Dementia Flashcards
What is dementia?
A set of symptoms including declining cognitive function. memory loss, difficulty thinking, personality change.
Dementia is an umbrella term referring to disorders like Alzheimer’s and others
What does the frontal lobe do?
Voluntary + planned motor behaviours
Motor speech area, Broca’s
Personality
Planning
What does the temporal lobe do?
Hearing
Language comprehension
Semantic knowledge
Memory
Emotional / affective behaviour
List some types of dementias?
Alzheimer’s
Fronto-temporal dementia
Dementia with Lewy bodies
Vascular dementia
Many more
What would frontal-temporal dementia present like?
Personality and behaviour change
Followed by breakdown in attention and cognitive function
What would dementia with Lewy bodies present like?
Visual recurrent hallucinations
Fluctuating cognition
Pronounced variation in alertness
Depression + sleep disorders
Parkinsonism
What is dementia with Lewy bodies?
Dementia caused by tiny deposits of protein in nerve cells
The deposits are called Lewy bodies
Their presence results in a loss of connections between nerve cells and nerve cell death
What is vascular dementia?
Dementia caused by a reduced blood supply to the brain
This often occurs as a result of multiple mini strokes
What would vascular dementia present like?
Stepwise deterioration with declines, followed by short periods of stability
What is fronto-temporal dementia?
Signs of degeneration of fronto-temporal lobes, but no Alzheimer’s histology
What is the pathogenesis of Alzheimer’s?
Deposition of amyloid plaques and neurofibrillary tangles.
Plaques are made of protein fragment beta-amyloid
Tangles consist of an abnormal version of tau, a protein normally involved in maintaining the internal structure of the nerve cell.
These things all lead to atrophy of the brain and thus declining cognitive function
What does a brain affected by Alzheimer’s look like on a CT scan?
Atrophied
Shrunken
What are the risk factors for Alzheimer’s disease?
Family history
Down’s syndrome
Vascular risk factors: diabetes,
high BP
Depression / loneliness
Smoking + alcohol
What is semantic dementia?
Loss of semantic memory
General knowledge, facts, names of objects, words
They may not know what a sheep or a chair is for example
Investigation of dementia?
Full history from patient and someone who knows them well
Assess cognitive function using tests like mini mental state exam
Blood tests to exclude other causes:
- vitamin deficiencies
- liver function
- thyroid
Brain CT: only if young or unsure of cause
Assess what level of support the patient needs: full time care?
Management of dementia?
Acetylcholinesterase inhibitors
Memantine (anti-glutamate)
Control of vascular factors: BP, diabetes
Treat mood and anxiety
Encourage them to be socially and cognitively active
Provide support for family, and for patient
Which types of memory are affected in Alzheimer’s and which are not?
Short term memory readily affected, resulting in confusion
Long term, autobiographical memory is usually less affected
How would you differentiate between vascular dementia and Alzheimer’s disease?
Similar symptoms
Vascular may have high BP, a history of strokes, more stepwise progression of symptoms
Alzheimer’s involves deposition of plaques in the brain, what are they made of?
Amyloid
Alzheimer’s involves the deposition of neurofibrillary tangles in the brain, what are they made of?
An abnormal version of the protein Tau
What is Tau and what does it do?
A protein usually involved in maintaining the structure of nerve cells
What is the effect of amyloid plaques and neurofibrillary tangles on the brain?
Affects conduction of impulses in the brain, slows them down
Causes atrophy
Where are the amyloid plaques deposited?
Outside the neuron cells
Where are the neurofibrillary tangles deposited?
Inside the neuron cells
