A Cost-Effectiveness Analysis of Surgery for Middle-Aged Men with Severe Obstructive Sleep Apnea Intolerant of CPAP

Abstract

Study objectives: Obstructive sleep apnea (OSA) is associated with increased cardiovascular morbidity and mortality. Conventional OSA therapy necessitates indefinite continuous positive airway pressure (CPAP). Although CPAP is an effective treatment modality, up to 50% of OSA patients are intolerant of CPAP. We explore whether surgical modalities developed for those intolerant of CPAP are cost-effective.

Methods: We construct a lifetime semi-Markov model of OSA that accounts for observed increased risks of stroke, cardiovascular disease, and motor vehicle collisions for a 50-year-old male with untreated severe OSA. Using this model, we compare the cost-effectiveness of (1) no treatment, (2) CPAP only, and (3) CPAP followed by surgery (either palatopharyngeal reconstructive surgery [PPRS] or multilevel surgery [MLS]) for those intolerant to CPAP.

Results: Compared with the CPAP only strategy, CPAP followed by PPRS (CPAP-PPRS) adds 0.265 quality adjusted life years (QALYs) for an increase of $2,767 (discounted 2010 dollars) and is highly cost effective with an incremental cost-effectiveness ratio (ICER) of $10,421/QALY for a 50-year-old male with severe OSA. Compared to a CPAP-PPRS strategy, the CPAP-MLS strategy adds 0.07 QALYs at an increase of $6,213 for an ICER of $84,199/QALY. The CPAP-PPRS strategy appears cost-effective over a wide range of parameter estimates.

Conclusions: Palatopharyngeal reconstructive surgery appears cost-effective in middle-aged men with severe OSA intolerant of CPAP. Further research is warranted to better define surgical candidacy as well as short-term and long-term surgical outcomes.

Commentary: A commentary on this article appears in this issue on page 509.

Keywords: cost-effectiveness analysis; obstructive sleep apnea; sleep apnea surgery; sleep apnea syndromes.

Figure 1. Incremental cost effectiveness ratios for each treatment strategy are shown for severe OSA in a 50-year-old man.

Figure 2. Tornado diagrams for CPAP-PPRS (A) and CPAP-MLS (B) treatment strategies.

These diagrams plot the incremental cost effectiveness ratios (ICER) of the respective treatment strategies versus the CPAP only strategy (or CPAP-PPRS strategy) varying the specified parameter by ± 50%. Each plot is ordered by the highest ICER based on the high estimate.

Figure 3. Two-way sensitivity analyses examining the optimal treatment strategy for a 50-year-old man with severe OSA.

Each shaded area represents the range of values that the treatment option is most cost effective at a $50,000/QALY willingness-to-pay threshold. (A) Two-way sensitivity analysis of the decay rate for PPRS cure and success rates vis-à-vis that for MLS. (B) Two-way sensitivity analysis of initial cure rate for PPRS vis-à-vis that for MLS. (C) Two-way sensitivity analysis of success rates for PPRS vis-à-vis that for MLS assuming baseline ratios of success to cure rates. (D) Two-way sensitivity analysis of costs for PPRS and MLS.

Figure 4. Cost-effectiveness acceptability curve of four alternative treatment strategies for a 50-year-old man with severe OSA.

The graph plots the probability that a particular treatment is the most cost-effective strategy at different willingness to pay thresholds. Willingness to pay is defined as the amount that a third-party accepts to pay in order to obtain one year of health.