The natural history of acute cough in children aged 0 to 4 years in primary care: a systematic review.

Professional and parental uncertainty regarding the natural history of cough and respiratory tract infection (R77) in pre-school children may in part be responsible for the high consultation, reconsultation, and antibiotic prescribing rates in this age group. The aim of the study was to review the evidence about the natural history of acute cough in children aged between 0 and 4 years presenting to primary care in terms of illness duration and complications. The study was a systematic review, with qualitative and quantitative data synthesis, of control and placebo arms of systematic reviews, randomised controlled trials (RCTs), and cohort studies set in primary care. Searches were done of MEDLINE (between 1966 and June 1998), EMBASE (between 1988 and September 1998), and the Cochrane Library databases, using the MeSH terms 'respiratory tract infection, 'cough, and 'bronchitis, and the textwords 'cough' 'bronchitis, and 'chest infection, limited to children aged between 0 and 4years, and English language articles. Eight RCTs and two cohort studies met the review criteria. At one week, 75% of children may have improved but 50% may be still coughing and/or have a nasal discharge. At two weeks up to 24% of children may be no better. Within two weeks of presentation, 12% of children may experience one or more complication, such as rash, painful ears, diarrhoea, vomiting, or progression to bronchitis/pneumonia. This review offers parents and clinicians more prognostic information about acute cough in pre-school children. Illness duration may be longer and complications higher than many parents and clinicians expect. This may help to set more realistic expectations of the illness and help parents to decide when and if to reconsult. This information may be useful to those designing patient information and self-help resources.