title: Factors affecting survival after endovascular aneurysm repair: results from a population based audit.
abstract: OBJECTIVE
  To determine the effect of pre-operative factors on mid-term survival of patients enrolled in an Australian audit of endovascular aneurysm repair (EVAR).
  
  
  METHODS
  Prospective longitudinal national register (audit) of patients undergoing EVAR.
  
  
  METHODS
  961 individuals who had elective or semi-urgent EVAR of abdominal aortic aneurysms were enrolled in the audit between November 1999 and May 2001. Data was contributed by 81 surgeons from 64 hospitals. Kaplan-Meier survival analysis was used to determine survival rates and factors significantly influencing survival. Parametric survival analysis with log-exponential distribution was used to estimate expected 3 and 5 year survival for different ages, ASA, creatinine and aneurysm sizes.
  
  
  RESULTS
  Overall survival was 93% at 1 year, 80% at 3 years and 67% at five years. Survival rates were found to be statistically associated with ASA, age, aneurysm size and creatinine levels. ASA has the largest effect. Five year survival rates for aneurysms >or=65 mm and <55 mm were 54% and 76% respectively. Pre-operative creatinine levels >or=160 micromol/L lowered the survival rate from 71% to 40%.
  
  
  CONCLUSIONS
  Survival for EVAR patients is strongly correlated with a number of pre-operative factors. This survival analysis provides a useful decision-making tool for surgeons particularly for individuals with smaller aneurysms.
authors.affiliation: Australian Safety and Efficacy Register of New Interventional Procedures - Surgical, Royal Australasian College of Surgeons, Stepney, SA.
authors.forename: M
authors.initials: M
authors.lastname: Boult
authors.forename: G
authors.initials: G
authors.lastname: Maddern
authors.forename: M
authors.initials: M
authors.lastname: Barnes
authors.forename: R
authors.initials: R
authors.lastname: Fitridge
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000097:blood / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D001315:Australia / Q000453:epidemiology; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects*; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D018579:Patient Selection; D011446:Prospective Studies; D012042:Registries / Q000706:statistics & numerical data; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D003404:Creatinine