Grant: Project Grant

We must find better ways to detect Alzheimer disease (AD). New medications can treat the underlying disease but work better earlier on, as do lifestyle interventions like diet and exercise. Spinal taps or technical brain scans (PET scans) are the gold standards used for AD diagnosis. However, not everyone has access to these tests. Blood tests are becoming a popular alternative because they are more accessible. One specific blood test for a protein called p-tau217 has showed great promise in diagnosing the disease accurately and may replace spinal taps and PET scans in many cases. However, there is an issue - even these blood tests aren't ideal for widespread use because they're still somewhat invasive and costly. So, doctors usually only test people already showing signs of memory loss or cognitive decline, like with mild cognitive impairment (MCI), for example. But half of the people with these symptoms don't actually develop Alzheimer's. Growing evidence tells us that observing behavioural changes in older persons can help predict Alzheimer's more accurately since, which is called mild behavioural impairment (MBI). In fact, 30% of persons who develop AD dementia have behavioural changes before being given a cognitive diagnosis like MCI. A checklist called the MBI-C has been developed to identify these changes in behaviour that could indicate the onset of AD. Our goal is to see if using this behavioural checklist in persons with memory symptoms can improve our ability to identify Alzheimer's early on, using the p-tau217 blood test. We will test 202 individuals with memory symptoms, with and without MBI, and use the p-tau217 blood test to determine who has AD at baseline. We will also monitor blood level changes over 3 years in persons with MBI and without. These findings will help us refine our approaches to detecting AD earlier using novel clinical frameworks (MBI) and novel tests (blood).