C54-20 Outcomes of Sepsis in Patients With Interstitial Lung Disease: A National Inpatient Sample Analysis, 2018-2022

Abstract Rationale Patients with interstitial lung disease (ILD) frequently develop severe infections, but contemporary, nationally representative estimates of sepsis outcomes in ILD are limited. Methods We conducted a cross-sectional analysis using the National Inpatient Sample (NIS) from 2018-2022. Sepsis discharges were identified using validated ICD-10-CM/PCS algorithms. ILD exposure was defined by any secondary or primary ILD diagnosis. Survey procedures reproduced national estimates (pweight = DISCWT; strata = NISSTRATUM; PSU = HOSPID). Between-group differences were evaluated using design-based χ² or F tests. Survey-weighted logistic regression estimated adjusted associations of ILD (yes vs. no) with in-hospital mortality and complications—including ARDS, invasive mechanical ventilation, renal replacement therapy (RRT), tracheostomy, and extracorporeal membrane oxygenation (ECMO). Length of stay (LOS) was modeled using survey-weighted negative binomial regression (incidence rate ratio, IRR), and total hospital charges (inflation-adjusted to 2022 USD) with a Gamma log-link model (cost ratio, CR). Models adjusted for age (linear and quadratic), sex, race/ethnicity, payer, ZIP-code income quartile, weekend admission, census region, hospital characteristics, infection source, and year fixed effects. Two-sided p 0. 05 denoted statistical significance. Results Among an estimated 13. 6 million sepsis hospitalizations, 131, 465 (1. 0%) involved patients with ILD. ILD patients were older (mean 72. 9 vs. 64. 7 years) and more often Medicare-insured (74. 5% vs. 59. 6%). Pulmonary infection sources were more frequent in ILD (67. 3% vs. 42. 4%) (all p 0. 001). Unadjusted in-hospital mortality was higher in ILD (22. 1% vs. 13. 2%, p 0. 001). After adjustment, ILD remained associated with increased mortality (OR 1. 28, 95% CI 1. 25-1. 33; AME +2. 94 percentage points). ILD was also associated with greater odds of ARDS (OR 1. 93), mechanical ventilation (OR 1. 05), tracheostomy (OR 1. 32), and ECMO (OR 4. 30), but lower odds of RRT (OR 0. 61) (all p ≤ 0. 001). ILD was associated with longer LOS (IRR 1. 11) and higher total charges (CR 1. 16). Median LOS was 6 (IQR 4-12) vs. 6 (IQR 3-10) days, and median charges were 70, 977 vs. 59, 805, respectively. Conclusions Among U. S. hospitalizations for sepsis, the presence of interstitial lung disease identifies a distinct high-risk phenotype, characterized by approximately 28% higher adjusted odds of death, nearly doubled odds of ARDS, and substantially higher use of advanced respiratory support, including tracheostomy and ECMO. These patients also experience longer hospitalizations and higher costs. Early recognition of respiratory decompensation, lung-protective ventilation strategies, and proactive goals-of-care discussions are warranted. Future research should delineate ILD subtype-specific risks and assess tailored sepsis management pathways for this population. This abstract is funded by: None