Dementia Flashcards
what is dementia
gradual global cognitive decline characterised by memory problems and personality/behavioural changes
normal MMSE score
>27 out of 30
MMSE score indicative of dementia
<24 out of 30
what score in the addenbrooke’s cognitive examination (ACE) is indicative of dementia
<82 out of 100
routine blood tests for patient with symptoms of dementia
FBC U+E LFTs calcium glucose TFTs Vitamin B12 Folate
what radiological investigation is first line for cognitive decline
CT HEAD
- to look for vascular disease and rule out SOLs
most common type of dementia
Alzheimers
pathophysiology of Alzheimers
beta amyloid plaque deposition neurofibrillary tangles of Tau protein
where in brain does Alzheimers first affect
nucleus basalis of Meynert
why is nucleus basal of Meynert important in pathophysiology of alzheimers
it is the main source of acetylcholine for the cortex - beta amyloid plaques prevent synapses from transmitting acetyl choline
presentation of alzheimers
4 As
Amnesia: recall is impaired first. Short term affected before long term- difficulty learning new things.
Aphasia: expressive first, word finding difficulties common.
Agnosia: e.g. difficulty naming an object in hand with eyes closed
Apraxia: impaired motor planning skills e.g. dressing self
genetic condition that increases alzheimers risk
Downs syndrome
Risk factors for alzheimers
family history
traumatic brain injury
Depression
what may be seen on CT alzheimers
temporal lobe atrophy
(affects temporal + partietal lobes the most)
what other imaging modality may be used in Alzheimers
perfusion SPECT
1st line treatment alzheimers
cholinesterase inhibitors
examples of cholinesterase inhibitors
donepezil
galantamine
rivastigmine
what needs to be done before a patient is started on an cholinesterase inhibitor
ECG
- 2nd degree heart block is a contraindication
what is important to monitor whilst a patient is taking an cholinesterase inhibitor
Pulse - side effect of bradycardia
side effects of donepezil, rivastigmine, galantamine
(cholinesterase inhibitors)
bradycardia
GI upset
insomnia
headache, dizziness
2nd line treatment of alzheimers
memantine
mode of action memantine
NMDA antagonist
when is memantine used in alzheimers management
patients who are intolerant/contraindicated to cholinesterase inhibitors
add on drug in mod-severe disease
monotherapy in severe alzheimers
when are symptoms of alzheimers typically worse
in the evening
what scoring system can be used to differentiate between alzheimers and vascular dementia
Hachinski score
hachinski score <4
what type of dementia?
alzheimers
hachinski score >7
what type of dementia
vascular
pathophysiology of vascular dementia
cumulative effects of many small strokes
- vascular changes
vascular dementia risk factors
>60 years old
obesity
hypertension
smoking
vascular disease
diabetes
SPECT scan of vascular dementia
patchy uptake througout
management of vascular dementia
maintain BP in normal range
antiplatelet therapy - aspirin/clopidogrel
statin
what are lewy bodies
eosinophilic alpha synuclein protein cytoplasmic inclusions
how can lewy bodies be detected
immunochemical staining for ubiquitin protein
most common site for lewy bodies to aggregate in lewy body dementia
substantia nigra
presentation of lewy body dementia
fluctuating changes in cognition
visual hallucinations
parkinsonism- gait changes, balance problems ect
sleep disorder seen in lewy body dementia
REM sleep disorder
difference between lewy body dementia and dementia in parkinsons disease
Lewy body: cognitive impairment occurs arround same time as movement disorder
Dementia in parkinsons: movement disorder is present before onset of cognitive decline
drug management of lewy body dementia
same as alzheimers
donepezil/rivastigmine/galantamine
memantine
pathophysiology of frontotemporal dementia
atrophy of frontal and temporal lobes
what is frontotemporal dementia also known as
picks disease
what are pick cells
swollen neurones
what are picks bodies
intracytoplasmic filamentous inclusions
presentation of picks disease
slow progression, changes in personality + social deterioration, loss of inhibitions, impaired memory + language
triad of dementia, urinary incontinence and gait ataxia
normal pressure hydrocephalus
triad of confusion, ataxia, opthalmoplegia
wernicke’s encephalopathy
what is wernicke’s encephalopathy
acute presentation of thiamine deficiency (B1)
what is korsakoff syndrome
chronic manifestation of thiamine deficiency
presentation of korsakoff syndrome
confabulation- false memories believed to be true
anterograde amnesia - cant form new memories
retrograde amnesia - cant remember past
what can cause thiamine deficiency
alcohol misuse - poor nutrition + impaired GI absorption
treatment of wernicke’s/korsakoffs
thiamine replacement
- IM/IV initially
- oral long term
definition of apraxia
cant perform purposeful actions
definition of aphasia
inability to understand speech = receptive aphasia (wernicke’s area)
produce speech = expessive aphasia (Broca’s area)
definition of agnosia
inability to interpret sensations
