People at risk of Alzheimer’s disease have problems with spatial navigation before they have problems with other cognitive functions, including memory, according to a new study led by UCL researchers.
The research, published in Alzheimer’s and Dementia: The Alzheimer’s Association Magazineused virtual reality to test the spatial navigation of 100 asymptomatic middle-aged adults, ages 43 to 66, from the PREVENT-Dementia prospective cohort study.
Participants had a hereditary or physiological risk for Alzheimer’s disease, due to a gene (the APOE-ε4 allele) that puts them at risk for the disease, a family history of Alzheimer’s disease, or risk factors such as of life, such as low levels of physical activity. . Crucially, these participants were about 25 years younger than the estimated age of dementia onset.
Led by Professor Dennis Chan, the study used a test designed by Dr Andrea Castegnaro and Professor Neil Burgess (all from the UCL Institute of Cognitive Neuroscience), in which participants were asked to navigate within an environment virtual while wearing virtual reality headsets.
The researchers found that people at highest risk of developing Alzheimer’s disease, regardless of the risk factor, had selective impairment on the virtual reality navigation task, without corresponding impairment on other cognitive tests. The authors say their findings suggest that spatial navigation deficits may begin to develop years, or even decades, before any other symptoms appear.
First author Dr Coco Newton (UCL Institute of Cognitive Neuroscience), who carried out the work while at the University of Cambridge, said: “Our results indicated that this type of change in navigation behavior could represent the earliest diagnostic sign in the continuum of Alzheimer’s disease: – when people go from being intact to showing manifestations of the disease.
The researchers also found that there was a strong gender difference in the participants’ performance, with deterioration observed in men and not women.
Dr Newton added: “We are now building on these findings to develop a diagnostic clinical decision support tool for the NHS in the coming years, which is a completely new way of approaching diagnosis and will hopefully help people to obtain a more timely and accurate diagnosis.
“This is particularly important with the emergence of anti-amyloid treatments for Alzheimer’s, which are considered most effective in the early stages of the disease.
“It also highlights the need for more studies on the different vulnerability of men and women to Alzheimer’s disease and the importance of taking gender into account for both diagnosis and future treatment.”
Professor Chan said: “We are excited about these findings for two main reasons. Firstly, they improve the detection of the clinical onset of Alzheimer’s disease, critical for the rapid implementation of treatments.
“Second, the virtual reality navigation test builds on our knowledge of the spatial properties of cells in the temporal lobe of the brain, and the application of cellular neuroscience to clinical populations helps close the gap in understanding “How disease at the neuronal level can result in clinical disease manifestation. This knowledge gap currently represents one of the biggest barriers to progress in Alzheimer’s research.”
The research was carried out in collaboration with the University of Cambridge, jointly funded by the Alzheimer’s Society and a research grant from MSD.
Dr Richard Oakley, Associate Director of Research and Innovation at Alzheimer’s Society, said: “One in three people born today will develop dementia, and early and accurate diagnosis of the diseases that cause the condition is vital for people to people access appropriate medical care. support, plan for the future and receive appropriate treatment.
“The very early symptoms of dementia can be subtle and difficult to detect, but problems with navigation are thought to be some of the first changes in Alzheimer’s disease.
“This study was partly funded by the Alzheimer’s Society and used virtual reality technology to show that a healthy person’s navigation abilities are related to their risk of dementia, based on genetic and environmental factors.
“This innovative technology is a long way from becoming a diagnostic test, but it provides more evidence for the role of navigation skills as an early sign of Alzheimer’s disease. More work is needed to develop this technology, but it will be exciting to see it.” “how this research may offer a way to detect disease-specific changes early and help people living with dementia in the future.”