PBL 45 Flashcards
What are the 5 most common subtypes of dementia?
- Alzheimer’s disease
- Vascular dementia
- Dementia with Lewy bodies
- Frontotemporal dementia
- Mixed dementia
Dementia vs mild cognitive impairment?
MCI = symptoms worse than affected for their age BUT ADLs are not affected
Dementia = The symptoms must have become bad enough to significantly affect the person’s ADL
Symptoms of dementia
- Memory problems
- Retention of new information
- Forget names
- Lost in prev. familiar places - Impairments in cognitive abilities
- Disorientation in time and place
- Concentration
- Reasoning and decision-making skills - Impairments in communication
- Repetitive
- Reading and writing
- Following and engaging in conversation - Changes in behaviour/personality
- Mood swings
- Anxiety/depression
- Lose interest in seeing others socially –> Isolation/withdrawal
Pathophysiology of Alzheimer’s disease
Physical changes in the structure of the brain:
- Amyloid plaques
- Amyloid protein protects neurons from calcium influx and over-excitation by glutamate
- Abnormal amyloid protein allows calcium influx and neuronal cell death
- Abnormal amyloid protein processing allows a build up of BETA-amyloid which is laid down in neurons and deposited as plaques, these plaques lead to further inflammatory response which leads to further cell death and disruption to function - Tau - neurofibrillary tangles
- Tau protein helps brain cells communicate with each other
- Hyperphosphorylated tau leads to a build-up of tau protein which causes tangles, this makes the cells less able to communicate with each other - Reduced acetylcholine
- Leads to information less likely to be transmitted, or not at all
Which of the general symptoms of dementia are more common in Alzheimer’s?
Memory lapses due to hippocampal changes (STM), these also lead to disorientation in time and place, or not being able to recognise familiar faces and objects
Risk factors for Alzheimer’s disease
- Age - >65y/o
- Sex - Women > men
- Genetics - RARE
- Poor physical health - Inadequately controlled heart disease or diabetes
- Lifestyle choices - smoking, lack of exercise, Xs alcohol use
What has to be ruled out when diagnosing Alzheimer’s?
- Vitamin B-12 deficiency
- Underactive thyroid gland
Prevention of Alzheimer’s?
- Regular health checks with GP
- Keep on top of physical health conditions
- Mediterranean diet
- Have BP, weight and cholesterol regularly checked
First line treatment for Alzheimer’s? MoA, side effects and contraindications
ACETYLCHOLINESTERASE INHIBITORS
- Donepezil / Rivastigmine / galantamine
MoA: Reduce breakdown of Ach in synaptic cleft to support cell communication
Side effects: GI = Nausea, vomiting, diarrhoea
Contraindications: Asthma/COPD, seizures, arrhythmias
Alternative treatment for Alzheimer’s disease (behavioural symptoms). Side effects and contraindications?
MEMANTINE
Side effects: sleepiness, sedation, dizziness, headache, constipation, SOB
Contraindications: Seizures
MoA of memantine
NMDA (glutamate) receptor antagonist
What is vascular dementia?
An umbrella term for a group of conditions caused by problems with blood circulation to the brain
Pathophysiology of vascular dementia
- TIAs - prevent O2 reaching brain tissue
- Atherosclerosis - blocked arteries
- Haemorrhage
Signs and symptoms of vascular dementia (different to Alzheimer’s)
- Confusion
- Agitation
- Depression
- Unsteady gait
- Memory problems
- Urinary frequency, urgency and incontinence
- Night wandering
- Decline in ability to organise thoughts/actions, difficulty organising
- Poor attention & concentration
Risk factors for vascular dementia
- Age - >65y/o
- Sex - Men>women
- FHx - Stroke, diabetes, CV disease
- Poor physical health - Inadequately controlled CV disease, diabetes, hypertension, hypercholesterolaemia
- Lifestyle choices - Smoking, Xs alcohol use, lack of exercise
Treatment for vascular dementia
INFARCT DAMAGE CANNOT BE REVERSED
- Manage/control the risk factors!
- Manage physical conditions (diabetes, blood pressure, hypercholesterolaemia, weight)
- Mediterranean diet
- Lifestyle changes - stop smoking, less alcohol use, weight reduction/exercise
Pathophysiology of dementia with Lewy bodies (DLB)
Build-up of clumps of proteins called Lewy bodies in nerve cells, this disrupts how cells communicate with each other
Lewy bodies are also linked to a decrease in certain chemicals, particularly acetylcholine and dopamine, causing a loss of connection between nerve cells
What are Lewy bodies?
A build-up of alpha synuclein protein which are deposited in nerve cells
Signs and symptoms of DLB
Depends where the Lewy bodies have accumulated within the brain
- Those found at the base of the brain have been linked to PARKINSONIAN features = slowed movement, stiffness, tremors
- Increased falls
- Well-formed hallucinations
- Delusions
- Early visuospatial awareness problems
- General dementia symptoms: mood changes, memory problems, fluctuating alertness / confusion / concentration levels, problem solving skills decline
Risk factors for DLB
- Age - >65y/o
- Sex - EQUALLY men and women
- Genetics - RARE
A diagnosis of DLB requires a progressive decline in your ability to think and at least two of what?
- Fluctuating alertness and thinking function
- Repeated visual hallucinations
- Parkinsonian features
- REM sleep behaviour disorder - where people act out their dreams during sleep
Treatment/management for DLB
There is NO SPECIFIC treatment
- Hearing and sight problems make delusions and hallucinations worse, so tend to these!
- Sleep problems can be an issue, so reduce caffeine & alcohol intake later in the afternoon, keep bedroom at a comfortable temperature and reduce unnecessary stimuli
- Can use acetylcholinesterase inhibitors for memory/attention/hallucination problems
- PARKINSON’S DISEASE MEDICATION - L-dopa for the Parkinsonian symptoms however this can increase confusion, hallucinations and delusions
What are the 3 variants of frontotemporal dementia?
- Behavioural variant frontotemporal aphasia (Pick’s disease)
- Primary progressive aphasia = semantic dementia and progressive non-fluent aphasia
Pathophysiology of frontotemporal dementia
Occurs when nerve cells in the frontal or temporal brain lobes die
- This causes chemical messengers which transmit signals between these two lobes to be lost, so over time there is more and more cell death, causing the volume of the brain tissue in the frontal and temporal lobe to shrink!
- ASSOCIATED WITH MUTATION IN TAU GENE
Signs and symptoms of frontotemporal dementia (behavioural variant)
- Changes in personality and behaviour –> lose inhibitions
- Apathy and withdrawal
- Obsessive or repetitive behaviour
- Loss of empathy, emotional blunting
- Changes in appetite and food eaten –> hyperorality
- Difficulties with decision making, problem solving and concentration
Signs and symptoms of frontotemporal dementia (primary progressive aphasia)
- Language difficulties
- Speech
- Grammar problems
- Reduced comprehension
- Loss of understanding of familiar words
- Difficulty recognising people or objects
Risk factors for frontotemporal dementia
- Sports where you are constantly being hit in the head
- Age - <65y/o
- Sex - Men and women equally
- Genetics - 1/3 cases may be familial
What are the principal classes of anaesthetic drugs?
- General anaesthesia
- Local anaesthetic agents
- Neuromuscular blocking drugs
- Analgesia