Risk factors for cerebral vasospasm following arteriovenous malformation-related hemorrhage: a systematic review and meta-analysis.

Cerebral vasospasm (CVS) is a severe complication associated with significant morbidity and in-hospital mortality. While well characterized in aSAH, its occurrence following AVM-related hemorrhage remains less understood. To address this gap, a meta-analysis adhering to PRISMA guidelines was conducted, with two independent authors searching PubMed, Scopus, and Web of Science from inception to July 2024, seeking studies on CVS risk factors following AVM-related hemorrhage. Study quality was assessed using the Newcastle-Ottawa Scale (NOS). Dichotomous variables were pooled into an overriding odds ratio (OR) with a 95% confidence interval (CI), while continuous variables were analyzed using the mean difference (MD) with a 95% CI, both using a random-effects model. Out of 2360 screened articles, 4 studies met the inclusion criteria, totaling 7483 AVM-related hemorrhage patients, 958 of whom developed CVS. All studies were rated high quality, according to NOS. A total of 10 extractable demographic, behavioral, clinical, and radiographic variables reported in the literature were assessed. The following CVS risk factors were statistically significant: younger age (MD = -4.99; 95% CI [-9.40 to -0.57]; p = 0.03), female sex (OR = 1.72; 95% CI [1.50-1.98]; p < 0.00001), and intraventricular hemorrhage (OR = 1.24; 95% CI [1.04-1.48]; p = 0.02). Subarachnoid hemorrhage was close to significance (OR = 1.17; 95% CI [1.00-1.36]; p = 0.05). This is the first systematic review and meta-analysis to identify risk factors for CVS in the context of AVM-related hemorrhage. The presented findings may aid clinicians in recognizing high-risk individuals. Further research is warranted to develop a reliable risk scoring system that can predict AVM-associated CVS in clinical settings and to further explore the differences between CVS following aSAH and AVM-related hemorrhage.