Background: Asthma and gastro-oesophageal reflux are both common medical conditions and often co-exist. Studies have shown conflicting results concerning the effects of lower oesophageal acidification as a trigger of asthma. Furthermore, asthma might precipitate gastro-oesophageal reflux. Thus a temporal association between the two does not establish that gastro-oesophageal reflux triggers asthma. Randomised trials of a number of treatments for gastro-oesophageal reflux in asthma have been conducted to determine whether treatment of reflux improves asthma.
Objectives: The objective of this review was to evaluate the effectiveness of treatments for gastro-oesophageal reflux in terms of their benefit on asthma.
Search strategy: The Cochrane Airways Group trials register, review articles and reference lists of articles were searched.
Selection criteria: Randomised controlled trials of treatment for oesophageal reflux in adults and children with a diagnosis of both asthma and gastro-oesophageal reflux.
Data collection and analysis: Trial quality and data extraction were carried out by two independent reviewers. Authors were contacted for confirmation or more data.
Main results: Twelve trials met the inclusion criteria. Interventions included proton pump inhibitors (n=6), histamine antagonists (n=5), surgery (n=1) and conservative management (n=1). Treatment duration ranged from 1 week to 6 months. A temporal association between asthma and gastro-oesophageal reflux was investigated in 4 trials and found to be present in a proportion of participants in these trials. Anti-reflux treatment did not consistently improve lung function, asthma symptoms, nocturnal asthma or the use of asthma medications.
Reviewer's conclusions: In asthmatic subjects with gastro-oesophageal reflux, (but who were not recruited specifically on the basis of reflux-associated respiratory symptoms), there was no overall improvement in asthma following treatment for gastro-oesophageal reflux. Subgroups of patients may gain benefit, but it appears difficult to predict responders.