Contemporary burden of atrial fibrillation in mechanical thrombectomy stroke patients in the United States

BackgroundHow the prevalence of atrial fibrillation (AF) differs between various demographic subgroups of acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT) in the United States (US) is unknown. Data on whether AF prevalence in MT admissions changed over the last decade are sparse. MethodsWe conducted a serial cross-sectional study using all primary AIS discharges in the 2010-2020 National Inpatient Sample. Discharges with MT codes were identified (n=155,277) and the proportion with AF in various age, sex and racial subgroups were computed. We used multivariable-adjusted negative binomial regression to compare AF prevalence between demographic subgroups and Joinpoint regression to evaluate trends over time. Multivariable-adjusted generalized linear models were used to evaluate the association of AF with in-hospital outcomes. ResultsAcross the study period, 45.0% of AIS discharges with MT had AF but marked disparity existed by age, sex and race. After multivariable adjustment, AF prevalence was 4% higher in women vs. men (prevalence rate ratio [PRR] 1.04, 95%CI 1.01-1.07), was lower in Black vs White (PRR 0.80, 95%CI 0.77-0.84) but higher in Asian compared to White discharges (PRR 1.11, 95%CI 1.05-1.18). Prevalence increased with age (PRR for [≥]80 years vs 18-39 years: 5.23, 95%CI 4.28-6.39). Following joinpoint regression, prevalence increased by 3.2% (95%CI 1.3 to 5.2%) annually across the period 2010-2015 but declined by -2.2% (95%CI -2.9% to -1.4%) from 2015-2020. AF was associated with 27% lower odds of in-hospital mortality (Odds ratio 0.72, 95%CI 0.62-0.84) and 31% greater odds of routine home discharge (Odds ratio, 95%CI 1.17 to 1.47) compared to no AF. ConclusionAF prevalence in MT patients in the US is approximately twice that of the general AIS population but marked disparity exists by age, sex and race. AF Prevalence in MT increased from 2010-2015 but declined in the period 2015-2020. Clinical PerspectiveO_ST_ABSWhat is new?C_ST_ABSO_LIApproximately 45% of mechanical thrombectomy acute ischemic stroke hospitalizations have comorbid atrial fibrillation (AF) and this proportion increases with age with 70% of patients >=80 years having AF. C_LIO_LIIn contrast to all AIS patients, in the subset of AF patients undergoing MT, AF is associated with reduced in-hospital mortality and better odds of routine home discharge. C_LI What are the clinical implications?O_LIGiven the post-stroke CHA2DS2-VASc score of at least 2, almost half of all MT patients in the US may be potential candidates for therapeutic anticoagulation. C_LI