Association Between Intracranial Atherosclerosis Burden and Outcomes in Aneurysmal Subarachnoid Hemorrhage
Alex Hernandez Manriquez1, Milidu Jayaweera1, Asghar Shah1, Christoph Stretz2, Karen Furie3, Shadi Yaghi1, Ali Mahta1
1Brown University, 2Rhode Island Hospital, Department of Neurology, 3RIH/Alpert Medical School of Brown University
Objective:
To test the association between intracranial atherosclerosis burden with vasospasm and outcomes in aneurysmal subarachnoid hemorrhage (aSAH).
Background:
Cerebral vasospasm is a common complication after aSAH, occurring more often in younger patients. We hypothesized that intracranial atherosclerosis, seen predominantly in older patients, affects vasospasm risk in aSAH.
Design/Methods:
We performed a retrospective study of a prospectively collected cohort of consecutive patients with aSAH admitted to an academic center between 2016 and 2023. Intracranial atherosclerosis burden was quantified by using modified Woodcock (MW) score on CT angiograms. Vasospasm was defined based on transcranial Doppler (TCD) criteria. Worse outcome was defined as 3-month modified Rankin Scale 4-6. Univariable and multivariable logistic regression were used to test the association of predictors with outcomes.
Results:
We reviewed 302 cases of aSAH (mean age 56.8 years [SD 13.3], 65% female, 70% white). Cerebral vasospasm was reported in 46% of patients and was more common in younger patients (OR 0.91 for each year increase, 95% CI 0.89-0.94; p<0.001). MW scores ranged from 0 to 3 (median 0, IQR 0-1) with higher scores in older patients (beta coefficient 0.019, 95% CI 0.009-0.028; p<0.001). Higher MW score was associated with lower risk of vasospasm (odds ratio 0.52 per point increase, 95% CI 0.36-0.78; p=0.001). There was an inverse correlation between MW scores and severity of vasospasm (beta coefficient -0.29, 95% CI -0.48, -0.1; p=0.003). However, MW score was not independently associated with worse functional outcome (p=0.62) when adjusted for age, Hunt and Hess grades, modified Fisher scores.
Conclusions:
Intracranial atherosclerosis is a potential mechanism for lower vasospasm rate in older SAH patients, however, it does not appear to alter functional outcome. This possibly suggests intracranial atherosclerosis may affect TCD velocities without any clinical correlation. Larger prospective studies are needed to confirm our findings.