Treatment of Spontaneous Subarachnoid Hemorrhage: A 20-Year National Inpatient Sample Review.

Background: Aneurysmal subarachnoid hemorrhage (aSAH) is a major source of morbidity and mortality, and its management has undergone foundational changes over thepast 2 decades. We reviewed the National Inpatient Sample to outline the changes in severity of illness, surgical management, and patient outcomes over time. Methods: A retrospective cohort of admissions for spontaneous SAH in the National Inpatient Sample from 2001 to 2020 was reviewed, including those who underwent microsurgical or endovascular surgery to secure a ruptured aneurysm. National incidence was calculated, and multivariable regression was used to identify changes in incidence and outcome through time, segmented by epoch. Results: Review of the National Inpatient Sample identified 448 655 patients with SAH, of whom 181 590 underwent surgical aneurysm treatment. The incidence of spontaneous SAH fell -0.097 per 100 000 person-years each year (95%CI, -0.144 to -0.049). Among patients surgically treated for aneurysmal SAH, the proportion of patients <50 years old fell from 40% to 30% between first and final epochs, and the proportion of those in the lowest stroke scale category, roughly equivalent to Hunt and Hess grade 1 or 2, fell from 66% to 45%. The proportion treated by microsurgery fell from 70% to 23% in favor of endovascular surgery. Hospital mortality among these treated cases was stable at 13% throughout the study period despite increasing illness severity indices. After adjustment, there was a 42% reduction of odds of hospital mortality in the final epoch compared with the first. Conclusion: The incidence of hospitalization for spontaneous SAH fell between 2001 and 2020. Patients undergoing surgery to secure an aneurysm were more severely ill through time yet experienced a stable hospital mortality rate.