Dementia Flashcards
1
Q
Definition of Dementia
A
- category of degenerative brain diseases:
- deteriorate cognition/affect/behavioural functions
- severe enough to impede daily functioning
- represent a decline from previous function
- worse than expected from normal aging
2
Q
Major Neurocognitive Disorder
A
- DSM5, psych equivalent of dementia
- significant cognitive decline in one or more domains, based on concerns and impairment on testing
- interferes with independence and social functioning
- not exclusively in the context of delirium
- not better explained by another disorder
3
Q
What are the six cognitive domains?
- how to test
- areas of brain
A
- Complex attention –> focus on task despite distraction, working memory, processing speed
- test with serial 7s
- mainly frontal lobes, also parietal - Executive Functioning –> planning, correcting, inhibition, mental flexibility, goal-oriented tasks
- test by copying shapes
- mainly frontal lobes - Learning and Memory –> visual and verbal memory, semantic and episodic memory, short and longterm
- test with recall and recounting events
- mainly temporal lobes - Language –> motor (syntax, fluency, word-finding, writing) is dominant frontal lobe
–> sensory (comprehension, reading) is dominant temporal and parietal lobes
- test with yes/no questions, commands, complex syntax - Perceptual-Motor –> gnosis (recognizing), copying drawings is occipital-temporal lobes
–> praxis (gestures, using tools), construction is frontal-parietal lobes
- test with clock drawing - Social Cognition –> appropriate behaviour, consistent decisions, understanding emotions
- frontal lobes
4
Q
Gold standard for assessing dementia?
A
- Neuropsychological assessment, but this is often difficult to access so MMSE, MoCA
- Substantial impairment is considered at least 2SD below average
5
Q
MMSE
A
- widely used and understood
- not well balanced (no executive functioning, tests lower end of functioning)
- really only for alzheimer’s
6
Q
ADLs vs IADLs
A
ADLs –> Dressing, Eating, Ambulating, Toileting, Hygiene (DEATH)
IADLs –> Shopping, Housekeeping, Accounting, Food Prep, Transport/Telephone, Medications (SHAFT-M)
7
Q
How to determine functional impairment?
A
- collateral information
- questionnaires (disability assessment for dementia)
- make house calls, OT/nursing
8
Q
Mild Neurocognitive Disorder (mild cognitive impairment)
A
- symptoms of dementia are present but no functional impairment
- often precursor of major neurocognitive disorder
9
Q
Delirium
A
- usually an underlying cause
- symptoms develop and fluctuate rapidly
10
Q
Alzheimer’s
A
- meets dementia criteria AND:
- insidious (gradual onset)
- clear cut history of worsening condition
- initial and most prominent deficits are amnesia, impaired learning and recall
- evidence of dysfunction in at least one other domain
- can be atypical (language, visuospatial, executive)
- most common cause of dementia in older adults
- rare before 50
11
Q
Physical Changes Seen in Alzheimer’s
A
- neuritic senile amyloid plaques (amyloid beta specific to AD, deposits of fibrillar protein aggregates), central amyloid core surrounded by dystrophic neurites, affects neocortex the most
- neurofibrillary tangles (hyperphosphorylated tau protein) - can be seen in other diseases
- neuropil threads
- mesial temporal lobes (memory) have greatest tangle pathology (hippocampus)
- cortical atrophy most pronounced in frontal/temporal/ parietal on MRI
- medial temporal lobe and limbic system affected early and severely (memory)
- nucleus basalis of Meynert affected –> main cholinergic nucleus in the CNS, thought to modulate attention/learning/longterm memory
- relative preservation of grey matter and the brainstem (motor issues are rare)
- amyloid beta can also deposit in leptomeningeal and superficial cortical vessels (not specific to AD, can cause hemorrhages in elderly)
12
Q
Vascular Dementia
A
- clinical and imaging features suggest vascular contribution –> onset of deficits correlate with cerebrovascular events and/or a decline in complex attention and executive function
- rare by itself
- i.e. frontal subcortical dementia (frontal lobe and basal ganglia infarcts)
13
Q
What are dementias associated with Parkinson’s? What are typical symptoms?
