Background: Guidelines recommend DIDO (Door-In-Door-Out) time <120 minutes at the transferring emergency department (ED); however, it is unknown whether inter-hospital transfer times are related to clinical outcomes. Methods: Retrospective, observational cohort study using US registry data from GWTG-Stroke participating hospitals. Patients age ≥18 years with intracerebral hemorrhage (ICH) or subarachnoid hemorrhage (SAH) from January 1, 2019 to July 31, 2022 who were transferred from the ED to a GWTG-participating receiving hospital. Outcomes included discharge modified Rankin Score (mRS) 0-3 vs 4-6; ability to ambulate independently at discharge; and in-hospital mortality at the receiving hospital. Results: In total, 19,708 ICH patients were included, with median age 68.0 years (IQR 57.0-78.0), 46.2% female, 65.2% White, 16.8% Black, and 8.5% Hispanic. 7,757 SAH patients were included, with median age 59.0 years (IQR 49.0-69.0), 62.7% female, 62.0% White, 14.6% Black, and 11.9% Hispanic. For ICH patients, increasing DIDO time was associated with greater odds of mRS 0-3 vs 4-6 at discharge in the unadjusted analyses (DIDO 91-180 mins, OR 1.15 [1.04-1.27]; 181-270 mins, OR 1.51 [1.33, 1.71]; >270 mins, OR 1.83 [1.58, 2.11]; vs DIDO < 90 mins as reference; P<.0001), but these associations became statistically non-significant in the adjusted analyses. Similar results were seen for mRS at discharge in SAH patients. In both ICH and SAH patients, longer DIDO times were associated with greater odds of independent ambulation at discharge and lower odds of in-hospital mortality. Conclusion: DIDO times were inversely related to in-hospital mortality, ability to ambulate independently at discharge, but not discharge mRS for patients with ICH and SAH. These findings may suggest that a longer period of stabilization in the initial ED may be associated with better outcomes from hemorrhagic stroke and that current interhospital transfer protocols currently expedite transfer of the sickest patients. Prospective studies are needed to balance ED stabilization with arrival at a definitive destination in patients with hemorrhagic stroke.

RR receives funding from the National Institute of Minority Health and Health Disparities though this work was not supported by this grant. PP receives funding from the National Institutes of Health Agency for Healthcare Research and Quality (AHRQ) (K08HS029208). SP receives funding from the AHRQ (R18HS027264) and National Institute of Neurological Disorders and Stroke (NINDS) (U24NS107233, R25NS125609; U01NS131797). KNS reported grants from the National Institutes of Health, American Heart Association, Hyperfine, Biogen, and Bard; serves on the data safety monitoring board for Zoll and Sense; serves on the scientific advisory board for CSL Behring, Astrocyte, and Rhaeos; and holds equity in Alva outside the submitted work; in addition, Dr Sheth had a patent for Alva issued. BM reported grants from the National Institutes of Health, American Heart Association, and Duke Office of Physician-Scientist Development outside the submitted work. WJM receives funding from NIH and PCORI, however this work was not supported by any of these grants. To the best of our knowledge, the remaining authors have no conflict of interest, financial or otherwise. The Get With The Guidelines®Stroke (GWTG-Stroke) program is provided by the American Heart Association. GWTG-Stroke is sponsored, in part, by Novartis, Novo Nordisk, AstraZeneca, Bayer and HCA Healthcare. This project was supported by the Hemorrhagic Stroke Data Challenge.

The authors received no external sources of funding for this study. The Get With The Guidelines®Stroke (GWTG-Stroke) program is provided by the American Heart Association. GWTG-Stroke is sponsored, in part, by Novartis, Novo Nordisk, AstraZeneca, Bayer and HCA Healthcare. This project was supported by the Hemorrhagic Stroke Data Challenge.

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Each participating hospital received either human research approval to enroll cases without individual patient consent under the common rule, or a waiver of authorization and exemption from subsequent review by their institutional review board. The Duke Clinical Research Institute serves as the data analysis center and has an agreement to analyze the aggregate limited data for research purposes. The Institutional Review Board at Duke University Health approved this study. IQVIA (Parsippany, New Jersey) serves as the data collection and coordination center.

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