Dementia Flashcards
What is dementia?
Acquired, chronic + progressive cognitive impairment which results in impairment of ADLs
What are the primary and secondary dementia?
Primary: Alzheimers, Lewy body, Frontotemporal, Vascular
Secondary: Deficiencies (B12, Thiamine), Dehydration, Infection (Syphilis)
What are 8 risk factors for Alzheimers dementia?
Age
Female
FH
Vascular RFs
Low IQ/ education
Head injury
Previous depression
Down syndrome
Summarise the epidemiology of dementia.
5% of >65s
20% of > 80s.
What are the signs and symptoms of dementia?
Most commonly affected areas inc. memory, visual-spatial, language, attention + problem solving.
Most types of dementia are slow + progressive.
- Memory impairment
- Anxiety/ Depression
- Mood changes: Agitation/ Irritability
- Speech abnormalities
- Disinhibition + impulsivity
- Delusions (often believing people are stealing from them) or hallucinations
- Changes in sleep or appetite.
What investigations would you do for dementia?
Bloods: r/o other causes
FBC + B12 + folate
U+Es: uraemia, renal failure
Alcohol hx + LFTs
Syphilis + HIV testing
TFTs
Refer to memory clinic
Hx + collateral
Cognitive testing
Brain MRI/ CT: shows degeneration
What are the main types of dementia?
Alzheimer’s: 50-80%
Vascular: 20-30%
Lewy Body: 10-25%
Frontotemporal: 10-15%
How does Alzheimer’s Dementia present?
Amnesia: Memory loss, esp. recent events
Aphasia: Language deficits
Agnosia: difficulty recognising things/ faces
Apraxia: Impaired visuospatial skills
Gradual progressive onset
How does Alzheimer’s Dementia present on imaging?
Cortical atrophy (esp. medial temporal + parietal)
Beta amyloid plaques
Neurofibrillary tangles
How does vascular dementia present?
Abrupt or gradual onset
Patchy cognitive impairment
Focal neurological signs
Signs of vascular disease
How does vascular dementia present on imaging?
Multiple white matter lucencies
Atrophy
Strokes
Lacunar infarcts
How does Lewy Body dementia present?
Fluctuating cognition + consciousness
Visual hallucinations
Parkinsonism
Neuroleptic sensitivity
Autonomic instability (syncope)
Recurrent Falls
How does Lewy Body dementia present on imaging?
Generalised atrophy
Lewy bodies in cortex + midbrain
How does frontotemporal dementia present?
- Insidious onset, typically in 50-60s, rapid progression
- Disinhibition
- Socially inappropriate behaviour
- Poor judgement
- Apathy, decreased motivation
- Poor executive function
How does frontotemporal dementia present on imaging?
- Frontal + temporal atrophy
- Pick cells + pick bodies in cortex
What causes the cognitive symptoms seen in Alzheimers?
Reduced levels of Acetylcholine
What is the pharmacological treatment for Alzheimers dementia?
Cholinesterase inhibitor: Donepezil, Rivastigmine
NMDA antagonists: Memantine (severe)
What is the pharmacological treatment for Vascular dementia?
Aspirin
(to prevent further ischaemic damage)
What is the pharmacological management for frontotemporal dementia?
SSRIs help with behavioural Sx
Supportive Tx
Atypical antipsychotics
What is the management for Lewy body dementia?
Cholinesterase inhibitor: Donepezil, Rivastigmine
Clonazepam for REM sleep disturbance
Parkinson’s medication could relieve tremors but worsen psychosis
Antipsychotics are DANGEROUS, can cause confusion, Parkinsonism + death
What are the complications of dementia?
Pneumonia
Institutionalisation
UTI
Falls + their complications
Weight loss
Elder abuse
Depression
Agitation
Which genes are associated with early and late onset Alzheimers dementia?
Early: APP mutations (Chr21), Presenilin 1 + 2 mutations
Late: APOE E4 allele
List 7 risk factors for vascular dementia
Age
Male
Smoking
HTN
Diabetes
Hypercholesterolaemia
Atrial fibrillation
Which gene is associated with increased risk of Lewy body dementia?
APOE E4 allele
List 4 features contributing to pathophysiology of Alzheimers Dementia
Plaques
Neurofibrillary tangles
Cortical atrophy
Cholinergic pathway loss
How should Parkinsons disease dementia be treated?
Levodopa +/- MAO-B inhibitor or COMT inhibitors
How do plaques form in AD?
In neuronal cell membranes, APP influences cell growth + survival
When broken-down abnormally, forms insoluble extracellular plaques of B amyloid
Disrupts signalling between neurones, triggers immune mediated inflammation + damages blood vessels
How do neurofibrillary tangles form?
Plaques trigger abnormal phosphorylation of Tau
Tau usually stabilises microtubules
Phosphorylated Tau collapses into twisted strands
Disrupts cell transport + causes neuronal death
How does cortical atrophy arise in AD?
Follows neuronal loss
Hippocampus (essential for short term memory + visuospatial skills) affected early before temporal + parietal lobes
Enlarged sulk + ventricles on imaging
Which pathways are thought to be mostly affected in AD?
Cholinergic pathways
What patholophysiology is found in vascular dementia?
Arteriosclerosis
Cortical ischaemia
Cortical infarcts
How are dementia with Lewy bodies and Parkinsons disease related?
2 expressions of a shared problem in metabolising alpha-synuclein protein
Causes deposition of Lew bodies
What are Lewy bodies?
Abnormal eosinophilic intracytoplasmic neuronal structures composed of alpha synuclein with ubiquitin
How does DLB differ to PD?
PD: Lewy bodies in brainstem. Movement disorder predates cognitive Sx >,1y
DLB: Lewy bodies in cingulate gyrus + neocortex. Cognitive impairment precedes movement Sx/ occurs within 1y of their onset
Describe the presentation of variant CJF
Initially psychiatric Sx: depression, anxiety + insomnia
Later: Amnesia, ataxia + sensory neuropathy
Describe the presentation of sporadic CJD
Age of onset commonly 6-+
Presents with neurological Sx
