Abstract P406: Atrial Fibrillation (AF) and Stroke Symptoms in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Background: AF-related thromboembolism increases risk of stroke. Stroke symptoms in the absence of a stroke diagnosis may represent “whispering strokes,” but their association with AF has not been well explored. Objective: To examine cross-sectionally the association between AF and self-reported stroke symptoms in the absence of a stroke diagnosis, and whether associations differ by anticoagulant use. Methods: We examined data from 27,072 REGARDS participants without a history of stroke or transient ischemic attack (TIA) at baseline. The presence, type, and cumulative number of self-reported stroke symptoms were compared between participants with and without self-reported history or ECG evidence of AF. Logistic regression models examined associations between AF and stroke symptoms, adjusting for sociodemographic, socioeconomic, stroke risk factors, and geographic characteristics. To investigate the possibility of stroke symptoms representing embolic stroke, results were stratified by anticoagulant or antiplatelet agent use. Results: The mean age of the sample was 64.4(±9.4), 55.3% were women, and 59.2% were black; 2,124 had evidence of AF. Twenty-nine percent of adults with AF and 17% of those without AF reported at least one stroke symptom. Compared to those without AF, the odds ratio (OR) of any stroke symptom was 2.21 (95% CI 1.88-2.58) among adults with AF not using an anticoagulant or antiplatelet agent and 1.93 (95% CI 1.62-2.30) for those on Aspirin or Plavix only ( Table 1 ). Associations were non-significant for those using Warfarin. Similar patterns were observed by each type and cumulative number of stroke symptoms. Conclusion: The association between AF and stroke symptoms suggests that some stroke symptoms in the absence of a stroke diagnosis may represent sub-clinical or “whispering strokes.” The attenuation of this association with Warfarin use but not antiplatelet agents supports the possibility that stroke symptoms in the absence of a stroke diagnosis represent undiagnosed embolic stroke.