title: The stroke-thrombolytic predictive instrument: a predictive instrument for intravenous thrombolysis in acute ischemic stroke.
abstract: OBJECTIVE
  Many patients with ischemic stroke eligible for recombinant tissue plasminogen activator (rt-PA) are not treated in part because of the risks and benefits perceived by treating physicians. Therefore, we aimed to develop a Stroke-Thrombolytic Predictive Instrument (TPI) to aid physicians considering thrombolysis for stroke.
  
  
  METHODS
  Using data from 5 major randomized clinical trials (n=2184) testing rt-PA in the 0- to 6-hour window, we developed logistic regression equations using clinical variables as potential predictors of a good outcome (modified Rankin Scale score < or =1) and of a catastrophic outcome (modified Rankin Scale score > or =5), with and without rt-PA. The models were internally validated using bootstrap re-sampling.
  
  
  RESULTS
  To predict good outcome, in addition to rt-PA treatment, 7 variables significantly affected prognosis and/or the treatment-effect of rt-PA: age, diabetes, stroke severity, sex, previous stroke, systolic blood pressure, and time from symptom onset. To predict catastrophic outcome, only age, stroke severity, and serum glucose were significant; rt-PA treatment was not. For patients treated within 3 hours, the median predicted probability of a good outcome with rt-PA was 42.9% (interquartile range [IQR]=18.6% to 64.7%) versus 25.3% (IQR=9.8% to 46.2%) without rt-PA; the median predicted absolute benefit was 12.5% (IQR=5.1% to 21.0%). The median probability for a catastrophic outcome, with or without, rt-PA was 15.2% (IQR=8.0% to 31.2%). The area under the receiver-operator characteristic curve was 0.788 for the model predicting good outcome and 0.775 for the model predicting bad outcome.
  
  
  CONCLUSIONS
  The Stroke-TPI predicts good and bad functional outcomes with and without thrombolysis. Incorporated into a usable tool, it may assist in decision-making.
authors.affiliation: Institute for Clinical Research and Health Policy Studies, Tufts-New England Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA. Dkent1@tufts-nemc.org
authors.forename: David M
authors.initials: DM
authors.lastname: Kent
authors.forename: Harry P
authors.initials: HP
authors.lastname: Selker
authors.forename: Robin
authors.initials: R
authors.lastname: Ruthazer
authors.forename: Erich
authors.initials: E
authors.lastname: Bluhmki
authors.forename: Werner
authors.initials: W
authors.lastname: Hacke
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000175:diagnosis* / Q000188:drug therapy* / Q000453:epidemiology; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D020521:Stroke / Q000175:diagnosis* / Q000188:drug therapy* / Q000453:epidemiology; D015912:Thrombolytic Therapy / Q000379:methods; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator