Role of Zinc Supplementation in the Outcome of Repeated Acute Respiratory Infections in Indian Children: A Randomized Double blind Placebo-Controlled Clinical Trial

This study was done to determine the role of zinc supplementation in the outcome of acute respiratory infections in Indian children. This prospective, double blind, randomized placebo-controlled trial was conducted with children aged 6 months to 5 years having history of recurrent recent respiratory tract infections. After recruitment, they were randomized to receive 10 mg zinc sulfate or placebo once a day orally for 3 months and were followed monthly up-to next 6 months. Serum zinc concentrations were estimated by colorimetry at the beginning and at the end of 3 months. Zinc supplementation didn't reduce the frequency or duration of respiratory infections overall, but children with post-treatment serum zinc concentrations > 70 mg/dl had significant better outcomes. Usefulness of zinc in improving outcome of ARI in children is an unsolved puzzle and more prospective studies correlating serum zinc concentrations periodically with frequency and duration of ARI in larger cohort are warranted.