Close to one in two cases of dementia could be preventable in low- to middle-income countries, a UCL study has found.
The findings, published in Lancet Global Health, showed how improving childhood education and other health outcomes throughout life could reduce the risk of dementia.
“After our previous research finding that one in three cases of dementia could be preventable, we realised that the evidence was skewed towards higher-income countries,” said the study’s lead author, Dr Naaheed Mukadam (UCL Psychiatry).
“We have now found that in low- to middle-income countries in Asia and Latin America, dementia may be even more preventable than it is in more wealthy countries. If life-course risk factors such as low levels education in early life and hearing loss, obesity and low physical activity in mid-life to old age are addressed, these countries could see large improvements in their dementia rates.”
The research team built on their previous work for the Lancet Commission on dementia prevention, intervention, and care, published in 2017, which found that 35% of dementia is attributable to nine risk factors: low levels of childhood education, hearing loss, smoking, hypertension, obesity, physical inactivity, social isolation, depression, and diabetes.
To understand whether the commission’s findings would apply equally to global regions that were underrepresented in the report, a team of UCL researchers sought out data from China, India and Latin America. They drew from the research collective 10/66 Dementia Research Group’s data, which used similar methodology to gauge prevalence of the nine risk factors in those countries, with sample sizes of 1,000 to 3,000 in each country.
The researchers found even more potential for preventing dementia across the globe, as the proportion of dementia linked to the nine modifiable risk factors was 40% in China, 41% in India and 56% in Latin America.
A major factor in that difference is the lower levels of educational attainment in low- to middle-income countries, which the researchers say signals hope for the future, as educational levels rise.
“People growing up in Asia and Latin America today are more likely to have completed schooling than their parents and grandparents were, meaning they should be less at risk of dementia later in life than people who are already over 65. Continuing to improve access to education could reap great benefits for dementia rates in years to come,” Dr Mukadam said.
