Exercise is medicine: longstanding exercise therapy in people with axial spondyloarthritis and severe functional limitations

Axial Spondyloarthritis (axSpA) is a chronic, inflammatory, rheumatic disease that leads in many patients to significant functional limitations. Exercise therapy is a key element of the management axSpA, based its proven effectiveness and safety. However, most studies on exercise therapy have focused on people with mild symptoms, excluding those with severe limitations due to high disease activity, joint damage, or comorbidities. This thesis includes a randomized, controlled, multicenter trial evaluating the effectiveness and cost-effectiveness of a personalized, supervised exercise intervention for people with axSpA and severe functional limitations as compared to usual care. The intervention, delivered by trained primary care physical therapists, was found to have a statistically significant effect on physical function and physical quality of life, at slightly higher costs, the latter indicating that there are no economic reasons to refrain from the national implementation of the intervention. In addition, this thesis addresses the current delivery of physical therapy in people with rheumatic diseases, the use of wearable activity trackers to improve physical activity and the construct validity of the Patient-Reported Outcome Measurement Information System (PROMIS) Physical Functioning 10-item questionnaire, an instrument to evaluate physical functioning in people with inflammatory rheumatic diseases. <br>