Patrick (2001) Economic evaluation of aquatic exercise for persons with osteoarthritis

Objectives and Design

This study aimed to assess the cost-effectiveness of the Arthritis Foundation’s aquatic exercise classes for individuals with osteoarthritis from a societal perspective. Conducted as a 20-week randomized trial, the study focused on evaluating the cost per quality-adjusted life year (QALY) gained, using data from the trial to estimate outcomes.

Subjects and Methodology

A total of 249 adults aged 55 to 75 from Washington State, diagnosed with osteoarthritis by a physician, were recruited to participate in aquatic classes. The economic evaluation was based on the Quality of Well-Being Scale (QWB) and the Current Health Desirability Rating (CHDR), supplemented by the arthritis-specific Health Assessment Questionnaire (HAQ), the Center for Epidemiologic Studies-Depression Scale (CES-D), and the Perceived Quality of Life Scale (PQOL). These measures were collected at baseline and post-class to estimate QALYs, while healthcare facility usage was assessed through diaries/questionnaires, with costs estimated using Medicare reimbursement rates.

Results

Participants in the aquatic exercise program reported similar (QWB) or better (CHDR, HAQ, PQOL) health-related quality of life compared to controls. Improved outcomes were associated with regular class attendance. The cost/QALY gained, discounted at 3%, was estimated at $205,186 using the QWB and $32,643 using the CHDR.

Conclusion

The cost-effectiveness of aquatic exercise exceeded the $50,000 per QALY gained threshold when using the community-weighted outcome but was below this threshold with the participant-weighted measure. The study highlighted the potential benefits of aquatic exercise for osteoarthritis patients, albeit with significant variability in cost-effectiveness.