Impact of zinc supplementation on persistent diarrhoea in malnourished Bangladeshi children

Abstract

To evaluate the impact of zinc supplementation on the clinical recovery and body weight of children with persistent diarrhoea, a randomized, double-blind, controlled trial was conducted in 190 children with persistent diarrhoea aged between 3 and 24 months. Children were randomly allocated to receive either zinc (20 mg d(-1)) syrup with multivitamin (2 x RDA) or multivitamin alone in three divided daily doses for 2 weeks. The trial was conducted in a diarrhoeal disease hospital in Dhaka, Bangladesh. Duration until clinical recovery (d), impact on body weight and serum zinc level after 2 weeks of zinc supplementation were recorded. The duration of illness was significantly reduced (33%) with zinc supplementation among children who were underweight (< or =70% wt/age, p = 0.03). Supplemented male children also had a significant reduction (27%) in duration for recovery compared with unsupplemented children (p = 0.05). From baseline to convalescence, zinc-supplemented children maintained their serum zinc concentration (13.4 vs 13.6 micromol l(-1)), whereas unsupplemented children had a decrease in serum zinc after the 2 weeks of diarrhoea (13.6 vs 11.8 micromol l(-1),p < 0.03). The mean body weight of the children in the supplemented group was maintained (5.72 vs 5.70 kg, p = 0.62) during hospitalization, unlike that of the control group, in which there was a reduction in body weight (5.75 vs 5.67 kg, p = 0.05). Five children in the unsupplemented group and one child in the zinc-supplemented group died during the 2 weeks of supplementation (p = 0.06). Zinc supplementation in persistent diarrhoea significantly reduced the length of the recovery period in malnourished children and prevented a fall in body weight and serum zinc concentration, indicating that zinc is a beneficial therapeutic strategy in this high-risk childhood illness.