Ischemic stroke associated with COVID-19: a systematic review and meta-analysis

BACKGROUND: Coronavirus disease 2019 (COVID-19), a contagious infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread across the world. Apart from respiratory complications, an increasing number of patients with ischemic stroke have been reporting. OBJECTIVE: This systematic review and meta-analysis aims to explore the characteristics of ischemic stroke after SARS-CoV-2 infection, and provides valuable reference materials for subsequent clinical treatment. MATERIALS AND METHODS: PubMed, Web of Science, and Ovid-Embase databases were searched up to 24th March 2021. We utilized the search strategy of medical subject headings combined with entry terms to search all related literatures. All studies identified with the electronic and manual searches were listed by citation, title, authors, and abstract. Only studies involving patients with COVID-19-related stroke were eligible. The references of included studies were also manually screened. RESULTS: The meta-analysis was conducted following the PRISMA and MOOSE reporting guidelines. Bias risk was assessed using the Newcastle–Ottawa Scale (NOS). Ten articles, including 26,691 participants and 280 patients with ischemic stroke and COVID-19, were selected. The pooled prevalence of ischemic stroke in COVID-19 was 2% (95% CI 1–2%; p < 0.01). The pooled proportions of hypertension, hyperlipidemia and diabetes in COVID-19-related ischemic stroke was 66% (95% CI 51–81%; p < 0.01), 48% (95% CI 19–76%; p < 0.01) and 40% (95% CI 29–51%; p < 0.01), respectively. Notably, the pooled proportions of female was 36% (95% CI 21–50%; p < 0.01) in patients with COVID-19 and stroke. In addition, in TOAST classification, cryptogenic stroke subtype was associated with a high trend, and its pooled proportion was 35% (95% CI 12–59%; p < 0.01). CONCLUSION: Ischemic stroke caused by COVID-19 has its own unique clinical features. Although common high-risk factors can also be observed, its importance may have changed. The major inflammatory storm of COVID-19 is more likely to occur in male patients. The increase in the proportion of cryptogenic stroke has also made stroke related to COVID-19 complicated. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00415-021-10837-7.