Pick’s Disease vs Lewy Body Dementia: Key Differences for Families

A note on the names

Pick's disease is not a precise modern diagnosis. It is commonly used to refer to frontotemporal dementia, or to a particular form of it. FTD is an umbrella term for conditions that mainly damage the frontal and temporal lobes, often affecting behaviour, personality or language first.

Lewy body dementia includes dementia with Lewy bodies and Parkinson's disease dementia. The two conditions have different typical early patterns.

How the early patterns often differ

There is overlap, and only a clinical assessment can establish the diagnosis.

Feature	Pick's disease / FTD	Lewy body dementia
Early changes	Personality, behaviour, judgement or language may change before significant memory loss	Attention, visual perception, alertness, movement, sleep or hallucinations may be more prominent
Empathy and social behaviour	Loss of empathy, tact, inhibition or motivation can be early features	Vivid hallucinations and fluctuations are more characteristic clues
Language	Trouble finding words, understanding words or producing speech can be an early leading symptom	Language can be affected, but it is usually not the main early feature
Movement	Usually less prominent early	Slowness, stiffness, shuffling, tremor, falls or fainting can occur
Hallucinations and sleep	Can occur, especially later, but are not the classic early pattern	Vivid visual hallucinations, fluctuating alertness and acting out dreams are recognised features

What about memory loss?

A person with FTD may initially remember recent events reasonably well but show striking changes in behaviour or language. In Lewy body dementia, significant memory loss may also be less obvious early on; attention, planning and visual-perception problems can come first.

Describe the full pattern rather than only saying ‘memory loss’. Specific examples of sleep, hallucinations, walking, eating, language, empathy, safety and changing alertness help a specialist identify the right questions and tests.

Why can diagnoses be difficult?

Dementia symptoms overlap, symptoms vary from person to person and more than one disease process can be present. Alzheimer's disease and vascular changes can coexist, and Lewy body disease can also occur alongside Alzheimer's changes. FTD can be mistaken for depression, relationship difficulty or a mental-health condition before its pattern is recognised.

Use the comparison to prepare for a GP or memory-service appointment, not to label a relative.

What to take to an assessment

A timeline from someone who knows the person well is particularly useful.

When behaviour, language or thinking first changed
Examples of loss of empathy, disinhibition, apathy or changes in food habits
Any vivid hallucinations, dream enactment, daytime drowsiness or sudden changes in alertness
Falls, tremor, stiffness, shuffling, fainting or swallowing changes
An up-to-date list of prescribed and over-the-counter medicines

The bottom line

Pick's disease is generally an older term connected with frontotemporal dementia, where personality, behaviour or language changes may lead. Lewy body dementia more often brings a combination of fluctuating attention, visual hallucinations, sleep changes and Parkinson's-type movement symptoms.

The differences can guide better questions, but diagnosis requires a clinician who can consider the whole pattern and rule out other causes.

Sources and further reading

Reviewed against trusted UK health guidance. Personal circumstances vary; speak to a qualified professional for individual advice.