Dementia Flashcards
what is dementia?
a fatal neurodegenerative disorder that is characterized by progressive cognitive, social and functional impairment
what is the most common cause of dementia?
alzheimers disease
What is the cure for dementia?
There is no current cure, with acetylcholinesterase inhibitors having
modest symptomatic benefit in early stages
what are the four most common causes of dementia?
Alzheimer’s disease, vascular dementia, frontotemporal dementia, dementia with Lewy bodies
List some of the potentially reversible causes of dementia
depression, alcohol related brain damage, endocrine causes, B1/B12/B6 deficiency, infection, inflammation
How does cognitive function decline due to dementia in comparison with normal aging?
general decrease with age. With dementia: preclinical deterioration in cellular function until clinical manifestation with mild cognitive impairment leading to dementia
why is dementia hard to diagnose?
The disease follows a heterogenous
course
* In old age the disease presentation is of
multiple co-morbidities
* Lots of mixed and uncertain pictures
* Younger patients are more typical
* Clinical history, the function of the patient
and how they change is paramount
what are the two most important molecules in the pathology of dementia?
amyloid, tau
when interviewing a suspected dementia patient what are the most important things to check?
memory, language, numerical skills, executive skills, personality, sexual behaviour, mood, delusions and hallucinations along with the chronology of each
outline the general process for diagnosis of dementia?
referral, history, examination, investigation, diagnosis, management
what do dementia examinations include?
neurological mental state, focus tests, limb functions, appearance, behaviour, insight and speech
what investigations are done when diagnosing dementia?
Neuropsychology, bloods, MRI, PET
list three cognitive tests that may be undertaken in the diagnosis of dementia
MMSE, Addenbrookes, Montreal cognitive assessment
What are the management options for dementia?
Acetylcholinesterase inhibitors
Watch and wait
Treating behavioural/psychological
symptoms
OT/Social services
Specialist therapies
what are the three most important considerations for cognitive impairment?
Delirium, dementia, depression
How does the progression of Alzheimer’s show on an MRI?
gyri narrow, sulci widen, ventricles become more dilated, loss of medio temporal volume and hippocampal volume
How does Alzheimer’s present?
subtle, insidious onset with amnestic presentation. symptoms of anomia, agnosia, aphasia.
what is anomia?
inability to name objects
How does vascular dementia present?
Classical step-wise deterioration, associated with cerebrovascular diseases. symptoms include slower thinking, personality changes, movement problems and bladder problems
What are Lewy bodies
aberrant deposits of alpha-synuclein protein in the brain.
How does dementia with Lewy bodies present?
cognitive impairment with 1 year of parkinsonian symptoms, visual hallucinations and fluctuating cognition. progressive and insidious onset over time
How does frontotemporal dementia present?
speech problems, behavioral changes, emotional problems and disinhibition. can cause semantic dementia, progressive non-fluent aphasia
What causes the neuronal atrophy of the frontal and temporal lobes associated with frontotemporal dementia (FTD)?
presence of abnormal proteins, predominately phosphorylated tau
what are the distinct biomarker patterns associated with Alzheimers?
amyloid is the primary event, followed by tau, then changes to brain structure that affect cognition
How is CSF used in Alzheimers diagnosis?
CSF taken via a lumbar puncture. beta-amyloid is lower in someone with Alzheimer’s. CSF tau is higher
How does dementia with Lewy bodies appear on an MRI?
preserved hippocampal volume and medial temporal lobe volume on a DaTscan
what is a DaTscan?
dopamine transporter level scan
outline the role of amyloid plaques in the pathophysiology of Alzheimer’s disease
insoluble beta-amyloid peptide deposits as senile plaques or beta-pleated sheets in the hippocampus, amyglada and cerebral cortex. increased density in advanced disease
outline the role of neurofibrillary tangles (NFTs) in the pathophysiology of alzheimers disease
consist of phosphorylated tau protein and are found in the cortex, hippocampus,and substantia nigra (NFTs are also found in normal aging)
alzheimers can result in a loss of up to ___% of neurons and synapses in __________
50% loss in the cortex and hippocampus
what four genes are implicated in Alzheimers disease?
chromosome 21
chromosome 19
chromosome 14
chromosome 1
why is chromosome 21 implicated in alzheimers disease?
the gene for amyloid precursor protein (APP) is found in the long arm
why is chromosome 19 implicated in Alzheimers disease?
codes for apolipoprotein E4,presence of these alleles increases risk of AD
why is chromosome14 implicated in Alzheimers disease?
codes for presenilin 1 (implicated in B-amyloid peptide)
what does the cholinergic hypothesis suggest?
suggests that dysfunction of ACh containing neurons in the brain contributes substantially to the cognitive decline seen in old age and AD
per the cholinergic hypothesis, dysfunction of ACh containing neurones leads to pathological changes that result in what?
degeneration of cholinergic nuclei in the basal forebrain (nucleus basalis of Meynert)
tha pathological changes that lead to degeneration of cholinergic nuclei in the basal forebrain results in what?
reduced cortical acetylcholine
what two types of drugs form the primary bases of pharmalogical treatment of AD?
acetylcholinesterase inhibitors and NMDA receptor antagonists
what does the term confabulation mean?
fabrication of events to fill in gaps in memory
can add credence to paranoid beliefs and exacerbates psychotic phenomena like psychosis
what behavioural disturbances can AD patients present with?
aggression
wandering
explosive temper
sexual disinhibition
incontinence
excessive eating
searching behaviour
