Hospital Costs Associated With Atrial Fibrillation for Patients With Ischemic Stroke Aged 18–64 Years in the United States

Background and Purpose— Hospital costs associated with atrial fibrillation (AFib) among patients with stroke have not been well-studied, especially among people aged <65 years. We estimated the AFib-associated hospital costs in US patients aged 18 to 64 years. Methods— We identified hospital admissions with a primary diagnosis of ischemic stroke from the 2010 to 2012 MarketScan Commercial Claims and Encounters inpatient data sets, excluding those with capitated health insurance plans, aged 64 years, missing geographic region, hospital costs below the 1st or above 99th percentile, and having carotid intervention (n=40 082). We searched the data for AFib and analyzed the costs for nonrepeat and repeat stroke admissions separately. We estimated the AFib-associated costs using multivariate regression models controlling for age, sex, geographic region, and Charlson comorbidity index. Results— Of the 33 500 nonrepeat stroke admissions, 2407 (7.2%) had AFib. Admissions with AFib cost $4991 more than those without AFib ($23 770 versus $18 779). For the 6582 repeat stroke admissions, 397 (6.0%) had AFib. The costs were $3260 more for those with AFib than those without ($24 119 versus $20 929). After controlling for potential confounders, AFib-associated costs for nonrepeat stroke admissions were $4905, representing 20.6% of the total costs for the admissions. Both the hospital costs and the AFib-associated costs were associated with age, but not with sex. AFib-associated costs for repeat stroke admissions were not significantly higher than for non-AFib patients, except for those aged 55 to 64 years ($3537). Conclusions— AFib increased the hospital cost of ischemic stroke substantially. Further investigation on AFib-associated costs for repeat stroke admissions is needed.