Dynamic Burden of Elderly Knee Osteoarthritis: Global, Regional, and National Analysis (Global Burden of Disease 1990 to 2050)

Background: This study analyzes the disease burden of elderly knee osteoarthritis (KOA) and its risk factors in individuals aged 55+ years using Global Burden of Disease data from 1990 to 2021, aiming to inform public health policy and interventions. Methods: Data from the Global Burden of Disease and Global Health Data Exchange were used to investigate age- and sex-specific trends in KOA incidence, prevalence, and disability-adjusted life years (DALYs). Age-standardized incidence rate (ASIR) and age-standardized disability rate were calculated, and global maps were created to visualize trends. A Bayesian Age-Period-Cohort model predicted the disease burden for 2050. Analyses were done using R software (v4.0.4). Results: From 1990 to 2021, the number of new KOA cases and DALYs increased globally in both men and women, with higher ASIR and DALYs rates in women. ASIR rose across all sociodemographic index (SDI) strata, with the largest increase in low-middle SDI countries. Regionally, ASIR increased in most areas except high-income Asia Pacific. The highest disease burden was observed in the 55 to 59 years age group, with DALYs peaking in the 75 to 79 years age group. At the country level, China, Myanmar, and Malaysia had the highest incidence, whereas China, India, and the United States had the highest DALYs. High body-mass index emerged as a notable contributor to the disease burden in 2021. Projections indicate rising DALYs rates across all age groups by 2050, particularly in the oldest age groups. Discussion: The global burden of elderly KOA has increased markedly over three decades, disproportionately affecting women. ASIR rose across all SDI strata, with the largest increase in low-middle SDI countries. These findings provide evidence for the development of elderly health intervention measures.