Dementias Flashcards
(28 cards)
A 74-year-old woman is more forgetful since a subdural haemorrhage. She loses items, gets disoriented, and struggles with daily tasks. Her MMSE is 21/30. What is the likely diagnosis?
Likely dementia; possibly Alzheimer’s disease or mixed dementia, but reversible causes must be ruled out.
What would a GP do to rule out reversible causes of dementia?
Take a full history, perform a mental state and physical exam, order blood tests (e.g., B12, TFTs), and arrange a CT/MRI scan.
How would a memory clinic diagnose the type of dementia?
Through clinical history, collateral history, cognitive testing, and neuroimaging.
What is cognition?
Mental processes of acquiring knowledge and understanding through thought, experience, and the senses.
What brain structure is primarily responsible for memory formation?
The hippocampus and para-hippocampal cortex.
What types of memory are involved in dementia?
Episodic (long-term recent memory), short-term (working memory), and semantic memory.
What is the role of the reticular activating system in cognition?
Maintains arousal and consciousness; contributes to attention and learning.
What neurotransmitter is crucial for memory and is deficient in Alzheimer’s?
Acetylcholine.
What structures produce acetylcholine for the cortex?
Basal forebrain nuclei and dorsolateral pontine nuclei.
According to ICD-11, what characterizes dementia?
Marked impairment in ≥2 cognitive domains affecting independence, due to an underlying brain disorder or systemic cause.
Can cognitive impairment in dementia be explained by normal aging?
No, it must be greater than expected for age and affect daily functioning.
What are the most common types of dementia and their approximate prevalence?
Alzheimer’s Disease: 62%
Vascular Dementia: 17%
Lewy Body Dementia: 4%
Frontotemporal Dementia: 2%
Mixed Dementia: 10%
What proportion of people over 80 have dementia?
1 in 6.
What pathology is seen in Alzheimer’s Disease?
β-amyloid plaques and hyperphosphorylated tau tangles, primarily in the mesial temporal lobes.
What are the early clinical features of Alzheimer’s?
Episodic memory loss, repeating questions, and misplacing objects.
Which neurotransmitter pathway is disrupted in Alzheimer’s?
Acetylcholine.
What causes vascular dementia?
Damage from reduced blood flow due to strokes or small vessel disease.
What are two phenotypes of vascular dementia?
Multi-infarct dementia – stepwise decline
Small vessel disease – slow decline with gait, urinary, and executive dysfunction
What are the core clinical features of Lewy Body Dementia?
Fluctuating cognition
Visual hallucinations
Parkinsonism
REM sleep behaviour disorde
What protein accumulates in Lewy Body Dementia?
Alpha-synuclein.
What are the behavioural features of frontotemporal dementia?
Disinhibition, apathy, loss of empathy, repetitive behaviours, hyperorality, and poor executive function.
What are the two language variants of FTD?
Progressive non-fluent aphasia
Semantic dementia
Name four rare causes of dementia.
Huntington’s disease, Creutzfeldt-Jakob disease, HIV-associated dementia, Parkinson’s disease.
Name five reversible or treatable conditions that mimic dementia.
Delirium
Depression
Drug side effects
Hypothyroidism, B12/folate deficiency
Subdural haemorrhage, Normal Pressure Hydrocephalus
