Global, regional, and national burden of osteoarthritis, 1990–2020 and projections to 2050

Abstract

Background

Osteoarthritis is the most common form of arthritis in adults, characterised by chronic pain and loss of mobility. It most frequently occurs after age 40 and prevalence increases steeply with age. The World Health Organization has designated 2021–2030 the “Decade of Healthy Ageing”, which highlights the need to address diseases such as osteoarthritis that strongly affect functional ability and quality of life. Osteoarthritis can co-exist with, and negatively impact, other chronic conditions. Here we estimate the burden of hand, hip, knee, and other sites of osteoarthritis across geographies, age, sex, and time, with forecasts of prevalence to 2050.

Methods

Osteoarthritis prevalence in 204 countries and territories for 1990–2020 was estimated using data from population-based surveys from 26 countries for knee osteoarthritis, 23 countries for hip osteoarthritis, 42 countries for hand osteoarthritis, and USA insurance claims for each of the osteoarthritis sites, including the residual, other osteoarthritis category. The reference case definition was symptomatic, radiographically confirmed osteoarthritis. Studies using alternative definitions from the reference case definition (for example, self-reported osteoarthritis) were adjusted to reference using regression models. Osteoarthritis severity distribution was obtained from a pooled meta-analysis of sources using the Western Ontario and McMaster Universities Arthritis Index. Final prevalence estimates were multiplied by disability weights to calculate years lived with disability (YLDs). Prevalence was forecast to 2050 using a mixed effects model.

Findings

Globally, 595 million (95% uncertainty interval 535–656) people had osteoarthritis in 2020, equalling 7.6% (6.8–8.4) of the global population, and an increase of 132.2% 130.3–134.1) in total cases since 1990. Compared to 2020, cases for osteoarthritis are projected to increase 74.9% (59.4–89.9) for knee, 48.6% (35.9–67.1) for hand, 78.6% (57.7–105.3) for hip, and 95.1% (68.1–135.0) for other osteoarthritis by 2050. The global age-standardised rate of YLDs for total osteoarthritis was 255.0 YLDs (119.7–557.2) per 100,000 in 2020, a 9.5% (8.6–10.1) increase from 1990 (233.0 YLDs [109.3–510.8] per 100,000). For adults aged 70 years and older, osteoarthritis was the seventh ranked cause of YLDs. Age-standardised prevalence in 2020 was over 5.5% in all world regions, ranging from 5677.4 [5029.8-6318.1] per 100,000 in southeast Asia to 8632.7 [7852.0-9469.1] per 100,000 in high-income Asia Pacific. Knee was the most common site. High body-mass index (BMI) contributed to 20.4% (95% UI –1.7–36.6) of osteoarthritis. Potentially modifiable risk factors for OA such as recreational injury prevention and occupational hazards have not yet been explored in GBD modelling.

Interpretation

Osteoarthritis age-standardised YLD rates are continuing to rise and will lead to substantial increases in case numbers due to population growth and ageing and the lack of an effective cure for OA. The demand on health systems for care such as joint replacements, highly effective for late stage OA in hips and knees, will rise in all regions but may be out of reach and lead to further health inequity for individuals and countries unable to afford them. Much more can and should be done to prevent people getting to that late stage.  

Funding

Bill and Melinda Gates Foundation, Institute of Bone and Joint Research (IBJR), Global Alliance for Musculoskeletal Health (GMUSC), Commonwealth Govt Australia.