Global 130%+ rise in postmenopausal osteoarthritis and associated disability over past 3 decades

The global number of cases of osteoarthritis, as well the disability associated with the condition, have risen by more than 130% over the past 3 decades among women who have gone through the menopause, indicates a data analysis spanning 1990 to 2021, and published in the open access journal BMJ Global Health.

During this period, East Asia and high income Asia Pacific countries experienced the fastest growth in the condition while excess weight accounted for 20% of the total years lived with the resulting disability, the analysis indicates.

Osteoarthritis is primarily characterised by the deterioration and damage of joint cartilage, accompanied by bony remodelling, joint dysfunction, and chronic pain.

In 2020 alone, an estimated 595 million people worldwide were living with the condition, comprising nearly 8% of the world’s population, with postmenopausal women at heightened risk. 

To better understand the global impact of osteoarthritis in this group, the researchers drew on The Global Burden of Disease (GBD) 2021 study. This collected and analysed data from 204 countries and territories for the prevalence, severity, and deaths attributable to 371 diseases between 1990 and 2021. 

The researchers focused in particular on rates of new and existing cases of knee, hip, hand, and ‘other’ osteoarthritis and years of healthy life lost (DALYs) among postmenopausal women, aged 55 and above. 

The menopause signals a decline in oestrogen levels, which not only affects skeletal health, but is also directly linked to the function and stability of the joint system, explain the researchers.

The GBD framework incorporates the SocioDemographic Index (SDI), a composite measure of a nation’s development, based on income per head of the population, average years of education, and fertility rates for those under 25.

And to provide regional estimates of osteoarthritis, these countries and territories were further divided into 21 regions, based on geographic proximity and cultural similarities. 

Generally, global age standardised rates of new and existing cases and DALYs for all types of osteoarthritis steadily increased in postmenopausal women across all age groups from 1990 to 2021.

In 2021 there were 14,258,581 new cases; 278,568,950 existing cases; and 99,447,16 DALYs, representing increases of 133%, 140%, and 142% since 1990, respectively.

High SDI areas exhibited significantly greater incidence, prevalence, and DALY rates than other regions, with the exception of other osteoarthritis. 

Osteoarthritis of the knee was the most common type and associated with the highest loss of healthy years of life (1264.48/100,000 people), followed by that of the hand and ‘other’. 

At the other end of the spectrum, osteoarthritis of the hip was the least common and associated with the lowest rates of DALYs.

Among the 21 GBD regions, high income Asia Pacific countries had the highest age standardised incidence, prevalence, and DALY rates for knee osteoarthritis per 100,000 people, while countries in Central Asia reported the lowest age standardised rates.

The fastest rise in new cases of knee osteoarthritis occurred in Southeast Asia while the most rapid rise in prevalence and DALYs occurred in East Asia. 

The highest burden of hand osteoarthritis was in Central Asia while the lowest was in Oceania. The fastest rise in new and existing cases of hand osteoarthritis, as well as DALYs, was observed in East Asia.

All age standardised rates for hip and other osteoarthritis were relatively similar between older men and women of the same age. But women had significantly higher values for hand and knee osteoarthritis than men of the same age. 

Specifically, DALYs  for hand osteoarthritis in 55–59 year old women were nearly twice as high as they were in men of the same age.

Hand and other osteoarthritis showed the fastest growth among 55–59 and 60–64 year old women over the past decade.

Excess weight (BMI), a key risk factor for osteoarthritis, was the only risk factor investigated in the GBD 21 data. It was defined as above 20 to 23 kg/m² for those aged at least 20.

Between 1990 and 2021 DALYs attributable to high BMI among postmenopausal women rose significantly across all SDI categories, and in most regions, with the exception of Central Asia. 

Globally, DALYs attributed to high BMI among postmenopausal women increased from around 17% in 1990 to around 21% in 2021. Regions at the upper end of SDIs had the highest proportions of DALYs associated with high BMI, exceeding 20%, with East Asia showing the sharpest rise from around 14% to 23%. 

Osteoarthritis attributed to high BMI was consistently more of an issue for women in all regions  of the world and across all SDI categories.

The trends observed in East Asia “may be linked to rapid population ageing, increased workforce participation, and a surge in obesity rates due to urbanisation and changing lifestyles,” suggest the researchers.

“Conversely, the high burden observed in high-income Asia Pacific could be attributed to advanced healthcare systems with better diagnostic capabilities, facilitating comprehensive identification and reporting of [osteoarthritis] cases,” they add.

The researchers acknowledge various limitations to their findings including regional variations in data quality, while data from low income countries were often scarce. The age cut-off of 55 may also have excluded women who were postmenopausal at younger ages.

But they conclude: “The burden of [osteoarthritis] among postmenopausal women continues to escalate, highlighting its significant impact on [their] global health.”  

They add: “There is an urgent need for proactive measures to rigorously monitor and manage risk factors, with a particular emphasis on promoting lifestyle adjustments aimed at controlling BMI. Additionally, policies should be implemented that take into account socio-demographic disparities, to effectively alleviate the burden of [osteoarthritis] in postmenopausal women.”