Background: Whether emergency medical services (EMS) transport improves disability outcomes compared with other transport among acute ischemic stroke (AIS) patients is unknown.
Objective: To study severity-adjusted associations of hospital arrival mode (EMS vs. other transport) with in-hospital and discharge disability outcomes.
Design: Prospective observational study.
Participants: AIS patients discharged April 2016 to October 2017 from a safety-net hospital in South Carolina.
Main measures: National Institutes of Health Stroke Scale (NIHSS) change at discharge (admission NIHSS score minus discharge NIHSS, continuous variable), 24-h NIHSS change (attaining high improvement, admission NIHSS minus 24-h NIHSS being 75th percentile or higher), door to neuroimaging (DTI) time, and IV alteplase receipt. NIHSS change was assessed within stroke severity groups, mild, moderate, and severe (admission NIHSS 0-5, 6-14, and ≥ 15, respectively).
Key results: Of 1168 patients, 838 were study-eligible (52% male, 52.4% Black, 72.2% EMS arrivals, 56.6% mild strokes). Severe and moderate stroke patients were more likely than mild stroke patients to use EMS (adjusted odds ratios, AOR [95% CI] 11.7 [5.0, 27.4] and 4.0 [2.6, 6.3], respectively). EMS arrival was associated with shorter DTI time (adjusted difference - 88.4 min) and higher likelihood of alteplase administration (AOR 5.3 [2.5, 11.4]), both key mediating variables in disability outcomes. High 24-h NIHSS improvement was more likely for EMS arrivals vs. other arrivals among moderate strokes (AOR 3.4 [1.1, 10.9]) and severe strokes (AOR > 999). EMS arrivals had substantially higher NIHSS improvement at discharge within the severe stroke group (adjusted NIHSS change at discharge, 5.9 points higher, p = 0.01). Alteplase recipients showed higher discharge NIHSS improvement than non-recipients (by 2.8 and 1.9 points among severe and moderate strokes, respectively; p = 0.01, 0.02).
Conclusions: The findings offer evidence for including stroke education as a standard of care in the primary care management of patients with stroke-risk comorbidities/lifestyle in order to minimize post-stroke disability.
Keywords: 24-h disability improvement; acute ischemic stroke; discharge disability outcome; emergency medical services use.