A105-14 Neighborhood-level Disadvantages Are Associated With Adverse CTD-ILD Outcomes

Abstract Rationale Connective tissue diseases (CTDs) are a heterogeneous group of systemic autoimmune rheumatologic disorders. Interstitial lung disease (ILD) is a major cause of morbidity and mortality among patients with CTD. Neighborhood-level disadvantage is increasingly recognized as an important determinant of health outcomes. In the United States, composite indices such as the Area Deprivation Index (ADI) and Social Vulnerability Index (SVI) are widely used to characterize socioeconomic and demographic conditions at the neighborhood level. Prior studies have demonstrated associations between neighborhood disadvantage and outcomes in idiopathic pulmonary fibrosis; however, these analyses were limited by relatively small sample sizes and included few patients with CTD-ILD. Large, real-world studies in CTD-ILD have not been conducted. Methods We evaluated the association between ADI, SVI, health-care utilization patterns, and clinical outcomes using the Epic Cosmos database. This retrospective cohort study included adults ≥18 years with CTD-ILD between 01/01/2016 and 12/31/2020 (N = 30,235), identified using ICD-10 codes. Zero-inflated negative binomial regression with robust standard errors was used to assess the association between ADI and count outcomes (hospital admissions and emergency department ED visits). All-cause mortality was assessed using logistic regression. Multivariable models adjusted for age, race, sex, BMI, smoking status, Elixhauser comorbidities, and Medicaid use. Results Higher neighborhood disadvantage was independently associated with worse clinical outcomes. All-cause mortality increased by 8% per 10-unit increase in ADI (adjusted odds ratio aOR 1.08; 95% CI, 1.06-1.10). Higher SVI was similarly associated with mortality (per 0.1-unit increase: aOR 1.04; 95% CI, 1.02-1.06). ED visits increased by 5% per 10-unit increase in ADI (adjusted incidence rate ratio aIRR 1.05; 95% CI, 1.04-1.06) and by 7% per 0.1-unit increase in SVI (aIRR 1.07; 95% CI, 1.06-1.08). Although the indices were moderately correlated, ADI demonstrated slightly stronger associations with mortality, whereas SVI showed larger associations with utilization outcomes. Conclusions In a large real-world cohort of CTD-ILD patients, increasing neighborhood-level disadvantage measured by ADI and SVI was associated with higher all-cause mortality and greater health-care utilization. These findings highlight the role of social determinants in CTD-ILD outcomes and underscore the need for equity-focused strategies and interventions in this population. This abstract is funded by: NIH K08HL163406