Trends in Incidence and Mortality by Hospital Teaching Status and Location in Aneurysmal Subarachnoid Hemorrhage

Abstract

Few studies have examined the impact of teaching status and location on outcomes in subarachnoid hemorrhage (SAH). The objective of the present study was to compare mortality and functional outcomes among urban teaching, urban nonteaching, and rural centers for hospitalizations with SAH. The National Inpatient Sample for years 2003-2016 was queried for hospitalizations with aneurysmal SAH from 2003 to 2017. Cohorts treated at urban teaching, urban nonteaching, and rural centers were compared with the urban teaching center cohort acting as the reference. The National Inpatient Sample Subarachnoid Hemorrhage Outcome Measure, a validated measure of SAH functional outcome, was used as a coprimary outcome with mortality. Multivariable models adjusted for age, sex, NIH-SSS score, hypertension, and hospital bed size. Trends in SAH mortality rates were calculated. There were 379,716 SAH hospitalizations at urban teaching centers, 105,638 at urban nonteaching centers, and 17,165 at rural centers. Adjusted mortality rates for urban teaching centers were lower than urban nonteaching (21.90% vs. 25.00%, P < 0.0001) and rural (21.90% vs. 30.90%, P < 0.0001) centers. While urban teaching (24.74% to 21.22%) and urban nonteaching (24.78% to 23.68%) had decreases in mortality rates over the study period, rural hospitals showed increased mortality rates (25.67% to 33.38%). Rural and urban nonteaching centers have higher rates of mortality from SAH than urban teaching centers. Further study is necessary to understand drivers of these differences.