A person’s risk of developing dementia could depend on their ethnicity, a study has suggested.
Researchers said conditions such as diabetes, obesity and high blood pressure – which are all risk factors of dementia – are “magnified” among some ethnic groups.
Experts called for more work on how people from different ethnicities may be able to stave off dementia.
A team led by Naaheed Mukadam of University College London looked at the relationship between the risk factors and dementia onset using English primary care records for 865,674 adults in diverse ethnic groups from 1997 to 2018.
According to the NHS, more than 944,000 people in the UK have dementia.
It is estimated by 2030, the number of people living with the disease will top one million.
The research team found 12.6% of the cohort developed dementia.
Some 16% were white, 8.6% were South Asian, 12.1% were black and 9.7% were from different ethnic groups.
They assessed risk factors associated with dementia among the patients, including obesity, diabetes, sleep disorders, high blood pressure and dyslipidemia – an imbalance of lipids that can cause heart disease.
High blood pressure was associated with a higher risk of dementia in black people compared to white people, while South Asian people were more likely to develop dementia as a result of sleep disorders, diabetes, low HDL cholesterol and high blood pressure.
We need tailored dementia prevention, taking into account ethnicity and risk factor profile to ensure dementia prevention is equitable.— Study authors
Compared to white patients, researchers said high blood pressure has 1.57 times more impact on dementia risk in South Asians and 1.18 times more impact in black people.
The team said their findings – published in Plos One – could explain “previous findings of greater susceptibility, earlier age of dementia onset, and shorter survival after dementia diagnosis in minority ethnic groups”.
The authors added: “We found that not only are some risk factors for dementia more common in minority ethnic groups but that the impact of some of these risk factors is even greater than in the white population.
“So we need tailored dementia prevention, taking into account ethnicity and risk factor profile to ensure dementia prevention is equitable.”
The study was funded by Alzheimer’s Society. The charity’s associate director for research and innovation, Dr Richard Oakley, said: “We know that dementia, and dementia risk, affects people differently based on a number of factors, including hypertension, obesity and diabetes.
“Previous research shows that these health conditions are more common in people from South Asian and African Caribbean backgrounds – this Alzheimer’s Society-funded research builds on this evidence, suggesting that these risk factors are also more likely to put people at increased risk of developing dementia than if they are white.
“This study is important, particularly as it looked at data from a larger and more representative number of people, unlike previous studies. What we now need to look into is why certain health conditions are more prevalent in certain communities than others and why the impact of these factors on someone’s risk of developing dementia are stronger.
“We also need to see dementia prevention and diagnosis services in place that are designed to best support people from all backgrounds.
“Research will beat dementia and with dementia being the UK’s biggest killer, and one in three people born today going to develop the condition, research has never been more important.”
David Thomas, head of policy at Alzheimer’s Research UK, said: “It’s a shocking truth that people from ethnic minorities face an increased risk of a number of health conditions, and this impacts their ability to live a healthy life.
“Recent research has shown that dementia is no exception – people from South Asian and black communities appear to be more likely to die from dementia, and at a younger age too.
“These latest findings suggest one reason why: the impact of risk factors like high blood pressure in increasing an individual’s risk of dementia appears greater in both South Asian and black communities.
“It will be important to understand why this effect is greater, as doing so would open up an enormous opportunity to reduce the personal and societal impact of this heart-breaking condition on people from black and South Asian communities.
“But this is not just a public health problem, it is a political problem too. We need a national cross-government prevention strategy that tackles health inequalities.
“This needs proper funding, and must encourage better joint working across all Government departments to truly break the link between an individual’s background and their prospects for a healthy life, including dementia risk.”
