Abstract 19254: Sex Differences for Patients With New-onset Atrial Fibrillation During Hospitalization

Introduction: New-onset atrial fibrillation (AF) during hospitalization has been associated with worse outcomes. However, there is little information on the risk factors associated with the development of new-onset AF. We assessed whether there are sex differences in the incidence and mortality of hospitalized patients with new-onset AF. Methods: We utilized the National Inpatient Sample to analyze new-onset AF in a sample of inpatient hospitalizations from 2001 to 2011. New-onset AF was defined by an ICD-9 discharge code of 427.3 not present on admission. We performed multivariate logistic regression for incidence and all-cause in-hospital mortality of female versus male sex for new-onset AF, adjusting for comorbid conditions and other demographic factors (described in Table). We separated our analyses by principal diagnosis of guideline-defined acute conditions associated with new-onset AF: noncardiac surgery, cardiac surgery, myocardial infarction, sepsis, pulmonary embolism, myocarditis, and thyrotoxicosis. Results: A total of 38,403,360 cases of new-onset AF were identified. The majority of new-onset AF cases (85%) were associated with admissions for noncardiac surgery (Table). Female sex was associated with decreased incidence of new-onset AF across all acute conditions (p <0.05). Female sex was also associated with decreased mortality of new-onset AF patients admitted for noncardiac surgery and thyrotoxicosis but increased mortality for new-onset AF patients admitted for cardiac surgery, sepsis, myocardial infarction, and pulmonary embolism (p <0.05). Conclusion: Female sex is associated with a decreased incidence for new-onset AF; however, it is also a risk factor for in-hospital mortality for a majority of acute conditions linked to new-onset AF. Further quality improvement measures should elucidate and target the mechanisms for this discrepancy.