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.
How is Lewy body dementia managed?
Acetylcholinesterase inhibitors and memantine can be used.
Carbidopa/Levodopa if motor symptoms are present and severe
What condition is Lewy body dementia associated with?
Parkinson’s disease
What medication should be avoided in Lewy body dementia, and why?
Neuroleptics
Why? patients are v sensitive to this, can cause deterioration in Parkinsonism / develop irreversible Parkinsonism. Obvs not v good.
Presentation of frontotemporal dementia?
Onset before 65yrs - peaks in mid 50s
Insidious/gradual onset
Personality change and problems with social conduct
Memory and visuospatial skills are preserved
Progressive loss of language fluency
FHx
Altered eating habits
Behaviours that can be classified in frontotemporal dementia?
Apathetic
Disinhibited
Stereotypic - which is a mix of apathetic and disinhibited
Pathophysiology of frontotemporal dementia?
Focal neurodegeneration of frontal and temporal lobes of brain
Get Pick bodies = spherical aggregations of tau proteins.
Management of frontotemporal dementia?
Depends on pt needs:
Irritable, restless, agitated or aggressive = benzodiazepines
Compulsions = SSRIs
Sleeping disturbances = Mirtazapine
Distracted = Amantadine
Gluttony = Topiramate
Home assistance and respite care.
Presentation of semantic dementia?
This is a type of frontotemporal lobar degeneration.
Fluent progressive aphasia
—> speech is fluent but empty, doesn’t have much meaning.
Memory is better for recent events than past events.
Presentation of AIDS dementia complex?
Insidious onset, but once started, progression is rapid.
Behavioural changes
Motor impairment
Pathophysiology of AIDS dementia complex?
HIV virus - infected macrophages enter the brain —> cause indirect damage to neurones.
How is AIDS dementia complex investigated?
CT scan of brain
What is found on CT scan of brain with AIDS dementia complex?
Cortial and subcortical atrophy
Investigations to do for pt with suspected dementia?
Mini mental state exam
Dementia screen:
- FBC
- U&Es
- TSH
- Serum vitamin B12
Urine drug screen
CT head
MRI brain
ECG in vascular dementia
Why do we take FBC of patient with symptoms of suspected dementia?
Look for anaemia
Why do we take U&Es of patient with symptoms of suspected dementia?
Look for any deranged sodium, calcium etc
Why do we take TSH of patient with symptoms of suspected dementia?
Look for hyperthyroidism / hypothyroidism
Dementia vs delirium:
Onset?
Daily course?
Length?
Consciousness?
Alertness?
Activity?
Attention?
Orientation?
Dementia:
Onset = slow and insidious
Daily course = stable
Length = years
Consciousness = conscious
Alertness = normal
Activity = variable
Attention = normal
Orientation = impaired
Delirium
Onset = abrupt
Daily course = fluctuates in day
Length = hours to weeks
Consciousness = fluctuates
Alertness = increased or decreased
Activity = increased or decreased
Attention = impaired
Orientation = impaired
Dementia vs depression:
Onset?
Daily course?
Length?
Consciousness?
Alertness?
Activity?
Attention?
Orientation?
Dementia:
Onset = slow and insidious
Daily course = stable throughout day / no fluctuation
Length = years
Consciousness = conscious
Alertness = normal
Activity = variable
Attention = normal
Orientation = impaired
Depression:
Onset = variable
Daily course = stable throughout day / no fluctuation
Length = variable
Consciousness = conscious
Alertness = normal
Activity = variabl
Attention = normal
Orientation = normal
Name a reversible cause of cognitive decline
quesmed
vitamin B12 deficiency, hypothyroidism, hypercalcaemia, niacin deficiency, neurosyphilis, normal pressure hydrocephalus, subdural haematoma, delirium
Alzheimers : What needs to be done before cholinesterase inhibitors can be prescribed? one investigation and questions
capsule case: Psych 609
Do:
* ECG
AsK:
* Hx of peptic ulcer disease / dyspepsia
* hx of asthma
* cardiac history - arrythmias
* discuss risks and benefits with pt / carer
* discuss likelihood of compliance
