Blood test developed in Cambridge to detect signs of dementia before it develops to be trialled across UK

A blood test to detect the early signs of a type of dementia before it develops will be trialled across the UK in a study led by the University of Cambridge that could improve treatments.

The test, piloted in Cambridge, will measure brain changes in people with dementia as an alternative to much more costly brain scans, which take longer and require specialist equipment not available everywhere.

The trial will focus on frontotemporal dementia - the kind that actor Bruce Willis was diagnosed with in 2023 - but aims to help accelerate the development of treatments for other types of dementia.

It follows research by Dr Maura Malpetti, senior research associate in Cambridge’s Department of Clinical Neurosciences and Race Against Dementia fellow, who found that molecular changes associated with brain inflammation and dementia can also be detected in the blood.

Such changes can be present decades before physical dementia symptoms emerge and are usually only picked up by brain scans.

Dr Malpetti, a bye-fellow at Sydney Sussex College, said: “It’s a very exciting programme because we’re using blood tests to help unlock treatments to slow down the progression of dementia and eventually stop it. It’s also much easier for the patient than a brain scan.

“We’re focusing on changes to the brain which can manifest 10-20 years before symptoms, with the hope that in the future we can treat them early enough to stop the disease before symptoms occur.”

More than 20 research and healthcare centres across the UK will be involved in helping to identify who could benefit most from disease-modifying treatments.

Trials of dementia drugs have typically involved patients who have been diagnosed already and are showing symptoms, by which time it can be too late for the drugs to make an impact.

But identifying individuals decades before symptoms emerge will enable researchers to trial drugs to see if they can reduce the risk of developing dementia.

Around 20,000 people in the UK live with frontotemporal dementia, although it is a rarer type of dementia, meaning it is often misdiagnosed. It causes problems with behaviour, language, and movement and, while dementia mostly affects people over 65, this form tends to start at a younger age, although it can affect older people too.

The study will explore both behavioural variant frontotemporal dementia (bvFTD) and primary progressive aphasia (PPA). The latter is a different clinical syndrome of frontotemporal dementia and unlike other types of dementia, it typically affects speech and language rather than memory.

To recruit patients and raise awareness of the conditions, the Open Network for Frontotemporal dementia Inflammation Research (ON-FIRE) study aims to reach as many areas of the UK as possible, including remote locations often under-represented in clinical studies.

The study will establish a national network and collaborative platform for blood marker discovery in frontotemporal dementia and ‘fingerprint’ inflammatory blood profiles in the condition in people from diverse backgrounds. This will help create an open international resource for research into the diseases, making data and samples available through the Dementias Platform UK (DPUK) and ON-FIRE Biorepository for other researchers.

Higher brain inflammation is associated with faster clinical decline in patients with frontotemporal dementia, as with Alzheimer’s disease, which Dr Malpetti said points to the potential of immunotherapy in treating dementia.

“We want to identify who can benefit most from particular treatments – including families of people who may have genetic forms of dementia – when we need to act, and which parts of the immune system we can target with precision medicine,” she said.

With a large-scale study like ON-FIRE, the hope is researchers can better characterise the processes that play a role in dementia and potentially repurpose existing treatments targeting the mechanisms – a process that is much faster and cheaper than developing new drugs, as their safety profile is already understood.

For her research, Dr Malpetti earned the Race Against Dementia Fellowship in 2021, in partnership with Alzheimer’s Research UK.

The Race Against Dementia charity was established by three-times Formula One World Championship winner Sir Jackie Stewart OBE following his wife Helen’s diagnosis of frontotemporal dementia.

Sir Jackie said: “At Race Against Dementia, our mission is to accelerate the speed of successful dementia research. Dr Malpetti’s groundbreaking work involving a blood test which could detect dementia at a quicker pace, demonstrates our philosophy. Thus by applying the principles of precision, teamwork, and inventiveness from Formula 1 into the world of medical research, we can more efficiently drive progress towards a cure for dementia.”