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IMPORTANCEThe CHA 2 DS 2 -VASc score (calculated as congestive heart failure, hypertension, age 75 years and older, diabetes, stroke or TIA, vascular disease, age 65 to 74 years, and sex category) is the standard for assessing risk of stroke and systemic embolism and includes age and thromboembolic history. To our knowledge, no studies have comprehensively evaluated safety and effectiveness outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants according to independent, categorical risk strata. OBJECTIVETo evaluate the incidence of key adverse outcomes among patients with nonvalvular atrial fibrillation receiving oral anticoagulants by CHA 2 DS 2 -VASc risk score range, thromboembolic event history, and age group. DESIGN, SETTING, AND PARTICIPANTSThis cohort study was a retrospective claims data analysis using combined data sets from 5 large health claims databases. Eligible participants were adult patients with nonvalvular atrial fibrillation who initiated oral anticoagulants. Data were analyzed between January 2012 and June 2019. EXPOSURE Initiation of oral anticoagulants. MAIN OUTCOMES AND MEASURESWe observed clinical outcomes (including stroke or systemic embolism, major bleeding, and a composite outcome) on treatment through study end, censoring for discontinuation of oral anticoagulants, death, and insurance disenrollment. The population was stratified by CHA 2 DS 2 -VASc risk score; history of stroke, systemic embolism, or transient ischemic attack; and age groups. We calculated time to event, incidence rates, and cumulative incidence for outcomes. RESULTSWe identified 1 141 097 patients with nonvalvular atrial fibrillation; the mean (SD) age was 75.0 (10.5) years, 608 127 patients (53.3%) were men, and over 1 million were placed in the 2 highest risk categories (high risk 1, 327 766 participants; high risk 2, 688 449 participants). Deyo-Charlson Comorbidity Index scores ranged progressively alongside CHA 2 DS 2 -VASc risk score strata (mean [SD] scores: low risk, 0.4 [1.0]; high risk 2, 4.1 [2.9]). The crude incidence of stroke and systemic embolism generally progressed alongside risk score strata (low risk, 0.25 events per 100 person-years [95% CI, 0.18-0.34 events]; high risk 2, 3.43 events per 100 person-years [95% CI, 3.06-4.20 events]); patients at the second-highest risk strata with thromboembolic event history had higher stroke incidence vs patients at the highest risk score strata without event history (2.06 events per 100 person-years [95% CI, 2.00-3.12 events] vs 1.18 events per 100 person-years [95% CI, 1.14-1.30 events]). Major bleeding and composite incidence also increased progressively alongside risk score strata (major bleeding: low risk, 0.68 events per 100 person-years [95% CI, 0.56-0.82 events]; high risk 2, 6.29 events per 100 person-years [95% CI, 6.21-6.62 events]; composite incidence: 1.22 (continued) Key Points Question What are the relative safety and effectiveness outcomes among patients with nonvalvular atrial fibrillation receiving anticoa...

Introduction: The CHA 2 DS 2 -VASc score is an established tool to determine the risk of stroke among atrial fibrillation (AF) patients. The goal of this retrospective claims analysis is to evaluate the incidence of stroke/systemic embolism (SE) and major bleeding (MB) events among patients with non-valvular AF (NVAF) who initiated an oral anticoagulant (OAC; apixaban, dabigatran, edoxaban, rivaroxaban, or warfarin) relative to their CHA 2 DS 2 -VASc score. Methods: Adult NVAF patients who initiated OACs were identified from 01JAN2013-31MAR2019 using data from five insurance claims databases. Patients were required to have 12 months continuous enrollment prior to index (OAC claim date) and were followed to the earliest of OAC discontinuation, death, disenrollment, or study end. Results were stratified by CHA 2 DS 2 -VASc score on index: low (0 for males and 1 for females), moderate (1 for males and 2 for females), high risk 1 (2-3 for males and 3 for females) and high risk 2 (≥4 for males and females). The incidence rate and cumulative incidence were reported for stroke/SE and MB, defined by hospitalization with a primary diagnosis of the respective outcomes. Results: A total of 1,141,097 NVAF patients were identified including 29,298 low risk, 95,584 moderate risk, 327,766 high risk 1 and 688,449 high risk 2 patients. The median follow-up time for all patients was 160 days. The incidence of stroke/SE and MB was 1.3 and 4.1 per 100 person years, respectively. Cumulative incidence for stoke/SE and MB increased across risk groups (Figure). Significant differences were seen for both stroke/SE and MB, when comparing the high risk 1 or high risk 2 group to the low-risk reference group. Conclusions: Assessing stroke/SE and MB events by CHA 2 DS 2 -VASc risk category demonstrates the differences in the rate of events according to the risk groups and provides insight for anticoagulated NVAF patients with clinical risk factors.

INTRODUCTION: Atrial fibrillation (AF) is one of the most common cardiac arrhythmias in the general population and is considered disqualifying aeromedically. This study is a unique examination of significant outcomes in aviators with previous history of both AF and stroke.METHODS: Pilots examined by the FAA between 2002 and 2012 who had had AF at some point during his or her medical history were reviewed, and those with an initial stroke or transient ischemic attack (TIA) during that time period were included in this study. All records were individually reviewed to determine stroke and AF history, medical certification history, and recurrent events. Variables collected included medical and behavior history, stroke type, gender, BMI, medication use, and any cardiovascular or neurological outcomes of interest. Major recurrent events included stroke, TIA, cerebrovascular accident, death, or other major events. These factors were used to calculate CHA2DS2-VASc scores.RESULTS: Of the 141 pilots selected for the study, 17.7% experienced a recurrent event. At 6 mo, the recurrent event rate was 5.0%; at 1 yr, 5.8%; at 3 yr 6.9%; and at 5 yr the recurrent event rate was 17.3%. No statistical difference between CHA2DS2-VASc scores was found as it pertained to number of recurrent events.DISCUSSION: We found no significant factors predicting risk of recurrent event and lower recurrence rates in pilots than the general population. This suggests CHA2DS2-VASc scores are not appropriate risk stratification tools in an aviation population and more research is necessary to determine risk of recurrent events in aviators with atrial fibrillation.Tedford J, Skaggs V, Norris A, Sahiar F, Mathers C. Recurrent stroke risk in pilots with atrial fibrillation. Aerosp Med Hum Perform. 2020; 91(4):352–357.