Alzheimer’s Disease Flashcards
Aetiology
50-75% of cases
The pathological features include atrophy of the cerebral cortex and formation of amyloid plaques and neurofibrillary tangles.
Atrophy of the hippocampus first, then temporal and parietal lobes later
ACh production in affected neurones is reduced
Age is the biggest risk factors
Genetics (8% of risk; 92% sporadic) – genes: APEN, APP, ApoE, etc.
Presenilin 1 gene (Chr14)
Presenilin 2 gene (Chr1)
Beta-amyloid precursor protein (APP) gene (Chr21)
Co-existent Down’s syndrome increases risk
Early onset = < 65 years
F > M
Symptoms
- Early impairment of episodic memory
- Memory loss for recent events
- Repeated questioning
- Difficulty learning new information
Amnesia- recent memories are lost first, disorientation occurs early
Aphasia- word-finding problems occur, speech can become muddled and disjointed
Agnosia- recognition problems e.g. faces (prosopagnosia)
Apraxia- inability to carry out skilled tasks despite normal motor function e.g. dressing
The personality may erode as these features progress
May have delusions
Think of it as there are gaps in memory so persecutory delusions to fill in the gaps
Other -> BPSD = mood change, abnormal behaviour, hallucinations/delusions
- Psychiatric presentations delusions (15%), depression (20%), GAD
- Do not use antipsychotics to manage long-term (Risperidone has a short-term licence)
- Behavioural disturbances aggression, wandering, sexual disinhibition, explosive temper
N.B. not a true Wernicke’s aphasia as these aphasias are defined as aphasias without disturbance of intellect
N.B. patients with only depression may do badly on the MMSE = ‘depressive pseudodementia’
S/S: deficits in memory, deficits in executive function, deficits in speech and language
Recent and long-past events (Alzheimer’s = just early), patchy and specific memory loss (all early)
Management
Mild-moderate
1st Line: Acetylcholinesterase inhibitors (AChEi)
- Donepezil, Galantamine, Rivastigmine
- Used for symptomatic relief
- No effect on progression of dementia
SE: GI (N&V, diarrhoea, anorexia), other (fatigue, dizziness, headache)
- Absolute contraindications – anticholinergics (block ACh from binding), beta-blockers, NSAIDs, muscle relaxants
- Relative contraindications – asthma, COPD, GI disease, bradycardia, sick sinus syndrome, AV block
2nd Line: Memantine(if intolerant to or AChEi contraindicated)
Monitor kidney function (cautious is EGFR is on lower side)
Severe
1st Line: Memantine (NMDA antagonist)
Phycological
- 1st line: Structural group cognitive stimulation sessions (mild to moderate AD)
- Exclude depression or GAD
- Other: group reminiscence therapy, validation (reassure) therapy, multisensory therapy (improve other senses)
Social
- Explain diagnosis (and signpost support) “AD causes dementia which describes a set of symptoms including memory loss and difficulties with thinking, problem-solving or language. AD is a physical disease that affects the brain”
- Optimise health in other areas (i.e. hearing à hearing aids, visual à glasses)
- Identify future wishes (i.e. advanced directives, lasting power of attorney)
- FOLLOW-UP (every 6 months): with yourself and a single named care manager (with a clearly defined care plan)
- GENERAL: always wear ID, Dossett boxes, change gas to electricity, assistive technology in the house
- CARERS: identify and support any carers involved (signpost information and support; carer’s assessment)
- SOCIAL SUPPORT: personal care support, meal support, day centre availability
- Legally required to inform DVLA and insurers (if diagnosed with any form of dementia; MCI does not need to inform DVLA)
- Outcome -> renew licence each year, revoked licence, maintain licence
Outline the use of anticholinergic medications
Anticholinesterases (raise the ACh available) check *:
1st -> ECG
o Side effects – GI (N&V, diarrhoea, anorexia), other (fatigue, dizziness, headache)
o Absolute contraindications – anticholinergics (block ACh from binding), beta-blockers, NSAIDs, muscle relaxants
o Relative contraindications – asthma, COPD, GI disease, bradycardia, sick sinus syndrome, AV block
