Cost–utility analysis of interventions to improve effectiveness of exercise therapy for adults with knee osteoarthritis: the BEEP trial

OBJECTIVES: Evidence regarding the cost-effectiveness of enhancing physical therapy exercise programmes in order to improve outcomes for patients with knee OA remains unclear. This study investigates the cost-effectiveness of two enhanced physical therapy interventions compared with usual physical therapy care (UC) for adults with knee OA. METHODS: A trial-based cost–utility analysis of individually tailored exercise (ITE) or targeted exercise adherence (TEA) compared with UC was undertaken over a period of 18 months. Patient-level costs were obtained, and effectiveness was measured in terms of quality-adjusted life years (QALYs), allowing the calculation of cost per QALY gained from a base-case UK health-care perspective. RESULTS: The UC group was associated with lower National Health Service (NHS) costs [ITE-UC: £273.30, 95% CI: £−62.10 to £562.60; TEA-UC: £141.80, 95% CI: £−135.60 to £408.10)] and slightly higher QALY gains (ITE-UC: −0.015, 95% CI: −0.057 to 0.026; TEA-UC: −0.003, 95% CI: −0.045 to 0.038). In the base case, UC was the most likely cost-effective option (probability <40% of ITE or TEA cost-effective at £20 000/QALY). Differences in total costs were attributable to intervention costs, number of visits to NHS consultants and knee surgery, which were higher in both ITE and TEA groups. CONCLUSION: This is the first economic evaluation comparing usual physical therapy care vs enhanced exercise interventions for knee OA that involves greater exercise individualization, supervision and progression or that focuses on exercise and physical activity adherence over the longer term. Our findings show that UC is likely to be the most cost-effective option. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 93634563. TRIAL PROTOCOL: Full details of the trial protocol can be found in the Supplementary Appendix, available with the full text of this article at http://www.biomedcentral.com/1471-2474/15/254 doi: 10.1186/1471-2474-15-254