TOPIC: Diffuse Lung Disease TYPE: Original Investigations PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial pneumonia that has been shown to have an association with gastroesophageal reflux disease (GERD) possibly due to chronic micro-aspiration leading to remodeling of the lung parenchyma. While a causal relationship between these two pathologies has not been clearly demonstrated to date, prior studies suggest they are closely related with GERD being more common in IPF than the general population. This study sought to further investigate the potential link between GERD and IPF as well as characterize sources of inpatient mortality in patients with concurrent disease. METHODS: Data from the National Inpatient Sample (NIS) database for 2015-2016 was used to assess the prevalence of IPF and the major causes of inpatient mortality in patients with both GERD and IPF. All hospitalizations with GERD (ICD-10-CM K21.0 and K21.9) were analyzed. Univariate and multivariate logistic regression analyses were performed and was adjusted for age, sex, race. SPSS was used for data analysis. RESULTS: There were 6,304,222 admissions among individuals with GERD from 2015 to 2016 with 49,870 patients also having concomitant IPF. The mean age was 72.77 years with 52.7% of patients between ages 61 to 80. Some of the comorbidities with corresponding prevalences in those with both GERD and IPF included: emphysema (2.8%), pulmonary hypertension (PAH) (17.1%), chronic obstructive pulmonary disease (COPD) (44.6%), asthma (11.3%), tobacco use (6.7%), achalasia (0.3%), and diaphragmatic hernia (5.7%). Of those with concomitant dieases, 4.2% suffered in-hospital mortality. Male sex (OR 1.190; 95% CI 1.173-1.207) was observed to have an increased risk of mortality and well as those with concomitant emphysema (OR 1.391; 95% CI 1.287-1.505), PAH (OR 1.762; 95% CI 1.709-1.817), COPD (OR 1.468; 95% CI 1.445-1.492), PE (OR 2.362; 95% CI 2.263-2.465), heart failure (OR 2.354; 95% CI 2.318-2.391) and systemic sclerosis (OR 1.737; 95% CI 1.546-1.953) but not with hypertension (OR 0.964; 95% CI 0.949-0.979), diaphragmatic hernia (OR 0.580; 95% CI 0.556-0.605), tobacco use (OR 0.441; 95% CI 0.428-0.454), and OSA (OR 0.463; 95% CI 0.448-0.479). The average length of stay was also higher in patients with GERD and coexisting IPF compared to those without IPF (4.4 days versus 5.2 days). CONCLUSIONS: Current data shows that there is an association between GERD and IPF, however, there is limited data regarding the demographics, distribution of significant comorbidities, and clinical outcomes of patients who have GERD and IPF simultaneously. Of those with both diseases, the majority of them were females above the age of 60 years and there was increased in-hospital mortality in those with concomitant emphysema, PAH, PE, heart failure and systemic sclerosis but not with hypertension, diaphragmatic hernias, diabetes or hypothyroidism. Further studies will be needed to explore how treatment of GERD in the setting of IPF may improve complication rates. CLINICAL IMPLICATIONS: Although a causal relationship between GERD and IPF has not been clearly established, our findings add to the growing knowledge that those with these simultaneous diseases are at higher risk for poor outcomes while in-hospital. DISCLOSURES: No relevant relationships by Andrew Berman, source=Web Response No relevant relationships by Konstantinos Damiris, source=Web Response No relevant relationships by Thomas Ng, source=Web Response No relevant relationships by Emily Seltzer, source=Web Response No relevant relationships by Melissa Wing, source=Web Response