Introduction: Oral anticoagulants (OAC) prevent stroke in patients with atrial fibrillation (AF) yet many are not prescribed OAC. Exploring barriers to OAC among AF patients at high stroke risk might identify opportunities to intervene.
Hypothesis: Old age, fall risk, and comorbidity will be strong barriers to use of OAC even among survivors of acute ischemic stroke (IS).
Methods: Inpatient and 1-year follow-up of patients sustaining an acute IS within the ATRIA and ATRIA-CVRN community-based AF cohorts (1996-2009; n=46,806). MD chart reviewers recorded use of OAC (warfarin) at discharge (96% complete), reasons for non-use, and modified Rankin disability score at discharge. Logistic regression identified patient features associated with non-use of OAC. Follow-up recorded 1-year mortality and recurrent IS.
Results: Of 1,405 AF patients discharged alive after IS, 44% (619) were not prescribed OAC despite a median CHA2DS2-VASc score of 5. The most frequent (non-mutually exclusive) reasons for non-use of OAC included risk of falls (26.7%), poor prognosis (19.3%), bleeding history (17.1%), patient/family refusal (14.9%), older age (11.0%) and dementia (9.4%). Logistic regression identified older age (OR 9.0, 95% CI 5.0-16.0 for age ≥85 vs. <65 yrs) and increased disability on discharge (OR 12.6, 95% CI 5.8-27.2 for severe deficit vs. no deficit) as the strongest independent clinical features associated with non-use of OAC at discharge. One-year mortality for those not receiving OAC at discharge was 43%--far higher than risk of recurrent IS (7.7%).
Conclusions: Despite very high stroke risk, >40% of AF/IS patients were not discharged on OAC. The dominant reasons for non-use of OAC were fall risk, poor prognosis, bleeding history, patient refusal, older age, and dementia. The high 1-year mortality rate confirmed these patients’ high comorbidity burden. Effective mitigation of fall risk or the improved safety profiles of newer anticoagulants might increase use of OACs. However, despite the substantial stroke protection benefit from OACs, understandable obstacles to OAC remain for many older and complex AF patients.