Zinc supplementation as an adjunct to antibiotics in the treatment of pneumonia in children two to 59 months of age

Gastroenteritis and respiratory infections (particularly pneumonia) are the two most common causes of death in low-income countries. Preventive zinc supplementation may correct any deficiency leading to immunodeficiency and indeed some evidence suggests that preventive zinc supplementation may reduce child mortality and morbidity from infectious diseases, particularly pneumonia. Pnumeonia is the inflammation of the lungs and is caused by viruses, bacteria or other microorganisms. Studies evaluating the impact of zinc supplementation as an adjunct in the management of pneumonia are limited and have shown variable results. The aim of this review is to evaluate the role of zinc supplementation, as an adjunct to antibiotics, in the treatment of pneumonia in children aged two months to 59 months.

The review authors found four randomised control trials of adequate quality evaluating the impact of zinc supplementation as an adjunct to antibiotics for pneumonia in children. These studies were conducted in Bangladesh, Nepal and India, in which 3267 children aged two to 35 months were randomly assigned to receive zinc or placebo. No serious adverse events were observed. Analysis did not show any significant effect on the clinical recovery of patients in terms of time-to-recovery from tachypnoea (respiratory rate > 50 breaths per minute) and time-to-recovery from chest indrawing. It also showed non-significant effects of the intervention on the time-to-hospital discharge. Evidence provided in this review is insufficient to recommend use of zinc as an adjunct to standard antibiotic therapy for pneumonia in children aged two to 35 months.

Authors' conclusions: 

Evidence provided in this review is insufficient to recommend the use of zinc as an adjunct to standard antibiotic therapy for pneumonia in children aged two to 35 months.

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Background: 

Diarrhoeal disorders and acute respiratory infections (ARIs), especially pneumonia, are the most common causes of death in low-income countries. Studies evaluating the impact of zinc supplementation as an adjunct in the management of pneumonia are limited and have shown variable results.

Objectives: 

To evaluate zinc supplementation, as an adjunct to antibiotics, in the treatment (clinical recovery) of pneumonia in children aged two to 59 months.

Search strategy: 

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), which contains the Cochrane Acute Respiratory Infections (ARI) Group's and the Cochrane Infectious Diseases Group's Specialised Registers, MEDLINE (1950 to March week 2, 2011), EMBASE (1974 to March 2011), CINAHL (1981 to March 2011), LILACS (1985 to March 2011), AMED (1985 to March 2011), CAB Abstracts (1910 to March 2011) and Web of Science (2000 to March 2011).

Selection criteria: 

Randomised control trials (RCTs) evaluating supplementation of zinc as an adjunct to antibiotics for pneumonia in children aged two to 59 months.

Data collection and analysis: 

Two review authors independently assessed trial eligibility and screened all available titles and abstracts for inclusion. If the relevance could not be ascertained by screening the title and abstract, we retrieved and reviewed the full text of the article.

Main results: 

We included four trials in which 3267 children aged two to 35 months participated. Analysis showed that zinc supplementation in addition to standard antibiotic therapy in children with severe and non-severe pneumonia failed to show a statistically significant effect on time-to-clinical recovery (hazard ratio 1.02; 95% confidence interval (CI) 0.93 to 1.11). Similary, zinc supplementation in children with severe pneumonia, as an adjunct to standard antibiotic therapy, did not show a statistically significant effect on time-to-recovery from tachypnoea (respiratory rate > 50 breaths per minute) (hazard ratio 1.13; 95% CI 0.82 to 1.57) and time-to-recovery from chest in-drawing (hazard ratio 1.08; 95% CI 0.88 to 1.31) as compared to the control group. Zinc supplementation in children with severe pneumonia also showed a non-significant effect on time-to-hospital discharge as compared to the control (hazard ratio 1.04; 95% CI 0.89 to 1.22).