Hospital outcomes in patients with neuroendocrine tumors and atrial-fibrillation/flutter.

e23066 Background: Neuroendocrine Tumors (NETs) are rare, aggressive malignancies that often metastasize widely and can cause significant complications, including cardiac involvement. Atrial fibrillation/flutter (AF) is a common cardiac arrhythmia that may arise in patients with NETs due to hormone-mediated valvular dysfunction, systemic inflammation, or hemodynamic changes. Despite the growing prevalence of NETs and their associated cardiovascular complications, limited data exists on the clinical impact of AF in this population. Understanding how AF affects hospital outcomes is critical to inform treatment strategies and improve prognosis. This study evaluates in-hospital outcomes, including mortality, length of stay, and healthcare costs, in patients with NETs and AF. Methods: We conducted a retrospective cohort study using the 2019–2021 National Inpatient Sample (NIS) database. Patients with neuroendocrine tumors and atrial fibrillation/flutter were identified using ICD-10-CM codes. Primary and secondary outcomes included in-hospital mortality, length of stay, hospital charges, stroke, and heart failure. Statistical analyses included t-tests, chi-square tests, and multivariable logistic regression to compare outcomes. Results: This study analyzed data from 110,445 patients with neuroendocrine tumors, of whom 16,510 (14.94%) had AF. Patients with AF were significantly older (mean age 72.7 years) compared to those without AF (mean age 63.2 years) (p < 0.001). The prevalence of AF was higher in males (58.21%) than females (41.79%) (p < 0.001) and was more common in White patients (81.89%) compared to Black (10.09%) and Hispanic (4.20%) patients (p < 0.001). AF was also associated with lower median household income (p = 0.02), residence in the South region (p = 0.02), treatment at larger hospitals (p = 0.005), and urban teaching hospital settings (p < 0.001). Patients with AF were more likely to have Medicare (76.22%) and less likely to have private insurance (16.39%) (p < 0.001). Critically, AF was associated with a significantly higher mortality rate (9.87% vs. 5.4%; adjusted OR 1.74, 95% CI 1.51-2.01; p < 0.001), a longer length of stay (7.6 vs. 6.4 days; p < 0.001), and higher total cost of hospitalization (105,868 vs. 88,750; p < 0.001). Conclusions: Our findings highlight the substantial impact of atrial fibrillation/flutter on patients with neuroendocrine tumors. AF in this population is associated with significantly worse in-hospital outcomes, including higher mortality, prolonged hospital stays, and increased healthcare costs. These findings underscore the importance of early recognition and aggressive management of AF in patients with NETs.