Longer Door-In–Door-Out Times Linked to Worse Outcomes in Acute Ischemic Stroke: Study

A new study published in the journal of The Lancet Neurology found that patients with Door-In–Door-Out (DIDO) times exceeding 90 minutes had lower odds of receiving endovascular therapy and higher risks of complications and poorer functional outcomes. This research analyzed data from the Get With The Guidelines–Stroke registry examined how DIDO time (the interval between a patient’s arrival at an initial emergency department and their departure for a specialized stroke center) affects recovery in patients with acute ischemic stroke.

The retrospective cohort study included 22,410 patients treated from January 1, 2019, to December 31, 2023. All patients had confirmed large-vessel occlusions on cerebrovascular imaging and were transferred from acute care hospitals to comprehensive stroke centers for possible endovascular therapy that can dramatically improve survival and independence if performed quickly.

The median DIDO time was 121 minutes. However, outcomes varied sharply depending on how long patients remained at the first hospital. When compared with patients transferred within 90 minutes, those with longer DIDO times faced progressively worse functional outcomes at hospital discharge.

The patients whose transfers took 91–180 minutes had a 29% higher adjusted odds of worse disability. That risk rose to 49% for those waiting 181–270 minutes, and 70% for patients whose transfer exceeded 270 minutes. Functional outcomes were measured using the modified Rankin Scale (mRS), where, longer DIDO times were consistently associated with worse shifts in disability scores.

The delays also reduced the likelihood that patients ultimately received endovascular therapy at the receiving hospital. While 75.8% of all transferred patients underwent the procedure, those with prolonged DIDO times were significantly less likely to receive it. For example, patients delayed beyond 270 minutes had roughly one-third the odds of receiving endovascular therapy compared with those transferred within 90 minutes. Beyond disability scores and treatment rates, prolonged DIDO times were linked to lower rates of independent ambulation at discharge and higher complication rates following reperfusion therapy.

The study population had a median age of 70 years; roughly half were women. The cohort was racially diverse, with nearly 26% of patients identifying as Black, Hispanic, or other non-White groups. Every minute of delay increases the likelihood of permanent neurological damage. While much attention has focused on rapid arrival to hospital and swift in-hospital treatment, this study highlights that interhospital transfer efficiency is equally critical.

Reference:

Royan, R., Stamm, B., Giurcanu, M., Messe, S. R., Jauch, E. C., Saver, J. L., & Prabhakaran, S. (2026). Door-in-door-out times and outcomes in patients with acute ischaemic stroke transferred for endovascular therapy in the USA: a retrospective cohort study. Lancet Neurology, 25(2), 160–169. https://doi.org/10.1016/S1474-4422(25)00478-8