Meta-analysis: zinc supplementation for acute gastroenteritis in children.

BACKGROUND Uncertainty exists regarding the use of zinc in the treatment of acute gastroenteritis in children living in Europe, where zinc deficiency is rare. AIM To review evidence for the effectiveness of zinc in treating acute gastroenteritis in children, with special emphasis on data from developed countries. METHODS MEDLINE, EMBASE, and the Cochrane Library were searched through November 2007 for randomized controlled trials (RCTs) relevant to acute gastroenteritis in children younger than 5 years of age and zinc; additional references were obtained from the reviewed articles. RESULTS Eighteen RCTs (11,180 participants, mainly from developing countries) met the inclusion criteria. Use of zinc was associated with a significant reduction in diarrhoea duration (13 RCTs, 5643 infants, weighted mean difference -0.69 day, 95% CI -0.97 to -0.40) and the risk of diarrhoea lasting longer than 7 days [eight RCTs, n = 5769, relative risk (RR) 0.71, 95% CI 0.53-0.96]. No significant reduction in stool volume was observed for those receiving zinc compared with placebo (three RCTs, n = 606, standardized mean difference, -0.38, 95% CI -1.04 to 0.27). Combined data from five RCTs (n = 3156) showed that zinc significantly increased the chance of vomiting compared to the control agent (RR 1.2, 95% CI 1.05-1.4). CONCLUSIONS These data confirm that zinc supplementation can be useful for treating acute gastroenteritis in children, particularly those from developing countries. However, the role of zinc supplements in treating children with acute gastroenteritis in developed countries needs further evaluation.