Dementia Flashcards
What are the 4 main types of dementia from most - least common
- Alzheimer’s disease
- Vascular dementia
- Lewy body dementia
- Frontotemporal dementia
How is dementia generally investigated
- Primary care: blood screen to exclude reversible cause - FBC, U&Es, LFTs, Calcium, glucose, ESR/CRP, TFTs, vitamin B12 and folate levels
- Secondary care: neuroimaging
What cognitive assessments may be done in the assessment of dementia
- mini mental state exam
- 6-Item cognitive impairment test (6CIT)
- Montreal cognitive assessment scale
Give some differentials to dementia
- hypothyroidism
- B12/folate/thiamine deficiency
- syphilis
- brain tumour
- normal pressure hydrocephalus
- subdural haematoma
- depression
What is Alzheimer’s disease
a progressive degenerative disease of the brain accounting for the majority of dementia seen in the UK
Give 5 RFs for alzheimer’s disease
- increasing age
- FHx
- Genetics
- Down’s syndrome
- apoprotein E allele E4
- Cerebrovascular disease
What mutations are thought to cause the inherited form of Alzheimer’s disease
- amyloid precursor protein (chromosome 21)
- presenilin 1 (chromosome 14) genes
- presenilin 2 (chromosome 1) genes
Describe the pathological changes that occur in Alzheimer’s disease
- macroscopic: widespread cerebral atrophy, particularly involving the cortex and hippocampus
microscopic: - cortical plaques due to deposition of type A-Beta-amyloid protein (extracellular)
- intraneuronal neurofibrillary tangles caused by abnormal aggregation of the tau protein (intracellular)
- hyperphosphorylation of the tau protein has been linked to AD
Describe the features of Alzheimer’s disease
- insidious onset and progressive but slow decline
- cognitive impairment: poor memory, receptive/ expressive dysphasia, disorientation
- behavioural and psychological changes: agitation, depression, sleep cycle disturbance, disinhibition, wandering
- activities of daily living: loss of independence, problems with finances, problems with basic personal care
Describe the non-pharmacological management of Alzheimer’s disease
- range of activities to promote wellbeing that are tailored to the person’s preference
- group cognitive stimulation therapy for patients with mild and moderate dementia
- exercise
Describe the pharmacological management of Alzheimer’s disease
- mild to moderate: acetylcholinesterase inhibitors (donepezil, galantamine and rivastigmine)
- moderate-severe: NMDA receptor antagonist (memantine) +/- acetylcholinesterase inhibitors
- memantine monotherapy if severe AD or intolerant/ CI to Achesterase inhibitors
Which acetylcholinesterase inhibitor is best for hallucinations
rivastigmine
How are psychiatric symptoms managed in dementia
- antidepressants aren’t recommended for mild to moderate depression in patients with dementia
- antipsychotics should only be used for patients at risk of harming themselves or others or when symptoms are causing severe distress
- antipsychotics are associated with a significant increase in mortality in dementia patients
What is vascular dementia
a group of syndromes of cognitive impairment caused by different mechanisms causing ischaemia or haemorrhage secondary to cerebrovascular disease
What are the three main subtypes of vascular dementia
- Stroke-related VD - multi-infarct or single-infarct dementia
- Subcortical VD - caused by small vessel disease
- Mixed dementia - the presence of both VD and Alzheimer’s disease
Describe the presentation of vascular dementia
- symptoms of dementia appear suddenly and there’s a stepwise deterioration pf cognitive function
- focal neurological abnormalities - aphasia, weakness
- difficulty with attention and concentration
- Seizures
- Memory/ gait/ speech/ emotional disturbance
How is vascular dementia investigated
- Blood screen
- neuropsychological tests
- CT/MRI - may show infarcts and extensive white matter changes
Describe the non-pharmacological management of vascular dementia
Tailored to the individual
* Include: cognitive stimulation programmes, multisensory stimulation, music and art therapy, animal-assisted therapy
* Managing challenging behaviours e.g. address pain, avoid overcrowding, clear communication
Describe the pharmacological management of vascular dementia
- only consider AChE inhibitors or memantine if there’s mixed dementia
- no specific pharmacological treatment approved for cognitive symptoms
- detect and address cardiovascular risk factors
Describe the pathological changes that occur in Lewy body dementia
- misfolded alpha synuclein protein aggregates to form Lewy bodies that deposit inside neurones, particularly in the neocortex and basal ganglia
- Lewy bodies lead to reduced levels of ACh and dopamine in the brain
Describe the features of Lewy body dementia
- Early: progressive cognitive impairment
- fluctuating cognition
- visual hallucinations
- Later: parkinsonism - typically occur within a year of onset of cognitive impairment
How is Lewy body dementia diagnosed
- usually clinical
- blood screen - exclude other causes
- single-photon emission computed tomography (SPECT)
How is Lewy body dementia managed
- AChE inhibitors and memantine
- avoid neuroleptics - can cause irreversible parkinsonism
What are the common features of frontotemporal dementias
- onset before 65
- insidious onset
- Relatively preserved memory and visuospatial skills
- Personality change and social conduct problems (compulsive behaviour, abnormal eating etc)
Describe the pathological changes seen in frontotemporal dementia
- Macroscopic: Atrophy of the frontal and temporal lobes
- Microscopic: Pick bodies - spherical aggregations of tau protein
How is frontotemporal dementia managed
- no cure or way to slow down progression
- non-pharmacological: exercise, SALT
- pharmacological: SSRIs - decrease disinhibition and impulsivity
(AChE inhibitors/ memantine not recommend)
Give 5 factors that would suggest a diagnosis of depression over dementia
- short history, rapid onset
- biological symptoms: weight loss, sleep disturbance
- relatively normal mini mental state test
- will answer ‘I don’t know’ as opposed to trying to give an answer
- global memory loss
