title: Validation of minor stroke definitions for thrombolysis decision making.
abstract: BACKGROUND
  Patients with low National Institutes of Health Stroke Scale (NIHSS) scores are frequently excluded from thrombolysis, but more than 25% of them remain disabled. We sought to define a validated minor stroke definition to reduce the inappropriate treatment exclusion.
  
  
  METHODS
  From an outcome database, untreated patients with an NIHSS score of 5 or less presenting within a 4.5-hour window were identified and 3-month modified Rankin Scale (mRS) outcomes were analyzed according to individual isolated symptoms and total NIHSS scores. The validity of the following minor stroke definitions were assessed: (1) the National Institute of Neurological Disorders and Stroke Tissue Plasminogen Activator (NINDS-TPA) trials' definition, (2) the total NIHSS score, varying a cutoff point from 0 to 4, and (3) our proposed definition that included an NIHSS score = 0 or an NIHSS score = 1 on the items of level of consciousness (LOC), gaze, facial palsy, sensory, or dysarthria.
  
  
  RESULTS
  Of 647 patients, 172 patients (26.6%) had a 3-month unfavorable outcome (mRS score 2-6). Favorable outcome was achieved in more than 80% of patients with an NIHSS score of 1 or less or with an isolated symptom on the LOC, gaze, facial palsy, sensory, or dysarthria item. In contrast, unfavorable outcome proportion was more than 25% in patients with an NIHSS score of 2 or more. When the NINDS-TPA trials' definition, our definition, or the definition of an NIHSS score of 1 or less were applied, more than 75% of patients with an unfavorable outcome were defined as a non-minor stroke and less than 15% of patients with an unfavorable outcome were defined as a minor stroke.
  
  
  CONCLUSIONS
  Implementation of an optimal definition of minor stroke into thrombolysis decision-making process would decrease the unfavorable outcomes in patients with low NIHSS scores.
authors.affiliation: Department of Neurology, Seoul Medical Center, Seoul, Korea.
authors.forename: Tai Hwan
authors.initials: TH
authors.lastname: Park
authors.forename: Keun-Sik
authors.initials: KS
authors.lastname: Hong
authors.forename: Jay Chol
authors.initials: JC
authors.lastname: Choi
authors.forename: Pamela
authors.initials: P
authors.lastname: Song
authors.forename: Ji Sung
authors.initials: JS
authors.lastname: Lee
authors.forename: Juneyoung
authors.initials: J
authors.lastname: Lee
authors.forename: Jong-Moo
authors.initials: JM
authors.lastname: Park
authors.forename: Kyusik
authors.initials: K
authors.lastname: Kang
authors.forename: Kyung Bok
authors.initials: KB
authors.lastname: Lee
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Cho
authors.forename: Gustavo
authors.initials: G
authors.lastname: Saposnik
authors.forename: Moon-Ku
authors.initials: MK
authors.lastname: Han
authors.forename: Hee-Joon
authors.initials: HJ
authors.lastname: Bae
mesh_terms: D000368:Aged; D003661:Decision Support Techniques; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D018579:Patient Selection; D011237:Predictive Value of Tests; D011379:Prognosis; D012042:Registries; D015203:Reproducibility of Results; D056910:Republic of Korea; D012307:Risk Factors; D012720:Severity of Illness Index; D020521:Stroke / Q000145:classification / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D009626:Terminology as Topic; D015912:Thrombolytic Therapy