Early Onset of Cerebral Vasospasm and the Mediating Impact of Secondary Infarction on In-Hospital Mortality Following Aneurysmal Subarachnoid Hemorrhage

TL;DR

This study shows that early cerebral vasospasm after brain aneurysm bleeding increases in-hospital death risk, partly due to secondary brain infarction.

Contribution

The study quantifies how early cerebral vasospasm contributes to mortality through secondary infarction in aSAH patients.

Findings

Earlier onset of cerebral vasospasm was associated with higher in-hospital mortality.

Secondary infarction mediated 28% of the effect of early vasospasm on mortality.

SVS-I occurrence was strongly linked to in-hospital death (aOR 13.47).

Abstract

Background: Cerebral vasospasm (CV) as a complication after aneurysmal subarachnoid hemorrhage (aSAH) is a major determinant of secondary vasospasm-associated ischemic infarction (SVS-I) and poor outcome. Data on the interplay among the onset of CV, SVS-I, and in-hospital mortality remain limited. Methods: We conducted a retrospective, single-center study including patients admitted with aSAH between January 2016 and May 2024 who developed treatment-relevant CV. The primary outcome was the rate of in-hospital mortality. The relationship between the onset of CV, demographics, imaging, and treatment data and the primary outcome was analyzed using logistic regression. A confounder-adjusted mediation analysis was performed to quantify the extent to which the effect of time to CV onset on in-hospital mortality was mediated by SVS-I. Results: A total of 165 patients with aSAH and treatment-relevant CV were included. The median age was 55 (IQR, 48–64), and 67.2% (111) were female. Of the included patients, 13.3% (22) died during hospitalization. In multivariable logistic regression analysis, earlier onset of treatment-relevant CV (adjusted odds ratio [aOR] 0.79; 95% CI, 0.66–0.95) and the occurrence of SVS-I (aOR 13.47; 95% CI, 2.78–65.3) were associated with the primary outcome. Mediation analysis indicated that SVS-I accounted for 28% of the effect of earlier onset of CV on in-hospital mortality. Conclusions: Twenty-eight percent of the effect of earlier onset of cerebral vasospasm on in-hospital mortality was mediated by secondary ischemic infarction. Targeting patients with early-onset vasospasm and the associated risk of infarction may reduce in-hospital mortality following aneurysmal subarachnoid hemorrhage.

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