Dementia Flashcards
what is dementia
- a set of symptoms that include memory loss and mood changes
- there are many types not just AD
- any cause of dementia will affect the brain
origins of dementia
- degenerative
- vascular
- infective
- toxic
AD
- physical disease - named after the doctor who first described it (Alois)
- proteins build up to form structures called ‘plaques and tangles’
- this leads to nerve cell death
- a progressive disease, over time, more parts of the brain are damaged
symptoms of AD
early
- confustion
- problem finding right word
- loss of interest
- blame others
middle
- frequently confused/disoriented
- mood swings
- help with daily care
late
- require great deal of help
- extreme memory loss
- weight loss or overeating
- loss of speech
- vast individual differences -
onset of AD
- a neuropsychological elements consisting of amnesia and 1 or more of
- aphasia
- apraxia
- agnosia
diagnosing AD
- history
- cognitive tests
- physical exam
- brain scan
cause of AD?
- no single factor causing AD
- likely a combination of factors
- age
- genetics
-environmental
-lifestyle
amyloid cascade hypothesis
- two hallmark pathologies identified in AD
- b amyloid peptide
neurofibillary tangles - an excess AB triggers disease
neurotransmission
chonlinergic hypothesis
- AD treatment target ACh receptors
ACh neurotransmitter release - GABA - attention
- Glutamate - memory consolidation
risk factors of AD
age
- greatest risk for dementia
- risk due to other are realated factors
- high blood pressure
changes in nerve cells
genetics
- APOE gene - influence AD
environmental
- pollution - 11% of dementia cases
- health/medical history
- social activity and mental activity - reduce risk
MCI and stats
- mild cognitive impairment
- the presence of cognitive abnormality greater than expected in relation to age and education
- according to Alzheimer’s society - between 5-20% of 65+ have MCI
MCI, Permanent?
- it can be transitory with normal functional integrity resuming
- some can have permanent MCI
types of MCI
- amnesic mild cognitive impairment
- amnesic multi-domain mild cognitive impairment
- non-amnesic mild cognitive impairment
diagnostic criteria for MCI
- decrease in short or long term memory
- preserved daily living
- difficult to diagnose
characterized with subtle changes in
- day to day memory
-perception
- language
- planning
methods used to diagnose MCI
memory clinic
- lab tests
- history
- medical exam
- MRI scan
Issues with diagnosing MCI
sensory impairment
vision
- poor sight - poor neuropsychological test performance
hearing
- old might miss hear questions
individuals differences not taken into account
why is accurate diagnosis of MCI important
- identify people at risk of dementia
- ensure available treatment
- plan ahead
- understand characteristics
MCI - early signs of dementia
- for some, MCI is a prodromal stage of dementia - lifestyle choices can affect development of AD
- but not everyone with MCI develop dementia
risk factors/ influences of MCI
- several bio-psycho-social factors that influence
- age
- biological - blood pressure
- psychological - depression
- social - life events
MCI - linking brain and behaviour
- the fornix - implicated in episodic memory
- in MCI tissue volume was reduced in the fornix
- shift in memory load
- we could potentially use fornix volume as a biomarker of MCI
the earlier the better - pre MCI
- memory complaints may be associated with later development of MCI or AD
Fjell 2014
“it will be difficult to understand AD without understanding why it affects older brains”
- we can not understand AD until we understand ageing better
typical progression of AD symptoms
- changes in behavior in cogntive takes 20 years to develop
- not necessarily true, not all older adults have dementia
AD biomarkers
show us a window into the brain changes
- CSF
show us AD pathology
invasive
- PET
pick up metabolism and glucose function
expensive - limited
-FDG-PET
indicator of synaptic activity
can not directly detect core pathological features
-MRI
see fine details of grey and white matter
a late event
can not detect core pathological features
treatment of AD
in absence of cure, attempts are made to delay progression
- lifestyle interventions
- restoring plasticity
- reducing pathology with drug treatments
drug treatments for AD
- donepezil
- rivastigmine
- galantamine
treat symptoms of mild and moderate AD - lacanemab
slower the decline in humans
are interventions to minimize AD worthwhile
implementing can reduce the prevalence of dementia
prevalence dementia - UK
- going up
- roughly doubles every 5 years
dementia prevalence - china
- as it becomes more ‘westernized’ dementia is increasing
- going up in terms of obesity and smoking - a link to lifestyle factors
- almost tripled between 1990 and 2010
