Lecture 13 - Dementia And Delirium Flashcards
What is dementia?
A chronic progresssive syndrome of insidious onset where theres progressive destruction of neurons
What are the 4 types of dementia?
Alzheimer disease
Vascular dementia
Lewy-body dementia
Frontotemporal dementia
Aids related dementia
What is thought to be the main 2 causes of Alzheimer dementia?
Formation of:
-Plaques
-Tangles
What forms the plaques in Alzheimer dementia?
Beta amyloid plaques
What forms the tangles that’s thought to cause Alzheimer Dementia?
Tau proteins
What is the pathophysiology of plaque formation in Alzheimer disease?
Amyloid precursor protein broken down by beta secretase leading tot formation of INSOLUBLE B amyloid plaques which aggregate
Normally amyloid precursor protein broken down by. Alpha and gamma secretase into soluble wastes
What is the downside to beta amyloid plaques forming in Alzheimer dementia?
Thought to induce inflammation
Neuronal death
What is thought to be the pathological process behind the formation of tangles in Alzheimer dementia?
Tau protein tangles form due to hyper phosphorylation of Tau
Likeli caused by Beta amyloid plaques
What is the normal function of Tau proteins?
They stabilise microtubules in the neuronal cytoskeleton
What are the macroscopic changes to the brain that occur during Alzheimer disease?
Which area is typically affected first?
General brain atrophy (Hippocampus is often affected first)
Narrowing of gyri
Widening of sulci
Ventricular enlargement
What neurotransmitter levels decline in Alzheimer disease and why?
Acetylcholine (ACh)
Since new memory making is impaired and ACh needed for processing memory and learning
What are the general class of drug used to try and treat Alzheimer disease and why?
Cholinesterase inhibitors (donepezil)
Help increase level of already declined ACh
What are the 3 types of Alzheimer dementia?
Sporadic
Familial
Trisomy 21 (Down syndrome linked)
What is the most common cause of Alzheimer disease?
Sporadic
What is thought to be the casuative gene in familial Alzheimer disease?
PSEN 1/2
What are the symptoms of Alzheimer disease?
Slow developing
Short term memory loss (hippocampus)
Motor and language then affected
Long term memory loss
Disorientation
Immobilisation
What is thought to be the main cause of death related to Alzheimer disease?
Death usually related to the fact that the patient is immobile
(E.g more likely to get chest infections like pneumonia and die)
How is Alzheimer dementia diagnosed?
Diagnosis of EXCLUSION
Need to be sure no other disease process can cause symptoms:
-hypothyroidism
-Hypercalcaemia
-B12 deficieny
-Delirum
CT scan
What treatment is given for advanced Alzheimer dementia and why?
Memantine
Is a glutamate receptor antagonist
Levels of glutamate increase as neurones die so memantine protects the nerve cells from the high levels of glutamate
What are some general cognitive symptoms of dementia?
What lobe would be involved with each symptom?
Impaired memory (Temporal lobe)
Impaired orientation (temporal lobe)
Impaired learning (temporal lobe)
Impaired judgement (frontal lobe)
If a patient has behavioural symptoms associated with their dementia, which lobe has likely been affected?
Frontal lobe
Sexual disinhibition
Aggression
What is the difference between visual and auditory hallucinations and persecutors delusions?
V and A hallucinations are false perceptions
Whereas
Persecutors delusions are false beliefs
What type of neurones are mainly affected in Alzheimer dementia?
CHOLINERGIC
Noradrenergic
Serotonergic
What is Lewy Body Dementia?
Dementia which then goes on to develop. Parkinsonian like symptoms
How does the speed of developmetn of Lewy Body dementia compare to the speed of onset of Alzheimer dementia?
Lewy body dementia = more rapid onset
What is thee cause of Lewy body dementia?
Misfolding of Alpha synuclein proteins
Where are alpha synuclein misfolded protiens deposited to cause the dementia type symtpoms?
Cortex
Where are alpha synuclein misfolded proteins deposited to cause parkinsonian like features?
Substantia nigra
What do the misfolded synuclein proteins aggreate to form?
Lewy bodies
What are the early cognitive symtpoms of Lewy body dementia?
Distressing hallucinations (small people and furry animals)
Depression
REM sleep disorders (sleepwalking and talking)
What are some later parkinsonian symtpoms of Lewy body dementia?
Bradkinesia
Resting tremor
Stiffness
What is the treatment for Lewy body dementia?
Based on symptoms
Levodopa (dopamine analogue)
Why do you not give dopamine antagonists (antipsychotics) for Lewy body dementia?
Can cause neuroleptic malignant syndrome which is a psychiatric emergency
What are the signs/symptoms of neuroleptic malignant syndrome?
Fever
Encephalopathy
Elevated creatine phosphokinasse
Rigidity
What is fronto-temporal lobe dementia?
Frontal and temporal lobe atrophy
What are the signs and symtpoms of fro to-temporal lobe dementia?
Behavioural disinhibition
Innappropriate social behaviour
Loss of motvaiotn without depression
Non fluent Broca’s aphasia
This are all mainly due to frontal lobe atrophy
What is thought to be the pathophysiology of fro to-temporal lobe dementia?
Aggregated proteins and Tau protein hyper-phosphoryaltion
What happens as a result to damage to the frontal lobe and then temporal lobe in front-temporal dementia?
Frontal:
-behavioural and emotional changes
-disinhibition
Temporal:
-language impairment
What is seen on MRI with fro to-temporal dementia?
Frontal/temporal atrophy
Ventricualr enlagremnt
What is vascular dementia?
Where cognitive impairment is caused by cerbrovascular disease (multiple mini strokes)
What are the risk factors for vascular dementia?
Any risk factors increasing risk of CVD:
Previous stroke MI
Hypertension
AFIB
Hypercholesterolaemia
Diabtes
Smoking
How does vascular dementia present?
Depends on area of brain affected
How does Vascualr dementia present on CT head?
Paler areas of infarcted cerebal tissue
How is vascular dementia treated?
Treat the risk factors (AIFB hypertension)
What is the pathology of AIDS/HIV dementia?
HIV infected macrophages cross the blood brain I barrier leading to damage oof neurones
Its the viral proteins damaging the brain not any opportunistic infections
What symptoms can AIDs dementia cause?
Behaviour
Memory
Thinking (psychomotor retardation)
Movement (cerebellar involvement)
Ataxia
Dysarthria
Incontinence
Why is HIV/AIDs dementia increasing?
People with HIV and AIDs are living longer so more cases are being seen
How is AIDs dementia managed?
Bio-psycho-social model
Bio:
Acetylcholinesterase inhbitors (donepezil)
NMDA antagonists (memantine)
Social
Explain diagnosis sensitively
Driving
What is delirium?
An acute confusional state which is an acute fluctuating syndrome of disturbed consciousness attention and perception
What are the features of deliurm?
Rapid onset confusion
Clouded consciousness
Fluctuating course
Transient visual hallucinations
Often exaggeretaed emotional responses
What are the 2 types of delirium?
Hypoactive
Hyperactive
What are some features of hypoactive delirum?
Withdrawn
Quiet
Sleepy
What are some features of hyperactive delirium?
Restless
Agitated
Aggressive
What arer some causes of delirium?
Drugs
Epilepsy /electolyte imbalance
Liver failure /low oxygen
Infection
Retention(urine/faecal)
Intracranial
Uraemia
Metbolism
What is the treatment of delirium?
Minimise/treat precipitating factors
Encourage normal day and night cycle
Allow wandering if safe
Medication is last resort (Haloperidol)
Go to slide 29 and label delirium vs dementia
