Cost-effectiveness of Spa treatment for fibromyalgia: general health improvement is not for free

Objectives. To estimate the cost-effectiveness of an adjuvant treatment course of spa treatment compared with usual care only in patients with fibromyalgia syndrome (FM). Methods. 134 patients with FM, selected from a rheumatology outpatient department and from members of the Dutch FM patient association were randomly assigned to a 21/2 week spa treatment course in Tunisia or to usual care only. Results are expressed as quality-adjusted life years (QALYs) for a 6-month as well as a 12-month time horizon. Utilities were derived form the Short Form 6D (SF-6D) scores and the visual analogue scale (VAS) rating general health. Costs were reported from societal perspective. Mean incremental cost per patient and the incremental cost utility ratio (ICER) were calculated; 95% confidence intervals (Cis) were estimated using double-sided bootstrapping. Results. The data of 128 (55 spa and 73 controls) of the 134 patients (96%) could be used for analysis. Improvement in general health was found in the spa group until 6 months of follow-up by both the SF-6D (AUC 0.32 vs 0.30, P< 0.05) and the VAS (AUC 0.23 vs 0.19, P< 0.01). After Ilyr no significant between-group differences were found. Mean incremental cost of spa treatment was sic1311 per patient (95% CI 369-2439), equalling the cost of the intervention (thalassotherapy including airfare and lodging), or sic885 per patient based on a more realistic cost estimate. Conclusions. The temporary improvement in quality of life due to an adjuvant treatment course of spa therapy for patients with FM is associated with limited incremental costs per patient.