(neuro) dementia Flashcards
what is the commonest cause of dementia?
commonest cause of dementia is Alzheimer’s disease (AD)
what is dementia?
fatal, neurodegenerative disorder characterised by progressive cognitive, social and functional impairment
what are the main causes of dementia in
a) the younger population?
b) the elderly?
a) early-onset dementia = rare causes
b) late-onset dementia = Alzheimer’s disease, vascular dementia
what are the most common forms of dementia?
Alzheimer’s disease
vascular dementia
frontotemporal dementia
dementia with Lewy bodies
what are the potentially reversible causes of dementia?
depression
alcohol-related brain damage
endocrine causes
B1/B12/B5 deficiency (especially B12 = increased cognitive deficits)
(must know these and try to treat them! to prevent progression)
which medication has had the most significant, albeit very small, impact on dementia treatment?
acetylcholinesterase inhibitors
why is it hard to diagnose dementia in clinic?
- disease follows a hetergenous spattern
- elderly present with multiple co-morbidities
- younger patients present more typically
(clinical history is essential!)
what are the pathological features of Alzheimer’s disease?
vessel wall pathology
parenchymal ischaemic changes
neuronal tau
amyloid beta plaques
TDP-43
alpha-synuclein
what should you ask patients in a memory clinic consultation?
skills:
- memory
- language
- numerical, executive, visuospatial skills
- neglect phenomena
- route finding & landmark identification
psychiatric:
- delusions, hallucinations, agitation
behavioural:
- personality and social conduct
- sexual behavior
- eating, mood, ADLs
which type of history is key in a dementia history?
collateral history!
= patient may have reduced insight which can be partially made up for by taking a collateral history
what type of dementia are subtle progressive changes associated with?
Alzheimer’s
what type of dementia are large progressive changes associated with?
vascular dementia
define dementia
severe loss of memory and other cognitive abilities which leads to impaired daily function (regardless of the underlying cause)
what does the clinical examination for dementia consist of?
neurological exam (cranial nerves, upper/lower limbs, gait)
focused tests
- frontal lobe function
- MMSE
what investigations are carried out for dementia?
MMSE, ACE III
bloods
amyloid PET, sMRI scan
how does MMSE compare to ACE III?
ACE III takes slightly longer & is more memory focussed
which blood tests are carried out for a patient with suspected dementia?
FBC, inflammatory markers
TFTs, renal profile
glucose, B12 and folate
clotting factors
syphilis serology, HIV
caeruloplasmin
how does Alzheimer’s present on an sMRI?
- narrowed gyri, widened sulci
- ventricles dilated and enlargened
- medial temporal volume loss
- hippocampal volume loss (fill w CSF subsequently)
= amnestic presentation of disease
what are the possible differentials for dementia?
Alzheimer’s
FTD
vascular dementia
dementia w Lewy bodies
functional neurological disorder
depression
delirium
(more acute = UTI)
how is dementia managed?
1) acetylcholinesterase inhibitors
2) watch & wait (need to see progressive deterioration before clinically diagnosing)
3) treat behavioral changes (anti-psychotics, anti-depressants)
4) occupational, therapy, social services
how does Alzheimer’s disease dementia often present?
subtle, insidious amnestic/non amnestic presentations
how does vascular dementia often present?
related to cerebrovascular diseases with a classical step-wise deterioration +/- multiple infarcts
how does dementia with Lewy bodies often present?
cognitive impairment before/within 1 year of Parkinsonian symptoms, visual hallucinations and fluctuating cognition
how does frontotemporal dementia often present?
behaviour variant FTD, semantic dementia, progressive non-fluent aphasia
what are some classic clinical signs of Alzheimer’s in a consultation?
lack insight into their condition and extent of their memory problems
head-turning sign = turn to family member because they do not know answer/require verification
how does Alzheimer’s disease pathologically progress?
amyloid plaque levels increase (amyloid PET) = indicative of Alzheimer’s
tau levels increase = neuronal injury and dysfunction
neurodegeneration + cognitive impairment
what is characteristic of dementia with Lewy bodies?
fluctuating cognition!
visual hallucinations
may have REM sleeping disorder
development of symptoms associated with Parkinson’s = increased risk of falls
briefly explain the pathophysiology of Lewy body dementia
aggregation of alpha synuclein = deposition of Lewy bodies
= symptoms
what are the classic signs of frontotemporal dementia?
family history of FTLD
speech disturbances
behavioural disturbances
agitation
