Supplementary Material for: A Systematic Review and Meta-Analysis Comparing Mortality Between In-Hospital vs Community-Onset Acute Ischemic Stroke

Background and Purpose: Patients who experience in-hospital strokes may suffer from delays in stroke recognition, delays to acute treatment and management. We aimed to assess evidence for the difference in mortality between patients with in-hospital stroke and those with community-onset stroke.

Methods: We searched MEDLINE, EMBASE and SCOPUS (from inception to October 8, 2024) to identify studies comparing mortality outcomes for in-hospital and community-onset stroke patients. We collected data on study characteristics, summarized the quality of evidence, evaluated risk of bias of studies using the Newcastle Ottawa Scale, and investigated clinical sources of heterogeneity. We performed a random-effects meta-analysis to estimate the pooled odds of mortality of in-hospital stroke vs community-onset stroke patients.

Results: Forty-one studies, collectively with 3,038,211 patients and, of whom, 3% experienced in-hospital stroke were included in the review. In-hospital stroke patients had an approximate 2.3-fold higher odds of in-hospital mortality (pooled OR 2.27; 95% CI 1.80 – 2.86; 32 patient cohorts) and 1.9-fold higher odds of 3-month mortality (pooled OR 1.87; 95% CI 1.43–2.45; 14 patient cohorts) compared to community-onset stroke patients. Meta-analyses stratified by acute treatment received and study characteristics revealed consistently higher odds of death among in-hospital stroke patients compared to community-onset stroke patients. Acute treatment received, study setting, geographic region and components of study quality were significant sources of heterogeneity. Most concerns in study quality were due to potential risks of confounding.

Conclusion: There was a consistently higher odds of in-hospital and 3-month mortality among in-hospital acute ischemic stroke patients compared to their community-onset counterparts, highlighting the need for targeted interventions to reduce this disparity.