93; P = 0.04), and higher for children over two yea rs of age as compared to 6 to 11 months-old infants (adjusted prevalence ra tio = 8.11, 95% CI = 1.2, 55.8; P = 0.03). Children with repeated diagnoses of malaria had 4.1 times the risk of developing severe anemia than did chi ldren without the diagnosis (95% CI = 1.3, 13.5; P = 0.02). Vitamin A suppl ements were associated with an overall nonsignificant reduction of 14% in t he risk of developing severe anemia (adjusted prevalence ratio = 0.86, 95% CI = 0.37, 1.99; P = 0.73). We conclude that malaria, HIV infection, low so cioeconomic status, and short duration of breastfeeding are strong and inde pendent determinants of adverse hematologic profiles in this population.