O7.7 Gastro-oesophageal reflux disease (GORD)

In patients with COPD, hyperinflation, coughing and the increased negative intrathoracic pressures of inspiration may predispose to reflux, especially during recumbency and sleep. Microaspiration of oesophageal secretions (possible including refluxed gastric content) is a risk, especially with coexistent snoring or OSA. Reflux and microaspiration exacerbate cough, bronchial inflammation and airway narrowing. A nested case control study performed on a large primary care dataset found a modest increased risk of gastro-oesophageal reflux in patients with a pre-existing diagnosis of COPD (RR 1.46 CI 1.19-1.78)(Garcia Rodriguez 2008) although higher relative risks have been reported in other studies and Sakae et al reported a RR of 13.06 (95% CI 3.64-46.87) in their systematic review and meta-analysis of exacerbations of COPD and symptoms of GORD. In a large cross-sectional study of patients with a wide range of COPD severity, forming part of the US COPD Gene Study, 29% of patients reported a diagnosis of physician-diagnosed GORD (Martinez 2014). In this study, GORD symptoms were associated with worse health related quality of life (HRQOL) (SGRQ), increased dyspnoea and more frequent exacerbations. Two of these three associations persisted after adjusting for the use of proton pump inhibitors (PPI) (although the latter was associated with an improvement in HRQOL). It is noted that PPI use in the general population is associated with a higher frequency of pneumonia (Gulmez 2007, Eurich 2010). Nonetheless, other studies have suggested PPI use is associated with a reduction in exacerbations in GORD-sufferers (Sakae 2013, Sasaki 2009). In the study by Martinez et al, subjects with GORD were more likely to be female, to have symptoms of chronic bronchitis and to have a higher prevalence of cardiovascular disease. Over two years of follow-up the presence of GORD symptoms was associated with more frequent exacerbations which was not altered by PPI use. ln another prospective cohort study, gastro-oesophageal reflux symptoms were associated with an increased risk of exacerbation (Terada 2008). Prospective data from users of inhaled medications in the COPDGene cohort has shown that GORD is a common risk factor for COPD exacerbations across all medication groups except for those using only short-acting bronchodilator medications. Female gender was an independent risk factor across all groups (Busch 2016).

Further large prospective studies would seem to be required to clarify the relationships between GORD, its treatment and COPD exacerbations. Diagnosis may be confirmed by 24-hour monitoring of oesophageal pH, modified barium swallow or gastroscopy. However, a therapeutic trial of therapy with H2-receptor antagonists or a proton-pump inhibitor may obviate the need for invasive investigations. Lifestyle changes, including stopping smoking, limiting food intake within 4 hours of bed-time, reduced intake of caffeine and alcohol, weight loss and exercise, will also help. Elevation of the head of the bed is also recommended.