How Do We Test for Dementia?

"Unfortunately, there is not one single test that confirms dementia while you are alive," says Dr. Julie Brody Magid, clinical director of the Harvard-affiliated McLean Hospital Memory Disorders Assessment Clinic. "The testing process is multilayered and takes many things into consideration. Going through this evaluation may help identify memory problems, before they get worse."

An article in the upcoming May issue of Harvard Men’s Health Watch entitled “Testing for dementia” explains that the symptoms of dementia include memory loss, problem-solving difficulties and language issues. The author says that behavior and emotions also can be impacted. The symptoms are often subtle in the early stages and then get progressively worse. These symptoms can continue to interfere with daily life tasks, such as remembering to attend appointments, taking your medications, or paying bills. Dementia patients also may have trouble preparing meals or driving safely.

The most common kind of dementia is Alzheimer's. Its symptoms include having a hard time retaining recently acquired information and remembering recent conversations. Those with Alzheimer's disease  may also have difficulty monitoring upcoming events and may make repetitive comments.

A physician can begin a dementia screening with a brief test, like the Mini-Mental Status Exam or the Montreal Cognitive Assessment. These take about 10 minutes and include tasks, such as learning a list of words and then recalling them minutes later and identifying the similarities between words. Your doctor will determine if your screening test score and symptoms warrant more testing. If so, she will refer you to a memory clinic for a full assessment, which includes a neuropsychological evaluation and biomarker tests.

The neuropsychological evaluation lasts about four hours. It includes a series of in-depth analyses, such as one-on-one interviews and written and oral tests, designed to gauge specific cognitive functions, like attention, problem solving, spatial skills and executive functioning. These test scores are compared with what an average person of the same age and education level may experience.

Biomarker tests may include an MRI to look for structural changes in the brain, like small lesions or changes in the white matter. This may show damage to brain tissue, due to small strokes and suggest that memory issues may be related to vascular disease or “vascular dementia.” This scan also can show shrinkage of the cortex (the area that processes memory, attention and problem solving) or less volume in the hippocampus (the region involved in short- and long-term memory). While there’s some amount of brain shrinkage with normal aging, significant changes in brain volume may mean a higher probability of early Alzheimer's.

Once your doctor reviews everything, and if a cognitive disorder is confirmed, it is categorized as mild, moderate, or severe, which will help the doctor prescribe the best available treatments.

If Alzheimer's is suspected, there are prescription drugs that can help retard symptom progression. If the diagnosis is vascular dementia, it's important to manage cardiovascular risk factors such as taking medications to control blood pressure and cholesterol levels, exercising regularly and following a heart-healthy diet.

With memory loss, you must be as proactive as with any other health issue. The more you delay in taking action, the fewer tools that are available.

Reference: Harvard Men’s Health Watch (May 2020) “Testing for dementia”