Cost-effectiveness of supervised exercise, stenting, and optimal medical care for claudication: results from the Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) trial

Abstract

Background: Both supervised exercise (SE) and stenting (ST) improve functional status, symptoms, and quality of life compared with optimal medical care (OMC) in patients with claudication. The relative cost-effectiveness of these strategies is not well defined.

Methods and results: The Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) study randomized patients with claudication due to aortoiliac stenosis to a 6-month SE program, to ST, or to OMC. Participants who completed 6-month follow-up (n=98) were included in a health economic analysis through 18 months. Costs were assessed using resource-based methods and hospital billing data. Quality-adjusted life-years were estimated using the EQ-5D. Markov modeling based on the in-trial results was used to explore the impact of assumptions about the longer term durability of observed differences in quality of life. Through 18 months, mean healthcare costs were $5178, $9804, and $14 590 per patient for OMC, SE, and ST, respectively. Measured quality-adjusted life-years through 18 months were 1.04, 1.16, and 1.20. In our base case analysis, which assumed that observed differences in quality of life would dissipate after 5 years, the incremental cost-effectiveness ratios were $24 070 per quality-adjusted life-year gained for SE versus OMC, $41 376 for ST versus OMC, and $122 600 for ST versus SE. If the treatment effect of ST was assumed to be more durable than that of SE, the incremental cost-effectiveness ratio for ST versus SE became more favorable.

Conclusions: Both SE and ST are economically attractive by US standards relative to OMC for the treatment of claudication in patients with aortoiliac disease. ST is more expensive than SE, with uncertain incremental benefit.

Clinical trial registration url: www.clinicaltrials.gov, Unique identifier: NCT00132743.

Keywords: claudication; cost–benefit analysis; exercise; peripheral vascular disease; stents.

© 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Figures

Figure 1.

Sensitivity analysis on model time horizon. Incremental cost‐effectiveness ratios for SE vs OMC (blue line), ST vs OMC (red line), and ST vs SE (green line) are shown. In these scenarios, the health state utilities for ST and SE are assumed to become equivalent to OMC after the number of years shown on the x‐axis (base case=5 years). OMC indicates optimal medical care; QALY, quality‐adjusted life‐year; SE, supervised exercise; ST, stenting.

Figure 2.

Sensitivity analysis on the relative durability of QOL benefits. ICERs for ST vs SE are plotted on the y‐axis with varying assumptions about the durability of QOL benefit for each relative to OMC. The 3 lines represent 3 scenarios for ST: no decline in QOL over 5 years, a 50% decline, or full decline to the level of OMC. The number of months at which QOL with SE becomes equal to OMC is plotted on the x‐axis. For each ST scenario, a threshold can be defined at which ST is economically preferable to SE based on extended dominance (dashed line). ICERs indicates incremental cost‐effectiveness ratios; OMC, optimal medical care; QALY, quality adjusted life years; QOL, quality of life; SE, supervised exercise; ST, stenting.

Figure 3.

Probabilistic sensitivity analysis. Starting with the base case assumptions, all model parameters were replaced with probabibility distributions that were sampled independently over many model iterations. The probability that each option would be preferred at a given willingness‐to‐pay threshold is plotted across a range of such thresholds. OMC indicates optimal medical care; SE, supervised exercise; ST, stenting.