title: Atherosclerosis in abdominal aortic aneurysms: a causal event or a process running in parallel? The Tromsø study.
abstract: OBJECTIVE
  The pathogenesis of abdominal aortic aneurysm (AAA) formation is poorly understood. We investigated the relationship between carotid, femoral, and coronary atherosclerosis and abdominal aortic diameter, and whether atherosclerosis was a risk marker for AAA.
  
  
  RESULTS
  Ultrasound of the right carotid artery, the common femoral artery, and the abdominal aorta was performed in 6446 men and women from a general population. The burden of atherosclerosis was assessed as carotid total plaque area, common femoral lumen diameter, and self-reported coronary heart disease. An AAA was defined as maximal infrarenal aortic diameter > or =30 mm. No dose-response relationship was found between carotid atherosclerosis and abdominal aortic diameter <27 mm. However, significantly more atherosclerosis and coronary heart disease was found in aortic diameter > or =27 mm and in AAAs. The age- and sex-adjusted odds ratio (OR) (95% CI) for AAA in the top total plaque area quintile was 2.3 (1.5 to 3.4), as compared with subjects without plaques. The adjusted OR (95% CI) was 1.7 (1.1 to 2.6). No independent association was found between femoral lumen diameter and AAA.
  
  
  CONCLUSIONS
  The lack of a consistent dose-response relationship between atherosclerosis and abdominal aortic diameter suggests that atherosclerosis may not be a causal event in AAA but develops in parallel with or secondary to aneurismal dilatation.
authors.affiliation: Department of Neurology, University Hospital North Norway, N-9038 Tromsø, Norway. sh_johnsen@live.no
authors.forename: Stein Harald
authors.initials: SH
authors.lastname: Johnsen
authors.forename: Signe Helene
authors.initials: SH
authors.lastname: Forsdahl
authors.forename: Kulbir
authors.initials: K
authors.lastname: Singh
authors.forename: Bjarne Koster
authors.initials: BK
authors.lastname: Jacobsen
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000453:epidemiology*; D050197:Atherosclerosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D002340:Carotid Artery Diseases / Q000453:epidemiology*; D015897:Comorbidity; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000453:epidemiology*; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D011159:Population Surveillance; D015995:Prevalence; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D014463:Ultrasonography