Predictors of Outcome in Aneurysmal Subarachnoid Hemorrhage Patients

Background and Purpose— The mortality and morbidity after aneurysmal subarachnoid hemorrhage has improved because of better diagnosis, early treatment to secure the aneurysm, and better management of disease-specific complications. With these improvements in care, it is not clear if the previously identified independent predictors of a negative outcome have changed. The aim of this study was to identify the independent predictors of an unfavorable outcome (Glasgow Outcome Score 1, 2, and 3) in aneurysmal subarachnoid hemorrhage patients. Methods— Univariate and multivariate analysis of prospectively collected data on patients presenting with an aneurysmal subarachnoid hemorrhage was performed. Outcome was assessed at discharge. Data were collected from 14 centers in the United Kingdom over a period of 4 years (September 2011–2015). Results— The median age (interquartile range) at presentation of 3341 patients with aneurysmal subarachnoid hemorrhage was 55 (18) years. Most patients were female (n=2288 68.5%), presented in good grade (2397 70%; World Federation of Neurological Surgeons grade 1 and 2), and were treated by endovascular coiling (n=2600; 75%). The independent predictors of an unfavorable outcome (95% confidence interval CI) were increasing age (odds ratio OR, 1.04; 95% CI, 1.03–1.05; P <0.001), World Federation of Neurological Surgeons grade (OR, 2.06; 95% CI, 1.91–2.22; P <0.001), preoperative rebleeding (OR, 7.41; 95% CI, 4.48–12.30; P <0.001), need for cerebrospinal fluid diversion (OR, 3.25; 95% CI, 2.58–4.09; P <0.001), and delayed cerebral ischemia (OR, 2.21; 95% CI, 1.72–2.83; P <0.001). Conclusions— These data suggest that potentially modifiable risk factors of preoperative rebleeding and delayed cerebral ischemia are associated with unfavorable outcomes. Understanding the reasons why patients requiring cerebrospinal fluid diversion have 3.25-fold higher adjusted odds of a poor outcome at discharge needs to be studied.