Background: Zinc supplementation has been shown to lower mortality and morbidity due to diarrhea and pneumonia. Because of the positive effect of zinc in the prevention of pneumonia, several studies have been conducted to investigate its effect as an adjunct therapy for pneumonia. For this reason, a systematic, quantitative review of available studies is needed to determine the overall effect of zinc as an adjunct in the treatment of pneumonia in children less than five years old. Objectives: To assess from literature the effect of zinc, when given with antibiotics, in reducing mortality, treatment failure, length of hospital stay, and duration of symptoms of pneumonia in children less than five years old. Design: Meta-analysis of randomized, placebo-controlled intervention trials. Methods: Studies for inclusion were identified by PubMed search, journal handsearch, and other methods. The authors independently assessed study quality and extracted data. Statistical Analysis: Revman Version 4.2 was used to analyze the data gathered. The summary relative risks (RRs) and 95% CI for each outcome variable were estimated using a fixed-effects model. Chi-square and I2 were computed to assess for heterogeneity of results. Results: A total of three acceptable studies were included in the meta-analysis. The summary RRs showed that zinc had no overall treatment effect on mortality from pneumonia (RR 0.69, CI 0.08, 5.70) and treatment failure (RR 1.05, CI 0.74, 1.49). These results were statistically insignificant with p-values of 0.73 and 0.77, respectively. Chi2 and I2 tests showed significant heterogeneity of results for treatment failure (Chi2 = 5.06, I2 = 60.5%). The same tests did not show significant heterogeneity of results for mortality (Chi2 = 0.43, I2 = 0%). In one study, the use of zinc reduced the duration of severe pneumonia with mean difference of four (4.2-4.9) versus five (4.5-5.5) days leading to shorter hospitalization [5 (4.8-5.5) versus six (5.1-6.1) days]. In another study, the zinc group's recovery rate from very ill status was 2.6 times (p = 0.004) more, and the resolution of fever was 3.1 times (p = 0.003) more than those in the placebo group. However, these results could not be combined due to lack of data on standard deviation. Conclusion: There is not enough evidence to conclude that zinc is effective in reducing mortality, treatment failure and duration of symptoms of pneumonia. A large population, multi-center, randomized, placebo-controlled trial should be conducted to obtain statistically significant evidence.
Human ; ZINC ; PNEUMONIA