title: Long-term outcomes and resource utilization of endovascular versus open repair of abdominal aortic aneurysms in Ontario.
abstract: OBJECTIVE
  Two large randomized trials showed that elective endovascular aneurysm repair (EVAR) had similar all-cause long-term mortality rates but increased costs compared with open repair for nonruptured abdominal aortic aneurysms (AAAs). Despite these data, the use of EVAR continues to increase in North America. Currently, there are very limited adjusted population-based data examining long-term outcomes and resource utilization.
  
  
  METHODS
  All patients who underwent elective AAA repair between April 2002 and March 2007 in Ontario were identified using data from hospital discharge abstracts. Patients were identified with a validated algorithm. A propensity score analysis was used to adjust for treatment allocation. Clinical outcomes included time to all-cause death and discharge to a nursing home or long-term care facility. Resource utilization outcomes included imaging utilization, hospital utilization, and reintervention rates.
  
  
  RESULTS
  Overall, 6461 patients underwent treatment of nonruptured AAAs, comprising 888 EVARs and 5573 open repairs. EVAR patients were older and had more comorbidities. The adjusted mortality was significantly lower in the EVAR group at 30 days (adjusted odds ratio [adj-OR], 0.34; 95% confidence interval [95% CI], 0.20-0.59), but long-term mortality was similar (adj-OR, 0.95; 95% CI, 0.81-1.05). EVAR patients were significantly less likely to be discharged to a nursing home or other chronic care facility (adj-OR, 0.55; 95% CI, 0.41-0.74). Imaging utilization as well as urgent and vascular readmissions were significantly higher in the EVAR group. However, the EVAR group had a significantly shorter length of stay and less intensive care unit use for the index hospitalization and decreased hospital length of stay during follow-up. There was a trend toward a slightly increased risk of reintervention with EVAR (adj-OR, 1.3; 95% CI, 0.98-1.75).
  
  
  CONCLUSIONS
  Compared with open repair, EVAR significantly reduced short-term but not long-term mortality. The EVAR patients spent less time in health institutions, including long-term care facilities, but underwent more imaging studies. Future improvements in EVAR could result in further decreases in reinterventions and subsequent radiologic monitoring.
authors.affiliation: Division of Vascular Surgery, The Ottawa Hospital, University of Ottawa, Ontario, Canada. pjetty@toh.on.ca
authors.forename: Prasad
authors.initials: P
authors.lastname: Jetty
authors.forename: Paul
authors.initials: P
authors.lastname: Hebert
authors.forename: Carl
authors.initials: C
authors.lastname: van Walraven
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D001027:Aortography / Q000706:statistics & numerical data; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000401:mortality / Q000706:statistics & numerical data*; D017558:Elective Surgical Procedures; D005260:Female; D006295:Health Resources / Q000706:statistics & numerical data*; D017052:Hospital Mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D007902:Length of Stay; D008134:Long-Term Care / Q000706:statistics & numerical data; D008297:Male; D009735:Nursing Homes / Q000706:statistics & numerical data; D016017:Odds Ratio; D009864:Ontario; D010351:Patient Discharge; D010359:Patient Readmission; D057216:Propensity Score; D016016:Proportional Hazards Models; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D013997:Time Factors; D016896:Treatment Outcome