What is Alzheimer's Disease?
The above video informs us about what Alzheimer's is, the stages of the disease and some history of where it first came from.
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Alzheimer's Disease is the most common form of dementia. Up to 70 percent of people that have dementia disease also develop Alzheimer's Disease. Alzheimer's Disease is when neurons are damaged in the brain, resulting in impaired memory, thinking and behavior. This condition can be divided into different sub-groups; Sporadic Alzheimer's Disease and Familial Alzheimer's Disease. Sporadic Alzheimer's disease can affect adults at any age, but usually occurs after the age 65 and is the most common form of Alzheimer's Disease. Familial Alzheimer’s Disease is a very rare genetic condition, caused by a mutation in one of several genes and because it is in the presence of mutated genes. This means that the person will eventually develop Alzheimer's disease at a faster/ younger age, usually in their 40's or 50's.
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Who is Most Vulnerable?
In Australia 80% of people with dementia will develop Alzheimer's Disease. You are more likely to be diagnosed with Alzheimer's Disease after the age of 65 but with Alzheimer's Disease, the build up of Beta Amyloid or Amyloid Beta can start almost 10 years in advance so by the time you are diagnosed with the disease it is to late to be reversed.
Diagnosis
At this point in time there are only two accurate ways of diagnosing Alzheimer's Disease and neither of these are really convenient for the sufferer of the disease. There are also number and memory tests. The issue with these tests are that they can be extremely subjective and someone who is not actually being affected by the disease could get wrong. This basically means they are inaccurate and not a real indicator of someone who is suffering from Alzheimer's Disease. The other two methods of diagnosing Alzheimer's Disease accurately are either a PET (Positron Emission Tomography) scan or an CSF (Cerebrospinal Fluid Analysis) test. Both of these tests are unrealistic for patients to be tested monthly for a diagnosis of the disease. This could mean a build up of Amyloid Beta occurs, and by the time symptoms of the disease show, the toxic protein has already been building up in the brain for about ten years and is past a treatable point where it can be slowed down or cured.
PET: The way a PET scan works is by having a radioactive tracer injected into the person. This tracer acts like an dye which bonds to the Amyloid Beta protein in the brain. The person is then scanned under a PET scanner which shows an image of the brain. The difference is that because of the radioactive tracer the Amyloid beta is highlighted and shown in cases where it may not usually have been able to be identified without this highlighting the Amyloid Beta. This means that doctors can accurately diagnose a patient with the disease. The issue with PET scans is that they cost $2000 per scan and they are sending radiation through the human body. Although this is at a extremely low level, there is always a risk that a cell could mutate and, the scan that was supposed to help you, could end up creating a mutant cell which could become a cancer cell or another disease. CSF: A CSF or Cerebrospinal Fluid Analysis is an analysis of the fluid which surrounds your spinal cord. This procedure is called a Lumbar Puncture. This procedure is done using a needle about the thickness of a pencil and pushing it into your spinal region. About 1 mL of this Cerebrospinal fluid is withdrawn using a syringe. This fluid is then examined and Alzheimer’s can be diagnosed. This is all done while the patient is conscious and and the risk factor involved is extremely high. This is because the needle is in a region that if the smallest mistake is made or the person moves/twitches the tiniest bit they would become a paraplegic as this region is extremely sensitive. This treatment is cheaper than a PET scan costing the patient $350 but it is extremely risky. |
This is a graph that shows that by the time a patient develops the symptoms for Alzheimer's the toxic protein for Amyloid Beta has already built up and its to late.
This is a PET scanning machine.
This is a comparison to a normal brain and a brain from a person who has Alzheimer's Disease using a PET scan. The Amyloid Beta has been identified by the yellow colour.
This is showing that the fluid for CSF comes from around the spinal cord.
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What Causes Alzheimer's Disease?
Like all types of dementia, Alzheimer's Disease is caused by the death of brain cells like neurons. Neurons are nerve cells which die over time from age. These neurons do not reproduce or grow back. Once the neurons in the brain die the messages in the brain cannot be sent to one another if the neurons are dead.
Beta Amyloid is a toxic protein that blocks communication between neurons, engulfing them and eventually destroying them. Beta Amyloid comes from a normal protein and is called Amyloid Precursor Protein in its normal state, before mutation. The normal proteins mutate into toxic proteins when the DNA is copied into RNA and a mistake or a mutation is made in the copy of RNA. Beta Amyloid is on the membrane of the cell and is involved with metabolizing and lipids (roles inside a cell). Beta Amyloid destroys the waste removal systems and ends up engulfing and destroying the neurons. This Beta Amyloid has been found to be related to Alzheimer's Disease but research is still being done to refine these findings.
Neurofibulary Tangles in the brain have been found to be made up of a protein called Tau. The brains nerve cells contain a network of tubes which act like a highway for food molecules among other things, usually the Tau protein ensures that these tubes are straight which then allows the molecules to pass through freely. However in Alzheimer's Disease these proteins collapse into twisted strands or tangles, making the tubes disintegrate which then obstructs nutrients from reaching the nerve cells, leading to cell death.
