title: Impact of sex and age on carotid plaque instability in asymptomatic patients-results from the Munich Vascular Biobank.
abstract: BACKGROUND
  It is still a controversial issue whether carotid endarterectomy (CEA) for asymptomatic carotid stenosis is superior to best medical treatment. The aim of this study was therefore to analyze the impact of sex and age on carotid plaque instability in asymptomatic patients undergoing CEA.
  
  
  METHODS
  Atherosclerotic plaques from 465 asymptomatic patients with high-grade carotid artery stenosis (2004 - 2013) at the Munich Vascular Biobank were analyzed. Ascertainment of lesion stability/instability was performed on formalin-fixed paraffin-embedded tissue samples using hematoxylin-eosin and elastic van Gieson staining. Unstable plaques were considered lesions with a fibrous cap < 200 µm overlaying lipid-rich atheroma.
  
  
  RESULTS
  The average age of the patients was 69.3 ± 8.2 years. Independent of age, asymptomatic men had in total more frequently unstable plaques in contrast to women (41 % versus 52%, p = 0.042). No differences were found in plaque instability between age-related quartiles (< 65, 65- 69, 70 - 74, > 74 years) for female sex (p = 0.422). In men, a continuous increase in plaque instability with age was observed, without achieving statistical significance (p = 0.125). The greatest differences between male and female sex were found in the last quartile (> 74 years), without achieving statistical significance (p = 0.053). The chance of unstable carotid plaques in men was significantly higher than in women (OR = 1.562, p = 0.040). The probability of age-associated quartiles related to the first quartile demonstrated significant increase in plaque instability in the group of 65- to 69-year-old patients (OR 1.867, p = 0.024) and for patients older than 74 years (OR 1.740, p = 0.040).
  
  
  CONCLUSIONS
  Asymptomatic men had in total more frequently unstable plaques in contrast to women. Thus, male sex seems to be an additional risk factor for ischemic stroke.
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.
authors.forename: Carina
authors.initials: C
authors.lastname: Wendorff
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Wendorff
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kuehnl
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.
authors.forename: Pavlos
authors.initials: P
authors.lastname: Tsantilas
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Kallmayer
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.|2 German Centre for Cardiovascular Research, Munich, Germany.
authors.forename: Hans-Henning
authors.initials: HH
authors.lastname: Eckstein
authors.affiliation: 1 Department of Vascular and Endovascular Surgery, University Hospital Rechts der Isar, Munich, Germany.|2 German Centre for Cardiovascular Research, Munich, Germany.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Pelisek
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D058070:Asymptomatic Diseases; D002545:Brain Ischemia / Q000209:etiology; D002339:Carotid Arteries / Q000473:pathology* / Q000601:surgery; D016893:Carotid Stenosis / Q000150:complications / Q000473:pathology* / Q000601:surgery; D016009:Chi-Square Distribution; D015897:Comorbidity; D003430:Cross-Sectional Studies; D016894:Endarterectomy, Carotid; D005260:Female; D005355:Fibrosis; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D058226:Plaque, Atherosclerotic; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D012422:Rupture, Spontaneous; D012720:Severity of Illness Index; D012737:Sex Factors; D020521:Stroke / Q000209:etiology; D014015:Tissue Banks
keywords: Asymptomatic patients; aging; atherosclerotic plaque; carotid artery; sex