Dementia Flashcards
What are the 4 main causes of late-onset dementia, and rank them from the most prevalent to the least?
Alzheimer’s,
Vascular,
Dementia with Lewy Bodies,
Frontotemporal
What is the cut-off for young onset dementia and how does the prevalence of causes change?
- under 65
Frontotemporal more prevalent than Lewy Bodies
‘Other’ causes are more common as well
What are some potentially reversible causes of dementia?
Depression,
Alcohol related brain Damage,
Endocrine disorders,
HIV/Syphilis,
Inflammation
What are rarer irreversible causes of dementia?
MS, Huntigton’s
Why is dementia difficult to diagnose in clinic?
Heterogenous course,
most patients are older with multiple co-morbidities
clinical history and function of patient is important for diagnosis
Neuro-inflammatory risk factors of dementia
Ageing
brain trauma
infections/ systemic inflammation
oral health
reduced physical activity
genetic factors
midlife obesity
What are some of the pathological proteins that may be present in dementia?
Alpha-synuclein, Neuronal tau, Amyloid angiopathy
What is the pathway for clinical diagnosis in dementia?
Referral, History, Examination, Investigation, Diagnosis, Management
What are the 10 components of the clinical interview?
Memory, Language, Numeracy, Visuospatial, Personality, Sexual Behaviour, Eating, Delusions/Hallucinations, Route Finding, Daily Life
How does the cognitive presentation of dementia vary with the cause?
Severe loss of memory and cognitive abilities REGARDLESS of underlying cause
What are the components of examination of dementia?
Neurological Mental State Exam -> cranial, spinal nerve testng, focus tests, speech test, thought form, insight
What are some of the **investigations **that you would do for dementia?
Neuropsychology tests, Bloods, MRI, PET
What is the MMSE?
Mini-Mental State Examination
Examination for orientation, attention, recall, language
What are two common tests for neuropsychology?
Mini-Mental State Examination (MMSE), Addenbrooks Cognitive Assessment
What are the blood tests you would do for dementia?
FBC, Inflammatory Markers, Renal Function, Liver (Caeruloplasmin - copper carrier), Glucose, B12 & Folate, Syphilis and HIV
Structural MRI (sMRI) Alzheimer’s presentation
As disease progresses, AD brain has narrow gyri, widened sulci, ventricles dilated and enlarged, medial temporal volume loss, bilateral hippocampal volume loss. space replaced with CSF showing up as black
How can you do PET Scans post-mortem to assess the likelihood of Alzheimer’s?
Inject fluoride, will be taken up by beta-amyloid protein. Uptake of 1.5% and upwards is a high likelihood of Alzheimer’s
how are Amyloid PET scans used for diagnosis
areas of the brain containing amyloid light up as they take up the fluorescent marker
What are some of the differentials with diagnosing dementia?
4 types of dementia, depression, delirium, or nothing at all
What is the main symptomatic medication given for dementia?
Acetylcholinesterase inhibitors, only effective at early stage (MMSE = 1)
Why does diagnosis of dementia take a long time?
Clinical process has reiterations to rule out delirium, depression etc. Will take 6 months - 1 year
How does Alzheimer’s present?
Subtle, insidious episodic amnesia
How does Vascular dementia present?
Stepwise deterioration, associated with strokes
related to cerebrovascular disease
How does dementia with Lewy Bodies present?
Fluctuating cognition,
visual hallucinations,
develops into Parkinsonian symptoms
REM sleep disorder
high risk of falls
How does Frontotemporal dementia present?
Progressive non-fluent aphasia, anomia, personality changes, semantic dementia
What is a sign you can see in Alzheimer’s patients?
Head turning signs - as they look to others for verification after question is asked
(makes a lot of mistakes especially with meds)
Episodic memory
- particular episodes in life
- dependent on Medial temporal lobes - hippocampus and entorhinal cortex
How does the evolution of amyloid deposition in the brain occur in Alzheimer’s?
Starts in outer cerebral cortex, increases severely, then travels to other brain structures and down brainstem
How does the evolution of tau in the brain occur in Alzheimer’s?
Starts in lower temporal lobe, spreads to anterior frontal lobe, then to occipital, then moves up to the top of the brain
How can you use CSF to diagnose Alzheimer’s?
CSF from a lumbar puncture, amyloid will be lower than normal and tau will be higher than normal
How do Lewy Bodies form in the brain?
Alpha-synuclein monomers bind together and strengthened with neurofilaments, form lewy bodies
What will you see on a patient with dementia with Lewy Bodies, compared to Alzheimer’s?
Decreased uptake by dopamine receptors
preserved hippocampal volume, general medial temporal low volume
How can you image dementia with Lewy Bodies without MRI?
SPECT (single proton emission computerised tomography) imaging - inject iodine and see uptake
relationship between lewy bodies and dopamine
Lewy bodies build and prevent the uptake and transmission of dopamine
FTD MRI presentation
Perisylvian volume loss, space at the side of the head
characteristic with behavioural disturbance
What is anomia?
Inability to name objects
