Transcript Dementia syndrome Alzheimer disease

Dementia syndrome
Definitions
• The disturbance and symptoms significantly interfere with
work or usual social activities or relationships with others
• The syndrome associated with a progressive loss of
memory and other intellectual functions that is serious
enough to interfere with performing the tasks of daily life
•
The decline in intellectual function, including difficulties
with language, simple calculations, planning and
judgment, and motor (muscular movement) skills as well
as loss of memory
Signs and symptoms
• loss of cognitive ability
– memory
– attention
– language
– problem solving
• disorientation in time, in place, in persons
• behavioural problems
• emotional changes
• depression, anxiety, paranoia
Causes
• neurodegenerative diseases
– Alzheimer´s disease
– Parkinson´s disease
• stroke
• trauma
• chronic alcohol abuse
– Korsakoff´s syndrome
• genetic diseases
– Huntington disease
• metabolic diseases
– Tay-Sachs disease
– Gaucher disease
• infections
– Creutzfedt-Jakob disease
– viral encephalitis
The most frequent:
• Alzheimer´s disease 50-60%
• Vascular dementia
• Dementia with Lewy bodies
• Frontotemporal dementia
80%
90%
Alzheimer´s disease
History
1901 - German psychiatrist Alois
Alzheimer identified the first case of
what became known as Alzheimer's
disease in a 50-year-old woman he
called Auguste D (A. Deter).
Alzheimer followed her until she died in
1906, when he first reported the case
publicly.
Alois Alzheimer
Auguste D
Characteristics
4 stages
• Pre-dementia
– mild cognitive difficulties
– memory loss - remembering recently learned facts and inability
to acquire new information
– subtle problems with attentiveness, planning, flexibility, abstract
thinking
• Early dementia
– the increasing impairment of learning and memory
– difficulties with language - shrinking vocabulary and decreased
word fluency
– executive functions, perception (agnosia), or execution of
movements (apraxia)
• Moderate dementia
– inability to perform most common activities of daily living
– speech difficulties become evident due to an inability to recall
vocabulary, which leads to frequent incorrect word substitutions
– reading and writing skills are also progressively lost
– complex motor sequences become less coordinated - risk of
falling increases
– memory problems worsen – problems to recognise close
relatives
– behavioural changes – irritability, lability, aggression
– urinary incontinence
• Advanced dementia
– completely dependent upon caregivers
– language is reduced to simple phrases or even single words, or
complete loss of speech
– extreme apathy and exhaustion
– not be able to perform even the most simple tasks without
assistance
– immobility, they lose the ability to feed themselves
– death (infection, pneumonia)
Risk factors
Higher risk od AD
• age
 65 – 75 y
3%
 75 – 85 y
19%
 > 85 y
 50%
• positive family history
•
•
•
•
low degree of education
depression
women > men
trauma of head
Lower risk of AD ??
• antioxidants (ginkgo biloba) ?
• estrogens ??
• ibuprofen ??
• smoking ?????
Macroscopic changes
• brain atrophy – temporal lobe, parietal lobe, frontal cortex,
cingulate gyrus
• enlargement of ventricles
Microscopic changes
• loss of neurons and synapses in the cerebral cortex
• amyloid plaques
• neurofibrillary tangles
Amyloid plaques (senile plaques)
• dense, mostly insoluble deposits of beta-amyloid peptide
outside and around neurons
• beta-amyloid - small peptide (39–43 amino acids)
• a fragment from the amyloid precursor protein (APP) – a
transmembrane protein of neurons
• APP is critical to neuron growth, survival and post-injury
repair
• in Alzheimer's disease, an unknown process (mutation of
APP gene?) causes APP to be divided into smaller
fragments by enzymes (proteolysis)
• accumulation of aggregated amyloid fibrils – toxic disrupting the cell's calcium ion homeostasis, induces
apoptosis (hypothesis)
Neurofibrillary tangles
• aggregates of fibres
• hyperfosforylated protein tau - accumulate inside the
cells
• normal function of tau protein - stabilizes the
microtubules (important for transport in neurons) –
microtubule-associated protein
• in AD - tau is hyperphosphorylated – composes pairs
with other threads, creating neurofibrillary tangles and
disintegrate the neuron's transport system
Other factors
• Presenilins 1 and 2 – transmembrane proteins
– mutations in Alzheimer disease
• Allele e4 of apolipoprotein E
– 3 alleles – e2, e3, ee4
– e4 – higher risk of atherosclerosis and Alheimer
disease
The mini-mental state examination (MMSE) or Folstein test - brief 30-point
questionnaire test - used to screen for cognitive impairment.
Category
Possible
Description
points
Orientation to
time
5
From broadest to most narrow. Orientation to time
has been correlated with future decline.
Orientation to
place
5
From broadest to most narrow. This is sometimes
narrowed down to streets,[and sometimes to floor.[
Registration
3
Repeating named prompts
Attention and
calculation
5
Serial sevens, or spelling "world" backwards. It has
been suggested that serial sevens may be more
appropriate in a population where English is not the
first language.
Recall
3
Registration recall
Language
2
Name a pencil and a watch
Repetition
1
Speaking back a phrase
Complex
commands
6
Varies. Can involve drawing figure shown.