title: Intracranial carotid artery atherosclerosis and the risk of stroke in whites: the Rotterdam Study.
abstract: OBJECTIVE
  Intracranial atherosclerosis represents a relatively unexplored, but potentially important, cause of stroke in a white population.
  
  
  OBJECTIVE
  To investigate the relationship between intracranial carotid artery calcification (ICAC) as a marker of intracranial atherosclerosis and the risk of stroke in whites.
  
  
  METHODS
  A population-based cohort study in the general community with 6 years of follow-up was conducted (the Rotterdam Study). Between 2003 and 2006, a random sample of 2323 stroke-free persons (mean age, 69.5 years) underwent computed tomography scanning to quantify ICAC volume. All participants were continuously monitored for the occurrence of stroke until January 1, 2012.
  
  
  METHODS
  Atherosclerotic calcification in the intracranial internal carotid arteries.
  
  
  METHODS
  Incident stroke.
  
  
  RESULTS
  During 14,055 person-years of follow-up, 91 participants had a stroke, of which 74 were ischemic. Larger ICAC volume was related to a higher risk of stroke, independent of cardiovascular risk factors, ultrasound carotid plaque score, and calcification in other vessels (fully adjusted hazard ratio per an increase of 1 SD in ICAC volume, 1.43 [95% CI, 1.04-1.96]). Intracranial carotid artery calcification contributed to 75% of all strokes; for aortic arch and extracranial carotid artery calcification this incidence was only 45% and 25%, respectively.
  
  
  CONCLUSIONS
  Our findings establish intracranial atherosclerosis as a major risk factor for stroke in the general white population and suggest that its contribution to the proportion of all strokes may be greater than that of large-artery atherosclerosis in more proximally located vessel beds.
authors.affiliation: Department of Radiology, Erasmus Medical Center, Rotterdam, the Netherlands2Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bos
authors.affiliation: Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands3Department of Neurology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Marileen L P
authors.initials: ML
authors.lastname: Portegies
authors.affiliation: Department of Radiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Aad
authors.initials: A
authors.lastname: van der Lugt
authors.affiliation: Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Michiel J
authors.initials: MJ
authors.lastname: Bos
authors.affiliation: Department of Neurology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Koudstaal
authors.affiliation: Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Albert
authors.initials: A
authors.lastname: Hofman
authors.affiliation: Department of Radiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Gabriel P
authors.initials: GP
authors.lastname: Krestin
authors.affiliation: Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Oscar H
authors.initials: OH
authors.lastname: Franco
authors.affiliation: Department of Radiology, Erasmus Medical Center, Rotterdam, the Netherlands2Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: Meike W
authors.initials: MW
authors.lastname: Vernooij
authors.affiliation: Department of Radiology, Erasmus Medical Center, Rotterdam, the Netherlands2Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands3Department of Neurology, Erasmus Medical Center, Rotterdam, the Netherlands.
authors.forename: M Arfan
authors.initials: MA
authors.lastname: Ikram
mesh_terms: D000368:Aged; D002340:Carotid Artery Diseases / Q000175:diagnosis* / Q000208:ethnology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002537:Intracranial Arteriosclerosis / Q000175:diagnosis* / Q000208:ethnology*; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000208:ethnology; D011159:Population Surveillance / Q000379:methods; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke; D044465:White People / Q000208:ethnology*