Lecture Five Flashcards
Risk of having Alzeimer’s
1 in 1000 before the age of 65
After 65 the risk increases doubles after every 5 years.
1 in 5 have it over the age of 80
42% of people in the uk have friends or family with AD
What is Alzeimer’s disease characterised by?
Loss of brain cells with consequent shrinkage of brain
Psychological symptoms e.g. Memory and thinking
Average 7-8 years before death
Can last for 3 to 20 years
How are plaques formed?
In the normal brain alpha secretese snips and releases APP therefore releasing a fragment further gamma secretese releases another snippet. These go off and benefit the neurons.
In Alzeimer’s patients beta sectrese releases beta APP and the gamma secretes releases the second snippit. This causes the fragments to join together and become toxic therefore forming plaques.
How are tangles formed?
In a normal brain tau is made which stabilises structures and is critical for internal transport . Nutrients and other cargo are carried within the neuron up and down structures called microtubcles.
In Alzeimer’s diseases patients the Tau breaks off and breaks the microtubcles causing them to fall apart. The bits of Tau then join together and form tangles. Therefore disabling the transport system and destroying the cell.
Stage one of dementia
Memory loss 1. Episodic memory 2. Semantic memory Problems thinking and making decisions e.g. Making/deciding a meal Can live independently with support.
Second stage of dementia - moderate
Confusion Disorientation in time and space Poor judgment Apathy about life and condition Neglect of appearance and Hallucinations Disturbed sleeping patterns
Symptoms of severe dementia
Forget their own identity
Don’t recognise other people
Unable to communicate
Loss over bodily functions
Famous sufferers of Alzeimer’s
Ronald Reagan
Harold Wilson
Iris Murdoch
Scores and meaning on the MMSE
Maximum score is 30
Mild dementia 21-26
Moderate dementia 10-20
Severe dementia less than 10
What’s atrophy?
As neurons die the brain shrinks
In the early stages of AD the brain shows…
Reduced levels of glucose (sugar providing energy for the cells)
Reduced levels of neurotransmitter that neurons use to communicate with each other e.g. Acetylcholine, dopamine and glutamate.
What is the overall effect of reduced glucose and neurotransmitter levels?
Accompanying cell death and reduction in activity levels within the brain.
What is Wernickes-Karsakoffs encephalopathy?
Memory loss with confabulation seen in patients with chronic alcoholism.
