The Ageing Brain Flashcards
Structural changes include the following 4 things:
Cerebral atrophy, Amyloid plaques
Neurofibrillary tangles, Cerebral white matter lesions (cerebral small vessel disease)
As we age, the brain atrophies– loss of ?
Atrophy is not ?:
? most affected
? are also affected significantly. ? relatively protected
As we age, the brain atrophies– loss of neurones, and loss of connections between them
Atrophy is not global:
Prefrontal cortex and striatum are the most affected
Temp lobe, hippocampus and cerebellum are also affected significantly. Occipital lobe relatively protected
Describe the changes in grey matter and white matter mass during cerebral atrophy.
Grey matter mass ?
White matter mass ?, then ?
Overall more ?
Grey matter (neuronal cell bodies) is involved in ?
White matter is made up of ?, hence is responsible for ?
Grey matter mass decreases steadily throughout adulthood
White matter mass increases til 40, then begins decline
Overall more white matter loss than grey matter loss
Grey matter (neuronal cell bodies) is involved in muscle control, sensory perception, memory, emotions, speech and decision making
White matter is made up of neuronal axons, hence is responsible for communication w/in the nervous system
Describe cerebral white matter lesions:
Cerebral white matter lesions = ?
- Occur due to ?, leading to?
- These changes inc ?
- They’re associated with ? and are possibly related to ? related to loss of ?
?=most common causes
White matter lesions can be recognised in ?
Cerebral white matter lesions = leukoaraiosis
- Occur due to changes in the small perforating vessels of the brain–> chronic white matter ischaemia
- These changes inc plaque accumulation, inflammation and chronic damage
- They’re associated with vascular risk factors and are possibly related to small vessel strokes or hypoperfusion related to loss of autoregulation
Age and hypertension related SVD=most common causes
White matter lesions can be recognised in CT
Is the brain sensitive to oxidative stress?
The brain is ?
Accumulation of ? is responsible for the ?
It is associated with ?
The brain is unusually sensitive to oxidative stress
Accumulation of oxidative damage to DNA, lipids and protein by free radicals is responsible for the functional decrease in the aged brain
It is associated with inflammatory and microvascular changes
What happens to cerebral blood flow as you age?
This is as a result of which 3 things?
In the aged brain, cerebral blood flow is reduced by -20%
This is a result of narrowed arteries, fluctuant BP and changes in homeostasis (e.g. reduced efficacy of the myogenic response)
There is a chemical change in neurotransmitters and the BBB in the brain as we age. Expand on this further.
Reduced ? – leads to ?
Reduced ? – ?
Reduced ? – ?
Age reduces ? of binding sites and receptors of ?
Elderly BBB becomes ?
Also ? across the BBB makes the elderly brain ?
Reduced ACh – leads to cognitive impairment
Reduced dopamine – Parkinsonism, eg as reduced arm swing when walking, increased rigidity
Reduced 5-HT – depression, circadian rhythm changes
Age reduces production and availability of binding sites and receptors of many key NTs
Elderly BBB becomes more permeable to nutrients, metabolites and toxins
Also reduced transport of glucose, proteins and hormones across the BBB makes the elderly brain more susceptible to hypoglycaemia
For the age related change, summarise the consequence:
Changes within the ageing brain mean that some functions are altered, whilst others are preserved -What are these?
Explain the indicators of delirium
Indicators of delirium inc fluctuations or changes in:
4 things
These changes= ? These indicators can present as:
- The patient being just ?
- Poor ? –pt can’t ?
- Pt ?
- The patient is ? OR ?
- ?
- Pt has a reduced ?
- Loss of ?
Risk factors for delirium: 4 things
Indicators of delirium inc fluctuations or changes in:
- Cognitive function
- Perception
- Physical function
- Social behaviour
These changes= worse in the evening (sun-downing). These indicators can present as:
- The patient being just “more confused”
- Poor attention –pt can’t give a history
- Pt looks round the room (can’t work out where they are)
- The patient is agitated OR v quiet/drowsy
- Hallucinations
- Pt has a reduced ability to care for themselves
- Loss of mobility
Risk factors for delirium:
> 65 years of age
Fractured neck of femur
Severe illness
Dementia
What are the types of delirium?
Which one is misatken for 2 other things?
Hyperactive: pt is predominantly restless and agitated
They show increased motor activity, a loss of control over their activity, restlessness and wandering
Hypoactive delirium: drowsy and inactive. Most common type
Decreased activity + action speed, slower speech, less speech, reduced awareness of their surroundings, listlessness and withdrawal
Hypoactive delirium often mistaken for depression or dementia
Mixed: pt hyperactive in some aspects and hypoactive w others
How do you assess for delirium?
Since it’s unlikely we know what the patient is usually like, we need a collateral history
We can use cognitive screening tests:
4AT ( 4 A’s test)
Abbreviated Mental Test Score (see below)
Montreal Cognitive Assessment
Basic investigations to try and find the underlying cause (e.g. FBC to look for infections, urine samples to rule out UTIs, etc…)
What is the 4AT test?
4 or more: Possible delirium +/- cognitive impairment
1-3:Possible cognitive impairment
0: Delirium or cognitive impairment unlikely
What is the AMTS?
Abbreviated Mental Test: AMTS is another rapid screening tool that we can use
It involves a series of 10 questions, with a score out of 10 being produced at the end
Can you tell me your age?
What’s the time (to the nearest hour)?
I’m going to give you an address, which I’ll ask you to repeat back to me now and again later on when I ask?
Can you tell me what year it is?
Can you tell me the name of this place?
Can you identify 2 people (who am I, who is that)?
Can you tell me your date of birth?
Can you tell me which year WWI ended in?
Can you name the present monarch?
Can you count back from 20 to 1 then tell me the address we mentioned earlier?
What is the pathophysiology of delirium? How do you investigate for delirium?
the cause of delerium is oftern ?
Delirium is thought to be due to an acute increase in ACh and DA levels in the brain
This is maybe mediated by an acute stress response, causing increased cortisol, symp activation + cytokines
The cause of delirium is often multifactorial
Investigations:
- Delirium screen
- Routine bloods
- Calcium/B12/folate/TSH
- Glucose
- MSU ( Midstream specimen of urine )
- CT head
What are the causes of delirium?
Include metabolic, medications, neurological, environmental factors.
Draw a table to differentiate between delirium dementia and depression.
onset, course, consciousness, psychomotor, attention, reversibility
a
