The importance of patients' beliefs about biologic therapy in axial spondyloarthritis

To investigate the impact of beliefs about biologic therapy on treatment response and to identify the factors associated with treatment beliefs in patients with axial spondyloarthritis (axSpA).

A total of 137 axSpA patients (62% male; mean age, 41.1 ± 12.1 years) initiating or switching biologic therapy participated in this observational study. Patients' beliefs about biologic treatment were assessed using the Beliefs about Medicines Questionnaire (BMQ) at baseline and at 12 and 24 months. Treatment responses were evaluated using the Axial Spondyloarthritis Disease Activity Score - Clinically Important Improvement (ASDAS-CII) and the Bath Ankylosing Spondylitis Disease Activity Index 20 (BASDAI20). Associations between BMQ scores, treatment response, and related factors were analyzed using generalized estimating equations (GEE).

BMQ-specific Concern scores were consistently lower than BMQ-specific Necessity scores. Although beliefs regarding Necessity and Harm did not change significantly over time, beliefs about Concern and Overuse did change, leading to an increase in the necessity - concern differential (NCD). Treatment response and biologic discontinuation were not significantly associated with BMQ scores in the longitudinal analyses. Multivariable GEE analyses revealed that Necessity beliefs were associated with enthesitis, dactylitis, and uveitis. Concern scores were predicted by peripheral arthritis, inflammatory bowel disease, and disease activity, while uveitis also influenced NCD, Overuse, and Harm beliefs. Dactylitis and older age were associated with increased Overuse and Harm scores. Additionally, both psoriasis and DMARD use were linked to higher Harm perceptions. The functional index was not a significant predictor in any model.

In this longitudinal analysis, the beliefs of axSpA patients about treatment varied significantly depending on their perceived treatment benefits and experience with biologic therapy. Furthermore, specific disease manifestations were shown to influence treatment-related beliefs.