Abstract 4132: Atrial fibrillation in patients with cancer: Results from the nationwide readmission database
Authors: Heaton Joseph , Singh Sohrab , Singh Surbhi 
Published: June 2022

Introduction Cardiac diseases and cancer account for the majority of deaths in the United States. Prolonged survival in cancer patients have surfaced novel cardiovascular adverse outcomes. A rise in the number of arrhythmias, including atrial fibrillation, have been observed. The increased burden of atrial fibrillation in patients with non-metastatic cancer is not well explored. We aimed to discover the magnitude of the impact of cancer on readmission in patients with atrial fibrillation.

Methods We performed a retrospective cohort study utilizing the 2016 to 2019 Nationwide Readmission Database. International Classification of Diseases, Tenth Revision (ICD-10) codes were used to identify diagnoses and procedures. Patients were included in the study if they were at least 18 years of age with a non-elective admission for atrial fibrillation between January and November. Atrial Fibrillation was defined as admissions with the primary diagnosis code I48.0, I48.11, I48.19, I48.20, I48.21, or I48.91. Non-metastatic cancer was identified using the Elixhauser Comorbidity Software. We assessed the effect of non-metastatic cancer on 30-day atrial fibrillation readmission rate and analyzed temporal trends.

Results Baseline characteristics for 1,272,156 index admissions were identified. The mean age was 71 +/- 13 years, and 52.2% were female. Readmissions occurred in 11.7% of total index admissions; 11.4% of non-cancer patients versus 16.8% with cancer (p&lt;0.001). Multivariate regression analysis showed that patients with cancer were 1.47 times more likely to be readmitted (95% CI, 1.41 - 1.52; p&lt;0.001). Though, patients with cancer were 51.8% less likely to be readmitted after a palliative care consultation (p &lt;0.001). Patients were most likely to be readmitted due to episodes of atrial fibrillation, hypertensive heart failure, and sepsis. In-hospital mortality was higher in the cancer group (7.2% vs 4.2%, p &lt;0.001), with multivariate Cox regression indicating a hazard ratio of 1.41 in the cancer group. Patients with cancer, on average, also had higher a length of stay (4.3 days vs. 3.5 days, p &lt;0.001), total cost ($17,780, p &lt;0.001), and were more likely to be discharged to a skilled nursing facility (13.8% vs 11.0%). There was no significant difference in the likelihood of pacemaker or CRT placement. Finally, patients with cancer were 3.2% more likely to die during a readmission (p &lt;0.001)

Conclusions Atrial fibrillation and a concomitant non-metastatic cancer diagnosis tend to portray poor outcomes, including higher readmission, length of stay, in-hospital mortality, and healthcare cost, compared to patients without a non-metastatic cancer diagnosis. Cardio-oncology is a developing novel multidisciplinary specialty aimed at understanding and treating the cardiac burden in cancer patients. Further investigation is needed to discern the interplay of mechanisms between cancer and arrhythmias

Citation Format: Joseph Heaton, Sohrab Singh, Surbhi Singh. Atrial fibrillation in patients with cancer: Results from the nationwide readmission database [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4132.