title: Population based randomised controlled trial on impact of screening on mortality from abdominal aortic aneurysm.
abstract: OBJECTIVE
  To assess whether screening for abdominal aortic aneurysms in men reduces mortality.
  
  
  METHODS
  Population based randomised controlled trial of ultrasound screening, with intention to treat analysis of age standardised mortality.
  
  
  METHODS
  Community based screening programme in Western Australia.
  
  
  METHODS
  41,000 men aged 65-83 years randomised to intervention and control groups.
  
  
  METHODS
  Invitation to ultrasound screening.
  
  
  METHODS
  Deaths from abdominal aortic aneurysm in the five years after the start of screening.
  
  
  RESULTS
  The corrected response to invitation to screening was 70%. The crude prevalence was 7.2% for aortic diameter > or = 30 mm and 0.5% for diameter > or = 55 mm. Twice as many men in the intervention group than in the control group underwent elective surgery for abdominal aortic aneurysm (107 v 54, P = 0.002, chi2 test). Between scheduled screening and the end of follow up 18 men in the intervention group and 25 in the control group died from abdominal aortic aneurysm, yielding a mortality ratio of 0.61 (95% confidence interval 0.33 to 1.11). Any benefit was almost entirely in men aged between 65 and 75 years, where the ratio was reduced to 0.19 (0.04 to 0.89).
  
  
  CONCLUSIONS
  At a whole population level screening for abdominal aortic aneurysms was not effective in men aged 65-83 years and did not reduce overall death rates. The success of screening depends on choice of target age group and the exclusion of ineligible men. It is also important to assess the current rate of elective surgery for abdominal aortic aneurysm as in some communities this may already approach a level that reduces the potential benefit of population based screening.
authors.affiliation: School of Surgery and Pathology, University of Western Australia, Fremantle Hospital, PO Box 480, Fremantle, WA 6959, Australia. pnorman@cyllene.uwa.edu.au
authors.forename: Paul E
authors.initials: PE
authors.lastname: Norman
authors.forename: Konrad
authors.initials: K
authors.lastname: Jamrozik
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lawrence-Brown
authors.forename: Max T Q
authors.initials: MT
authors.lastname: Le
authors.forename: Carole A
authors.initials: CA
authors.lastname: Spencer
authors.forename: Raywin J
authors.initials: RJ
authors.lastname: Tuohy
authors.forename: Richard W
authors.initials: RW
authors.lastname: Parsons
authors.forename: James A
authors.initials: JA
authors.lastname: Dickinson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging* / Q000401:mortality / Q000601:surgery; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D011187:Posture; D015995:Prevalence; D015996:Survival Rate; D014463:Ultrasonography; D014904:Western Australia / Q000453:epidemiology