Dementia Flashcards
Cognition
The mental action of acquiring knowledge and understanding through thought, experience and the senses
What does cognition ecompass
Attention Language ( comprehension and production) Social functioning (judgement, evaluation and reasoning) Executive functioning (problem solving/decision making) Formation of knowledge and memory
Define dementia
Undoing of the mind
What is the DSM criteria for dementia
- evidence of significant cognitive decline in at least 1 cognitive domain (Attention, executive, learning and memory, language, perception-motor (ie praxis ) or social cognition PLUS: the cognitive deficits interfere with independence in everyday activities PLUS: they are not better explained by another process
What are the three mechanisms of acute cognitive disorders
- Viral encephalitis - Head injury - Stroke
Describe the effects of viral encephalitis
Memory, behaviour change and language
Describe the effects of head injury
Attention, memory, executive dysfunction
What are the clinical features of transient global amnesia
abrupt onset antegrade > retrograde amnesia (repetitive). Preserved knowledge of self Transient 4-6 hours (always <24 hours) Generally once off (c6% may recur)
Who is typically affected by transient global amnesia?
> 50 y/o generally 70s
What are the triggering factors of transient global amnesia
emotion/changes in temperature
What is the pathophysiology of transient global amnesia
Uncertain Transient changes in hippocampus
What are the clinical features of transient epileptic amnesia?
Forgetful/repetitive questioning Can carry out complex activities with no recollection of events Short lived (20-30 minutes)
What is transient epileptic amnesia associated with?
Associated with temporal lobe seizures - 30% seizures not witnessed - Response to anti-epileptic medication should be seen
What is the differential diagnosis for sub-acute cognitive disorders
- Toxins (alcohol, carbon monoxide) - Neurodegeneration (CJD) -Metabolic (B12, calcium, thyroid) - Inflammatory: limbic encephalitis - mood disorders - functional - Infection: HIV syphillis
What are the clinical features of sub-acute cognitive disorders?
Everyday forgetfulness impacting on functioning
What is pathognomic of subjective cognitive impairment?
Fluctuation of symptoms Mismatch between: symptoms and reported function / symptoms + symptoms of known neurodegenerative disorders
What may subjective cognitive impairment be a part of?
Generalised functional disorder (reduced concentration/attention/reaction time and subsequent memory difficulties)
What is the treatment for subjective cognitive impairment
Exclude a mood disorder (deficits in attention, executive function, and memory can be seen) plus neuropsychology
What is the most common human prion disease?
Creutzfeldt-Jakob disease
What is CJD?
Neurodegenerative proteinopathy
What are the four kinds of CJD?
Sporadic Variant Iatrogenic Genetic
_____ CJD presents at age 60 _____ CJD presents at age 20 _____ CJD presents at age 30 _____ CJD presents at any age
sporadic CJD presents at age 60 variant CJD presents at age 20 iatrogenic CJD presents at age 30 genetic CJD presents at any age
What are the clinical features of sporadic CJD?
Rapid onset dementia + neurological signs + myoclonus
What is the duration of illness of sporadic CJD?
4 months
What is the commonest form of CJD?
Sporadic
What causes sporadic CJD?
- ? erroneous production of PrPSc
- ? Somatic mutation of PRNP
- ? exposure to unidentified source
What are the clinical features of variant CJD?
Painful sensory disturbance + neuropsychiatric decline
What is the duration of illness of variant CJD?
14 months
What causes variant CJD?
Exposure to BSE (Bovine spongiform encephalopathy) (or comnaminate d blood)
What are the clinical features of iatrogenic CJD?
Cerebellar/visual onset
Multifocal neurological decline
What is the duration of iatrogenic CJD?
< 2 years
What causes iatrogenic CJD?
99% hGH+ dura mater
What are the clinical features of genetic CJD?
May mimic sporatic CJD
Specific subtypes;
- GSS (prolonged ataxic syndrome)
- FFI (insomnia)
What is the duration and cause of genetic CJD?
Variable <2 years
Mutation of PRNP
What is alzheimers disease?
Neurodegenerative proteinopathy
Describe the pathogenesis of alzheimer’s disease?
Disruption of cholinergic pathways in the brain + synaptic loss: extracellular amyloid plaques (? disrupts normal cell function/ induces apoptosis)
Intracellular neurofibrillary tangles (?disruption of cytoskeleton -> cell death)
Why do symptoms progress from forgetfulness in alzheimers disease?
Degeneration of medial hippocampus + later parietal lobes: forgetfulness -> apraxia/visuospatial difficulties
What age defines early onset alzheimers
65
What are the atypical presentations of alzheimers disease?
Posterior cortical atrophy
- visuospatial disturbance
- commonly referred from ophthalmology
Progressive primary aphasia
- semantic (naming)
- logopenic aphasia (repeating)
- non-fluent aphasia (effortful)
What are the investigations for alzheimers disease?
