Objective: To evaluate the efficacy of zinc supplementation on duration of illness in children with severe acute lower respiratory tract infection (ALRTI).
Methods: This randomized triple-blind placebo-controlled trial was conducted in pediatric emergency of a teaching referral hospital. Children in the age group of 2-24 months presenting to pediatric emergency with severe ALRTI were included. Eligible children were randomly allocated to zinc (n=53) or control (n=53) groups. Zinc group received 20 mg of elemental zinc per day (5 ml syrup per day) as a single daily dose for 5 days. Control group received an equal amount of placebo which was appropriately modified to give the taste, smell, color and consistency similar to zinc mixture. Primary outcome was 'time to be asymptomatic', a composite outcome defined as resolution of all four of the following: danger signs, respiratory distress, tachypnea and hypoxia in room air.
Results: Age, gender, nutritional status, pretreatment zinc levels and other demographic and clinical variables were similar in the two groups. 'Time to be asymptomatic' was comparable in the two groups (h; median (IQR): 60 (24-78) vs. 54 (30-72), P=0.98]. At any time point a similar proportion of children were symptomatic in both the groups. Time to resolution of respiratory distress, tachypnea, dangers signs and hypoxia were also similar in two groups. Duration of hospital stay was shorter by 9 h in the zinc group but the difference was statistically insignificant.
Conclusion: Zinc supplementation did not reduce recovery time and duration of hospital stay in children with ALRTI. Larger randomized controlled trials are needed to evaluate role of zinc in ALRTI.