Case 8 Dementia Flashcards
(44 cards)
How do neurons communicate?
- Neurotransmitters (chemicals) released so a message can pass from one synapse to another dendrite to another neuron.
- Have twice number of synapses if we are adults.
- Connections changing every day in brain. Ability of brain to adapt = plasticity
What is dementia?
- Dementia –> decline in cognitive abilities that are significant enough to interfere with daily life activities
- Dementia = syndrome (expressed in every person in different ways, different symptoms, different behaviours, etc)
- progessive condition = symptoms get worse over time.
What are the different types of dementia?
- Alzheimers
- Vascular dementia
- Lewy body
- Frontotemporal dementia
- Mixed dementia
- Late onset dementia (65+ yrs)
- Early onset dementia (<65 under age)
What is alzheimers?
brain disorder that slowly destroys memory & thinking skills & ability to carry out simple tasks.
What is vascular dementia?
caused by brain damage resulting from restricted blood flow in the brain.
What biomarkers are involved with dementia?
- Neurofibrillary tangles (tau)→ within the cells
- Amyloid plaques (amyloid beta) → sit between cells
How does beta amyloid form?
- Amyloid beta normally originates from protein APP.
- protein normally split into enzymes & then normally 40 amino acids.
- But in alzheimer’s split into 42 amino acids.
How does the amyloid plaque form?
Additional 2 amino acids = clumping of beta-amyloid
What happens with amyloid in alzheimers?
- Communication between cells disrupted due to the accumulation of amyloid beta.
What is the hippocampus and why is it important?
- Important for consolidation from short term –> long term memory which is why people with dementia have a lot of memory problems because information is not stored in long term memory.
- In advanced alzheimer’s disease brain, hippocampus almost immediately gone = almost no informed is stored in long term memory.
What are the early symptoms of dementia?
- forgetfulness
- losing track of time
- becoming lost in familiar places, etc.
What are the middle stage symptoms of dementia?
- becoming forgetful of recent events and people’s names
- becoming lost at home
- communication problems
- needing help with personal care
- behaviour changes, etc.
What are the late stage symptoms of dementia?
- unaware of time & place
- difficulties recognizing loved ones
- difficulty walking, aggression
- increasing need for assisted self-care, etc.
What are non-modifiable risk factors for dementia?
- Age
- Sex
- Family history
- Genetics - does not run in families due to genetics but runs in family because age is most important risk factor and we are getting older and older??? - genes of how old you get
What are modifiable cardiovascular risk factors for dementia?
- Hypertension
- Obesity
- High cholesterol
- Diabetes type 2
What are modifiable lifestyle risk factors for dementia?
- Excessive alcohol consumption
- Physical inactivity
- Smoking
- Unhealthy diet
- Low mental stimulation
- Sleep problems
What are modifiable psychosocial risk factors for dementia?
- Loneliness / social network
- Mood / depression
What are other modifiable risk factors for dementia?
- Air pollution
- Low educational level
- Hearing loss
- Traumatic brain injury
*How is dementia a clinical syndrome?
- Dementia = clinical syndrome. (see image)
- Subjective complaints → self reported memory complaints (mention everything they forget = nothing wrong)
- Objectified impairment in 1 cognitive domain → e.g. memory or information processing speed but still can daily function - not everyone in this stage will develop dementia
- Dementia - objectified impairments in multiple domains. interference in daily life
What is cognitive reserve?
mind’s and brain’s resistance to damage of the brain
What happens if you have a high brain reserve with dementia?
- Develop dementia more slowly than people without this type of BR
- High BR can compensate damage to the brain network
- patients with high CR may be able to process tasks in a way that allows to better cope with brain damage and/or can sustain greater degrees of brain damage before demonstrating functional deficits.
What are reserve-enhancing factors?
- Exposure to reserve-enhancing factors over lifespan → reduced risk of dementia
- Physical exercise
- Intellectual stimulation (e.g. education)
- Leisure activities
When does brain reserve decrease?
BR decreases with ageing due to e.g. wear & tear (oxidative stress) and reduced ability to form synapses (coupling unit between neurons) → brain becomes less plastic
What is the incidence of alzheimers?
- Prevalence is increasing but incidence is decreasing in high income countries → how?
- Theory = incidence (# of new cases) every year is much smaller than years before but still total # is still increasing but number of new cases is little lower. → why?
- Theory that it is due to having higher educational levels than generations before us, more busy with lifestyles, CVD risk factors are better under control than generations before us (e.g. hypotensive medications, CVD risk managements, etc)