Dementia syndromes Flashcards
Define dementia
A progressive, irreversible syndrome characterised by an extensive deterioration in cognition. Results in behavioural problems and impairment in daily living. Affects multiple domains of intellectual functioning.
Differentials to a diagnosis of dementia?
(these are important as they are often treatable!!)
Hypothyroidism
Addison’s
B12/folate/thiamine deficiency
Syphillis
Brain tumour
Normal pressure hydrocephalus
Subdural haematoma
Depression
Chronic drug use
Delirium
Risk factors for Alzheimer’s disease?
Increasing age
FHx
Caucasian ethnicity
Down’s syndrome
Autosomal dominant trait - e.g. mutation in amyloid precursor protein, presenilin 1 and presenilin 2.
Pathophysiology of Alzheimer’s disease?
- Global atrophy of the brain lobes - frontal, parietal, and temporal. Atrophy involves cortex and hippocampus.
- cortical plaques
—> due to deposition of amyloid protein and..
—> due to neurofibrillary tangles bc of abnormal aggregation of tau protein. - hyperphosphorylation of the tau protein.
Clinical presentation of Alzheimer’s disease?
The 4A’s:
- Amnesia (recent memory loss first)
- Aphasia (hard to find words, speech muddled and disjointed)
- Agnosia (hard to recognise things/recognition problem).
- Apraxia (can’t carry out skilled tasks even though their motor function is normal)
Management of Alzheimer’s disease?
Non-pharmacological:
- promote wellbeing
- cognitive stimulation therapy
- OT
- community/group therapy
- ID bracelets
Pharmacological:
- acetylcholinesterase inhibitors = donepezil, galantamine, rivastigmine
- NMDA receptor antagonist = memantine (second line to 1st one)
- antidepressants
- antipsychotics (only for pts who harm themselves or others/ have hallucinations or delusions).
Presentation of vascular dementia?
Hx - several months/yrs of sudden or stepwise deterioration of cognitive function.
—> note: progression varies amongst pts
Focal neuro abnormalities - visual disturbances, sensory or motor symptoms
Poor concentration
Poor attention
Memory disturbances
Seizures
Gait disturbances
Speech disturbances
Emotional disturbances - apathy, disinhibition
May also have Sx of Alzheimer’s dementia
Pathophysiology of vascular dementia?
- Reduced blood flow to the brain due to intracranial vascular pathologies = infarction
- white matter disease called subcortical leukoencepalopathy = Leukoaraiosis
- Haemorrhage
- Vascular risk factors = Alzheimers disease
Management of vascular dementia?
General management:
- mainly symptomatic, providing support to patient and carers
- detect and address CVS risk factors —> may need BP control, statins, lifestyle modifications, anticoagulation, DM control, carotid endarectomy if carotid stenosis >70%.
Non-pharmacological management:
- cognitive stimulation programme
- music and art therapy
- multi sensory stimulation
Pharmacological management:
- ACh esterase inhibitor if have Alzheimer’s as well.
How is Dx of vascular dementia made?
NINDS_AIREN criteria for probable vascular dementia
In summary:
- need comprehensive Hx and physical exam: to show presence of cognitive decline that interferes with daily living
- need formal screen for cognitive impairment and a medical review to exclude meds causing cognitive decline
- need brain imaging (MRI scan) or neurological signs that show cerebrovascular disease
- additional things:
—> onset of dementia within 3 months of recognised stroke
—> abrupt deterioration in cognitive function
—> fluctuating, stepwise progression of cognitive deficits
How is Dx of vascular dementia made?
NINDS_AIREN criteria for probable vascular dementia
In summary:
- need comprehensive Hx and physical exam: to show presence of cognitive decline that interferes with daily living
- need formal screen for cognitive impairment and a medical review to exclude meds causing cognitive decline
- need brain imaging (MRI scan) or neurological signs that show cerebrovascular disease
- additional things:
—> onset of dementia within 3 months of recognised stroke
—> abrupt deterioration in cognitive function
—> fluctuating, stepwise progression of cognitive deficits
Presentation of Lewy body dementia?
Three core features:
1. fluctuating cognition
2. parkinsonism
3. visual hallucinations
Cognitive impairment is progressive.
Where are lewy bodies found in LB dementia?
In the substantia nigra, paralimbic areas, neocortical areas.
Where are lewy bodies found in LB dementia?
In the substantia nigra, paralimbic areas, neocortical areas.
How is Lewy body dementia diagnosed?
- Clinical Dx
- Single-photon emission computed tomography (SPECT) aka DaTscan - dopamine uptake scanning.
