Background: Cough is the most common symptom which presents to doctors. Chronic cough is reported in up to 9% of preschool aged children. American general practice guidelines suggest antimicrobial treatment may be indicated in children with cough lasting > 10 days. Questions concerning the benefits and harm of antibiotic treatment for prolonged cough in children need to be resolved.
Objectives: A Cochrane systematic review was undertaken to determine the efficacy of antibiotics in treating children with chronic moist cough (excluding those with bronchiectasis or other underlying respiratory illnesses).
Search strategy: The Cochrane Register of Controlled Trials (CENTRAL), the Cochrane Airways Group Specialised Register, MEDLINE, EMBASE, review articles and reference lists of relevant articles were searched. The latest searches were performed on 12th April 2004.
Selection criteria: All randomised controlled trials (RCTs) comparing antibiotics with a placebo or a control group in children with chronic moist cough were considered.
Data collection and analysis: Results of searches were reviewed against pre-determined criteria for inclusion. Two independent reviewers selected, extracted and assessed the data for inclusion. Authors were contacted for further information. Data were analysed as 'intention to treat'.
Main results: Two studies were eligible for inclusion in the review. Neither study was high quality. Both studies failed to include a prospective analysis of cough quality in their inclusion criteria, although indicating >75% of children included had moist cough (Darelid 1993). A total of 140 patients, aged seven years or less, were included in meta-analysis. Treatment with antibiotics reduced the proportion of children not cured at follow-up (primary outcome measure) in both studies; pooled odds ratio (OR) was 0.13, 95% CI 0.06 to 0.32 (using intention to treat analysis), which translates to number needed to treat (NNT) of 3 (95% CI 2 to 4). No significant heterogeneity was found (fixed and random-effects model I(2) was 4%). However for this outcome measure, the overall estimate of effect and degree of statistical heterogeneity were sensitive to the model used for meta-analysis. Progression of illness, defined by requirement for further antibiotics, was significantly lower in the treatment group (OR 0.10, 95%CI 0.03 to 0.34), NNT was 4 (95% CI 3 to 5). Adverse events were not significantly increased in the treatment group.
Authors' conclusions: Antibiotics are likely to be beneficial in the treatment of children with chronic moist cough. This evidence is however limited by study quality, study design and sensitivity analysis data. The use of antibiotics however has to be balanced against their well known adverse events. Further well-designed RCTs using valid cough outcome measures are needed to answer this question conclusively.