Beta Amyloid is a toxic protein that blocks communication between neurons, engulfing them and eventually destroying them. Beta Amyloid comes from a normal protein and is called Amyloid Precursor Protein in its normal state, before mutation. The normal proteins mutate into toxic proteins when the DNA is copied into RNA and a mistake or a mutation is made in the copy of RNA. Beta Amyloid is on the membrane of the cell and is involved with metabolizing and lipids (roles inside a cell). Beta Amyloid destroys the waste removal systems and ends up engulfing and destroying the neurons. This Beta Amyloid has been found to be related to Alzheimer's Disease but research is still being done to refine these findings.
Neurofibulary Tangles in the brain have been found to be made up of a protein called Tau. The brains nerve cells contain a network of tubes which act like a highway for food molecules among other things, usually the Tau protein ensures that these tubes are straight which then allows the molecules to pass through freely. However in Alzheimer's Disease these proteins collapse into twisted strands or tangles, making the tubes disintegrate which then obstructs nutrients from reaching the nerve cells, leading to cell death.
Symptoms
The symptoms of an Alzheimer's Disease patient are mainly the lapses in memory and difficulty to find the right words for everyday objects. However, the symptoms of an Alzheimer's Disease patient will vary depending on how far the disease has progressed, how fast it is spreading throughout the brain and the parts of the brain that are affected.
Other symptoms may include:
Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and eventually the ability to carry out the simplest tasks.
Alzheimer's Disease affects your sense of orientation. Patients may recall their name, the year of their birth and the address of a home they lived in years ago however they may think that the current year is 1954.
An Alzheimer's Disease patient may walk outside on a cold winter's night in simply their pajamas with no slippers with no sense of danger to him or herself.
Other symptoms may include:
- Persistent and frequent memory difficulties, especially of recent events. It affects your memory; even events from a few moments ago may be soon quickly forgotten, however a person with Alzheimer's Disease may recall detailed events of World War II with ease.
- Vagueness in everyday conversation.
- Apparent loss of enthusiasm for previously enjoyed activities.
- Taking longer to do routine tasks.
- Forgetting well-known people or places.
- Inability to process questions and instructions.
- Deterioration of social skills.
- Emotional unpredictability, someone with Alzheimer's Disease who used to be a kind and caring person may become increasingly rude or obnoxious.
Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and eventually the ability to carry out the simplest tasks.
Alzheimer's Disease affects your sense of orientation. Patients may recall their name, the year of their birth and the address of a home they lived in years ago however they may think that the current year is 1954.
An Alzheimer's Disease patient may walk outside on a cold winter's night in simply their pajamas with no slippers with no sense of danger to him or herself.
Stages of Alzheimer's Disease
1. The disease first starts in the Hippocampus (which is located below the Thalamus which is near the brain stem in the mid brain), this is the part of the brain where memories are formed and that is why short term memory loss is one of the first signs of the disease.
2. The proteins then aggressively invade the other parts of the brain resulting in unique symptoms for each. Next, in the frontal lobe the proteins disable the ability to process logical thoughts. 3. After this the proteins move to the part of the brain which control emotion, this can lead to erratic mood changes. 4. Next, at the top of the brain, the proteins cause hallucinations and paranoia. 5. Once they reach the rear of the brain the plaques and tangles work aggressively together to erase the minds deepest memories. 6. Eventually the control centers of the brain controlling heart rate and breathing are overpowered as well, resulting in death. |
Treatments
At this point in time there is no cure for Alzheimer's Disease however as the average life expectancy of humans is rising every year more and more research and funding is being put into finding a cure.
The treatment for Alzheimer's Disease is much the same as Parkinson's Disease in the way that both diseases are currently incurable. There are currently drugs which prolong the effects of Alzheimer's Disease on the brain slowing memory loss and the confusion that comes with the disease. These drugs don’t 100% fix the disease but are just a temporary solution. |
Difference Between Dementia and Alzheimer's
Dementia is a syndrome or a group of symptoms that consistently occur together and it is not a specific disease. The term ‘dementia’ is used to describe a set of symptoms that can include, memory loss, difficulty thinking, problem solving or language issues. Dementia is caused by damage to the brain cells, and because Alzheimer's is a disease that destroys the brain, it is one of the most commons forms of dementia. As many as 50 to 70 percent of all dementia cases are caused by Alzheimer's, although, other conditions can cause dementia such as Parkinson's disease.
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History
Alzheimer's Disease was first recorded in 1907 by Dr Alois Alzheimer. Dr Alzheimer reported the case of a middle-aged woman, Auguste Deter, with dementia and specific changes in her brain. However for only the next 60 years Alzheimer’s disease was considered a rare condition that affected people under the age of 65. It was not until the 1970s that Dr Robert Katzman declared that "senile dementia" and Alzheimer’s disease were the same condition and that neither were a normal part of ageing.