Objective: Acute lower respiratory infections are an important cause of morbidity and mortality in developing countries. Recent randomized trials of zinc supplementation for the prevention of acute lower respiratory tract infections have revealed discrepant findings. The main aim of this study was to evaluate the prevalence of zinc deficiency and the effect of zinc supplementation on respiratory infections.
Material and methods: A single center, prospective open-label interventional single-arm pre-post study of the effect of oral zinc supplementation in zinc deficient children aged 6 months to 5 years was done. A total of 465 healthy children of age 6 months to 5 years were enrolled in the study for estimation of the prevalence of zinc deficiency. Children having zinc deficiency were recruited to study the efficacy and safety of oral administration of 20 mg zinc for two weeks during a 6-month follow-up period.
Results: There were statistically significant differences between the zinc deficient and non-deficient groups according to modified Kuppuswamy categorization of family status and exclusive breast feeding. There was significant difference in the mid arm circumference between the zinc deficient and non-deficient groups (p<0.001). There was significant difference (p<0.001) in the number of episodes of acute upper respiratory infections (AURI), mean duration of AURI, and acute lower respiratory infections (ALRI) between the two groups. There was no significant difference in the ALRI episodes between the two groups. After zinc supplementation in zinc deficient children, there was significant decrease in the number of episodes and mean duration of AURI (p<0.001) and ALRI (p<0.001) within six months after supplementation as compared with the preceding six months before supplementation.
Conclusion: This study reveals that a short course of zinc supplementation may reduce the burden of AURI/ALRI among the zinc deficient children, but larger studies are needed.