Interaction between stroke severity and quality indicators of acute stroke care: a single-center retrospective analysis

Ischemic stroke leads to substantial mortality and morbidity worldwide. Door-to-CT time, door-to-needle time (DNT), and door-to-groin time (DGT) are important quality indicators of stroke care. However, patient characteristics remain important determinants of outcome as well. In this single-center study, we investigated the interaction between these quality indicators and stroke severity regarding long-term functional outcome. All consecutive stroke patients treated at the ZOL stroke center, Genk, Belgium, between 2017 and 2020 were included in this retrospective observational study. Stroke severity was graded as “mild” if National Institutes of Health Stroke Scale (NIHSS) was equal to or lower than 8, “moderate” if NIHSS was between 9 and 15, and “severe” if NIHSS was higher than 16. Modified Rankin Scale (mRS) scores were collected before and 3 months after stroke. Ordinal regression analysis with correction for patient characteristics of functional outcome was done. A total of 1255 patients were included, of which 84% suffered an ischemic CVA (n = 1052) and 16% a TIA (n = 203). The proportion of patients treated conservatively or with thrombolysis, thrombectomy, or the combination of both differed according to stroke severity (p < 0.0001). Door-to-CT time was longer in mild and moderate stroke (p < 0.0001). Median DNT also differed between stroke categories: 46 (IQR 31–70) min for mild vs. 36 (25–56) min for moderate vs. 30 (21–45) min for severe stroke (p = 0.0002). Median DGT did not differ between stroke severity categories (p = 0.15). NIHSS on admission and pre-stroke mRS were independently associated with mRS at 90 days. Operational performance, reflected in door-to-CT time and DNT, was worse in patients with mild and moderate stroke severity. DNT was also associated with functional outcome in our center, along with pre-stroke mRS, NIHSS on admission and age.