Alzheimer and vascular dementia vs Lewy body and frontotemporal dementia
How to tell Alzheimer and vascular dementia and Lewy body and frontotemporal dementia apart when a board question makes them look alike.
Alzheimer is memory-first gradual; vascular is stepwise stroke-linked; Lewy is hallucination/fluctuation; frontotemporal is behavior/language-first.
Side by side
Alzheimer disease is gradual memory-first decline; vascular dementia is stepwise cognitive decline after strokes or vascular injury with focal neurologic signs or imaging infarcts.
Lewy body dementia has early hallucinations, fluctuations, REM sleep behavior disorder, and parkinsonism; frontotemporal dementia has early personality, disinhibition, apathy, compulsions, or language-predominant decline.
Alzheimer disease involves amyloid plaques and tau tangles affecting memory networks; vascular dementia reflects accumulated ischemic or hemorrhagic brain injury.
Lewy body dementia involves alpha-synuclein pathology; frontotemporal dementia involves frontal/temporal neurodegeneration with tau or TDP-43 pathology in many cases.
Progressive amnestic syndrome supports Alzheimer; stepwise decline with infarcts, gait or focal deficits supports vascular dementia.
Visual hallucinations/fluctuations support Lewy body dementia; early behavior or language syndrome with frontal/temporal atrophy supports frontotemporal dementia.
The trap
All four cause dementia, so the question is which cognitive domain failed first and how the course evolved. Alzheimer is gradual amnestic decline starting with short-term memory and hippocampal atrophy; vascular is stepwise decline with focal deficits and infarcts on MRI; Lewy body is early visual hallucinations and cognitive fluctuations with parkinsonism and REM sleep behavior disorder, plus severe neuroleptic sensitivity (avoid haloperidol); frontotemporal is early personality change or progressive aphasia in a younger patient (50s to 60s) with frontal/temporal atrophy, memory often preserved early. The Lewy body antipsychotic trap is high-yield: giving haloperidol to a Lewy body patient can precipitate severe parkinsonism and autonomic failure.
The repair move
For dementia, identify the earliest domain and whether the course is gradual, stepwise, fluctuating, or behavioral.
Try a free question
CoreAn older adult has gradual progressive episodic memory loss, impaired new learning, and later language and executive dysfunction. There are no early hallucinations, stepwise strokes, or marked early personality changes. Which diagnosis is most likely?
Show answer and explanation
Answer: A. Alzheimer disease. Gradual memory-first dementia supports Alzheimer disease because episodic memory and new learning are typically affected early.
Why the other choices are tempting
- B. Vascular dementia is stepwise and linked to strokes or infarcts.
- C. Lewy body dementia has early hallucinations, fluctuations, REM sleep behavior disorder, or parkinsonism.
- D. Frontotemporal dementia has early behavior or language changes.
- E. NPH has gait disturbance, urinary incontinence, and ventriculomegaly.
Flashcards
Tap a card to flip it.
What early cognitive pattern points to Alzheimer disease?
Gradual episodic memory loss and impaired new learning point to Alzheimer disease.
What tempo points to vascular dementia?
Stepwise decline after strokes or vascular events points to vascular dementia.
Quick answers
What is the fastest way to tell Alzheimer and vascular dementia from Lewy body and frontotemporal dementia?
Alzheimer is memory-first gradual; vascular is stepwise stroke-linked; Lewy is hallucination/fluctuation; frontotemporal is behavior/language-first.
What is the key clue for Alzheimer and vascular dementia?
Alzheimer disease is gradual memory-first decline; vascular dementia is stepwise cognitive decline after strokes or vascular injury with focal neurologic signs or imaging infarcts.
What is the key clue for Lewy body and frontotemporal dementia?
Lewy body dementia has early hallucinations, fluctuations, REM sleep behavior disorder, and parkinsonism; frontotemporal dementia has early personality, disinhibition, apathy, compulsions, or language-predominant decline.
What is the common trap with Alzheimer and vascular dementia vs Lewy body and frontotemporal dementia?
All four cause dementia, so the question is which cognitive domain failed first and how the course evolved. Alzheimer is gradual amnestic decline starting with short-term memory and hippocampal atrophy; vascular is stepwise decline with focal deficits and infarcts on MRI; Lewy body is early visual hallucinations and cognitive fluctuations with parkinsonism and REM sleep behavior disorder, plus severe neuroleptic sensitivity (avoid haloperidol); frontotemporal is early personality change or progressive aphasia in a younger patient (50s to 60s) with frontal/temporal atrophy, memory often preserved early. The Lewy body antipsychotic trap is high-yield: giving haloperidol to a Lewy body patient can precipitate severe parkinsonism and autonomic failure.