Causality between ischemic stroke and glioblastoma: Bidirectional Mendelian randomization analysis

With the global increase in glioblastoma (GBM) and ischemic stroke (IS) cases, the association between IS and GBM remains a topic of debate. In this study, we examined the causal relationship between genetically predicted IS and GBM. We conducted a Mendelian randomization analysis utilizing genome-wide studies data on IS and GBM within European populations. The inverse variance weighted method provided the main results. We utilized Cochran's Q-test and Mendelian randomization-Egger regression to assess heterogeneity. Leave-one-out analysis was conducted to assess the impact of individual single nucleotide polymorphisms on the observed effect. Our analysis indicated no significant causal link between IS and GBM risk (odds ratio with 95% confidence interval = 0.311 [0.068-1.422], P = .132). The inverse relationship between IS and GBM was also not statistically significant (odds ratio [95% confidence interval] = 1.005 [0.997-1.012], P = .249). The Mendelian randomization-Egger method and Cochran's Q-test showed no pleiotropy between the single nucleotide polymorphisms and GBM. This study presents strong evidence indicating no significant causal link between IS and the modified risk of GBM.