Abstract P40: Declining Morbidity From Subarachnoid Hemorrhage in the Last 4 Decades: A Pooled Analysis of 13,343 Patients

Introduction: Subarachnoid hemorrhage (SAH) mortality is decreasing, but data on functional outcomes over time is lacking. Methods: We created trends of good (Glasgow Outcomes Scale [GOS] of 4 or 5) and optimal (GOS of 5) functional outcomes and mortality (GOS of 1) using linear regression in 15 SAH trials and registries from 1982 to 2014. Models adjusted for age, sex, history of hypertension, World Federation of Neurological Surgeons grade, Fisher grade, aneurysm size, location, and repair modality, and whether data was from a clinical trial or registry. Analyses were repeated separately for the clinical trials and registries. Missing data were handled with multiple imputation. Results: Overall, 13,343 SAH patients were included. 9,524 (71%) patients had good functional outcome, while 1,608 (12%) died. There was a 0.6% adjusted improvement (95% confidence interval [CI]: 0.5% to 0.7%; p<0.001) per year in good functional outcome and a 0.1% adjusted reduction (95% CI: -0.2% to -0.08%; p<0.001) per year in mortality. For patients enrolled in clinical trials, there was no change good functional outcomes (0%; 95% CI: -0.2% to 0.1%; p=0.923) or mortality (0.0% change per year; 95% CI: -0.09% to 0.1%; p=0.676). Clinical registry patients experienced a 1.2% improvement (95% CI: 1.0% to 1.4%; p<0.001) in good functional outcome and a 0.3% reduction (95% CI: -0.4% to -0.1%; p<0.001) in mortality. Conclusions: SAH morbidity and mortality decreased from the 1980s to 2010s. This data can be helpful for researchers planning trials, clinicians discussing expected outcomes with patients and family members, and healthcare administrators planning resource utilization.