Risk of Ischemic Stroke Recurrence in Patients with Atrial Fibrillation Detected after Ischemic Stroke Using Oral Anticoagulants: A Nationwide Cohort Study
Jin-Yi . Hsu, MD 1, 2 , Peter Pin-Sung Liu, 1 , Huei-Kai Huang, MD 2, 3, 4 , An-Bang Liu, PhD, MD 2, 5 , Ching-Hui Loh, PhD, MD 1, 2, 3 , Cheng-Yang Hsieh, PhD, MD 6, 7 ,
1 花蓮慈濟醫院 高齡健康中心
2 慈濟大學 醫學系
3 花蓮慈濟醫院 家庭醫學部
4 花蓮慈濟醫院 研究部
5 花蓮慈濟醫院 神經內科部
1 Center for Aging and Health, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
2 School of Medicine, Tzu Chi University, Hualien, Taiwan
3 Department of Family Medicine, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
4 Department of Medical Research, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
5 Department of Neurology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
6 Department of Neurology, Tainan Sin Lau Hospital, Tainan, Taiwan
7 School of Pharmacy, Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
Cheng-Yang Hsieh , PhD, MD
Department of Neurology, Tainan Sin Lau Hospital, Tainan, Taiwan
The risk of ischemic stroke seems to be different in patients with atrial fibrillation detected after ischemic stroke (AFDAS) than in those with a known history of atrial fibrillation (KAF). Physicians started using oral anticoagulants following ischemic stroke in patients with KAF due to the net benefit of their efficacy in stroke prevention against the risk of major bleeding. However, there is scant evidence regarding the association between the risk of further ischemic stroke and anticoagulant use in patients with AFDAS.
MATERIAL and METHOD:
We conducted a nationwide population-based cohort study using Taiwan’s National Health Insurance Research Database. Patients with first-ever ischemic stroke having an inpatient diagnosis of atrial fibrillation were enrolled, following which those with a history of atrial fibrillation were excluded. We classified the patients into the oral anticoagulant (OAC) and non-oral-anticoagulant (non-OAC) cohorts. The primary and secondary outcomes were the recurrence of ischemic stroke and the occurrence of intracranial hemorrhage, respectively. We estimated the risk of ischemic stroke with adjusted hazard ratios (aHR) and corresponding 95% confidence intervals (CIs) using the Fine and Gray competing risk regression model.
We enrolled 7,680 patients with AFDAS, including 4,823 and 2,857 patients in the OAC cohort and non-OACs cohort, respectively. After propensity score matching, each cohort comprised 2,602 patients with similar baseline characteristics, with a mean follow-up of 2.69 years. Compared to the non-OAC cohort, the OAC cohort had a lower risk of ischemic stroke recurrence (aHR: 0.81, 95% CI: 0.70–0.94) and a similar risk of intracranial hemorrhage (aHR: 1.39, 95% CI: 0.81–2.38).
Although previous studies revealed a lower risk of ischemic stroke recurrence in patients with AFDAS than those with KAF, our study indicated, as in the management of patients with KAF, that physicians should initiate oral anticoagulant therapy in patients with AFDAS.