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Health and medicine
Course: Health and medicine > Unit 9
Lesson 10: Dementia, delirium, and Alzheimer's- Dementia and Delirium, including Alzheimer’s
- What are dementia and Alzheimer's
- Alzheimer's disease: Plaques and tangles
- Other types of dementia
- Risk factors for dementia
- Stages of dementia and Alzheimer's disease
- Diagnosis of dementia and Alzheimer's disease
- Treatment of dementia and Alzheimer's disease
- What is delirium?
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Stages of dementia and Alzheimer's disease
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Want to join the conversation?
- Atwhat does he mean when he says that one of the complications is "falls"? 5:02
I don't think he means falling down.(4 votes)- I'm pretty sure that he does mean falling down. Notice that he also says that movement can be impaired, so this would make sense.(6 votes)
- can any one of these stages happen before another like stage 6 happen before stage 1?(4 votes)
- No, because dementia/Alzheimer's is brain decay. What stage the patient is in depends on how much decay there is in their brain.(5 votes)
- Is hallucinations, or seeing things that aren't there, part of Alzheimer's? If so, what stage would that fit into? Thanks for any help that can be provided.(2 votes)
- Hallucinations can be a symptom of Alzheimer's (specifically of Dementia) but you should also be aware that one of the main symptoms of Delirium is hallucinations and delusions (they commonly happen at night as well).
Check the first chapters of this course here on Khan.(1 vote)
Video transcript
- [Voiceover] So, Alzheimer's
disease, vascular dementia, Lewy body dementia, and
every other type of dementia causes damage to your brain cells, right, which, in turn, causes some
difficulties with various things your brain controls,
like memory, language, reasoning, and judgement. But a lot of the time,
these signs and symptoms can present themselves
slightly differently. Since Alzheimer's disease
accounts for the majority of dementia cases and
the other forms can often overlap anyways, the
main focus here will be on the symptoms and progression
of Alzheimer's disease. Dementia in Alzheimer's
disease typically develop over the course of years,
but the speed at which it develops can vary pretty dramatically, from four years in some patients, eight in others, and
even as high as 20 years in some cases. We're going to go through
some of the general stages of progressing Alzheimer's disease, but considering that it's
such a gradual disease, it's actually really tough
to classify this progression. And it's important to remember
that there are no clear-cut or well-defined stages,
and many of these stages that we'll go through can even overlap. But, with that said, there
are a few models that are used for the progression of
Alzheimer's disease, and we're going to sort
of combine the definitions from a more broad three-stage model and also the more specific
seven-stage Reisberg Scale. So, from the three-stage
model, we have the very early to mild stages of
Alzheimer's, lasting about two to seven years. And then, if we look
at the Reisberg Scale, stage one is simply no impairment. So, your memory and cognitive
abilities appear normal, especially to everyone else. If there are any
impairments, they might only be slightly apparent to
the patient themselves. Stage two, however, is a
very mild cognitive decline. So, maybe they have
some trouble remembering recent events or information,
but it could be more subtle things like forgetting a
word or misplacing things. And, again, at this stage,
these lapses and changes in thinking aren't usually
detected by friends, family, or even medical
personnel, especially considering half of all people over
65 begin noticing problems with concentration and word recall just as a normal consequence of aging. Stage three is signs of
early confusion and mild cognitive impairment. At this point, subtle
difficulties can start to impact their daily life. The patient might consciously
or even subconsciously try to hide these issues. They might have trouble retrieving words, remembering what was just said or read, and planning and organizing,
which can all start to affect life at home or at work. It could still be difficult,
though, to diagnose Alzheimer's at this very early stage. Now, stage four is considered
mild Alzheimer's disease. This stage lasts about two years. And during these two years,
things like financials and math start to become very challenging. And the ability to remember recent events and what was just learned
becomes increasingly difficult. The patient might have
trouble carrying out tasks, especially if there
are specific sequences, like cooking or driving. But the patients are still
usually able to recognize their family and friends,
although a diagnosis at this stage is usually accurate. Stage five is considered early dementia to moderate Alzheimer's disease. In this stage, cognitive
decline starts to become more drastic, and the
patient requires assistance. They'll probably have
trouble remembering things like address or phone number
and can be disoriented very easily regarding the time or place. Decision and judgement
skills can also be affected, like choosing the appropriate clothes for the day or season. And so, the patient may
need increased supervision. This stage can last an
average of about 1.5 years. Stage six is considered moderately severe Alzheimer's disease, and in this stage, there's a significant lack of
awareness of present events, and this inability to
remember the past and carry on a conversation, and they'll
likely need help with basic daily tasks like getting dressed, eating, and going to the bathroom. The patient will likely
be unable to recall names of family members but will likely know that they're familiar. This stage lasts about 2.5 years. In the final stage or
stage seven, speech becomes severely limited, and
we see a serious decline in basic abilities. Even movement abilities
begin to be affected as the disease has started
to spread to those areas of the brain, so eating, walking, sitting, or even standing up all start to fade. And patients will likely
need extensive assistance eating and drinking, as
they can lose the ability to discern when they're thirsty or hungry. And so they need total
assistance around the clock for all functions of daily life and care. And at this stage, due
to these inabilities, they become much more susceptible to secondary complications,
diseases and infections, especially pneumonia and falls. And this final stage can last from one to two and a half years. But, again, it's very important
to stress the flexibility in this timeline, in these stages. Not all patients with
Alzheimer's will experience this exact progression,
and some may deviate significantly from the expected
duration with each stage and the disease itself.