title: Analysis of risk factors for abdominal aortic aneurysm in a cohort of more than 3 million individuals.
abstract: BACKGROUND
  Abdominal aortic aneurysm (AAA) disease is an insidious condition with an 85% chance of death after rupture. Ultrasound screening can reduce mortality, but its use is advocated only for a limited subset of the population at risk.
  
  
  METHODS
  We used data from a retrospective cohort of 3.1 million patients who completed a medical and lifestyle questionnaire and were evaluated by ultrasound imaging for the presence of AAA by Life Line Screening in 2003 to 2008. Risk factors associated with AAA were identified using multivariable logistic regression analysis.
  
  
  RESULTS
  We observed a positive association with increasing years of smoking and cigarettes smoked and a negative association with smoking cessation. Excess weight was associated with increased risk, whereas exercise and consumption of nuts, vegetables, and fruits were associated with reduced risk. Blacks, Hispanics, and Asians had lower risk of AAA than whites and Native Americans. Well-known risk factors were reaffirmed, including male gender, age, family history, and cardiovascular disease. A predictive scoring system was created that identifies aneurysms more efficiently than current criteria and includes women, nonsmokers, and individuals aged <65 years. Using this model on national statistics of risk factors prevalence, we estimated 1.1 million AAAs in the United States, of which 569,000 are among women, nonsmokers, and individuals aged <65 years.
  
  
  CONCLUSIONS
  Smoking cessation and a healthy lifestyle are associated with lower risk of AAA. We estimated that about half of the patients with AAA disease are not eligible for screening under current guidelines. We have created a high-yield screening algorithm that expands the target population for screening by including at-risk individuals not identified with existing screening criteria.
authors.affiliation: Society for Vascular Surgery Screening Task Force, Society for Vascular Surgery, Chicago, Ill, USA.
authors.forename: K Craig
authors.initials: KC
authors.lastname: Kent
authors.forename: Robert M
authors.initials: RM
authors.lastname: Zwolak
authors.forename: Natalia N
authors.initials: NN
authors.lastname: Egorova
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Riles
authors.forename: Andrew
authors.initials: A
authors.lastname: Manganaro
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Moskowitz
authors.forename: Annetine C
authors.initials: AC
authors.lastname: Gelijns
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Greco
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*; D002318:Cardiovascular Diseases / Q000150:complications / Q000453:epidemiology; D016009:Chi-Square Distribution; D015331:Cohort Studies; D004032:Diet / Q000009:adverse effects; D005006:Ethnicity; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000453:epidemiology; D016017:Odds Ratio; D010375:Pedigree; D015995:Prevalence; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013997:Time Factors; D014481:United States / Q000453:epidemiology