title: Ankle-brachial index predicts stroke in the general population in addition to classical risk factors.
abstract: BACKGROUND
  Predictors of future stroke events gain importance in vascular medicine. Herein, we investigated the value of the ankle-brachial index (ABI), a simple non-invasive marker of atherosclerosis, as stroke predictor in addition to established risk factors that are part of the Framingham risk score (FRS).
  
  
  METHODS
  4299 subjects from the population-based Heinz Nixdorf Recall study (45-75 years; 47.3% men) without previous stroke, coronary heart disease or myocardial infarcts were followed up for ischemic and hemorrhagic stroke events over 109.0±23.3 months. Cox proportional hazard regressions were used to evaluate ABI as stroke predictor in addition to established vascular risk factors (age, sex, systolic blood pressure, LDL, HDL, diabetes, smoking).
  
  
  RESULTS
  104 incident strokes (93 ischemic) occurred (incidence rate: 2.69/1000 person-years). Subjects suffering stroke had significantly lower ABI values at baseline than the remaining subjects (1.03±0.22 vs. 1.13±0.14, p<0.001). In a multivariable Cox regression, ABI predicted stroke in addition to classical risk factors (hazard ratio=0.77 per 0.1, 95% confidence interval=0.69-0.86). ABI predicted stroke events in subjects above and below 65 years, both in men and women. ABI specifically influenced stroke risk in subjects belonging to the highest (>13%) and intermediate (8-13%) FRS tercile. In these subjects, stroke incidence was 28.13 and 8.13/1000 person-years, respectively, for ABI<0.9, compared with 3.97 and 2.07/1000 person-years for 0.9≤ABI≤1.3.
  
  
  CONCLUSIONS
  ABI predicts stroke in the general population, specifically in subjects with classical risk factors, where ABI identifies subjects at particularly high stroke risk.
authors: Department of Neurology, University Hospital, University of Duisburg-Essen, Hufelandstr. 55, D-45122 Essen, Germany. Electronic address: janine.gronewold@uk-essen.de.
authors: Janine
authors: J
authors: Gronewold
authors: Department of Neurology, University Hospital, University of Duisburg-Essen, Hufelandstr. 55, D-45122 Essen, Germany. Electronic address: dirk.hermann@uk-essen.de.
authors: Dirk M
authors: DM
authors: Hermann
authors: Institute of Medical Informatics, Biometry and Epidemiology, University of Duisburg-Essen, Germany. Electronic address: nils.lehmann@uk-essen.de.
authors: Nils
authors: N
authors: Lehmann
authors: Department of Angiology, Helios-Klinikum Krefeld, Germany. Electronic address: knut.kroeger@helios-kliniken.de.
authors: Knut
authors: K
authors: Kröger
authors: Institute for Health Economics and Clinical Epidemiology, University of Cologne, Germany. Electronic address: karl.lauterbach@bundestag.de.
authors: Karl
authors: K
authors: Lauterbach
authors: Institute of Epidemiology and Social Medicine, University of Münster, Germany. Electronic address: bergerk@uni-muenster.de.
authors: Klaus
authors: K
authors: Berger
authors: Department of Neurology, University Hospital, University of Duisburg-Essen, Hufelandstr. 55, D-45122 Essen, Germany. Electronic address: christian.weimar@uk-essen.de.
authors: Christian
authors: C
authors: Weimar
authors: Department of Cardiology, University Hospital, University Duisburg-Essen, Germany. Electronic address: hagen.kaelsch@uk-essen.de.
authors: Hagen I M
authors: HIM
authors: Kälsch
authors: Institute of Medical Informatics, Biometry and Epidemiology, University of Duisburg-Essen, Germany. Electronic address: susanne.moebus@uk-essen.de.
authors: Susanne
authors: S
authors: Moebus
authors: Institute of Medical Informatics, Biometry and Epidemiology, University of Duisburg-Essen, Germany. Electronic address: k-h.joeckel@uk-essen.de.
authors: Karl-Heinz
authors: KH
authors: Jöckel
authors: Department of Cardiology, University Hospital, University Duisburg-Essen, Germany. Electronic address: marcus.bauer@uk-essen.de.
authors: Marcus
authors: M
authors: Bauer
authors: Department of Cardiology, University Hospital, University Duisburg-Essen, Germany. Electronic address: erbel@uk-essen.de.
authors: Raimund
authors: R
authors: Erbel
mesh_terms: D000368:Aged; D055109:Ankle Brachial Index; D001794:Blood Pressure; D002545:Brain Ischemia / Q000453:epidemiology / Q000503:physiopathology; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology* / Q000503:physiopathology; D014505:Urban Population
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL
keywords: Peripheral artery disease; Stroke prediction; Subclinical atherosclerosis