Dementia Flashcards
What is dementia?
Dementia is a syndrome
Usually of a chromic or progressive nature
And it is deterioration of cognitive function beyond what might be expected from normal ageing
Consciousness is not affected in dementia, this is what helps distinguish it from delirium!
What age is classed as early onset dementia?
The onset of dementia before 65 years
What could you use to screen dementia in the community?
GPCOG (general practitioner assesment of cognition)
Or
6-CIT (six item cognitive impairement test) use if they have attended alone
What can you do in secondary care to diagnose dementia?
If Minimal cognitive impairement is possible then do MoCA (montreal cognitive assesment)
You can use MMSE if minimal cognitive impairement isn’t a possibility but Moca is still preferable
What investigations should be done for dementia?
Routine bloods- FBC, U and Es, Ca2+, glucose, LFTS, TFTS, 12 and folate
If clinically appropiate, the following can be done…
- MSU (UTI)
- CXR (pneumonia)
- serology for syphilis or HIV
- ECG (exclude AF in the contents of vascular dementia)
- neuro-imaging MRI for the subtype of dementia, CT scan for cognitive impairement
What is the management of dementia?
Treat by aetiology as appropriate
Offer advice and support
Make sure they contact DVLA for assesment and stop drving
Refer urgently to neurology if- rapidly progressing or there are neurological signs or symptoms
How do you manage mild cognitive impairement?
Refer to the memory clinic for long term monitoring and early detection
They can continue to drive if safe to do so, don’t need to notify the DVLA.
What are the subtypes of dementia?
Alzheimers (most common-62%) Vascular Mixed Lewy bodies Fronto- temporal
What is alzheimers disease?
A primary neuro degenerative disease which is the commonest cause of dementia
Not really sure what causes it, however genetics are important
Around 15% are thought to be familial
Has a link with autosomal dominant and early onset
What genes are associated with early onset alzheimers disease?
APP
PSEN1
PSEN2
All of these genes are associated with beta amyloid
What is the histopathology behind alzheimers disease?
Neurofibrillary tangles- intracellular accumulations of abnormally folded Tau proteins
Beta amyloid plaques - extracellular abnormal proteins
What is the gene associated with later onset of alzheimers?
APOE
What are the risk factors for alzheimers disease?
Age- usually >65 years old, the risk increases with age!
Family history- increased risk with first degree relatives, even without APOE
Mild cognitive impairement
Risk factors for CVD
Previous traumatic brain injury
Fewer years of formal education
Down syndrome
What is the typical history of someone with alzheimers disease?
Memory loss which is gradual and episodic, they have problems remembering recent events rather than distant memories
May also have cognitive deficits and may have hallucinations however hallucinations are more strongly associated with lewy body dementia
What investigations can be done for dementia?
MRI should be performed to rule out other causes for the presentation
CT is an acceptable alternative
On MRI and CT look for cortical atrophy (shown by enlargement of the sulci), cortical atrophy can be seen in dementia however it can also be seen in an older person generally anyway
On MRI look for focal medial temporal lobe atrophy as this is more specific, can differentiate Alzheimers from dementia with lewy body or vascular dementia
What is the management of alzheimers?
Alzheimers can be treated with cholinesterase inhibitors, these do not slow down the progression however they can improve cognitive function
1st line= donepezil
2nd line= rivastigmine or galantamine
How do cholinesterase inhibitors work?
They work by inhibiting the enzyme acetyl cholinesterase, which normally breaks down acetylcholine and therefore increase the levels of neurotransmitter acetylcholine
What is used to treat severe Alzheimers disease?
Memantine
This is a receptor antagonist which prevents NMDA stimulation by glutamate
In alzheimers there is excess glutamate
Can also be used in mild/ moderate alzheimer patients who can’t tolerate cholinesterase inhibitors usually due to GI symptoms.