Dementia Flashcards
What is Dementia?
Dementia is a neurodegenerative syndrome with progressive decline in several cognitive domains
What are the different types of Dementia, in order of prevalance?
- Alzheimers Dementia
- Vascular Dementia
- Lewy Body Dementia
- Fronto-temporal Dementia
What are the clinical features of Alzheimers Disease?
=> As time progresses:
- Asymptomatic
- Short term memory loss
- Loss of motor skills + language
- Long term memory loss
- Disorientated
- Bedridden
- Death
=> Plaques and tangles build up as diseases progresses
=> The 4As:
- Aphasia
- Agnosia
- Apraxia
- Amnesia
What are the risk factors of Alzheimers Disease?
- 1st degree relative with Alzheimers
- Downs syndrome
- Homozygous for ApoEe4 gene
- Loneliness
- Smoking
What is the pathophysiology of Alzheimers Disease?
- Amyloid precursor protein is an integral protein within the cell membrane of neurones
- In AD, this protein is broken down incorrectly, with the broken pieces clumping together to form B amyloid plaques
- B amyloid plaques disrupt signalling between neurones
=> B amyloid plaques outside the neurone initiate pathways inside the neurone :
- activation of kinase which phosphorylates TaU protein
- Eventually, TaU proteins tangle together to form neurofibirally tangles
=> B amyloid plaques + neurofibrillary tangles cause atrophy of the brain
What are the 3 main brain atrophy changes?
- Narrowing of gyri
- Widening of sulci
- Ventricles enlarge
What are the investigations in suspected Alzheimers Disease?
=> Bloods
- In primary care to help exclude reversible causes
=> Brain CT/MRI
=> 10-CS, 6-CIT (recommended by NICE)
=> Mini Mental State Exam (not recommended by NICE) 25 < normal 20-24 suggests mild dementia 13-20 suggests moderate dementia 12 > suggests severe dementia
=> Abbreviated Mental Test Score (not recommended by NICE)
What is the management of Alzheimers Disease?
=> Ach-estrase inhibitors first line
- Donepezill, Rivastigimine, Galatamine
=> NMDA antagonists second line
- Memantine
=> Antipsychotics:
- Should only be used if the person is at risk of harming themselves
=> Vitamin supplementation
What are the contraindications and adverse effects of Donepezil?
=> Contraindications:
- Bradycardia
=> Adverse effect:
- Insomnia
What is Vascular Dementia?
=> Cumalative effect of:
- Stroke
- TIAs
- Stepwise detoriation characteristic
- Evidence of arteriopathy
What are the clinical features of Lewy Body Dementia?
- Progressive cognitive impairment
- Early impairments in attention and executive function
- Visual hallucinations
- Eventual development of Parkinsonism
What is the pathophysiology of Lewy Body Dementia?
- Mainly affects cortex and substantia nigra
- Cholinergic and Dopaminergic neurones contain protein known as a-synuclein
- This protein is mis-folded in Lewy Body Dementia, therefore aggregates
- Neurones in which this protein is mis-folded and aggregates die
What are the investigations in suspected Lewy Body Dementia?
=> Single photon emission computed tomography
What is the management of Lewy Body Dementia?
- Acetylcholinesterase inhibitors
- NMDA antagonists (Memantine)
=> Neuroleptics (antipsychotics) should be avoided as they further decrease the already low dopamine levels
What are the clinical features of fronto-temporal dementia?
- Onset < 65
- Insidious onset (don’t really realise its happening)
- Behavioural/personality changes
- Hyperorality
- Disinhibition
- Emotional unconcern
=> Episodic memory and spatial orientation are preserved until later changes
