Background: The vicious cycle hypothesis for bronchiectasis predicts that bacterial colonisation of the respiratory tract perpetuates inflammatory change. This damages the mucociliary escalator preventing bacterial clearance and allowing the persistence of pro-inflammatory mediators. Conventional treatment with physiotherapy and intermittent antibiotics are felt to improve the condition of bronchiectasis patients although there are no conclusive data showing that these interventions influence the natural history of the condition. Various strategies have been tried to interrupt this cycle of infection and inflammation and one of these is to prolong antibiotic treatment in the hope of allowing the airway mucosa to heal.
Objectives: This systematic review brings together the evidence and where possible presents a meta-analysis of the data available to answer the question 'Does treatment with prolonged courses of antibiotics influence the outcome in purulent bronchiectasis?'
Search strategy: The Cochrane Airways Group trials register and reference lists of identified articles were searched. Searches were current as of January 2007.
Selection criteria: Randomised trials looking at the use of prolonged antibiotic therapy in the treatment of bronchiectasis compared with either placebo or usual care.
Data collection and analysis: Trial quality was assessed and data extraction was carried out by the reviewers independently. Study authors were contacted for missing information.
Main results: Nine trials met the inclusion criteria, recruiting a total of 378 participants. Antibiotics were given for between 4 weeks and one year. Only limited meta-analysis was possible due to the diversity of outcomes in the trials. Response rates showed significant effects in favour of prolonged antibiotic treatment (Peto OR (95% CI), 3.37 (1.60 to 7.09)). Conversely for exacerbation rates there was no significant difference between prolonged antibiotics and placebo (Peto OR (95% CI), 0.96 (0.27 to 3.46)). For withdrawals there was no significant difference between treatment and placebo management (Peto OR (95% CI), 1.06 (0.42 to 2.65)). Data for lung function showed no significant benefit in favour of antibiotic treatment (% predicted FEV1 mean difference -1.05 % (95% CI -6.93 to 4.83)).
Authors' conclusions: The evidence available shows a small benefit for the use of prolonged antibiotics in the treatment of bronchiectasis. This review is limited by the diversity of the trials. Further randomised controlled trials with adequate power and standardised end points are required.