National Trends of Interhospital Transfers for Aneurysmal Subarachnoid Hemorrhage in the United States

Abstract

Background The American Heart Association guidelines recommend transferring patients with aneurysmal subarachnoid hemorrhage (aSAH) to high‐volume centers. The purpose of this study was to describe national trends in interhospital transfers (IHTs) for patients with aSAH in the United States. Methods We performed a cross‐sectional analysis of Nationwide Inpatient Sample (2008–2014) in adults hospitalized for aSAH. We performed weighted analyses using the χ 2 test, Student t‐test, and Cochran‐Armitage trend test. Multivariate survey logistic regression analysis with weighted algorithm modeling was performed to evaluate in‐hospital mortality and discharge disposition. Results Of 146 461 aSAH hospitalizations, 53 289 (36.38%) patients underwent IHT and 93 172 (63.62%) patients did not. There was a significant increase in the prevalence of IHT for aSAH (31.66% in 2008 to 39.91% in 2014; P ‐trend<0.0001). Patients with aSAH who underwent IHT were younger (57 versus 59 years) and were more often women (62.71% versus 61.35%), White race (70.65% versus 63.93%), and private insurance holders (39.62% versus 36.14%) compared with patients with aSAH who did not undergo IHT ( P <0.0001). Comparing aSAH sources of admission, more patients with aSAH at large hospitals (82.68% versus 75.14%) and urban teaching hospitals (90.43% versus 71.44%) had undergone IHT ( P <0.0001). The patients with aSAH with IHT had lower prevalence and odds of all‐cause in‐hospital mortality (15.49% versus 20.12%; adjusted odds ratio, 0.85 [95% CI, 0.79–0.91]), longer length of stay (14 versus 11 days), and higher hospitalization costs ($213 852 versus $170 834) compared with patients without IHT ( P <0.0001). The discharge disposition was not different among the 2 groups. Conclusions IHT has been steadily increasing for patients with aSAH over the past few years in the United States. IHT has been associated with lower odds of in‐hospital mortality, despite higher in‐hospital costs, longer length of stay, and unchanged discharge disposition in this patient population. Future studies should explore the different reasons for IHT and the prevalence of neurological deterioration during IHT.