Burden of Knee Osteoarthritis in 204 Countries and Territories, 1990–2019: Results From the Global Burden of Disease Study 2019

To report the global, regional, and national estimates of knee osteoarthritis (OA) burden and associated risk factors (high body mass index [BMI]) by age, sex, and sociodemographic index (SDI) for 204 countries from 1990 to 2019.We analyzed the prevalence, incidence, years lived with disability (YLDs), and age-standardized rates of knee OA using data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019. Estimates of the knee OA burden were derived from data modeled using a Bayesian meta-regression analytical tool (DisMod-MR 2.1).The global prevalence of knee OA in 2019 was ~364.6 million (95% uncertainty interval [95% UI] 315.3 to 417.4). The age-standardized prevalence in 2019 was 4,376.0 per 100,000 (95% UI 3,793.0 to 5,004.9), an increase of 7.5% between 1990 and 2019. There were ~29.5 million incident cases of knee OA in 2019 (95% UI 25.6 to 33.7), with an age-standardized incidence of 350.3 per 100,000 (95% UI 303.4 to 398.9). The global age-standardized YLD resulting from knee OA was 138.2 (95% UI 68.5 to 281.3) per 100,000 population in 2019, an increase of 7.8% (95% UI 7.1 to 8.4) from 1990. Globally in 2019, 22.4% (95% UI 12.1 to 34.2) of YLD resulting from knee OA was attributable to high BMI, an increase of 40.5% since 1990.The prevalence, incidence, YLDs, and age-standardized rates of knee OA increased substantially in most countries and regions from 1990 to 2019. Continuous monitoring of this burden is important for establishing appropriate public prevention policies and raising public awareness, especially in high- and high-middle SDI regions.