Philadelphia, June 16, 2025 – The most comprehensive analysis of rheumatoid arthritis data to date reveals that demographic changes and uneven health infrastructure have exacerbated the rheumatoid arthritis burden since 1980 and shows global disparities on a granular level. The AI-powered study in the Annals of the Rheumatic Diseases , published by Elsevier, utilized deep learning techniques and policy simulations to uncover actionable insights for localized interventions that national-level studies have previously missed. Its design yielded highly precise, dynamic projections of further disease burden to 2040.
Principal investigator Queran Lin, MPH, WHO Collaborating Centre for Public Health Education and Training, Faculty of Medicine, Imperial College London; and Clinical Research Design Division, Clinical Research Centre, Sun Yat-Sen Memorial Hospital, Guangzhou, explains, "While previous Global Burden of Disease (GBD) studies have provided important insights, they have largely focused on high-level descriptions and visualizations at global and national scales, failing to capture local disparities or the dynamic interactions between socioeconomic development and disease trends. With access to sufficient computational resources and advanced analytical capabilities, our Global-to-Local Burden of Disease Collaboration aims to unlock the full potential of the GBD dataset (pioneered by the Institute for Health Metrics and Evaluation, University of Washington). By employing cutting-edge approaches such as transformer-based deep learning models, we were able to generate the most granular disease burden estimates to date, offering a new framework for guiding precision public health across diverse populations."
Using GBD data, the study integrates the largest spatiotemporal rheumatoid arthritis dataset spanning 953 global to local locations from 1980 to 2021 with a novel deep learning framework to reveal how demographic ageing, population growth, and uneven healthcare infrastructure exacerbate rheumatoid arthritis burdens differently across regions. It also enabled investigators to analyze the prevalence, incidence, mortality, disability-adjusted life years (DALYs), years of life lost (YLLs), and years lived with disability (YLDs) of rheumatoid arthritis, as well as their socioeconomic inequalities and achievable disease control based on socioeconomic development level (frontiers) and forecast long-term burdens until 2040 with scenario simulations.
The study observed that globally there were significant absolute and relative sociodemographic index (SDI)-related inequalities, with a disproportionately higher burden shouldered by countries with high and high-middle SDI. Among the key findings of the study are:
- Global rheumatoid arthritis burden increased: From 1980 to 2021, the global rheumatoid arthritis burden kept rising, showing an increase among younger age groups and a wider range of geographic locations worldwide, with hotspots like the UK's West Berkshire (incidence rate: 35.1/100,000) and Mexico's Zacatecas (DALY rate: 112.6/100,000) bearing the highest burdens in 2021 among 652 subnational regions.
- Widening inequalities: DALY-related inequality surged 62.55% from 1990, with Finland, Ireland, and New Zealand as the most unequal countries in 2021.
- Failure to meet frontiers: As SDI increased over time, frontier deviations worsened, which indicated the burden of rheumatoid arthritis has been severely neglected.
- Noneconomic disparities persisted: Economic factors alone are not the sole determinants of rheumatoid arthritis disease burden. High SDI regions such as Japan and the UK exhibited contrasting patterns in disease burden. Japan's declining DALY rates despite high SDI may reflect nationwide early diagnosis programs, widespread use of biologic therapies, and a diet rich in anti-inflammatory components.
- Forecasted increases and need for positive policy: By 2040, low-middle SDI regions may see increasing DALYs due to ageing/population growth, while DALYs in high SDI areas may decrease. Controlling smoking may reduce rheumatoid arthritis deaths by 16.8% and DALYs by 20.6% in high-smoking regions (e.g., China), offering significant benefits for medium/high SDI areas.
Co-lead author Baozhen Huang, PhD, Department of Biomedical Sciences, City University of Hong Kong, says, "Japan's sustained decline in DALYs despite a high SDI proves that socioeconomic status alone doesn't dictate outcomes; proactive healthcare policies such as early diagnosis programs can reverse trends."
Many regions around the world still lack the necessary evidence base to inform precision health policy and targeted interventions. These data are intended to support more informed clinical decisions and health policy planning, especially in settings where reliable subnational evidence has historically been scarce.
Co-lead author Wenyi Jin, MD, PhD, Department of Orthopedics, Renmin Hospital of Wuhan University; and Department of Biomedical Sciences, City University of Hong Kong, concludes, "The adoption of this advanced framework quantifies the expected impact of feasible intervention scenarios in public health, supplying policymakers at global, national, and local levels with more reliable, dynamic evidence, redefining the very paradigm of health surveillance."
