title: A comparison between the short term and long term benefits of screening for abdominal aortic aneurysms from the Huntingdon Aneurysm screening programme.
abstract: BACKGROUND
  The UK Multicentre Aneurysm Screening Study (MASS) showed a 44% reduction in AAA-related mortality after 4 years and predicted an increased number of deaths prevented in the longer term. We aim to compare the 5 and 13 years benefit from aneurysm screening in the Huntingdon Aneurysm screening programme.
  
  
  METHODS
  Incidence and mortality of ruptured AAA (RAAA) after 5 and 13 years of screening in a population based aneurysm screening program.
  
  
  RESULTS
  Five years of screening resulted in a reduction in the incidence of RAAA of 49% (95% CI: 3-74%). Nine out of 11 ruptures in the invited group did not survive (mortality 82%; 95% CI: 48-98%) compared to 38 non-survivors from 51 ruptures in the control group (mortality 75%; 95% CI: 60-86%). Five years of screening resulted in an RAAA-related mortality reduction of 45% (95% CI: -15 to 74%). After 13 years of screening the incidence of RAAA was reduced by 73% (95% CI: 58-82%). Twenty-one out of 29 ruptures in the invited group did not survive (mortality 72%; 95% CI: 53-87%) compared to 64 non-survivors from 82 ruptures in the control group (mortality 78%; 95% CI: 68-86%). Thirteen years screening resulted in a reduction of mortality from RAAA of 75% (95% CI: 58-84%). The number needed to screen to prevent one death reduced from 1380 after 5 years to 505 after 13 years. The number of elective AAA operations needed to prevent one death reduced from 6 after 5 years to 4 after 13 years.
  
  
  CONCLUSIONS
  AAA screening becomes increasingly beneficial as screening continues over the longer term. Benefits continue to increase after screening has ceased.
authors.affiliation: University Department of Vascular Surgery, Research Institute, Birmingham Heartlands Hospital, Birmingham, UK. abmw100@doctors.org.uk
authors.forename: T
authors.initials: T
authors.lastname: Wilmink
authors.forename: M W C
authors.initials: MW
authors.lastname: Claridge
authors.forename: A
authors.initials: A
authors.lastname: Fries
authors.forename: O
authors.initials: O
authors.lastname: Will
authors.forename: C S
authors.initials: CS
authors.lastname: Hubbard
authors.forename: D J
authors.initials: DJ
authors.lastname: Adam
authors.forename: C R G
authors.initials: CR
authors.lastname: Quick
authors.forename: A W
authors.initials: AW
authors.lastname: Bradbury
mesh_terms: D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D001019:Aortic Rupture / Q000453:epidemiology* / Q000401:mortality / Q000517:prevention & control; D002986:Clinical Trials as Topic; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D016019:Survival Analysis; D013997:Time Factors; D006113:United Kingdom / Q000453:epidemiology