Risk Factor for Poor Outcome in Elderly Patients with Aneurysmal Subarachnoid Hemorrhage Based on Post Hoc Analysis of the Modified WFNS Scale Study

Objective: There is currently no precise guide for the treatment and management of elderly patients with aneurysmal subarachnoid hemorrhage (aSAH). Thus, the aim of this study was to clarify the factors of poor outcome and mortality in elderly patients with aSAH. Methods: In the modified World Federation of Neurosurgical Societies (mWFNS) scale study, 1124 patients were divided into 2 groups, elderly (age ≥65 years) and non-elderly (age <65 years), with aSAH investigated between October 2010 and March 2013 in Japan. The odds ratio (OR) and 95% confidence interval (CI) of each risk factor was calculated through multivariate logistic regression analysis for poor outcomes, as indicated by the modified Rankin Scale (mRS) score ≥3 and mortality at 3 months after onset in each group. Results: Both groups demonstrated that the mWFNS scale was significant as a grade order risk factor for poor outcomes and mortality associated with disease. In the elderly group, risk factors for poor outcomes at 3 months after onset were older age (OR 1.10, 95% CI 1.06–1.14), male sex (OR 2.03, 95% CI 1.10–3.73), and severe cerebral vasospasm category (OR 10.13, 95% CI 4.30–23.87). Risk factors for mortality at 3 months after onset were older age (OR 1.06, 95% CI 1.01–1.11) and severe vasospasm category (OR 2.17, 95% CI 1.00–4.72). Conclusions: The mWFNS scale is a useful prognostic predictor for both non-elderly and elderly patients with aSAH. Elderly male patients with aSAH presenting with severe vasospasm should be managed more carefully.