Risk factors for incomplete functional recovery in post-stroke patients undergoing treatment in a comprehensive stroke unit

Abstract

Objective — to identify factors that are associated with incomplete functional recovery (disability) after stroke in patients who were admitted to the comprehensive stroke unit (CSU). Methods and subjects. The study included stroke in‑patients, who were admitted to our Stroke Center in 2010 to 2018, operated on the principles of the CSU. All patients were examined by a Neurologist upon admission, and their workup and treatment were in line with the recommendations of the clinical guidelines. Patient data were prospectively included in the database and retrospectively analyzed using one‑factor and multivariate analysis. Functional recovery was evaluated using the modified Rankin scale (mRS). Results. The study enrolled 764 patients (42 % of women) aged 20 to 95 years (mean age 66 years, interquartile interval [IQI] 57 — 75 years). 80 % of the patients had an ischemic stroke, and 20 % had a hemorrhagic stroke. The total baseline NIHSS score ranged from 0 to 39 points (median — 10 points, IQI 6 — 17 points). 18 % of patients were admitted to the CSU during the first 24 hours, another 19 % — on Day 2nd to 7‑th days, 7 % on Day 8‑th to 14, 15 % on Day 15‑th to 30‑th, 10 % from Day 31st to 60‑th, 13 % from Day 61st to 180‑th, and 18 % — later 180 days from stroke onset. According to the results of a single‑factor analysis, the risk of incomplete functional recovery (scores for mSR ³ 2 at discharge) is associated with numerous factors: hemorrhagic stroke (odds ratio [OR] 1.7), atherosclerotic (OR 3.6) and cardioembolic (OR 3.1) subtypes of ischemic stroke, age of the patient (OR 1.02 per each additional year), delay from the stroke onset to admission to the CSU, initial stroke severity (OR 1.3 per each additional NIHSS point), initial level of daily activities (OR 0.96 per each Bartel Index point) and disability (OR 3.5 per each additional mRS point), as well as elevated ESR, CRP and glycosylated hemoglobin levels. In the multivariant analysis, three independent predictors were identified: initial stroke severity (baseline total NIHSS score), the degree of disability at admission (mRS score), and the time from the stroke onset to the CSU admission. The area under the operational curve is AUC = 0.92 (95 % CI 0.89 — 0.94), which proves excellent quality of the prediction model and the strong link between this set of three factors and the risk of incomplete functional recovery at discharge. Conclusions. Single‑factor analysis showed that the disability after the CSU treatment is associated with many initial factors, such as patient age, admission delay, stroke type and subtype, severity and certain types of neurological deficit, disability, and laboratory tests results. In multivariate analysis, three main factors were found to be significant independent predictors of incomplete functional recovery: initial stroke severity, disability level at admission and the time from the onset of the hospitalization. The latter factor emphasizes the importance of reducing CSU admission delay.