Anterior Circulation Thrombectomy in Patients With Low National Institutes of Health Stroke Scale Score: Analysis of the National Inpatient Sample

Abstract

Prior studies have shown benefit for endovascular therapy (EVT) in patients with large‐vessel occlusion and severe deficits, as captured by the National Institutes of Health Stroke Scale. However the benefit of EVT in patients with National Institutes of Health Stroke Scale score <6 is unclear. We queried the National Inpatient Sample (2018–2020) for patients with a large‐vessel occlusion of the internal carotid or middle cerebral artery with a National Institutes of Health Stroke Scale score <6, and compared outcomes between patients treated with EVT versus best medical management, using propensity score matching. The primary outcome was routine discharge (home or self‐care). Secondary outcomes were in‐hospital mortality, intracerebral hemorrhage, and length of stay. Primary and secondary outcomes were evaluated using multivariable regression adjusted for baseline characteristics, stroke severity, and treatment with thrombolysis. Of the 212 515 patients with an internal carotid artery/middle cerebral artery stroke, 49 115 met the inclusion criteria for our study. A total of 8035 patients were treated with EVT, and 41 080 were treated with best medical management. Patients treated with EVT had increased odds of routine discharge (adjusted odds ratio [OR], 1.78 [95% CI, 1.57–2.01]; P <0.001), shorter length of hospital stays (adjusted β, −0.41 [95% CI, −0.63 to −0.19]; P <0.001), and similar rates of death (adjusted OR, 0.70 [95% CI, 0.39–1.24]; P =0.22), compared with patients treated with best medical management. These relationships persisted in the propensity‐matched cohort. Patients treated with EVT compared with best medical management had greater odds of routine discharge, reduced length of stay, and no differences in intracerebral hemorrhage or early mortality. Our findings suggest potential real‐world benefit for EVT in patients with low National Institutes of Health Stroke Scale scores.