MRI: atrophy of temporal/parietal lobes
SPECT: temporoparietal (decreased metabolism)
CSF: Decreased amyloid : increased tau ratio
Research: amyloid ligand imaging
What is the treatment for alzheimers disease?
Address vascular risk factors
Acetylcholine boosting Rx
- cholinesterase inhibitors (eg rivastigmine/galantamine)
- NMDA receptor blocker (eg memantine)
What is frontotemporal dementia?
early onset dementia <65 years old
Neurodegenerative proteinopathy
What is the pathophysiology of frontotemporal dementia?
Tau > TDP-43 > ubiquitin
Protein aggregation –> cell damage
What are the early frontal features of frontotemporal dementia?
- disinhibition, apathy, loss of empathy, stereotyped or compulsive behaviours, hyperorality)
- early loss of insight (collateral history vital)
What are the investigations for frontotemporal dementia?
MRI: atrophy of frontotemporal lobes
SPECT: frontotemporal decreased metabolism
CSF: increased tau/normal amyloid
What is the treatment for frontotemporal dementia?
Trial of trazadone/antipsychotics to help behavioural features
Describe unique features of management of FTD?
Safety management
- controlled access to food/money/internet
- structured activities
Power of attorney
- support: MND nurse specialise if co-existent MND/CPN
Vascular dementia is typically a ___ onset dementa (>__years old)
The core criteria are (2)
Vascular dementia is typically a late onset dementa (>65 years old)
The core criteria are;
- Presence of cerebrovascular disease
- A clear temporal relationship between the onset of dementia and cerebrovascular disease
What are the different presentations of vascular dementia
Subcortical
Post-stroke dementia
What is subcortical vascular dementia?
Small vessel disease: decreased attention, excecutive dysfunction and slowed processing
What may occur alongside vascular dementia
Co-existent amyloid pathology
What is the management of vascular dementia?
Vascular risk factors +/- cholinesterase inhibitor
CPN
Dementia with Lewy bodies is a ____ onset dementia (majority >__yrs)
It is also neurodegenerative proteinopathy;
_-_____ aggregates = insoluble -> cell ______ -> cell _____
Leads to disruption of ______ and _________ pathways
Dementia with Lewy bodies is a late onset dementia (majority >65 yrs)
It is also neurodegenerative proteinopathy;
alpha-synuclein aggregates = insoluble -> cell dysfunction -> cell damage
Leads to disruption of cholinergic and dopaminergic pathways
What are the core criteria of dementia with lewy bodies?
1) Fluctuating cognition
2) recurrent well-formed visual hallucinations
+/- 3) presence of extrapyramidal features (75%)
Additional: neuroleptic sensitivity
What are the investigations for dementia with lewy bodies?
DaT (dopamine transporter imaging)
New (research) techniques: alpha-synuclein ligand imaging / alpha- synuclein in CSF
What is the treatment for dementia with Lewy bodies?
Small dose levodopa / decreased acetylcholine (amongst other neurotransmitters) -> trial cholinesterase inhibitors
What is parkinsons disease dementia?
Late onset dementia (>65 years old)
80% Develop dementia after 20 years of PD
DLB __ year of presentation
PDD __ year of presentation
DLB <1 year of presentation
PDD >1 year of presentation
What is the management of PDD?
The same as DLB
Huntington’s disease is an _____ onset dementia (mean age of onset is __-__ years)
Huntington’s disease is an early onset dementia (mean age of onset is 30-50 years)
What causes huntingtons disease?
Expanison of the CAG trinucleotide repeat on the huntingin gene - produces neurodegenerative protein huntingtin
Describe huntingtons dementia
Dysexecutive syndrome + slowed speed of processing
Eventual involvement of memory
Associated changes in mood/personality, and chorea +/- psychosis
What are the investigations for HD?
Genetic testing
MRI- loss of caudate heads
What are the treatment options for HD?
Mood stabilisers
Rx for chorea
HD nurse specialist
- Referral?
1 ) >65 years old gradual onset dementias / no additional neurology
2 ) <65 years old / any unusual features (including speed of onset) / additional neurology
- old age psychiatry
- neurology
what history is taken in neurology memory clinic?
History from patient
Collateral history: What were the first deficits; what has happened since then; what are their functional difficulties
What cognitive assesement is undergone in neurology memory clinic?
Addenbrooke’s cognitive assessment
What imaging is done in neurology memory clinic?
MRI (patterns of atrophy)
SPECT
What bloods are taken in neurology memory clinic?
‘Dementia screen’ – B12, TFTs, syphilis, HIV, Ca2+ etc(+/- genetic panel)
What is done in neuropsyhcology at neurology memory clinic?
more in depth assessment of deficits / strengths (for management strategies)
What is checked for in CSF in neurology memory clinic?
Amyloid/tau/+/- prion
