Clinical approach to gastro-oesophageal reflux in idiopathic pulmonary fibrosis

Abstract

Idiopathic pulmonary fibrosis is a progressive condition with limited treatment options and median survival of 3-5 years. Gastro-oesophageal reflux (GOR) has been described in up to 90% of patients. Pulmonary aspiration has been suggested to contribute to IPF, with calls for aggressive antireflux therapy. Whilst medical therapy can usually control acid reflux, surgery may be required to control non-acid refluxate, which may also be harmful if aspirated into the lung. The risks of surgery in the IPF population are significant. There is no validated technique with which to measure aspiration in this group and furthermore, patient attitudes towards the treatment of reflux and aspiration in IPF are unknown. As a result, the population that might benefit from antireflux therapy has yet to be defined. The current study comprised two main aims. The first was to characterise reflux and aspiration in an IPF cohort. The second was to evaluate patient attitudes towards the burden of IPF disease as compared to the burden of antireflux therapy. Methods Symptoms of reflux and lung health were assessed using a panel of structured questionnaires. Oesophageal function and gastro-oesophageal reflux were objectively assessed using manometry and pH-impedance monitoring. A standardised bronchoscopy and bronchoalveolar lavage, with biochemical and cytological analysis, was used to assess pulmonary aspiration. A separate group of individuals with IPF participated in an interview study. Respondents’ own health was evaluated using a visual analogue scale, the EuroQOL-5D -3L survey and a standard gamble utility analysis. Vignettes were constructed to describe mild- and moderate-severity IPF health states and adverse outcomes from medical and surgical antireflux therapy. Patient attitudes towards these four health states were assessed with a ranking exercise and a series of standard gambles. Results pH-impedance monitoring demonstrated supranormal levels of gastro-oesophageal reflux in 22 of 36 study subjects (61%). Eleven subjects had pre-existing evidence of gastro- ii oesophageal reflux and questionnaire assessment suggested GORD in 29% of subjects. Oesophageal manometry identified abnormal oesophageal function in 56%. Supranormal levels of pepsin were detected in bronchoalveolar lavage fluid in 16 subjects. The combination of pepsin quantification and oesophageal monitoring identified a subgroup of subjects with evidence of reflux and aspiration, but there was no correlation between levels of reflux and pepsin concentrations. Cytological staining results correlated poorly with gastro-oesophageal reflux. After formal multidisciplinary review, two patients who participated in the current study have undergone fundoplication. Both have enjoyed a stable disease course since surgery. In the interview study, respondents recorded mean utilities of 0.611 to 0.798 for their own health. Amongst 59 respondents, 38 regarded both IPF health states as preferable to the outcomes of either antireflux therapy outcome; the remainder disagreed. An adverse outcome from antireflux surgery was generally regarded as the worst of the health states. Discussion Oesophageal physiology and BAL fluid analysis may be combined to investigate reflux and aspiration in IPF. The current data suggest that reflux is common and frequently asymptomatic. Aspiration may only be significant in the minority of patients. Oesophageal dysmotility, a relative contra-indication to fundoplication, was evident in the majority of subjects. This is the first report of health state utilities for IPF and demonstrates a disease burden comparable to advanced lung cancer. Opinion was divided as to the relative burden associated with IPF disease and the potential outcomes of antireflux therapy. In conclusion, it remains difficult to identify the IPF patients for whom antireflux surgery might be most beneficial. For a proportion, the risks of such treatment will be prohibitive. The complexity of surgical decisions in this group suggests a requirement for a standard of care that includes a multidisciplinary team, informed by objective aerodigestive physiology and imaging.