Scientists detect signs of dementia nine years before diagnosis

Cambridge researchers have shown that it is possible to see signs of brain damage in patients as early as nine years before they are diagnosed with one of a number of dementia-related conditions.

In a study published today in Alzheimer’s disease and dementiathe team analyzed data from the UK Biobank and found impairments in several domains, such as problem solving and number recall, across a range of conditions.

The findings raise the possibility that at-risk patients could be screened in the future to help select those who will benefit from interventions to reduce their risk of developing a disease, or to help identify patients suitable for clinical trials for new treatments. treatment.

Currently, there are very few effective treatments dementia or something else neurodegenerative diseases such as Parkinson’s disease. This is in part because these diseases are often diagnosed only after symptoms appear, while the underlying neurodegeneration can begin years – even decades – earlier. This means that by the time patients take part in clinical trials, it may be too late in the disease process to alter its course.

Until now, it was unclear whether it was possible to detect changes in brain function before symptoms appeared. To help answer this question, researchers from the University of Cambridge and Cambridge University Hospitals NHS Foundation Trust turned to UK Biobank, a biomedical database and research resource containing anonymised genetic, lifestyle and health information from half a million UK participants aged 40 and over. – 69 years old.

As well as collecting information on participants’ health and disease diagnoses, UK Biobank collected data from a range of tests including problem solving, memory, reaction time and grip strength, as well as data on weight loss and gain and the number of falls. This allowed them to look back to see if any signs were present at baseline – that is, when the measurements were first collected from the participants (between five and nine years before diagnosis).

People who later developed Alzheimer’s disease scored lower than healthy people when it came to problem solving, reaction time, remembering lists of numbers, prospective memory (our ability to remember to do something later), and matching. This was also true of people who developed a rarer form of dementia known as frontotemporal dementia.

People who later develop Alzheimer’s are more likely than healthy adults to have fallen in the past 12 months. Those patients who developed a rare neurological disease known as progressive supranuclear palsy (PSP), which affects balance, is more than twice as likely to fall as healthy people.

For each disease studied, including Parkinson’s disease and dementia with Lewy bodies, patients reported worse overall health at baseline.

First author Nol Swaddiwudhipong, a junior doctor at the University of Cambridge, said: “When we looked back at the patients’ histories, it became clear that they had some cognitive impairment years before their symptoms became obvious enough to be diagnosed. impairments were often minor, but in several aspects of cognition.

“This is a step towards enabling us to screen people who are most at risk, such as those over 50 or those with high blood pressure or not exercising enough – and to intervene at an earlier stage to help them reduce their risk.”

Senior author Dr Tim Rittman, from the Department of Clinical Neurology at the University of Cambridge, added: ‘People should not be overly concerned if, for example, they are not good at remembering numbers. Even some healthy people will naturally perform better or worse than their peers. But we encourage anyone who has any problems or notices that their memory or recall is deteriorating to speak to their GP.’

Dr. Rittman said the findings could also help identify people who can participate in clinical trials of possible new treatments. “The problem with clinical trials is that by necessity they often recruit patients with a diagnosis, but we know that by this point they are already some way along and their condition cannot be stopped. If we can find these people early enough, we’ll have a better chance of seeing if the drugs work.”