In the previous video, we talked about what dementia is, and how it is different from normal aging. We also discussed how there could be a progression from mild cognitive impairment to full-blown dementia.
Symptoms & diagnosis
Now, suppose you or a loved one has some of the classic dementia symptoms, like cognitive changes such as memory loss, problems communicating, or getting lost. Or psychological changes like inappropriateness, paranoia, or agitation. You go to see the doctor, what can you expect?
The doctor will start with a clinical exam and a medical history. If you’ve had symptoms for more than several months, the next step will be neurocognitive testing.
Neurocognitive tests are simple tests you take with paper and pencil, or on a computer screen. These measure the cognitive functions most likely to be affected by dementia, such as memory and recall, processing speed, attention, and language skills.
By comparing your test scores to the healthy population of people your age – or to your scores from a previous time – it’s possible to determine whether you have a cognitive impairment.
Typically, a collection of tests is given, and together they clarify which cognitive domains are impaired.
Memory recall test
One example of a neurocognitive test is a memory recall test. To test working memory, a doctor might ask to you remember a list of five words and repeat them back immediately. Then, to test short-term memory recall, the doctor might ask you for that same list of words five minutes later, while keeping you busy with other things in between. Difficulty with either immediate or delayed recall could signal a problem.
Another neurocognitive test is clock drawing. The doctor will ask you to draw a clock face with hands showing, for example, 10 minutes after 11. Normally you’d draw it this way:
But with dementia, the “10” becomes confused with the number 10 on the clock face.
Neurocognitive testing is the most reliable way to test for dementia. The paper and pencil versions require a professional to administer them, usually a neuropsychologist or neurologist.
In recent years, there has been a move toward computerized testing, which can collect more accurate and sensitive measures, for example measuring response time at the millisecond level.
By making neurocognitive tests automated and more accessible, people can take them at home and take them more often – and this allows people to take an active role in monitoring their brain health – identifying any changes as soon as they happen and keeping tabs on any significant changes.
Similar symptoms of dementia
A diagnosis of dementia is serious, and therefore it’s only made if all other causes can be ruled out. This is because other conditions can look like dementia, like kidney or liver diseases, vitamin or iron deficiencies, diabetes, circulatory problems, or chemotherapy.
If lab tests and blood work come back negative, some doctors will also take a brain scan, such as an MRI or a CT scan, just to be sure that the symptoms you’re experiencing aren’t due to other factors like a tumor.
Research: biomarkers & automation
Diagnosing dementia is tough and an active area of research, and there are a lot of researchers working to change that, specifically for dementia caused by Alzheimer’s disease.
One of the most exciting new fronts is studying biomarkers – genes, proteins, or any molecule in the body that is associated with a disease state.
Although none of these have been validated yet, scientists are working on using both genetic risk factors and physiological biomarkers to give patients more information about their risk of developing Alzheimer’s. We’ll tell you more about prevention and risk factors in the next videos.