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.