A
- Lewy Body dementia, PD dementia, other rare syndromes
- extrapyramidal symptoms –> tremor, bradykinesia, rigidity, gait shuffle/ stoop, postural instability
14
Q
Lewy Body Dementia
- including physical brain changes
A
- 2 of:
- one or more features of PD
- visual hallucinations
- REM sleep behaviour disorder
- fluctuating cognition with variation in attention and alertness
- Supportive: falls, ANS dysfunction, hypersomnia, anosmia, delusions, sensitivity to antipsychotics, apathy
- substantia nigra degeneration
- classical LBs (brainstem) and cortical LBs, lewy neurites
- variable atrophy
15
Q
PD Dementia
A
- most patients with PD eventually develop dementia
- basically identical to Lewy Body dementia, but the PD motor symptoms start at least 1 year before the onset of cognitive impairment
- some have more frontal-subcortical symptoms (complex attention, processing speed, executive functioning) –> less hallucinations and no fluctuations
16
Q
Behavioural Variant Frontotemporal Dementia
A
- dysfunction of salience network –> social cognitive function
- atrophy of frontal lobe seen on imaging
- mostly TDP-43 and tau
- progressive decline in behaviour/cognition and at least 3 of:
- behavioural disinhibition
- apathy or inertia
- loss of sympathy/ empathy
- perseverative, stereotyped, compulsive, ritualistic behaviour
- hyperorality, dietary changes
- decline in executive function with relative sparing of memory and visuospatial functions
17
Q
Primary Progressive Aphasia (Frontotemporal Dementia)
- 3 subtypes
A
- dysfunction of language networks
- atrophy of frontal and temporal regions on MRI
- mostly TDP-43 and tau
- all 3 of:
- most prominent decline is language
- deficits are main cause of decline in ADLs
- aphasia is most prominent early on
- cannot have ANY of:
- prominent initial memory/ visuospatial/behavioural disturbances
- agrammatic/nonfluent –> halting, errors, effortful, inconsistent
- semantic –> no comprehension of single words, trouble naming objects
- logopenic –> word-finding, repetition (often a language variant of alzheimer’s)
18
Q
Neurodegenerative Disease
A
- slowly progressive dementia
- unknown cause, can be sporadic or inherited
- atrophy, neuron loss, gliosis, microglial activation, degeneration of white matter tracts, protein deposits, cellular inclusions
- classified by the type of abnormal protein
19
Q
Amyloid beta Hypothesis of AD
A
- is the primary cause of dementia accumulation of abeta or tau?
- some tau pathologies without ab don’t lead to AD
- ab needed for tangles to spread to the cortex
- ApoE4 increases ab
- ab is neurotoxic, cause inflammation from microglia and astrocytes
20
Q
ApoE
A
- ApoE on Ch.19 increases risk of AD
- E4 specifically increases risk and lowers age of onset
- increases abeta but also exacerbates tau neurodegeneration
21
Q
Specific Tests for AD
A
- decreased AB42/AB40 in CSF
- increased tau/p-tau in CSF
- increased p-tau181 in plasma
22
Q
Treatments for AD
A
- cholinesterase inhibitors
23
Q
Most common dementia presentation?
A
- AD + vascular + other degenerative cause
24
Q
What is normal sleep?
A
- latency under 30m
- brief arousals under 10s
- brief awakenings under 30m total
- total time 6-8h (less with age)
- no daytime sleepiness
*sleep good for GH secretion, preventing infection, restoration via glymphatic system
25
Q
Sleep Stages
A
1 –> 5% total sleep time, light sleep, transitional, if too much it can lead to sleep disruption
2 –> 50% total sleep time, medium sleep
3 –> 15-20% total sleep time, deep sleep, hard to awaken and sleep inertia when done so, NREM parasomnias (sleep walking/talking/terrors/confusional arousals)
- most restorative
- impaired by benzos, maintained by zopiclone and zolpidem
REM –> dreams, tonic (voluntary muscle atonia) and phasic stages (REM, twitching of voluntary muscles)
*measured by a hypnogram
