Dementia Flashcards
Define dementia
Progressive, irreversible clinical neurodegenerative syndrome with a range of cognitive and behavioural symptoms e.g. memory loss, problems with reasoning and communication, change in personality, and reduction in person’s ability to carry out daily activities
What are the types of dementia
Alzheimer’s (70-80%)
Vascular (17%)
Frontotemporal
Lewy body
Parkinson’s
What defines early-onset dementia
<65yo
What is the aetiology of Alzheimer’s dementia
Formation of senile b-amyloid plaques and neurofibrillary tangles, atrophy of the cerebral cortex
Amyloid: Cleavage by b-secretase (instead of a-secretase) → releases sAPPb (sAPPa) and c99 gragment (c83) → digested by y-secretase → beta-amyloid protein
Tau: hyperphosphorylated → insoluble → aggregates to form neurofibrillary tangles → microtubule instability
Inflammation: increased inflammatory mediators and cytotoxic proteins, increased phagocytosis, decreased neuroprotective
What are the risk factors for Alzheimer’s
Age (1% at 60yo, risk ~doubles every 5 years)
Prior intellectual level (low IQ) or educational level
FHx
Down’s syndrome
Genetic
- Presenilin 1 gene (Chr14)
- Presenilin 2 gene (Chr1)
- Beta-amyloid precursor protein (APP) gene (Chr21)
Cerebrovascular disease, Hyperlipidaemia, Lifestyle (smoking, obesity, high saturated fat diet, alcohol)
Traumatic brain injury
Depression
Elevated plasma homocysteine
What are the clinical features of Alzheimer’s dementia
Gradual and progressive loss in cognitive function
1. memory loss, wandering, irritability
2. 4As
3. Cognitive impairment in all domains, seizures, incontinence, loss of independence
Amnesia
- Recent memory first → loss of episodic memory (recent events, repeated questioning, difficulty with new information)
- misplacing items
- wandering and getting lost
Aphasia
- Broca’s - difficulty finding correct words
- Speech is muddled/disjointed
- Nominal dysphasia
Agnosia
- Typically a visual agnosia e.g. prosopagnosia (recognising faces)
Apraxia
- Typically difficulty with fine motor skills e.g. dressing, skilled tasks
What are the behavioural and psychological symptoms of dementia (BPSD)
Psychosis (delusions and/or hallucinations)
Agitation and emotional lability (easily upset, argumentative, shouting, mood swings)
Depression and anxiety
Withdrawal or apathy
Disinhibition (socially or sexually inappropriate behaviour)
Motor disturbance (wandering, restlessness, pacing, repetitive activity)
Sleep cycle disturbance
Tendency to repeat phrases or questions
What investigations should be done for dementias
Collateral history
Full systems exam and obs
Primary care: AMTS, MMSE, MOCA
Secondary: Community assessment form and Addenbrooke’s (ACE-III)
Bedside: BM, urine dip, urine MSU for MC&S, ECG
Bloods: FBC, U&Es, LFTs, TFTs, vitB12 & folate, thiamine, calcium, ESR/CRP, Hba1c, HIV testing and syphilis serology
Other: MRI, CT, FDG-PET
- Alzheimer’s MRI: grey matter atrophy, wide ventricles and sulci, temporal lobe atrophy
- Vascular MRI: multiple white hypodensities
- DLB: generalised atrophy
- FT: frontal and temporal atrophy
What is the management for Alzheimer’s dementia
Refer to memory clinic
MDT - Holistic care (proactive and reactive)
Bio
First line: Anticholinesterase - donepezil (aricept), galantamine, rivastigmine
Second line (1st if severe): NMDA/glutamate partial receptor agonist - memantine
Psycho
Structural group cognitive stimulation sessions
Treat co-morbid mental health conditions
Other: Group reminiscence therapy, validation therapy, multisensory therapy
Social
Education for patient and family
Signpost to resources
Optimise other areas of health e.g. vision, hearing and the environment e.g. orientating furniture, staff, dossett boxes
Occupational therapy - rails, changing gas to electric, assistive technology
Carer’s assessment
Meal support
Driving consideration
Sleep hygiene
Planning (advance decisions, LPA, preferred place, wills)
+ 6 months follow up
What are the contraindications to using anticholinesterases
Must do an ECG before starting acetylcholinesterase
Absolute contraindications:
- Anticholinergics
- Beta-blockers
- NSAIDs
- Muscle relaxants
Relative CIs: Asthma, COPD, GI disease, bradycardia, sick sinus syndrome, AV block
What is the management for patients with dementia who are at risk of harming themselves or experiencing agitation/hallucinations/delusion
De-escalation strategies
Risperidone and haloperidol
What are the side effects of anticholinesterases
GI issues e.g. Nausea, vomiting, diarrhoea, anorexia
Fatigue
Dizziness
Headache
Insomnia
Muscle cramps
What is the prognosis for Alzheimer’s dementia
Average life expectancy from diagnosis is 3-8 weeks
Good prognostic indicator: female
Bad prognostic indicator: male, depression, behavioural problems, severe focal cognitive deficit
What are the aetiology and risk factors for vascular dementia
Infarcts caused by thromboemboli or narrowing of arteries due to HTN
RF:
Age
Male
Obesity
Lack of exercise
Smoking
AF
DM
HTN
CVA history (stroke, TIA)
What are the clinical features of vascular dementia
Sudden onset (may follow CVA), stepwise deterioration
- 1st: emotional and minor personality changes (labile emotion – tearful elation)
- 2nd: cognitive deficit
Focal neurological signs (S/S reflect site of infarct) – i.e. upgoing plantars, hemiparesis, visual field defects
Gait an attention problems (subcortical ischaemic vascular)
Co-morbid depression
Relatively preserved personality e.g. in AD “mum just isn’t herself anymore” vs in VD “mum is a little different and is using her left arm much less”
