Helping to diagnose more people with dementia
In the UK, around 900,000 people live with dementia – a number that is expected to rise sharply in the coming years. Early detection and prompt treatment could help delay the onset of dementia, helping people live longer in good health.
Scientists believe that ethnicity may affect dementia risk because of its impact on other risk factors like vascular diseases, access to health services, racism and socioeconomic deprivation.
Historically, studies into dementia have underrepresented people from ethnic minority backgrounds and areas where people face more financial hardship. We need a better understanding of the risk of dementia in more diverse populations, to develop ways to help everyone affected by the condition.
That’s why, in 2017, we awarded £1.5 million to establish a Preventive Neurology Unit (PNU) at the Wolfson Institute of Population Health, Queen Mary University, to research brain and nervous system disorders.
Dr Charles Marshall is a consultant neurologist and dementia expert at Barts Health NHS Trust and leads a programme of dementia research at the PNU. His team recently conducted the first dementia study to adequately represent a diverse UK population, involving more than a million people across East London.
They found that both ethnicity and socioeconomic deprivation are much more important risk factors for dementia than previously thought. This highlights the need to prioritise preventing dementia in these populations. The findings are now influencing the commissioning of dementia services in East London.
This is the process by which the NHS plans, agrees and monitors its services. This will help to address local healthcare inequalities so that people can get the care they need. Our investment in the PNU has allowed Dr Marshall to develop a new cognitive neurology service at Barts Health.
Dr Marshall also works as a consultant at the East London Foundation Trust Diagnostic Memory Clinic in Tower Hamlets. This brings specialist dementia diagnoses to a population that didn’t have access to these important services before.
Dementia research findings: a link to ethnicity and socioeconomic deprivation
The study found around 1 in 10 cases of dementia were linked to ethnicity, and a similar number to socioeconomic deprivation (population attributable risks of 9.7% and 11.7% respectively) – even after adjusting for modifiable risk factors like smoking, weight and vascular health. Stressful and traumatic life events have been linked to dementia, so it’s thought that issues like racism and poverty-induced stress could play a role in raising the risk of the disease among these groups.
Black and South Asian people were more likely to develop dementia than their White counterparts (odds ratios of 1.43 and 1.17 respectively) and were likely to be diagnosed at an earlier age (0.7 and 0.55 respectively). People living in more socioeconomically deprived areas also faced higher risks, with dementia twice as common in the poorest group compared with the most affluent (based on 10 deciles in the English indices of deprivation).
Researchers acknowledge the study is limited by lack of data on some dementia risk factors, such as education and air pollution. However, studying a single geographical region is likely to have reduced any confusion by environmental factors; it’s also unlikely that education could explain the difference in dementia cases, as research has only found this to be a risk factor when people have no secondary education at all, which is only the case for 0.2% of UK adults.
"This research highlights a need to prioritise dementia prevention strategies in diverse and deprived populations."Dr. Charles Marshall, Honorary Consultant Neurologist at Queen Mary University of London
Reflecting on this research
Phazha Bothongo, who led the study at Queen Mary’s Wolfson Institute of Population Health, explained, “These results show that ethnicity and area deprivation in East London are independently associated with dementia – and, crucially, this effect may not be attributable to other risk factors. Further study is needed to unpick the underlying mechanisms by which ethnicity and deprivation confer this increased risk of dementia, so that efforts to prevent the disease can be applied across ethnic and socioeconomic boundaries.”
Dr. Charles Marshall, Honorary Consultant Neurologist at Queen Mary University and senior author of the study, continued, “This research highlights a need to prioritise dementia prevention strategies in diverse and deprived populations, where previously the focus has been on modifiable risk factors. Our findings suggest there may be relatively modest benefits in targeting established modifiable risk factors, but we could potentially prevent a greater proportion of cases by targeting any modifiable factors underlying the increased risk attributable to ethnicity and deprivation.”