Week 6: Dementia Flashcards
Is dementia a specific disease?
No, it is not a specific disease but rather an overall term that describes a wide range of symptoms associated with declines in memory or other cognitive skills that reduce everyday abilities
What are progressive dementias?
They are characterised by a continual decline in functioning overtime
What categories of dementia are considered to be progressive?
Cortical dementias
Subcortical dementias
Mixed dementias
Examples of cortical dementias?
AD
Picks disease
Frontal lobe dementia
Examples of subcortical dementias?
Huntingtons disease
Parkinsons disease
Examples of mixed dementias?
Lewy body dementia
Multi-infarct (vascular) dementia
What are potentially static dementias?
These dementias are not progressive
What categories of dementia are considered to be potentially static?
Toxic conditions - heavy metal poisoning
Infectious conditions - herpes encephalitis
Miscellaneous - tumour, trauma
What are some potentially reversible dementias?
Systematic illnesses - amnesia
Deficiency states - vit b12
Endocrine disorder - addisons disease, thyroid disorders
Drug toxicity - antipsychotics
What is an example of psuedodementia?
Depression
What is the most prevalent dementia?
Alzheimers disease
Who diagnoses dementia?
Geriatrician, neurologist or medical practitioner
Whos opinion is essential for dementia diagnosis?
Clinical neuropsychologists
Why is early diagnosis important for every case?
Provided with a diagnostic answer and possible education for the patient and family to relieve fear
Why is early diagnosis important for static dementia?
You can then treat the underlying disease and initiate prevention and rehabilitation strategies
Relieve the patients fear of an irreversible disease
Why is early diagnosis important for progressive dementia?
You can begin to treat behavioural and cognitive symptoms (eg. memory strategies)
Can also make legal and financial plans while the patient is still competent
What is dementia labelled in the DSM-5?
Neurocognitive disorder (NCD)
- much broader classification
Diagnostic criteria for NCD?
Evidence of significant cognitive decline from a previous level of performance
- Has to be notable by others
- Need testing to assess
Deficits interfere with independence in everyday life
The deficits do not occur exclusively in the context of a delirium
The deficits are not better explained by another mental disorder
When diagnosing someone with MND, you need to…
- Specify what type/cause
- Specify the extent of behavioral disturbances
- specify severity
Cortical to subcortical dementia?
Cortical dementia is characterized by preferential neuronal loss to the cortical regions of the brain
This can progress and start to affect subcortical regions of the brain (later stages of the disease)
Why is there a lot more deficits in movement with subcortical dementia?
Involves areas important for movement such as the basal ganglia
E.g. Parkinsons dementia is dementia of the subcortical type
What is the strongest predictor for AD?
Age - incidence increases with age
Are there any gender differences in AD?
Twice as many women as men
What is the average duration of AD?
8-10 years
Those with AD rarely survive more than 15 years post-diagnosis
Why may AD symptoms not be noticed until later on?
May not know because the brain is so good at using cognitive reserves to compensate for loses - however it gets to a point where you just can’t compensate anymore
Sporadic vs. familial AD?
Sporadic: most common type, not a strong genetic basis (APOE34 gene) - typical onset after 80 years
Familial: rare - but strong genetic trait
Early onset dementia - after 50 years
Where does cell loss occur in AD?
Cortical grey matter of the brain and limbic structures (hippocampus, amygdala)
Which lobes are the most atrophied in AD?
Frontal, temporal and parietal
How many cells are lost in affected lobes (AD)? and why?
Estimated 50% of large neurons in these areas
Due to a loss of dendritic arborisation (decreases and declines in dendritic branching that allows the brain to form connections)