Until now is has been believed that Alzheimer’s disease and other forms of dementia could be diagnosed only when symptoms appear which almost always means when patients are in their 70s or 80s. Now the latest research shows that some brain lesions are characteristic of Alzheimer’s disease and can be detected in the brains of healthy people in their 40s. Along with this a simple mental skills test may be able to detect the problem many years sooner than previously thought.
They study was conducted by Australian and British researchers and involved a group of 431 healthy Canberrans aged from 44 to 48. The researchers found that those who performed less well on a specific cognitive tests were much more likely to have the lesions in the brain’s white matter. The lesions could be detected using magnetic resonance imaging scans or MRI scans and showed up as tiny dots. These patients did not have any symptoms.
According to lead author David Bunce, a research fellow at the Centre for Mental Health Research at the Australian National University, it is still unclear if any of those with the lesions would go on to develop dementia. But these lesions are similar to those found in patients who died with Alzheimer’s disease. He said, “It’s one of the first studies to demonstrate that these white-matter lesions exist in such a young group… Secondly, we have been able to predict these lesions through fairly simple-to-administer cognitive tasks.” Professor Bunce is also from the Centre for Cognition and Neuroimaging at London’s Brunel University.
The cognitive test involved asking participants to react as quickly as possible to the illumination of one of two lights, by pressing a corresponding button. The lesions were found in those whose performance was highly variable i.e. reacting within 200 milliseconds at one attempt, and taking 450 milliseconds the next. Those who reacted with similar rates with wither fast or slow tendencies did not have the lesions.
Professor Bunce explained, “In the same way that middle-aged people go to the GP and have a blood pressure test, potentially it might be possible to use some people's reaction times, measured on a laptop or a PC (to gauge their risk of later dementia)…However, at the moment we don’t know how to head off dementia and Alzheimer's later on.” He still advised a healthy lifestyle by eating well, exercising well and avoiding tobacco and excessive alcohol to avoid the disease.
The research is published in the journal PLoS ONE (Public Library of Science-ONE).