Temporal trends and projections of the global burden of osteoarthritis derived from the Global Burden of Disease 2021 study

Background: This study updates the assessment of the global, regional, and national burden of osteoarthritis (OA) from 1990 to 2021, focusing on trends in incidence, prevalence, and years lived with disability (YLDs), and explores the sociodemographic factors influencing these trends. Methods: Data from the Global Burden of Disease Study 2021 were used to estimate OA incidence, prevalence, and YLDs at global, regional, and national levels. Joinpoint regression analysis was employed to assess temporal trends, while age-period-cohort models were used to examine the effects of age, period, and birth cohort on OA trends. The Slope Index of Inequality and Concentration Index were applied to analyze cross-country health inequities in OA burden. Results: Between 1990 and 2021, the global OA case count increased from 20.9 million to 46.6 million (122.7%), with the ASIR (age-standardized incidence rate rising) from 489.78 to 535 per 100,000 (9.25%; EAPC(estimated annual percentage change): 0.33, 95% CI: 0.31–0.35). Global prevalence increased from 256 million to 606 million cases, with ASPR (age-standardized prevalence rates) rising from 6393.12 to 6967.29 per 100,000. Regionally, low SDI (sociodemographic index) regions exhibited a 156.23% increase in incidence compared to 73.26% in high SDI regions. At the country level, China’s OA cases increased by 150.38% (ASIR: 487.11 to 554.61 per 100,000; EAPC: 0.58, 95% CI: 0.51–0.66). The BAPC model forecasts an ASIR of approximately 535 per 100,000 by 2030. Conclusion: The burden of OA has significantly increased over the past three decades, with notable regional disparities. This rise is primarily attributed to population aging and increasing obesity rates. Targeted prevention, early diagnosis, and enhancements in healthcare services are crucial to addressing the growing global impact of OA.