Encouraging population attributable factors including childhood education and other health outcomes could greatly help alleviate dementia in low to middle income countries like India, China and Latin America when compared to high income countries, reported a recent study led by University College London.
The findings, published in The Lancet Global Health, stressed on the potentially modifiable risk factors leading to dementia based on high and low income countries.
In their previous study the researchers found that the risk of dementia was attributable to nine potentially modifiable population attributable fractions (PAFs) . These risk factors involved less childhood education, early loss of hearing, hypertension, obesity, later-life smoking, depression, physical inactivity, social isolation, and diabetes accounting for 35% of worldwide dementia. The study was published in The Lancet Commision on “Dementia prevention, intervention, and care”in 2017. However most data used to calculate these risk factors mostly came from high-income countries alone.
“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, Psychiatrist at University College London, in the press release.
Inorder to understand whether the findings would apply equally to global regions, the current study sought out data from low to middle income countries including China, India and Latin America (LMICs).
The study analysed the data obtained from the 10/66 Dementia Research surveys of representative populations in India, China, and six Latin America countries with sample sizes of 1,000 to 3,000 in each country.The study was equally aimed at identifying potential dementia prevention targets in these countries.
The findings revealed a prevalence of 5 of the potentially modifiable risk factors involving less early education, smoking, hypertension, obesity and diabetes in these countries. The data showed that targeting these risk factors as part of dementia prevention strategy could potentially improve the outcome in these countries.
The overall population attributable fractions for dementia accounted for 40% in China, 41% in India, and 55·8% in Latin American sample.
Social isolation is a major risk factor of dementia in higher income countries, but much less so in countries like China and Latin America. The researchers reveal that it is important to build more connected communities to mitigate against the dementia risk tied to social isolation.
Obesity and hearing loss in mid-life, and low physical activity in later life, were also strongly linked to dementia risk in the study area. Mid-life hypertension attributed to dementia more in China and Latin America while it was late-life smoking in India.
“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 of 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.”said Dr. Mukadam.
“While we don’t expect these risk factors to be eliminated entirely, even modest improvements could have immense impact on dementia rates. Delaying the onset of dementia by just five years would halve its prevalence,” said senior author Professor Gill Livingston Psychiatrist UCL.