Efficacy of zinc given as an adjunct to the treatment of severe pneumonia: A meta-analysis of randomized, double-blind and placebo-controlled trials

BackgroundPneumonia is a major cause of morbidity and mortality of children. Zinc is known to play a central role in the immune system. The deficiency of zinc increased susceptibility to infectious diseases. ObjectiveTo investigate the clinical efficacy of zinc given as an adjunct therapy to the treatment of severe pneumonia. MethodsThe PubMed, Embase, MEDLINETM and the Cochrane Central Register of Controlled Trials were searched to identify all randomized, double-blind and placebo-controlled (DBPC) trials which evaluated the clinical efficacy of zinc given as an adjunct in the treatment of severe pneumonia and published between January 1966 and October 2015. ResultsSix randomized DBPC trials including 2216 patients with severe pneumonia were eligible. The results suggested that zinc given as an adjunct therapy to the treatment of severe pneumonia had no significant improvement of treatment failure (RR=0.97, P=.71) and change of antibiotic therapy (RR=1.09, P=.52). We also found a favorable trend for clinical deterioration of severe pneumonia but with no statistical significance (RR=0.88, P=.55). Zinc produced a significant reduction in mortality caused by severe pneumonia (RR=0.43, P=.01). ConclusionsZinc given as an adjunct to the treatment of severe pneumonia is effective in reducing the mortality of severe pneumonia, and has no significant effects on treatment failure and change of antibiotic therapy.