ImportancePatients with atrial fibrillation (AF) can have an ischemic stroke (IS) despite oral anticoagulant (OAC) treatment. Knowledge regarding the association between OAC discontinuation and the subsequent risk of recurrent IS in patients with AF is limited.ObjectivesTo determine the risk of recurrent IS in patients with AF receiving OAC and to evaluate the association between OAC discontinuation and the risk of recurrent IS.Design, Setting, and ParticipantsThis is a nationwide cohort study of patients aged 50 years or older in Denmark who had AF and an IS (entry IS) and were initiating or restarting subsequent OAC treatment after being discharged between January 2014 and December 2021. Patients were followed up for recurrent IS until June 2022. Within this study cohort, a nested case-control analysis was performed in which patients with recurrent IS were matched to patients receiving OAC who had not yet experienced a stroke. Data were analyzed from May 25, 2023, to April 18, 2024.ExposureUse of OAC at the time of recurrent IS or the equivalent date in matched controls based on redeemed prescriptions.Main Outcomes and MeasuresThe primary outcome was recurrent IS. Crude and adjusted cumulative incidences of recurrent IS and all-cause mortality were calculated in cohort analyses, and adjusted odds ratios (aORs) were determined for recurrent IS associated with OAC discontinuation in nested case-control analyses.ResultsThe study cohort included 8119 patients (4392 [54.1%] male; mean [SD] age, 78.4 [9.6] years; median (IQR) CHA2DS2-VASc score, 4.0 [3.0-5.0]). Over a mean (SD) follow-up of 2.9 (2.2) years, 663 patients had a recurrent IS, of whom 533 (80.4%) were receiving OAC at the time of their recurrent IS. The crude cumulative incidence of recurrent IS at 1 year was 4.3% (95% CI, 5.9%-7.1%), and the crude cumulative incidence of all-cause mortality was 15.4% (95% CI, 14.7%-16.2%). Adjusted analysis showed similar results. Patients who discontinued OACs had a higher risk of recurrent IS (89 cases [13.4%], 180 controls [6.8%]; aOR, 2.13; 95% CI, 1.57-2.89) compared with patients still receiving OAC.Conclusions and RelevanceThe risks of recurrent IS and mortality were high in patients with AF despite secondary prevention with OAC, and OAC discontinuation doubled the risk of recurrent IS compared with patients who continued OAC. This finding highlights the importance of OAC continuation and the need for improved secondary stroke prevention in patients with AF.

中文翻译：

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接受口服抗凝剂的心房颤动患者复发性缺血性中风


重要性尽管接受口服抗凝剂 (OAC) 治疗，心房颤动 (AF) 患者仍可能发生缺血性中风 (IS)。关于 OAC 停用与 AF 患者 IS 复发风险之间关系的知识有限。目的确定接受 OAC 治疗的 AF 患者 IS 复发风险，并评估 OAC 停用与 IS 复发风险之间的关联。设计、环境和参与者这是一项全国性队列研究，对象为丹麦 50 岁或以上的患者，这些患者患有 AF 和 IS（进入 IS），并在 2014 年 1 月至 2021 年 12 月期间出院后开始或重新开始后续 OAC 治疗。对患者进行了随访直到 2022 年 6 月，复发性 IS 才会出现复发。在该研究队列中，进行了一项巢式病例对照分析，其中复发性 IS 患者与接受 OAC 治疗且尚未经历中风的患者进行匹配。数据分析时间为2023年5月25日至2024年4月18日。暴露在复发性IS时或基于兑换处方的匹配对照中的同等日期使用OAC。主要结果和措施主要结果是复发性IS。在队列分析中计算了复发性 IS 和全因死亡率的粗略和调整累积发生率，并在巢式病例对照分析中确定了与 OAC 停药相关的复发性 IS 的调整优势比 (aOR)。 结果 研究队列包括 8119 名患者（4392 名患者） [54.1%] 男性；平均 [SD] 年龄，78.4 [9.6] 岁；中位 (IQR) CHA 2 DS 2 -VASc 分数，4.0 [3.0-5.0]）。在平均 (SD) 2.9 (2.2) 年的随访中，663 名患者复发了 IS，其中 533 名 (80.4%) 在复发 IS 时正在接受 OAC。 1 年时复发性 IS 的粗累积发生率为 4.3%（95% CI，5.9%-7.1%），全因死亡率的粗累积发生率为 15.4%（95% CI，14.7%-16.2%）。调整后的分析显示出类似的结果。与仍在接受 OAC 的患者相比，停止 OAC 的患者复发 IS 的风险更高（89 例 [13.4%]，180 名对照 [6.8%]；aOR，2.13；95% CI，1.57-2.89）。结论和相关性尽管使用 OAC 进行二级预防，AF 患者的复发性 IS 和死亡率仍然很高，并且与继续使用 OAC 的患者相比，停用 OAC 使复发性 IS 的风险增加了一倍。这一发现强调了继续进行 OAC 的重要性以及改进 AF 患者中风二级预防的必要性。