A 2023 study by University College London(UCL) suggests that up to 1.7 million individuals could be living with dementia in England and Wales by 2040, representing a more than 40% increase from previous forecasts. As of February 29, 2024, there were 478,822 patients with recorded diagnoses of dementia according to the NHS.
Additionally, as of 2022, approximately 3% of individuals with dementia come from BAME (Black, Asian, and Minority Ethnic) communities, totalling around 25,000 people. This figure is projected to double by 2026, with the most significant rise anticipated within South Asian communities. Studies indicate that BAME communities frequently encounter delays in dementia diagnosis and encounter obstacles when attempting to access services.
This emphasises the growing importance of prevention, diagnosis, support, and quality of life initiatives for those affected by dementia and working towards that very goal, two leading research teams are set to conduct nationwide trials to develop accurate and rapid blood tests for diagnosing dementia, aiming to address the UK's alarmingly low diagnosis rate.
UCL and Dementias Platform UK, based at the University of Oxford, will leverage recent breakthroughs in potential dementia blood tests and gather evidence for their validation within the NHS within the next five years.
Funded by a multi-million-pound award from Alzheimer’s Society, Alzheimer’s Research UK, the National Institute for Health and Care Research, and Gates Ventures, including contributions from players of People’s Postcode Lottery, the initiative known as the Blood Biomarker Challenge seeks to transform dementia diagnosis.
Blood tests can help overcome current limitations
Dementia is currently diagnosed using memory and thinking tests as well as scans that look at the structure of the brain. According to Katherine Gray, Head of Research at Alzheimer’s Society, “These tests do not show the proteins that are building up in the brain, leading to the need for more advanced techniques. Two ways we can detect these proteins are through specialised brain scans (called Positron Emission Tomography or PET scans) or by measuring them in spinal fluid. However, both methods require a specialised workforce and equipment and are expensive and invasive. They are also not widely available.”
Dr Ashvini Keshavan, who will be leading the ADAPT team of research alongside Professor Jonathan Schott at University College London also provides insight into this by highlighting that, according to the typical evaluation conducted in many memory clinics, there is approximately a 30% probability of receiving an incorrect diagnosis of Alzheimer's disease. She also remarks that both the PET scans and the measurement of cerebrospinal fluid (CSF), apart from being available to a limited 2% of people attending memory clinics, are also impractical to roll out to the hundreds of thousands of people being assessed in memory clinics each year.
She said, “Evidence suggests that, at least in specialist centres, the best blood tests are at least 90-95% as accurate as PET or CSF measures. We plan to assess whether the performance of these tests in the real world will be similar and whether they will be cost-effective. Importantly they will not be an alternative to current diagnostic methods but a tool to be added to them.”
Katherine further underscored the importance of blood testing given the fact that it is an inexpensive way to detect the diseases that cause dementia early and accurately. She said, “This is crucial as it allows people to access the care and support they need, and plan for their future. New treatments are being developed, such as lecanemab and donanemab, which appear to slow disease progression in people with early Alzheimer’s disease. Therefore, for people to be eligible to receive them, they need an accurate and early diagnosis. Research into blood-based biomarkers will also allow us to understand the diseases better, including their causes and processes that are happening in the body.”
Dementia affects the South Asian community disproportionately
Dr Mohammed Akhlak Rauf MBE, the Founder and Director of Meri Yaadain CiC, a non-profit organisation situated in West Yorkshire, has been dedicated to aiding South Asian communities affected by dementia, as well as family caregivers, through the provision of information, awareness initiatives, and advocacy efforts since 2006.
According to him, dementia diagnosis rates amongst South Asian communities may be low as the data collected on ethnicity is fairly recent. He said, “Somewhere between 20-25,000 South Asians in the UK are indicated to be living with dementia. Of course, that would also mean many more are affected by dementia as family carers, partners etc.”
Highlighting the barriers faced by people with dementia in the South Asian community, he points out that there is no word for dementia in the main South Asian languages and that means many people are oblivious to the condition. Highlighting more barriers, he said, “Some people do not go to the GP because they are scared that they will be seen to be going crazy, putting pressure on themselves and their families. Family members struggle to understand why the relative is becoming strange. This is hugely why South Asian people report dementia symptoms later rather than at earlier stages.”
Dr Rauf also feels that while the blood tests may well be helpful, there is an issue of people in the South Asian communities understanding the role of research and what getting involved means for them. He believes that recruiters need to highlight these communities in their recruitment strategies. “People in minoritised ethnic communities want to see posters that have people who look like them, perhaps some of the advertisements are in Asian media and press. The inclusion of main South Asian languages would also be helpful as this demonstrates that the researchers are actively trying to reach out to otherwise sceptical or underserved communities.”
Adding to this disproportionate effect of dementia, Dr Keshavan revealed recent research indicating that South Asians are younger at dementia diagnosis and survive for a shorter time after diagnosis than White individuals, suggesting overall that by the time they are diagnosed, they have more severe illness. Explaining further she said, “The reasons for this are unknown and many factors may contribute. However, we must aim to reduce inequalities of access to accurate diagnosis as much as we can. Blood tests might do this by widening access to populations outside of those served by academic centres, thus ensuring that they get the right care and support earlier in their illness.”
Katherine seconds Dr Rauf’s suggestions and Dr Keshavan’s opinion, stating, “People from ethnic minority backgrounds are often underrepresented in research. Part of the work of the Blood Biomarker Challenge is to make sure that the blood tests work, and the results can be interpreted correctly for everyone. The project will look at how test results vary between people based on their ethnicity, age and gender.
“Those involved in the Blood Biomarker Challenge could be part of a significant moment in history, changing how dementia is diagnosed and treated, which could have a huge impact on thousands of lives and we want to encourage people from all ethnic backgrounds to take part in the project.”
Hope for Parkinson’s Disease?
Professor K. Ray Chaudhuri is Professor of Neurology/Movement Disorders at King’s College Hospital (KCH) and Director of the Parkinson Foundation International Centre of Excellence at King’s College. He expresses that the concern around the effect of dementia can also be extended to Parkinson's Disease(PD), the fastest-growing neurodegenerative condition in the world that can also lead to dementia (in some subjects). “Although it is far too early to comment on this with any certainty, these blood tests may have a value for Parkinson's as well”, he said.
He further sounds caution, stating, “We must not forget that many of us have a build-up of these proteins in the brain and may not develop dementia in our lifetimes. So a single blood test cannot be the answer. In both Alzheimer’s Disease and Parkinson’s Disease in future, if blood tests are used to predict diagnosis this must be supported by educative bespoke counselling as well as other tests, so that prediction can be made with confidence and importantly a wrong diagnosis is not given.”
