Objectives: This study aimed to investigate global, regional, and national trends in osteoarthritis disability-adjusted life years (DALYs) from 1990 to 2019, identify the burden of osteoarthritis in different age groups, and assess age, period, and cohort effects on osteoarthritis DALYs.

Study design: A comprehensive analysis of the Global Burden of Disease Study 2019 data, covering 204 countries and territories.

Methods: We conducted a comprehensive analysis using data from the Global Burden of Disease Study 2019, encompassing 204 countries and territories. Age-standardized DALY rates were calculated, and the age-period-cohort model was employed to examine the age, period, and cohort effects on osteoarthritis DALYs. The annual percentage change (APC) and average annual percentage change (AAPC) were estimated to evaluate trends in DALYs.

Results: Globally, osteoarthritis DALYs increased by 114.48 % between 1990 and 2019, with an age-standardized DALY rate growth of 3.3 %. The largest relative growth in DALYs occurred in Middle and Low-middle Socio-Demographic Index (SDI) regions. DALYs increased significantly in almost all age-specific groups, particularly among 45-74 years old age groups. Age, period, and cohort effects analysis revealed a general increase in osteoarthritis DALYs risk over time, with some variations by SDI quintiles and sex. The steepest increase in DALYs occurred in the 30-34 years age group, and the trend attenuated with increasing age. Males showed significantly slower DALYs growth than females in age groups with non-overlapping 95 % confidence intervals. Age effects were consistently higher in females, especially in high-SDI countries. Period and cohort effects generally demonstrated a climbing risk of osteoarthritis DALYs across different SDI quintiles, with more pronounced increases in lower-SDI regions.

Conclusions: Our findings highlight the substantial and increasing burden of osteoarthritis at global, regional, and national levels from 1990 to 2019, with significant variations by age, period, and cohort. These results underscore the importance of developing targeted public health strategies and interventions to address the growing impact of osteoarthritis, particularly in lower-SDI regions and among older populations.