Incidence of Atrial Fibrillation and Related Outcomes among Hospitalized Patients with Systemic Lupus Erythematosus: Analysis of United States Nationwide Inpatient Sample Database 2016-2019.

Background: While patients with systemic lupus erythematosus (SLE) are known to have an increased risk of developing atrial fibrillation (AF), there is a scarcity of national population-based studies that evaluate the impact of AF on SLE. Methods: In this study, we use the 2016 to 2019 National Inpatient Sample (NIS) to determine the impact of AF on inpatient outcomes among adults hospitalized with systemic lupus erythematosus (SLE). Among a total of 41,004 SLE hospitalizations, 1495 (3.65%) patients had a concurrent diagnosis of AF. The baseline hospital and patient characteristics for both cohorts (SLE with AF and SLE without AF) were compared using the chi-square test and Student's t-test while univariate and multivariate regression analysis were used to calculate the unadjusted and adjusted odds ratios (aOR) for in-hospital outcomes for both cohorts. Results: Our data revealed that among SLE patients, AF was associated with higher in-hospital mortality (aOR 2.07), length of stay (9.03 days), and hospital costs (USD 100,190.50) along with increased incidence of non-ST-elevation myocardial infarction (NSTEMI) (aOR 2.79), pericardial effusion (aOR 2.38), cardiac tamponade (aOR 3.33), and cardiogenic shock (aOR 8.19). Conclusion: Our findings suggest that patients hospitalized with SLE and underlying AF may be at risk for poor clinical outcomes.