ALZHEIMER'S DISEASE

ALZHEIMER'S DISEASE

By
Dr. Mohamed Magdi Elgadi
Los Angelos, CA

Alzheimer's disease is the most common cause of dementia in elderly people. It is a devastating disease that impairs, reasoning, motor skills, and ability to take care of oneself. Although the risk of getting the disease increases with age, it is not a normal part of aging. It is estimated that currently 4.5 million people in the United States have Alzheimer's disease, and by the year 2050 the number of Americans with Alzheimer's disease could range from 11.3 to 16 million.

History: Symptoms of Alzheimer's disease were first identified by the German psychiatrist Emil Kraepelin, but the neuropathology was identified by his colleague, the German psychiatrist Dr. Alois Alzheimer. Dr. Kraepelin made a generous decision that the disease would bear Alzheimer's name.

Causes and Diagnosis:No one knows what causes Alzheimer's disease, and no definitive test to diagnose the disease in living patients. However, the disease can be diagnosed with up to 90% accuracy based on the clinical information obtained from neuropsychological tests, such as memory test, problem-solving, and language tests. Unfortunately, no blood or urine test currently known that can detect or predict Alzheimer's disease.

Risk factors:The genetic factors are now put into consideration, especially after researchers found a high incidence of Alzheimer's disease in patients with Down syndrome (or as used to be called in some countries Mongolism).
Environmental factors, though not definitive, are being looked-into as a culprit in the affected individuals, where autopsy showed that albumin, zinc and other metals were detected in the brain tissue of Alzheimer people.
However, it isn't known till now if they cause the disease or they build up in the brain tissue as a result of the disease.
Other factors being taken into consideration are viruses that might cause the changes seen in the brain tissue of Alzheimer patients, but these are not definitive and still being studied. The only known risk factors taken into consideration are age and family history.

Serious head injury may be also considered as a risk factor. Most probably several factors together may react differently in each person to initiate the disease process. The disease affects age group of 65 years or over. About 1 in 10 of those over 65 have the disease, and 50% of those over 85 have the disease of Alzheimer.

Clinical Features:The typical symptom of Alzheimer's disease is progressive and chronic memory loss. Behavioral changes my include confusion, disorientation, periods of defiance, abusive behavior, violence, etc. The course of the disease and the rate of decline varies from one person to an other, but the duration from onset of symptoms to death is 5 to 20 years.

Pathology:The major pathological changes are seen in the brain tissue, usually at autopsy. There is loss of nerve cells in the cerebral cortex, and deposition of protein outside the cells in the form of amyloid forming what is known as diffuse plaques. Accumulation of an abnormally phosphrylated form of protein inside the nerve cells in the brain as paired helical filaments known as Alzheimer's neurofibrillary tangles. Accumulation of amyloid in the walls of small blood vessels in the brain termed amyloid angiopathy. Loss of synaptic contacts between neurons due to cell adhesions with proteins. Diffuse neuropathy from death and loss of nerve cells in the brain that ends in atrophy of the affected area and enlargement of the brain ventricles.

Treatment and Prevention:There is no known cure for Alzheimer's disease, although there are some drugs used to alleviate some of the symptoms of the disease such as Acetylcholinesterase inhibitors since there is a selective loss of the cholinergic neurons in the forebrain as a result of the disease. Acetylcholinesterase inhibitors reduce the rate at which acetylcholine is broken down and hence increase the concentration of Acetylcholine in the brain (combatting its loss caused by death of cholinergic neurons. Although these drugs do not prevent the disease progression but they seem to moderate the symptoms.
Example of these drugs include: Rivastigmine, Galantamine, Donepezil, and Tacril (Tacril is no longer in use).

Many studies have indicated that the use of non-steroidal anti-inflammatory drugs (NSAIDs) such as Ibuprofen (Motrin, Advil), seem to significantly slow the progress of the disease and dramatically decrease the risk of the disease in those who have not yet developed it. Aspirin in large daily doses reduce the risk of developing the disease but to a lesser degree than with NSAIDs (Motrin, Advil).
Daily use of either of NSAIDs or Aspirin can put the individual at a greater risk of developing stomach ulcer and potentially fatal bleeding.

A significant study on Alzheimer's disease in 2004, has reported that a combination of vitamins E and C, over the time, sharply reduced the risk of developing Alzheimer's disease (a reduction up to 80%), but only if the dose of vitamin E is 400 IU and that of vitamin C is 500 mg or more.
Some studies suggest that the ratio of at least 1000 mg vitamin C and 400 IU of vitamin E are ideal. Other studies show that quitting smoking, weight reduction, regular physical exercise and avoidance of diabetes and hypertension can also reduce the risk.
In one study, dancing appeared to be the only exercise effective in reducing the risk of developing Alzheimer's disease.

Vaccine:There are ongoing tests of a vaccine for Alzheimer disease. This was based on the idea that if we could train the immune system to recognize and attack the beta-amyloid plaques, the immune system might reverse the deposition of amyloid and stop the disease. However, when the first vaccine was used in humans, a small fraction of the participants developed brain inflammation, and so the trials were stopped, but those participants were followed up, and found to have slower progression of the disease. It is hoped that researches will provide a better vaccine in the future that can be of use for families with history of Alzheimer's disease.

Famous Alzheimer's Sufferers:- Late president Ronald Regan- Charlton Heston- Ralph Waldo Emerson- Iris Murdoch- Rita Hayworth- Barry Goldwater- James Doohan

References:- Internet resources- Principles of Internal Medicine, by Harrison- Alzheimer's Association, and periodicals