Cognitive impairment Flashcards
1
Q
What is dementia?
A
- A set of symptoms that include the progressive loss of memory, mood changes, and problems with communication and reasoning
- There are many types of dementia any of which will affect the normal functioning of the brain
- As of 2015, there are approx 850,000 people living with dementia in the UK
2
Q
Symptoms of Alzheimer’s: Early/mild
A
- Lapses of memory, confusion
- Problems finding the right words, repetition
- Slower at grasping new ideas
- Find it harder to make decisions
- Loss of interest in other people or activities
- Blame others for taking mislaid items
- Unwilling to try new things/adapt to change
3
Q
Symptoms of Alzheimer’s: Middle/Moderate
A
- Frequently confused/disoriented in time and space / forget names of people. places, appointments and recent events
- Experience mood swings, scared and frustrated by their increasing memory loss
- Become more withdrawn due to loss of confidence or communication problems
- Difficulty carrying out everyday activities
- Need help with managing their daily care
4
Q
Symptoms of Alzheimer’s: Late/Severe
A
- require a great deal of help, become totally dependent on others for care
- Very pronounced loss of memory –> can’t remember close family members
- Increasingly frail/shuffling, falls, unsteady walking, confined to bed or wheelchair
- Difficulty in eating and swallowing
- Weight loss or over-eating
- Incontinence
- Loss of speech
- Restlessness
- Distressed/aggressive
5
Q
What is vascular dementia?
A
- Associated with stroke damage. The affected brain cells are deprived of oxygen, producing regionally specific deficits
- Vascular dementia can progress in a ‘stepped’ manner - symptoms may suddenly worsen due to strok and then be stable until another stroke occurs. If someone has no more strokes than their symptoms may not get worse
- Unlike AD, those with vascular dementia can be more aware of their condition and are more prone to depression than those with AD
6
Q
What is frontotemporal dementia?
A
- Damage to the frontal and/or temporal lobes of the brain –> areas responsible for behaviour, emotional responses and language skills
- In the early stages, memory for recent events may be unaffected but there are other changes
1. Uncharacteristic selfishness/unfeeling/rude/loss of inhibition
2. Easily distracted - Ritualised behaviour/compulsions
- The first indication may be issues with recalling the names of objects and comprehending words (semantic dementia) or with producing fluent speech (progressive non-fluent aphasia)
- In later stages, symptoms are more similar to those of AD
7
Q
What is dementia with Lewy Bodies?
A
- Microscopic deposits (Lewy bodies) can be found in the brain that produce degeneration and death of nerve cells. Many people with this form of dementia also develop signs and symptoms of Parkinson’s disease e.g.
1. Slowness of movement, tremors, falls
2. Difficulty in judging distances
3. Visual hallucinations/paranoia/delusions - Unlike AD, in the early stages of Lewy body dementia, the abilities of the affected person can fluctuate drastically from day to day or even within a single day
- In later stages, symptoms are often very similar to those of AD
8
Q
What is mild cognitive impairment?
A
- The presence of acquired cognitive abnormality greater than expected in relation to age and education in the absence of dementia and detrimental effects upon activities of daily living
- Between 5-20% of older people (65+) have MCI
9
Q
What is subjective cognitive concerns?
A
- No formal diagnosis, as neuropsychological assessment appears normal, but a subjective feeling that decline is greater than expected for a given age
- Concerns regarding memory impairment predict dementia onset
10
Q
What are the neural indicators for the onset of AD?
A
- Neurodegenerative and progressive
- Abundance of plaques and tangles (amyloid and tau)
- Reduction in neurotransmitters (acetylcholine, glutamate, GABA)
11
Q
Grey matter volume in relation to AD
A
- Abnormal change is characterised by widespread volume reductions in temporal, parietal and frontal structures
- However normal ageing also results in volume reductions in these regions
- Abnormal changes in GM occur earlier than those in WM
- Entorhinal cortex and hippocampal atrophy best define AD in comparison to controls but atrophy occurs even in those identified as low risk for developing AD
- Atrophy takes place at a much higher rate in MCI and AD
12
Q
Can grey matter volume predict the onset/progression of cognitive impairment?
A
- Hippocampal volume in MCI predicts progression to Alzheimers as does volume of the posterior cingulate
- Longitudinal data suggests that lateral temporal cortex and precuneus volume characterise those who progress from MCI to AD
- A meta-analysis comprising 960 AD and 1195 controls found that patients had considerably smaller volume in limbic regions
- In addition, there were GM decreases in right fusiform gyrus and right superior frontal gyrus
13
Q
Risk factors: age
A
- Age is the greatest risk factor for dementia
The increased risk may be due to factors associated with ageing:
- Higher blood pressure
- Increased incidence of heart disease and stroke
- Weakening of the body’s natural repair systems
- Changes in the immune system
- Changes to nerve cells, DNA, cell structure e.g. age-related breakdown in the protective membranes of neurons can increase the likelihood of developing AD
14
Q
Risk factors: Age-related hypertension
A
- Grey matter in dlPFC, PPC, and hippocampus appears to be vulnerable to hypertension due to decreased blood flow, which contributes to atrophy
- Hypertension is also a predictor of the presence of white matter hyperintensities, primarily in frontal and parietal regions
- In animal models, hypertension produces excess amyloid beta
- Those who are cognitively normal but have a genetic risk of AD and also high BP show elevated amyloid deposits
- A 25% reduction in hypertension could reduce AD cases by 400,000
15
Q
Risk factors: Genetics
Apolipoprotein E (APOE) and related alleles
A
The influence of inherited genes for late-onset AD is relatively small (compared to the genetic predisposition in early-onset AD):
- APOE ⍷2 - rare (7%), protective?
- -> If AD occurs, it usually develops much later in life - APOE ⍷3 - the most common allele (79%)
- -> neither decreases nor increases risk - APOE ⍷4 - increases risk for AD, earlier onset (14%), cumulative risk –> far more likely to develop AD
