To evaluate the effectiveness of balneotherapy on spondyloarthritis.

Two authors independently searched the CENTRAL, MEDLINE, SCOPUS, EMBASE and WEB OF SCIENCE databases until July 2017, for randomized controlled trials published in French or English, that included participants, and interventions: adults with spondyloarthritis, treated by balneotherapy program or one of its components and compared with any other intervention or no treatment. Internal validity, external validity, quality of the statistical analysis, and publication bias were systematically evaluated. We report the best level of evidence.

Nine articles were selected; the internal validity was high in two studies, average in one study, and low in six studies. With high internal validity, one study found a difference for pain between immersion in radon-rich water and tap water for the whole population or rheumatic disease, but the BASFI is not improved for the subgroup of patients with spondyloarthritis. The other study with high validity reported a significant 28-week improvement in quality of life and a composite index. In a study with moderate internal validity involving ankylosing spondylitis patients with associated with inflammatory bowel disease, a balneotherapy program demonstrated a relevant clinical improvement when compared to patients on waiting list. With low internal validity, TNFa inhibitors+spa therapy were found to be superior to a treatment with TNFa inhibitors alone in patients with psoriatic arthritis.

Two trials with high validity demonstrated improvements, but this systematic review is not sufficient to prove the efficacy of balneotherapy in spondyloarthritis. More trials are needed with larger sample size to confirm the preliminary results observed and conclusively determine the benefits of balneotherapy.