Supplementary Material for: Prevalence and characteristics of known versus newly detected atrial fibrillation in ischemic stroke: a population-based study

Background: Atrial fibrillation (AF) is frequently diagnosed during the acute stage of ischemic (IS), and it may reflect undiagnosed AF before stroke, thus representing a missed opportunity for stroke prevention. This population-based study aimed to assess the prevalence of known AF (KAF) and AF diagnosed early after IS (AFDAS), and to compare clinical and brain/arterial imaging characteristics between patients.
Methods: Among patients with acute IS recorded in the population-based Dijon Stroke Registry, France (2013-2020), we identified those with KAF or AFDAS. AFDAS was considered when AF was diagnosed during the initial work-up based on electrocardiograms, in-hospital continuous electrocardiographic and/or Holter monitoring. Clinical and imaging characteristics on brain CT-scan or angio-CT-scan when available including old parenchymal lesions, arterial territory of the index IS, and aortic arch, cervical and intracranial arteries atheroma were compared between groups (KAF versus AFDAS). Regression logistic models were used to assess factors associated with AFDAS (compared to KAF).
Results: Among 1756 IS patients, 550 (31.3%) had AF (mean age: 83.6 ±10.3 years old, 60.5% women), of whom 367 (66.7%) presented with KAF and 183 (33.3%) had AFDAS. In multivariable model, hypertension (OR=0.37; 95% CI: 0.21-0.64, p<0.001), chronic heart failure (OR=0.34; 95% CI: 0.18-0.67, p=0.002), previous stroke (OR=0.42; 95% CI: 0.26-0.67, p<0.001), and preexisting dementia (OR=0.36; 95% CI: 0.21-0.63, p<0.001), were inversely associated with AFDAS, whereas NIHSS score was associated with AFDAS (OR=1.02; 95% CI: 1.00-1.05, p=0.012).
Conclusions: Our findings indicate a more advanced stage of the atrial cardiomyopathy in KAF as compared with AFDAS patients, and may thus contribute to the fact that in these latter patients AF had not been diagnosed prior to stroke. This group of patients undeniably represents a missed opportunity for stroke prevention.

研究背景：缺血性卒中（ischemic stroke, IS）急性期常可诊断出心房颤动（atrial fibrillation, AF），此类情况可能提示卒中发生前即存在未被确诊的心房颤动，因而错失了卒中预防的时机。本项基于人群的研究旨在评估已知心房颤动（known AF, KAF）的患病率，以及缺血性卒中后早期诊断的心房颤动（AF diagnosed early after IS, AFDAS）的患病率，并对比两组患者的临床特征与脑/动脉影像学特征。

方法：本研究纳入法国第戎卒中登记库（Dijon Stroke Registry）2013-2020年收录的急性缺血性卒中患者，从中筛选出合并已知心房颤动或卒中后早期诊断心房颤动的受试者。卒中后早期诊断心房颤动的定义为：在初始临床评估期间，通过心电图、住院持续心电监测及/或动态心电图（Holter）确诊的心房颤动。对比两组（已知心房颤动组与卒中后早期诊断心房颤动组）的临床特征，以及可行时的颅脑CT扫描或血管CT扫描特征，包括脑实质陈旧性病变、责任缺血性卒中的动脉供血区域，以及主动脉弓、颈动脉与颅内动脉粥样硬化情况。采用logistic回归模型分析与卒中后早期诊断心房颤动（相较于已知心房颤动）相关的影响因素。

结果：1756例缺血性卒中患者中，550例（31.3%）合并心房颤动，患者平均年龄为83.6±10.3岁，女性占比60.5%；其中367例（66.7%）为已知心房颤动，183例（33.3%）为卒中后早期诊断心房颤动。多因素回归分析显示，高血压（优势比OR=0.37；95%置信区间CI: 0.21-0.64，P<0.001）、慢性心力衰竭（OR=0.34；95%CI: 0.18-0.67，P=0.002）、既往卒中史（OR=0.42；95%CI: 0.26-0.67，P<0.001）以及既往痴呆（OR=0.36；95%CI: 0.21-0.63，P<0.001）与卒中后早期诊断心房颤动呈负相关；而美国国立卫生研究院卒中量表（NIHSS）评分则与卒中后早期诊断心房颤动呈正相关（OR=1.02；95%CI: 1.00-1.05，P=0.012）。

结论：本研究结果表明，与卒中后早期诊断心房颤动患者相比，已知心房颤动患者的心房心肌病进展程度更高，这也解释了为何此类卒中后早期诊断心房颤动患者在卒中发生前未被确诊心房颤动。该类患者群体无疑代表了卒中预防中被错失的机会。