Lecture 21: Dementia Flashcards
What are the signs and symptoms of dementia?
- Loss of cognitive ability
- Changed not associated with normal aging
Give examples of changes not associated with normal ageing
- Struggling to remember recent events but easily rememember things from the past
- Finding it hard to follow conversations or shows on TV
- Forgetting the names of friends or everyday objects
- Problems with thinbking and reasoning
- Repeating yourself or losing the thread of what you are saying
What are the stages of cognitive impairment in dementia?
Mild
- Increasingly noticeable memory loss, cognitive impairment.
- Has ability to cover this up.
- May be normal ageing in older people
Moderate
- Memory lapses and confusion becomes more obvious.
- Personality and mental ability changes, some physical problems may develop.
- Repeated reminders for everyday functions – eat, toilet etc
Severe
- Memory & personality deteriorate further.
- Impaired ability to communicate.
- Become dependent on others
What are the causes of dementia?
- A;zheimers disease
- Parkisons disease
- Dementia with lewy bodies
- Vascular dementia
- Mixed dementia
- Frontotemporal dementia
How is dementia diagnosed?
- Mini mental state examination (MMSE)
- Memory Impairment Screen (MIS).
- Mini-CogTM.
- Eight-item Informant Interview to Differentiate Aging and Dementia (AD8).
Can be used to differentiate between normal ageing and dementia.
How is alzheimers disease diagnosed?
- 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)
How is vascular dementia diagnosed?
- CT or MRI scans
- Reduced blood flow to brain
- Able to rule out other conditions that may have similar symptoms
How is dementia with lewy bodys diagnosed?
- 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
How is Frontotemporal dementia
(FTD) diagnosed?
- Usually affects people 45-64 yrs old.
- CT or MRI scans to identify damage to frontal and temporal lobes.
- Tauopathy
What are common features found in many demntia patients?
- Brain shrinkage
- Plaque like deposits
- Neurofibrilliary bundles.
- beta amyloid in plaques
- tau in neurofibrilliary tangles
What can be seen in the brain of patinents with alzheimers disease?
Plaques (amyloid beta protein) around neaurons: extracellular
Tangles within neurons (Tau protein): Intracellular
What are the physiological roles of amyloid?
- Angiogenesis
- Vascular plug
- Antimicrobial peptide
- Tumour suppression
- Aids recovery after injury
- Learning and memory
- Regulates hyperexcitability
- Neurogenesis/ survival
What are the suggested physiological roles of tau?
- Iron homeostasis
- Transcription
- Protects DNA
- Chromosome segregation
- Insulin signalling
- Axon transport
- Microtubule protection
- Microtubule dynamic/ growth cone
- Neurogenesis/ synaptogeneisis
- Motor control
- Sleep wake cycle
- Anxiety
- Learning and memory
- Permits hyperexcitability
- Promotes myelination
What goes wrong in dementia?
- Incorrect cleavage of amyloid precursor protein (APP) by secretases causing toxcity
- Hyperphosphorylation of tau: Usually not highly phosphorylated & does not aggregate
What are the risk factors for alzheimers disease?
Age
- 60-64 1%
- 80-84 11%
Genes
ApoE4 –role in fat metabolism found primarily in astrocytes.
0 copies at 75 yrs old – 6%
1 copy at 75 yrs old – 11%
2 copies at 75 yrs old – 18%
