The SCON₂A Score:a Novel Grading Scale For Predicting Hemorrhage And Outcomes After Thrombolysis

Objectives:To develop a score including novel putative predictors for predicting the risk of symptomatic intracranial hemorrhages（sICH）and outcomes after thrombolytic therapy with intravenous（IV）recombinant tissue-plasminogen activator（r-tPA）in acute ischemic stroke patients.Methods:.Data from three affiliated hospitals of Chongqing Medical University,Chongqing,China,were retrospectively reviewed.Potensial risk factors associated with sICH（European Cooperative Acute Stroke Study III）were determined using multivariate logistic regression and we developed our score according to the magnitude of logistic regression coefficients.The score was validated in another independent set.Area under the receiver operating characteristic curve（AUC-ROC）was used to assess the performance of the score.Calibration was evaluated using the Hosmer-Lemeshow goodness-of-fit method.Results:The SCON₂A score（0 to 8 points）is consisted of history of Smoke（no=1,yes=0,β=0.81）,Collateral score（≤11=2,>11=0,β=1.30）,Onset-to-needle time（≧3.5=1,<3.5=0,β=0.74）,NIH Stroke Scale on admission（>10=2,≦10=0,β=1.22）,Neutrophil percentage（≥80.0%=1,<80%=0,β=0.81）and Age（>65 years=1,≦65 years=0,β=0.89）.The SCON2A was strongly associated with sICH（OR 1.98,95%CI,1.67-2.34）and poor outcomes（OR 1.89,95%CI,1.68-2.13）.AUC-ROC in the derivation set was 0.82（95%CI,0.77-0.86）.Simular results were obtained in the validation set.The Hosmer–Lemeshow test revealed that predicted and observed event rate in both set were very close.Conclusions:The SCON₂A score is a simple,efficient,quick,and easy-to-perform scale for predicting the risk of sICH and outcome after intravenous r-tPA thrombolysis within 4.5 hours in patients with ischemic stroke,providing clinicians,patients,and relatives an understanding of the risks involved in current treatment.External validation of the score supports its generalization.