Supplementary Material for: Risk Stratification for Ischemic Cerebrovascular Events and Mortality among Intracerebral Hemorrhage Patients with and without Atrial Fibrillation: A Nationwide Cohort Study

Background: Intracerebral hemorrhage is a devastating clinical event, and secondary prevention is pivotal to avoid further cerebral complications, but no clear guidance exist for selecting high-risk patients. The CHA₂DS₂-VASc score is a widespread tool to assess the risk of stroke among patients with atrial fibrillation (AF). Objectives: We investigated the ability of the CHA₂DS₂-VASc score for estimating cerebrovascular ischemic events in patients with recent intracerebral hemorrhage with or without comorbid AF. Methods: Patients with a diagnosis of intracerebral hemorrhage between 2003 and 2018 were considered for inclusion. Four registries were linked to obtain individual-level information, and included patients were followed for the occurrence of cerebrovascular ischemic events and all-cause mortality. We report absolute risks at 5 years stratified by baseline CHA₂DS₂-VASc score and AF prevalence. Results: The study included 12,245 patients (46.4% females) of whom 19% had prevalent AF. Patients without AF were younger (mean age: 70 vs. 78 years) and had a lower CHA₂DS₂-VASc score (2.5 vs. 3.6). The overall 5-year risk of cerebrovascular ischemic events was 5.2% (95% CI 4.7–5.6) for patients without AF and 7.3% (95% CI 6.0–8.5) for AF patients; all-cause mortality was higher than 30 and 50% in patients without or with AF, respectively. The predictive performance of the CHA₂DS₂-VASc score was poor with c-statistics around 0.56 regardless of AF status. Among patients without AF, a score ≥6 was associated with a 7.0% risk of cerebrovascular ischemic events. In patients with AF, the associated risk was lowest for patients with a CHA₂DS₂-VASc score of 1 (4.1%) and highest among those with a score of 5 (11.9%). Conclusion: In this nationwide cohort of intracerebral hemorrhage patients with or without AF, the risk of cerebrovascular ischemic events and mortality was substantial. The CHA₂DS₂-VASc score may be used for the estimation of stroke risk in patients sustaining an intracerebral hemorrhage, although its discriminative performance was poor.