Risk factors for interstitial lung abnormalties identified on computed tomography pulmonary artery protocol: a retrospective study

SESSION TITLE: Diffuse Lung Disease Posters 3 SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/10/2023 12:00 pm - 12:45 pm PURPOSE: Interstitial lung abnormalities (ILAs) are radiographic findings in otherwise asymptomatic indiviuals that have a myriad of potential implications. The identification of ILAs is associated with increased morbidity and mortality [1]. A subset of patients have progressive interstitial lung disease. Established risk factors include age >50 years, male sex, smoking status and presence of MUC5B gene variant [2]. Recurrent aspiration due to disruptions in oropharyngeal mechanics has been implicated in interstitial lung disease, however not in the development of ILAs [3]. We postulate risk factors associated with compromised airway clearance contribute to ILA development. METHODS: This is a retrospective review of computed tomography with pulmonary angiography (CTPA) scans obtained in two Emergency Departments (EDs) between May 2009 and July 2010. The reviewer (RG) identified scans with presumed ILAs, which were then examined by an ILD Pulmonologist (PC). If there were discrepancies, then the scan in question was reviewed by a chest radiologist (ZK). Medical Records were reviewed to identify comorbid conditions, smoking status, age, sex, and medications. Aspiration and dysphagia were identified in patients who had debris in airways on imaging or a barium swallow study that was consistent with impaired oropharyngeal mechanics. Obstructive Sleep Apnea (OSA) was identified only in patients in whom a sleep study had been performed. RESULTS: We reviewed 990 charts and identified 383 patients who had follow-up CT scan with or without contrast at least 1 year after the original. 31/383 patients had ILA on initial imaging. 10/31 (32.3%) vs 115/354 (32.5%) had a diagnosis of obstructive sleep apnea in the ILA group and non-ILA group respectively. Hiatal hernias were present in 12/31 (38.7%) vs 45/354 (12.7%) in the ILA and non-ILA groups respectively. The rate of aspiration or dysphagia in those with ILA was twice that of the non-ILA group, 8/31 (25.8%) vs 43/354 (12.1%). CONCLUSIONS: In this retrospective study, we analyzed 383 patients with CTPAs. Our results suggest that disruptions in the gastro-oropharyngeal axis may pose an additional risk to the development of ILAs. More than a third of patients with ILAs had a hiatal hernia, and half of those patients had sleep apnea. Whereas only 12.7% of individuals without ILA had hiatal hernias. A higher proportion of patients in the ILA group were on medications for gastroesophageal reflux and had swallow studies suggestive of dysphagia or aspiration. Interestingly, established risk factors such as male sex (32.3% vs 32.6%, ILA vs non-ILA) and smoking status (35.5% vs 33.6%) did not seem to influence radiographic findings. Further evaluation in a larger patient population with ILAs is needed to bolster this claim. CLINICAL IMPLICATIONS: 1. Putman, R.K., et al., Association Between Interstitial Lung Abnormalities and All-Cause Mortality. JAMA, 2016. 315(7): p. 672-81. 2. Hatabu, H., et al., Interstitial lung abnormalities detected incidentally on CT: a Position Paper from the Fleischner Society. Lancet Respir Med, 2020. 8(7): p. 726-737. 3. Lee, A.S., et al., Reflux-Aspiration in Chronic Lung Disease. Ann Am Thorac Soc, 2020. 17(2): p. 155-164. DISCLOSURES: Consultant relationship with BD Please note: $5001 - $20000 by Joseph Bledsoe, value=Consulting fee Advisory Committee Member relationship with Baxter Health Please note: 11/4-11/21 2022 Added 03/29/2023 by Joseph Bledsoe, source=Web Response, value=Honoraria No disclosure on file for Peter Crossno I received research funds from the entit relationship with Janssen Pharmaceuticals Please note: 10/1/2019-9/30/2022 Added 03/29/2023 by Mark Dodson, source=Web Response, value=Grant/Research No relevant relationships by C Elliott No relevant relationships by Ryan Gil No relevant relationships by Daniel Knox No disclosure on file for Zachary Krahn No relevant relationships by Brittany Scarpato