The relationship between COVID-19 and stroke and its risk factors, a Mendelian randomization analysis

It remains unclear about the association between stroke and Coronavirus disease 2019 (COVID-19). Therefore, a Mendelian randomization (MR) analysis was conducted to explore the relationship between them. In this study, the most recent large-scale genome-wide association studies (GWASs) were selected from the publicly available COVID-19 GWAS meta-analysis (Round 7) as the exposure. Data from a recent original stroke GWAS were used as the outcome for the experimental group, while the stroke GWAS data from the IEU GWAS database were used as the validation group. In addition, an MR analysis was conducted to explore the causal relationships of susceptibility, hospitalization, and severity of COVID-19 with stroke and its subtypes. In addition, the results of the experimental and validation groups were integrated to perform a meta-analysis. The MR analysis results corroborated that there was a positively causal relationship between the hospitalization (OR, 1.11; <i>p</i> = 0.015) (ORmeta, 1.11; <i>p</i> &lt; 0.001), and severity (OR, 1.06; <i>p</i> = 0.043) (ORmeta, 1.07; <i>p</i> = 0.002) of COVID-19 and cardioembolic stroke (CES). This result is supported by the validation group and sensitivity analysis. This study demonstrates for the first time that COVID-19 hospitalization and COVID-19 severity are risk factors for CES.