title: Blood C-reactive protein concentration with ABCD² is a better prognostic tool than ABCD² alone.
abstract: BACKGROUND
  Increased C-reactive protein (CRP) is a known predictor of vascular events in asymptomatic individuals and stroke patients. Only a few studies included transient ischaemic attack (TIA) patients. We assessed CRP levels in addition to traditional risk factors in a cohort of patients with TIA to examine the relationship of these parameters to the occurrence of ischaemic stroke.
  
  
  METHODS
  This is a prospective, longitudinal clinical evaluation of the efficacy of CRP as a prognostic indicator. CRP levels were measured in 194 TIA patients and in 1,024 asymptomatic individuals (recruited from a project on stroke prevention, the PrATO, which was ongoing at the same time in the Aosta Valley). A clinical risk score was determined using the ABCD² score in TIA patients. The area under the receiver operating characteristic curve (AUC) was used to evaluate the significance of the markers as predictors. Two models were evaluated: model 1 used the ABCD² score and model 2 used serum CRP levels in addition to the ABCD²) score. The primary outcome was an ischaemic stroke.
  
  
  RESULTS
  Within 2 years ischaemic strokes occurred in 33/194 patients. The Cox proportional hazards models, after adjustments for conventional risk factors, identified CRP levels ≥3 mg/l and ABCD² scores ≥4 as independent predictors of stroke. The corresponding AUCs were 0.565 and 0.636, based on model 1 and model 2, respectively; this represented a statistically significant difference (p = 0.043). The absolute integrated discrimination improvement was 0.0249 (p = 0.007) and the relative integrated discrimination improvement was 2.3710. The net benefit became significant from a predicted probability ≥10% and was 0.077 when based on model 1 and 0.087 when based on model 2.
  
  
  CONCLUSIONS
  Routine CRP measurements in the acute phase might be a useful tool for identifying TIA patients who are at a higher risk of ischaemic stroke. The additional use of CRP levels for the risk assessment in TIA patients improves risk definition in terms of the ABCD² score alone.
authors.affiliation: Stroke Unit, Department of Neurology, Ospedale Regionale, Viale Ginevra n 3, Aosta, Italy. gcorso@ausl.vda.it
authors.forename: Giovanni
authors.initials: G
authors.lastname: Corso
authors.forename: Edo
authors.initials: E
authors.lastname: Bottacchi
authors.forename: Adriana
authors.initials: A
authors.lastname: Brusa
authors.forename: Chiara
authors.initials: C
authors.lastname: Lia
authors.forename: Susanna
authors.initials: S
authors.lastname: Cordera
authors.forename: Guido
authors.initials: G
authors.lastname: Giardini
authors.forename: Massimo
authors.initials: M
authors.lastname: Pesenti Campagnoni
authors.forename: Massimo
authors.initials: M
authors.lastname: Veronese Morosini
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D002546:Ischemic Attack, Transient / Q000097:blood / Q000150:complications; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*; D020521:Stroke / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology*; D014463:Ultrasonography
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein