RESUMO
OBJECTIVE: To compare the effects of a biologically and chemically acidified formula with or without probiotics with a standard formula on growth of infants negative for human immunodeficiency virus (HIV). METHODS: This was a double-masked, randomized, clinical trial. Infants born to consenting HIV-positive women who had decided not to breast-feed before being approached for participating in the study were randomized to receive one of four milk formulas: a chemically acidified formula with or without probiotics (Bifidobacterium lactis), a biologically acidified formula, or a standard whey formula. Infants who subsequently became HIV-positive according to polymerase chain reaction at 6 wk were excluded. Their growth and biochemical status were monitored for 4-6 mo. The z scores at the last visit of infants in each of the four formula groups were compared using analysis of covariance correcting for the z scores at baseline. Blood gases and pH were analyzed using a two-way analysis of variance corrected for center. RESULTS: One hundred thirty-two HIV-negative infants were monitored for growth and biochemical parameters for 4-6 mo. There was an improvement of z scores for all formulas, and there were no differences in weight for age (P = 0.22), length for age (P = 0.56), head circumference for age (P = 0.66), or weight for length (P = 0.13). There were no differences in blood pH and biochemical parameters among the formula groups. CONCLUSION: The growth of infants fed one of the three acidified formulas was not inferior to the standard formula. Growth and metabolism in HIV-negative infants fed the acidified formulas were not affected by the method of milk acidification.
