Long-term outcomes and resource utilization of endovascular versus open repair of abdominal aortic aneurysms in Ontario

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).

Conclusion

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.