Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD)

There has been renewal of interest in the use of prophylactic antibiotics to reduce the frequency of exacerbations and improve quality of life in chronic obstructive pulmonary disease (COPD). To determine whether or not regular treatment of COPD patients with prophylactic antibiotics reduces exacerbations or affects quality of life. We searched the Cochrane Airways Group Trials Register and bibliographies of relevant studies. The latest literature search was August 2013. Randomised controlled trials (RCTs) that compared prophylactic antibiotics with placebo in patients with COPD. We used the standard methods of The Cochrane Collaboration. Data were extracted and analysed by two independent review authors. Seven RCTs involving 3170 patients were included in this systematic review. All studies were published between 2001 and 2011. Five studies were of continuous antibiotics and two studies were of intermittent antibiotic prophylaxis (termed 'pulsed' for this review). The antibiotics investigated were azithromycin, erythromycin, clarithromycin and moxifloxacin. Azithromycin, erythromycin and clarithromycin are macrolides while moxifloxacin is a fourth-generation synthetic fluoroquinolone antibacterial agent. The study duration varied from three months to 36 months and all used intention-to-treat analysis. Most of the results were of moderate quality. The risk of bias of the included studies was generally low, and we did not downgrade the quality of evidence for risk of bias.The trials recruited participants with a mean age of 66 years and with at least a moderate severity of COPD. Three trials included participants with frequent exacerbations and two trials recruited participants requiring systemic steroids or antibiotics, or both, or who were at the end stage of their disease and required oxygen.The primary outcomes for this review were the number of exacerbations and quality of life.With use of continuous prophylactic antibiotics the number of patients experiencing an exacerbation was reduced (odds ratio (OR) 0.55; 95% confidence interval (CI) 0.39 to 0.77, 3 studies, 1262 participants, high quality). This represented a reduction from 69% of participants in the control group compared to 54% in the treatment group (95% CI 46% to 63%) and the number needed to treat to prevent one exacerbation (NNTb) was therefore 8 (95% CI 5 to 18). The frequency of exacerbations was also reduced with continuous prophylactic antibiotic treatment (rate ratio 0.73; 95% CI 0.58