Study: Global Dementia Seen Tripling by 2050 Unless Countries Address Risk Factors

Analysis examines the impacted of expected trends in exposure to high blood sugar, low education levels, obesity, and smoking.

The number of individuals aged 40 years or older worldwide living with dementia is expected to nearly triple in 2050 to an estimated 153 million from an estimated 57 million in 2019, because of aging and population growth, the results of a new study show.

The Global Burden of Disease study, published in The Lancet Public Health, is the first to provide forecasting estimates for 204 countries.

Investigators examined 4 different risk factors for dementia and highlighted the impact these factors will have on future trends. The risk factors are high blood sugar, low levels of education, obesity.

One of the findings suggests that improvements in global education access are projected to reduce dementia prevalence by 6.2 million cases worldwide by 2050. However, this would be countered by anticipated trends in high blood sugar, obesity, and smoking, which are expected to result in an additional 6.8 million dementia cases.

“Our study offers improved forecasts for dementia on a global scale, as well as the country level, giving policy makers and public health experts new insights to understand the drivers of these increases based on the best available data, Emma Nichols, PhD, from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, said in a statement. “These estimates can be used by national governments to make sure resources and support are available for individuals, caregivers, and health systems globally.”.

The investigators predict that the greatest increase in prevalence will occur in eastern sub-Saharan Africa, where the number of individuals with dementia is expected to rise by 357% to more than 3 million in 2050 from nearly 660,000 in 2019, with Djibouti (473%), Ethiopia (443%), and South Sudan (396%) seeing the greatest increases.

Additionally, in the Middle East and north Africa and the Middle East, cases are predicted to grow by 367% to nearly 14 million from almost 3 million individuals, with the largest increases being in Qatar (1926%), the United Arab Emirates (1795%), and Bahrain (1084%).

In western Europe, the number of dementia cases is expected to rise by 74% to nearly 14 million in 2050 from almost 8 million in 2019. Relatively small increases in cases are expected in Greece (45%), Italy (56%), Finland (58%), Sweden (62%), and Germany (65%). The number of cases in the United Kingdom is expected increase by 75% to almost 1.6 million in 2050 from just over 907,000 cases in 2019.

By contrast, the smallest increase in the number of dementia cases is projected in high-income Asia Pacific, where the number of cases is expected to grow by 53% to 7.4 million in 2050 from 4.8 million in 2019 to 7·4 million in 2050, with a particularly small increase in Japan (27%). In this region, the risk of dementia for each age group is expected to fall, suggesting that preventive measures, including improvements in education and healthy lifestyles are having an impact.

Globally, women with dementia outnumbered men with dementia in 2019, 100 to 69, and this pattern is expected to remain in 2050, according to the analysis.

The investigators acknowledged that their analysis was limited by a lack of high-quality data in serval parts of the world, including Central America, eastern Europe, and sub-Saharan Africa and by studies using different methodologies and definitions of dementia.

They also acknowledged that they were unable to consider all 12 risk factors from the 2020 Lancet Commission Report, because of limited risk factors in the study and only included the risk factors with strong evidence of association.

Reference

The Lancet Public Health: global dementia cases set to triple by 2050 unless countries address risk factors. EurekAlert. News release. January 6, 2022. Accessed January 10, 2022. https://www.eurekalert.org/news-releases/939299