title: National Institutes of Health Stroke Scale Item Profiles as Predictor of Patient Outcome: External Validation on Safe Implementation of Thrombolysis in Stroke-Monitoring Study Data.
abstract: OBJECTIVE
  National Institutes of Health Stroke Scale (NIHSS) item profiles that were recently proposed and validated may prove useful for clinical prognostication and research studies. We aimed to validate the NIHSS item profiles in hyper-acute stroke patients who received thrombolysis treatment (tissue-type plasminogen activator).
  
  
  METHODS
  We applied the latent class analysis probabilities of the profile membership generated from the derivation study onto NIHSS data from the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST). We separately considered NIHSS data collected within 3 hours and at ≈24 hours after stroke onset to obtain 2 sets of symptom groupings. The discrimination and calibration of both sets of symptom profiles were assessed from their association with outcomes. The outcome measures included modified Rankin Scale (mRS; using full distribution and dichotomized, mRS 0-1 or back to baseline) at day 90 and mortality by 90 days.
  
  
  RESULTS
  We obtained data for 6843 patients. Ordinal analysis of mRS showed odds of better outcome across the profiles, for each set of symptom profiles, adjusted for age, sex, and prestroke mRS. Dichotomized outcomes mirrored the ordinal findings. There were significant differences in prognostic discrimination ability for the dichotomized outcome measures between the 2 sets of symptom profiles, with the latter set (ie, 24-hour symptom profiles) performing better.
  
  
  CONCLUSIONS
  The NIHSS item profiles are individually associated with functional outcome and mortality in acute stroke patients treated with tissue-type plasminogen activator. Considering profiles of NIHSS subscores rather than only the total score is informative for prognostication, particularly for assessments collected 24 hours after stroke onset.
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.). Azmil.Abdul-Rahim@glasgow.ac.uk.
authors.forename: Azmil H
authors.initials: AH
authors.lastname: Abdul-Rahim
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Rachael L
authors.initials: RL
authors.lastname: Fulton
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Heidi
authors.initials: H
authors.lastname: Sucharew
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Dawn
authors.initials: D
authors.lastname: Kleindorfer
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Pooja
authors.initials: P
authors.lastname: Khatri
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Broderick
authors.affiliation: From the Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (A.H.A.-R., R.L.F., K.R.L.); Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Centre, OH (H.S.); and Department of Neurology, University of Cincinnati College of Medicine, OH (D.K., P.K., J.P.B.).
authors.forename: Kennedy R
authors.initials: KR
authors.lastname: Lees
mesh_terms: D000368:Aged; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009316:National Institutes of Health (U.S.); D011358:Product Surveillance, Postmarketing; D012189:Retrospective Studies; D020521:Stroke / Q000188:drug therapy*; D015912:Thrombolytic Therapy; D016896:Treatment Outcome; D014481:United States
chemical_list: D005343:Fibrinolytic Agents
keywords: outcome assessment; prognosis; stroke; thrombolytic therapy; tissue-type plasminogen activator