Symptom response to antibiotic prescribing strategies in acute sore throat in adults: the DESCARTE prospective cohort study in UK general practice.

BACKGROUND: A delayed or 'just in case' prescription has been identified as having potential to reduce antibiotic use in sore throat. AIM: To determine the symptomatic outcome of acute sore throat in adults according to antibiotic prescription strategy in routine care. DESIGN AND SETTING: A secondary analysis of the DESCARTE (Decision rule for the Symptoms and Complications of Acute Red Throat in Everyday practice) prospective cohort study comprising adults aged >/=16 years presenting with acute sore throat (</=2 weeks' duration) managed with treatment as usual in primary care in the UK. METHOD: A random sample of 2876 people from the full cohort were requested to complete a symptom diary. A brief clinical proforma was used to collect symptom severity and examination findings at presentation. Outcome details were collected by notes review and a detailed symptom diary. The primary outcome was poorer 'global' symptom control (defined as longer than the median duration or higher than median symptom severity). Analyses controlled for confounding by indication (propensity to prescribe antibiotics). RESULTS: A total of 1629/2876 (57%) of those requested returned a symptom diary, of whom 1512 had information on prescribing strategy. The proportion with poorer global symptom control was greater in those not prescribed antibiotics 398/587 (68%) compared with those prescribed immediate antibiotics 441/728 (61%) or delayed antibiotic prescription 116/197 59%); adjusted risk ratio (RR) (95% confidence intervals [CI]): immediate RR 0.87 (95% CI = 0.70 to 0.96), P = 0.006; delayed RR 0.88 (95% CI = 0.78 to 1.00), P = 0.042. CONCLUSION: In the routine care of adults with sore throat, a delayed antibiotic strategy confers similar symptomatic benefits to immediate antibiotics compared with no antibiotics. If a decision is made to prescribe an antibiotic, a delayed antibiotic strategy is likely to yield similar symptomatic benefit to immediate antibiotics.