Thromboembolic disease in breast cancer: Analysis of risk factors and outcomes from the 2022 National Inpatient Sample and Readmission database.

e23339 Background: Thromboembolic disease significantly impacts breast cancer patients' outcomes and healthcare resource utilization. We analyzed the 2022 National Inpatient Sample to evaluate the prevalence, risk factors, and outcomes of venous thromboembolism (VTE) in hospitalized breast cancer patients. Methods: Study design: Retrospective analysis of the 2022 National Inpatient Sample database, representing 97% of US hospital discharges. Primary endpoints: VTE occurrence, length of stay, total charges, and in-hospital mortality. Breast cancer and VTE events were identified using ICD-10 codes (C50.xx and I26.xx/I80.xx/I82.xx/I74.xx respectively). Propensity score matching (1:1) was implemented to account for confounding factors including demographics, comorbidities, and admission characteristics. Multivariable logistic regression assessed independent predictors of VTE. Missing data were handled through complete case analysis. Potential confounders included age, race, comorbidity score, admission type, and hospital characteristics. Results: Of 6,578,372 hospitalizations, 34,194 breast cancer cases were identified (0.52%), with VTE occurring in 1,595 cases (4.66%). In the propensity-matched cohort (n = 2,777), VTE was independently associated with increased length of stay (mean difference: 3.1 days, 95% CI 2.8-3.4, p < 0.001), higher total charges (mean difference: $36,222, 95% CI $31,245-$41,199, p < 0.001), and increased in-hospital mortality (OR 1.71, 95% CI 1.22-2.41, p = 0.002). Metastatic disease (OR 2.79, 95% CI 1.88-4.15, p < 0.001), solid tumor status (OR 2.17, 95% CI 1.46-3.23, p < 0.001), and teaching hospital status (OR 1.57, 95% CI 1.19-2.08, p = 0.001) were significant predictors of VTE. Elective admissions showed a protective effect (OR 0.38, 95% CI 0.31-0.48, p < 0.001). Conclusions: This large-scale analysis demonstrates that VTE in breast cancer patients significantly impacts clinical outcomes and healthcare utilization. Risk stratification based on identified predictors, particularly metastatic disease status and admission type, may help optimize preventive strategies. Independent predictors of VTE in breast cancer patients (N=2,777). Risk Factor Odds Ratio (95% CI) P-value Healthcare Costs Metastatic Disease 2.79 (1.88-4.15) <0.001 +29.3% Solid Tumor 2.17 (1.46-3.23) <0.001 +36.6% Teaching Hospital 1.57 (1.19-2.08) 0.001 +31.8% Elective Admission 0.38 (0.31-0.48) <0.001 +38.4% Analysis based on propensity-matched cohorts. CI = Confidence Interval. Model adjusted for age, race, comorbidity score, and hospital characteristics.