Prediction of long-term outcome by percent improvement after the first day of thrombolytic treatment in stroke patients

BackgroundWe investigated a method for assessing early improvement and predictive factors of early and late outcomes in patients receiving thrombolytic therapy.MethodsA total of 160 consecutive patients who received thrombolytic therapy were included in the study. Using National Institutes of Health Stroke Scale (NIHSS) scores, percent improvement [(baseline NIHSS score − 24-hour NIHSS score) / baseline NIHSS score × 100] was calculated and compared with delta (baseline NIHSS score − 24-hour NIHSS score) and with major neurological improvement (MNI, NIHSS score of 0–1 or ≥ 8 point improvement at 24 h) by receiver operating characteristic (ROC) curve analysis. Finally, we investigated the independent predictors of improvement at 24 h after the thrombolytic therapy and of favorable 3-month outcome (modified Rankin scale score 0–2).ResultsBy pairwise comparison of ROC curves, percent improvement was stronger than delta (p = 0.004) and MNI (p < 0.001) in predicting long-term outcome. First day improvement (FDI), defined as greater than 20% improvement, was a strong predictor of favorable 3-month outcome (OR 12.55, 95% CI 5.41–29.10). Recanalization (OR 3.30, 95% CI 1.28–8.45), absence of carotid T occlusion (OR 0.09, 95% CI 0.02–0.42) and hemorrhagic transformation (OR 0.25, 95% CI 0.09–0.73) were independent predictors of FDI. Independent predictors of favorable 3-month outcome were FDI, current smoking, absence of carotid T occlusion and hemorrhagic transformation.ConclusionsPercent improvement at 24 h after thrombolytic therapy is a useful surrogate marker for predicting the long-term outcome. Our findings highlight the importance of early stroke management.