Alzheimer's (done) Flashcards
What is dementia?
Progressive, irreversible clinical syndrome w a range of cognitive & behavioural symptoms –> including:
- Memory loss
- Problems with reasoning & communication
- Changes in personality
- Reduction in the person’s ability to carry out daily activities
What are multiple cognitive deficits?
- Memory dysfunction is major early symptom - especially learning new info
- Diagnosis req deficits in at least 2 cognitive domains: memory, language, behaviour, visuospatial, or exec function
What are the 2 main criteria req to diagnose dementia?
- Multiple cognitive deficits
- Cognitive disturbances
What are cognitive disturbances?
- Sufficiently severe to cause impairment of occupations or social functioning (activities of daily living; ADL)
- Must represent a decline from previous level of functioning
- Cannot be explained by delirium or other major psychiatric disorder
List the 10 causes of cognitive deterioration:
1 - Alzheimer Disease (pure ~40% & mixed ~70%)
2 - Vascular disease, Multi-Infarct Dementia
3 - Drugs, Depression, Delirium
4 - Ethanol (5-15%)
5 - Medical/Metabolic systems
6 - Endocrine (thyroid, diabetes), Ears, Eyes Environment
7 - Neurologic (other primary degenerations)
8 - Tumor, Toxin, Trauma
9 - Infection, Idiopathic, Immunologic
10 - Amnesia, Autoimmune, Apnea, Age-Associated Memory Impairment
(Alzheimer’s is main cause)
What are the 6 requirements for an AZD diagnosis?
A - Multiple cog deficits (1. memory impairment, 2. other cog impairments)
B - Deficits impair social/occupational life
C - Course shows gradual onset & decline
D - Deficits not due to: 1. other drug use, 2. substance-induced conditions
E - Do not occur exclusively during delirium
F - Not due to another psychiatric disorder
(Autopsy needed of +ive diagnosis)
What two diseases have different underlying causes but their outcome is similar?
Alzheimer’s disease & vascular dementia
What are the 4 requirements for a Vascular dementia diagnosis?
A - Multiple cog deficits (1. memory impairment, 2. other cog impairments)
B - Deficits impair social/occupational life
C - Focal neurological signs & symptoms or lab evidence indicating cerebrovascular disease eitology related to the deficits
D - Not due to delirium
When was AZD first described & how was it defined?
First described in 1906 by Alois Alzheimer
Progressive deterioration of cognitive function without antecedent cause, such as stroke
What are the 2 types of onset that can happen in AZD & what are they called?
Familial = early onset
Sporadic = late onset
Why is it important to understand AZD more?
Growing problem w an ageing pop –> more than 2% of population are over 65
It costs £20bn/yr in the UK
What is the prevalence of AD?
11% in 65 year old –> but rising to 50% of those over 85
What is the life expectancy of AD?
5-8 years from diagnosis
How is it determined what stage of AD you are at?
An MMSE test must be taken
This is marked out of 30
(Ranked; early diagnosis, mild-moderate 20 or below & severe 5 or below)
What is the main diagnostic marker of AD?
beta-amyloid plaques
What are beta-amyloid plaques?
- Large neurotoxic aggregates of insoluble protein (42 amino acid peptide termed “beta amyloid”
- Initially only possible to detect via post-mortem diagnosis
Where are beta-amyloid plaques found?
Outside the cell:
They are extracellular deposits that form in neural tissue –> causing gliosis
What are the two neuropathological elements found in AD?
The two markers seen in the brain
- Beta-amyloid plaques
- Neurofibrillary tangles
What are neurofibrillary tangles?
Disorganised bundles of filaments in the neuronal cytoplasm
How are neurofibrillary tangles formed?
Formed by hyperphosphorylated tau proteins, causing aggregation & precipitation of the cytoskeleton
How was AD initially certainly diagnosed?
A certain diagnosis could only be done via post-mortem histochemistry –> needed to identify beta-amyloid plaques & NFTs
How can we now diagnose AD?
Imaging techniques such as PET & fMRI enable us to see beta-amyloid plaques & NFTs in vivo
What happens to the brain pathology in early AD?
Degeneration of the cells in the hippocampus (links to memory loss)
What happens to the brain pathology in mild to moderate AD?
Atrophy of the cerebral cortex, enlarged ventricles
- Decline in reading judgement & language, emotional outbursts
- Forget how to do simple tasks (e.g. brushing teeth)
- Cannot think clearly
Why do patients with mild to moderate AD begin to experience emotional outbursts?
The thinning of the gyrus occurs here - emotional effects begin when the amygdala is affected
The amygdala controls emotions
What is the brain pathology like in advanced to final AD?
- Death of more nerve cells
- Agitation, wandering
- Inability to recognise faces & communicate