Cost-utility of long-term exercise therapy in people with axial spondyloarthritis and severe functional limitations: a randomized, controlled trial

To evaluate the cost-utility of long-term, personalized, exercise therapy as compared to usual care in people with axial spondyloarthritis (axSpA) and severe functional limitations. A comprehensive economic evaluation was conducted from a societal perspective alongside a randomized controlled trial involving 214 participants (110 individuals assigned to the intervention group and 104 to the usual care group), with a one-year follow-up. Cost assessments encompassed both medical and non-medical costs recorded by participants and healthcare providers. Quality Adjusted Life Years (QALYs) were calculated using the EuroQol-5 Dimensions -5 Levels (EQ-5D-5L) and EuroQol Visual Analogue Scale (EQ-VAS). Costs and QALY differences were analysed using standard unequal variance t-tests according to the intention-to-treat principle and cost-effectiveness acceptability curves. In the intervention group, 93% of the participants used the intervention with an average of 41 (standard deviation, SD 15) sessions, with the mean direct costs of the intervention being €1515 (SD 724) per participant. The total mean physiotherapy costs were €1967 (SD 801) in the intervention and €514 (SD 792) in the control group, respectively. Although not statistically significant, the total societal costs also favoured the usual care group after 52-weeks, showing a difference of €657 (95% confidence interval (CI) €-3748 to €5060). QALYs were slightly and non-significantly favouring the intervention group, with a difference of 0.02 based on the EQ-5D-5 L (95% CI - 0.04 to 0.09) and 0.00 according to the EQ-VAS (95% CI -0.04 to 0.04). At a willingness-to-pay threshold of €50,000 per QALY, the intervention had a 57% likelihood of being considered the cost-effective strategy. The higher intervention costs of the long-term exercise therapy intervention were negated by savings on other healthcare and non-healthcare costs and by improved QALYs. As a result, we found no clear economic preference: long-term exercise therapy need not be withheld for economic reasons from people with axSpA and severe functional limitations. REGISTRATION NUMBER: Netherlands Trial Register NL-OMON52399, included in the International Clinical Trial Registry Platform (ICTRP) (https://trialsearch.who.int/Trial2.aspx? TrialID=NL-OMON52399).