Idiopathic pulmonary fibrosis and gastroesophageal reflux disease: A population-based case-control study

The possible causative role of gastroesophageal reflux disease(GERD)in idiopathic pulmonary fibrosis (IPF)has been quite controversial. Another question is if GERD is a consequence of exaggerated negative intrathoracic pressure in IPF rather than an etiology.The objective of this population-based study was to investigate if patients with IPF were at increased risk of GERD exposure(within 5 years prior to the diagnosis) compared to age and sex matched two groups of controls.The two groups of controls were: interstitial lung disease(ILD)other than IPF and subjects with no diagnosed lung disease (population controls).Rochester Epidemiology Project (REP)was used to identify cases of IPF as well as controls (matching between cases and controls 1:2).American Thoracic Society/European Respiratory Society criteria for the diagnosis of IPF were used.A total of 113 IPF cases were identified between Jan 1, 1997 and Jun 30, 2017.When comparing IPF cases with population controls the odds of being exposed to GERD was 1.80(95% CI 1.11-2.93,p-value 0.02)times higher in IPF patients after multivariable adjustments. When comparing with non-IPF controls the odds of GERD were 0.60 times lower(95% CI =0.35-1.03,p=0.06) after multivariable adjustment.This comparison did not reach statistical significance.We conclude from this study when compared to the population control, patients with IPF were at significantly increased risk to have exposure to GERD. This difference was not observed when IPF was compared to non-IPF ILD.GERD can be one of the important contributors to the development of lung fibrosis,it should be addressed adequately when detected in patients with pulmonary fibrosis especially IPF.