Registered Nurses' Association of Ontario

Nursing Best Practice Guidelines

What are the types of Dementia?

Types of Dementia 


Disease 
Dementia of Alzheimer Type (DAT)

Onset
Insidious (1-2 years before diagnosis and treatment sought)

Progression
Gradual and continuous over years

Course
Usually 8-10 years but variable (3-20 years)

Characteristics

  1. Short term memory affected first, loss of executive functions (IADL first)
  2. Orientation to time lost second
  3. Orientation to place lost third
  4. In later stages, loss of motor and sensory functions (hallucinations, delusions, apraxias, falls)

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Disease 
Vascular Dementia (VD)

Onset
Sudden

Progression
Step-like

Course
Variable

Characteristics

  1. Presence of vascular risk factors (hypertension, hypercholesterolemia, diabetes, smoking, TIAs, atrial fibrillation or evidence of previous stroke)
  2. Presentation varies according to area(s) of brain affected. May get focal deficits, gait problems, early incontinence, physical deficits
  3. More likely to display agitation
  4. Delusions & hallucinations less common

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Disease 
Frontotemporal Dementia (FTD)

Onset
Slow

Progression
More rapid than DAT

Course
2-7 years

Characteristics

  1. Bizzare behaviours, incongruous with previous personality
  2. More common in males
  3. Age of onset earlier, before cognitive decline evident
  4. Subsets with aphasia, apraxia & agnosia have frontal Pick's Bodies
  5. Apathy
  6. Behaviours usually socially inappropriate (explosive anger/agitation with loss of self awareness & growing disinhibition, grooming & hygiene problems)

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Disease 
Dementia of Lewy Body Type (LBD)

Onset
Slow

Progression
Rapid, fluctuating but progressive

Course
+/- 5 years

Characteristics

    • First fluctuating confusion Onset of hallucinations but cognition intact (except for SMMSE diagram or Clock)
    • Parkinsonism leading to increasing falls, gait disorder
    • Increased rigidity, decreased mobility Hypersensitive to neuroleptics (Hallucinations rarely eliminated while rigidity and tardive dyskinesia occurs)

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