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Diagnosis of dementia and Alzheimer's disease

Visit us (http://www.khanacademy.org/science/healthcare-and-medicine) for health and medicine content or (http://www.khanacademy.org/test-prep/mcat) for MCAT related content. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video. Created by Tanner Marshall.

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  • female robot grace style avatar for user Inger Hohler
    How useful is the mini-cog test really in different types of dementia? I've seen a number of demented people in care that were still able to remember the words after drawing the clock, and drawing the clock correctly, but were quite incapable of taking care of themselves. Being able to draw ten past 11 correctly does not always mean that the patient comprehends that if the clock says 2 and it's pitch dark and raining, it is a bad idea to wait without a raincoat for the afternoon bus which will arrive in 12 hours. Similarly, being able to remember 3 words after a short break does not mean the patient will remember to eat, or not to buy that 8th bottle of washing up liquid in just as many days.

    In fact I've been told by a relative that in her area elderly people are actively practicing for the mini-cog, fearing the loss of their driver's license. They know the local doctor always uses the same three word and the same time for the clock. Presumably, having practiced will make it easier to pass than being unprepared, even for someone with early stages of dementia. In the Diagnosis video, the diagnosis of Frontotemporal dementia seem to require a different approach, but vascular dementia which is not that uncommon (up to 50% of dementia cases in some populations) can also present with damages in areas that circumvent the topics tested with the mini-cog. Also, if an early diagnosis of Alzheimer is desirable, I would have thought that the mini-cog is not a good tool for the early signs.
    (8 votes)
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  • blobby green style avatar for user D Jeanne Alvarez
    What are the chances of someone with learning disability and advanced age being told that they have loss of memory due to dementia, ignoring the similar problems that they have struggled with all their lives?
    (3 votes)
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    • starky sapling style avatar for user Rebecca Lundahl
      It is true though that one who suffers from learning disabilities, has low education or there is a language barrier the results can be falsely low in the MMSE.
      But, as he says in the video, when diagnosing dementia one has to discern whether or not the symptoms (Be it learning difficulties or memory loss) is the result of a underlying disease which has symptoms that mimic those of dementia.
      (2 votes)
  • orange juice squid orange style avatar for user hi
    Why are brain scans not used more often and directly? Are they not more reliable than the other evaluations? Is it a cost issue?
    (2 votes)
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Video transcript

- [Voiceover] So there isn't one stand-alone test that will show whether someone has dementia or Alzheimer's disease, since the typical symptoms like memory loss, confusion, and others, can have a whole slew of potential causes. That being said, it's not usually diagnosed until a complete medical assessment is performed. But what all does that entail? Well, first off, a healthcare professional might take a look at the patient's history. They'll try to gather information from the patients themselves as well as from their friends and family. They'll probably ask questions like what kind of symptoms have you noticed? Or when did you start noticing them? How often do they happen? And have you noticed them getting any worse? They'll also try to evaluate the patient's emotional state. A lot of the time the patient might be completely unaware of their current state or they might be in denial about it. And this can be tough because sometimes even other family members will deny its progression because many of the early signs of dementia also tend to look just like normal signs of aging. And this is just another reason why it makes diagnosis of dementia very, very hard and why we have to rely on other methods of diagnosis as well. So a physical examination can also be done. In these, your doctor will check things like your hearing or your eyesight, your heart and your lungs, your temperature, your blood pressure, and your pulse. And they may also take things like blood and urine samples. Information from these can help the doctor figure out if there are any other underlying health issues that are causing or contributing to the dementia itself, like heart problems and vascular dementia or if there's another condition that's mimicking symptoms of dementia, since other conditions like anemia or depression, infection, diabetes, kidney disease, and others can also cause dementia-like symptoms, like confused thinking and memory problems. But besides physical exams, a neurological evaluation may also be done. And this'll look at the patient's nervous system and will test things like balance and sensory function using lights and also your reflexes, using that tiny hammer and lightly tapping it on the knee. The doctor might also give the patient a cognitive or a neuropsychological test, which are used to kind of objectively measure the patient's current memory, language skills, math skills, and other abilities as they relate to mental function. And one big one's called the mini mental state examination or MMSE. And this test can be particularly helpful in diagnosing dementia because it looks at orientation, memory, and attention. For example, it might ask to follow verbal or written commands or write down a sentence spontaneously or copy a complex shape. And depending on the score, a certain level of dementia might be suggested. Scores of about 20 to 24 suggest mild dementia, 13 to 20 suggests moderate dementia, and less than 13 would suggest a severe case of dementia. And typically patients with Alzheimer's disease tend to drop two to four points on average every year. Another more simple test that might be administered is called the mini-cog test. In this test the patient is asked to name three objects and then repeat them back to the doctor, like car, chair, and mug. For the next part, the patient is asked to draw an analog clock and also asked to draw a specific time. Thirdly, the patient's asked what those three objects initially were, car, chair, and mug. If the patient fails one or all of these tests, it might suggest signs of dementia and may require a further evaluation. Another potential test is the psychiatric evaluation or mood assessment. They'll try to assess the patient's current level of well-being, looking for signs of depression or other mood disorders that can also contribute to symptoms that overlap with dementia symptoms. Finally, the patient might have brain scans. With a brain scan the brain's actually visualized through techniques like computed tomography or CT scans or magnetic resonance imaging or MRI. And there are several reasons why we might want one these performed. They might be useful in identifying larger masses, like tumors, that can be contributing to the cognitive impairment. But it might also help in making a differential diagnosis, meaning that we'll try to look to figure out what type of dementia is at play. Sometimes by looking at where the most atrophy of brain tissue is localized, we can figure out what type of dementia it is. For example, atrophy that's localized to the hippocampus might suggest Alzheimer's disease or the frontal lobe might suggest frontotemporal dementia or vascular pathologies that are visualized might suggest vascular dementia. And another reason for a brain scan might be to monitor disease progression. Several imaging sessions over several years might show how the brain has changed over time. More atrophy might be indicative of disease progression whereas if the atrophy has stayed the same over time, it might suggest that a different or a more static cognitive disease is at play. Finally, imaging is really, really valuable for research purposes, especially with respect to structural imaging and figuring out which structures are affected first by the disease in addition to any chemical processes that might be involved. And this information helps physicians and researchers alike understand dementia as a disease and develop more effective treatments in the future.