Definition of dementia

an acquired persistent impairment of intellectual function with compromise in memory and at least two other cognitive domains such as language, visuospatial skills or executive function

Prevalence of dementia

0

5

10

15

20

Pre

vale

nce

Rat

e (%

)

1

85+

80-84

75-79

70-74

65-69

60-64

60-64 65-69 70-74 75-79 80-84 85+

AGE

Causes of dementia

• Neurodegenerative disorders

- Alzheimer’s disease- Pick’s disease

• Vascular (multi-infarct) dementia

• Reversible causes

Alzheimer’s disease

Vascular dementia

Other causes

Alzheimer’s disease

• cognitive deficits- profound memory loss

(anterograde/retrograde)

- language - anomic, empty, circumlocutory

- visuospatial disturbance

• behavioral deficits- no significant early changes in personality

- unawareness or denial of illness

- psychosis

• no sensory or motor deficits

Cortical atrophyNormal brain

Cortical atrophy

Cortical atrophy - MRI scan

Alzheimer’s disease

Normal

Alzheimer’s

Neurofibrillary tangles(tau protein)

Amyloid plaques

Pathology of Alzheimer’s disease

Degeneration of the basal forebrain cholinergic system

Pathology of Alzheimer’s disease

Treatment of Alzheimer’s disease

• Cholinergic replacement

• Anti-amyloid agents

Pick’s disease/frontal dementias

• cognitive deficits- profound executive dysfunction

- good memory, language, visuospatial skills

• behavioral deficits- early prominent personality changes

- poor judgment, insight, disinhibited, labile, euphoric, socially inappropriate, sexual indiscretions

• frontal release signs on neurological exam but no senory or motor deficits

Cortical atrophy

Cortical atrophy - MRI scan

Pick’s disease

PET scan of Pick’s disease

Pick’s bodies

Pathology of Pick’s disease

Alzheimer’s

Pick’s