Lecture 21 - Dementia Flashcards
what are signs and symptoms of dementia?
loss of cognitive ability, changes not associated with normal ageing and generally associated with progressive neurodegeneration within the brain.
forgetting names and everyday objects, feeling anxious depressed or angry, a decline in the ability to walk, write or read, confused in familiar environment
what is the mild stage of cognitive impairment in dementia?
increasingly noticeable memory loss, cognitive impairment.
has ability to cover this up
may be normal ageing in older people
what is moderate stage of cognitive impairment in dementia?
memory lapses and confusion becomes more obvious.
personality and mentala bilgy changes, some physical problems may develop.
repeated reminders for everyday functions - eat, toilet etc
what is the sever stage in cognitive impairment of dementia?
Memory & personality deteriorate further.
Impaired ability to communicate.
Become dependent on others
what are causes of dementia?
alzeihemers, dementia with leeway bodies, Parkinson’s, vascular dementia, frontotemporal dementia, mixed dementia and many more
who is dementia more prevalent with?
65% of people living with dementia are women.
what are ways for dementia diagnosis?
mini mental state examination
memory impairment screen
mini-cog
eight time informant to differentiate ageing and dementia
what are dementia associated disease and their diagnosis/
Alzheimer’s disease (AD)
NB: early onset AD (4%): Progressive decline in cognitive ability
Regular visits to GP and Memory clinics
No definitive diagnostic test
Postmortem associated with plaques (amyloid) and neurofibrilliary tangles (tau)
Vascular dementia:CT or MRI scans
Reduced blood flow to brain
Able to rule out other conditions that may have similar symptoms
Dementia with Lewy Bodies:SPECT scan – more sensitive than CT & MRI
Neuronal deposits of α-synuclein
CT or MRI scans to rule out other conditions that may have similar symptoms
Frontotemporal dementia
(FTD):Usually affects people 45-64 yrs old.
CT or MRI scans to identify damage to frontal and temporal lobes.
Tauopathy
what is the problem in the brain with alzeihmers disease?
plaques around neurons: extracellular and tangles within neurons: intracellular
what are the physiological roles of amyloid and tau?
amyloids:
angiogenesis, vascular plug.
antimicrobial peptide
tumour suppression
aids recovery after injury
neurogenesis/ survival
regulates hyperexcitability
learning and memory
tau:
promotes myelination
iron homeostasis
insulin signalling
what goes wrong in amyloids that causes dementia?
there is incorrect cleavage of amyloid precursor protein (APP) by secretases. APP ceased beta secretase followed by gamma secretase = Abeta = toxicity
what goes wrong of tau that causes dementia?
hyper polarisation of tau.
usually not highly phosphorylated and does not aggregate
tauopahties linked to many disease
FTD ia a taupathy - 10% linked to single gene mutation eg MAPT
current interest in hypnotic spread of tau
what are the risk factors alzeihemrs disease?
age: 60-64 1%, 80-84%
genes - ApoE4 - role in fat metabolism found primarily im astrocytes.
0 copies at 75 yrs old – 6%
1 copy at 75 yrs old – 11%
2 copies at 75 yrs old – 18%
what are treatments to target mild to moderate AD stage?
first line: AchE inhibitors: donepezil, rivastigmine, galantamine
dosage:Donepezil (Aricept, Eisai/Pfizer) 5mg daily at bedtime
Increased to 10mg after 1 month if no side effects
Undesirable effects include diarrhoea, muscle cramps, fatigue, nausea, vomiting and insomnia
what are treatments to target see ad stage ?
frist lien are Non-competitive
NMDA antagonist
memantine.
memantine can be given in moderate AD if AchE inhibitors are not tolerated
dosage:
5mg once daily
Increased weekly to max 20mg
Undesirable effects include dizziness, headache, constipation, somnolence and hypertension
