Cost-effectiveness of abdominal aortic aneurysm repair based on aneurysm size.

Abstract

To evaluate the cost-effectiveness of endovascular repair (EVAR) for small abdominal aortic aneurysms (AAA). We developed a Markov model of a hypothetical 68-year-old cohort to determine the cost-effectiveness of early EVAR for "small" AAAs (4.0 cm-5.4 cm) compared with elective repair (open or endovascular) at the traditional cut-off of 5.5 cm. Repair options for 5.5-cm AAAs include both endovascular and open procedures. Probabilities were obtained from the literature. Costs reflected direct costs in 2007 dollars. Outcomes were reported as quality-adjusted life-years (QALYs). The model demonstrated that early EVAR for 4.0 cm-5.4 cm AAAs led to fewer QALYs at greater costs when compared with observational management with elective repair at 5.5 cm. Sensitivity analyses suggested that early EVAR of 4.6 cm-4.9 cm AAAs can be cost-effective if the long-term mortality rate after EVAR is <or=1.91% per year or if the quality of life after EVAR is improved. Likewise, if the quality of life before repair is low, EVAR for AAAs >or=4.6 cm may be cost-effective. With a >70% probability, observational management until AAA diameter is 5.5 cm will be the cost-effective option. This analysis demonstrated that early EVAR for AAAs <5.5 cm is not likely to be cost-effective compared with elective repair at 5.5 cm. However, EVAR for small AAAs may become cost-effective when differences in quality of life and mortality are considered.