Supplementary Material for: Sex discrepancies in the population incidence of stroke and hemorrhage related to atrial fibrillation or flutter

Introduction: Atrial fibrillation or flutter (AF) is a well-known risk factor for ischemic stroke. While female sex has been associated with higher stroke risk among AF patients, overall sex-specific real-world burdens of AF-related strokes and hemorrhages are unknown.

Methods: The 2016-2020 National Inpatient Sample was queried for hospitalizations, morbidity, and mortality due to AF-related ischemic strokes and bleeds. Patient demographic information, vascular risk factors, comorbidities, and stroke characteristics were extracted using ICD-10 codes. Overall incidences were calculated using total population estimates provided by the United States Census Bureau, and relative risk was calculated by comparing annual incidences between men and women.

Results: 2,420,870 ischemic stroke hospitalizations were identified; 542,635 (22.4%) were associated with AF. Overall, women had similar risk of hospitalization due to AF-related ischemic strokes compared to men; however, women had a higher risk of morbidity and mortality (RR 1.13 and 1.17, respectively; both p<0.001). In contrast, women had lower incidences of hospitalization, morbidity, and mortality due to AF-related bleeds (RR 0.82, 0.94, and 0.74, respectively; all p<0.001). Among patients with AF-related ischemic strokes, women had lower rates of anticoagulation use, higher rates of large vessel occlusion, and higher stroke severity (all p<0.001). These trends persisted among patients 80 years or older (all p<0.001).

Conclusion: Women in the United States have higher incidences of morbidity and mortality from AF-related ischemic strokes than men. Future studies should investigate strategies to reduce morbidity and mortality due to AF-related strokes in women.

引言：心房颤动（Atrial fibrillation or flutter, AF）是缺血性脑卒中的明确危险因素。尽管已有研究表明女性性别与房颤患者更高的脑卒中风险相关，但房颤相关脑卒中与出血事件的性别特异性真实世界疾病负担目前仍不明确。

方法：本研究检索了2016-2020年全国住院患者样本（National Inpatient Sample, NIS）中房颤相关缺血性脑卒中及出血事件的住院人次、发病与死亡数据。通过国际疾病分类第十版（ICD-10）编码提取患者人口学信息、血管危险因素、合并症及脑卒中特征。基于美国人口普查局（United States Census Bureau）提供的总人口估算值计算总发病率，并通过比较男女两性的年度发病率计算相对危险度（Relative Risk, RR）。

结果：本研究共纳入2420870例缺血性脑卒中住院病例，其中542635例（22.4%）与房颤相关。整体而言，女性房颤相关缺血性脑卒中的住院风险与男性相当；但女性的发病与死亡风险更高（相对危险度分别为1.13和1.17，均p<0.001）。与之相反，女性房颤相关出血事件的住院、发病及死亡发生率更低（相对危险度分别为0.82、0.94和0.74，均p<0.001）。在房颤相关缺血性脑卒中患者中，女性的抗凝治疗使用率更低、大血管闭塞发生率更高，且脑卒中严重程度更高（均p<0.001）。上述趋势在80岁及以上患者亚组中依然存在（均p<0.001）。

结论：美国女性房颤相关缺血性脑卒中的发病与死亡发生率高于男性。未来研究应探索降低女性房颤相关脑卒中发病与死亡风险的干预策略。