Prevalence of rheumatoid arthritis in China: Variations and trends from the global burden of disease study 2021.

Background and Objectives: The latest prevalence data for rheumatoid arthritis (RA) is essential for effective disease control and management. Although numerous studies examine the global burden of RA, recent data specific to China has been lacking. The aim of this study is to evaluate the variations of RA burden in mainland China from 1990 to 2021 utilizing data from the Global Burden of Diseases, Injuries, and Risk Factors (GBD) study 2021. Methods: We conducted a retrospective analysis of RA burden in China based on the GBD 2021 study. We collected data on RA prevalence, incidence, and disability adjusted life years in China from 1990 to 2021, then calculated the estimated annual percentage change (EAPC) to summarize the overall trends. Results: In 2021, the total numbers of prevalent cases, incident cases, and disability-adjusted life years (DALYs) for RA in China were 4,755,500, 247,300, and 833,800, respectively; From 1990 to 2021, the rates of incidence, prevalence, and DALYs of RA showed an increasing trend, with EAPCs of 0.61, 0.59, and 0.17, respectively. Throughout this period, the RA burden was notably higher in females than in males. In 2021, RA incidence rates among individuals aged 15-44, 45-59, and 60-85+ followed an approximate 1∶1∶1 ratio. Projections using the Bayesian Age-Period-Cohort (BAPC) model indicated that by 2045, compared to 2021, the total incident cases, prevalent cases, and DALYs of RA in China are expected to increase by 15.7%, 13.2%, and 4.2%, respectively. Conclusion: Over the past 32 years, the RA burden in China had continued to increase, and is expected to rise substantially over the next decade. Therefore, it is necessary to strengthen the prevention and management of RA, with priority given to the female population and young patients.