Introduction
Clinical practice guidelines (CPGs) are instrumental in standardizing evidence-based diagnostic and treatment protocols in rheumatology [1]. However, the integrity of these guidelines can be compromised by conflicts of interest (COIs), both financial and non-financial [2-4]. Indeed, over the last two decades, several violations of patient-centered care by clinical practice guidelines, as well as harmful effects on patients [4,5], have resulted in the establishment of more stringent COI management policies through global collaborations [1,6,7]. Given the increasing influence of CPGs on patients, healthcare professionals, and other stakeholders, rigorous COI management—including full disclosure of COIs, efforts to minimize COIs among CPG authors and organizations, and balanced recommendations by multiple experts—is essential for establishing trustworthy CPGs and promoting patient-centered care [6-12].
Over the past 30 years since the first introduction of methotrexate for rheumatoid arthritis treatment, there has been remarkable development in systematic treatment strategies for rheumatoid arthritis [13]. In addition, the success of the first biologic therapy, namely tumor necrosis factor (TNF) inhibitors, has provided further impetus for the development of other biologics targeting different pathways such as IL-1 inhibitors, IL-6 inhibitors, IL-17 inhibitors, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) blockers, and Janus Kinase (JAK) inhibitors [14]. Due to fierce competition among pharmaceutical companies, the global market for rheumatoid arthritis was expected to be worth approximately US$26 billion in 2019 and the pharmaceutical companies have increasingly marketed their products to physicians involved in treating and managing patients with rheumatoid arthritis [15-17]. Given these contexts, authors of rheumatoid arthritis CPG should properly manage their COI with pharmaceutical companies. This study aimed to assess the financial relationships between pharmaceutical companies and CPG authors using publicly disclosed payment data in Japan.