Alzheimer's disease

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at February 3, 2016
StartAlzheimer's disease

Alzheimer’s disease is the most common type of dementia, accounting for up to 80 percent of diagnoses. It is a chronic and fatal neurological disorder that attacks memory and cognition.

Contents

Definition & Facts

Researchers believe that autoimmune inflammation leads to brain cell destruction. Although there is no definitive test for Alzheimer’s in living patients, there are hallmarks that result in a probable diagnosis. The most obvious proof is the presence of plaques and tangles in the brain's cells. Plaques are bundles of beta-amyloid, a protein. Tangles are twisted microscopic threads of tau protein. Presently, physicians can only find these features at autopsy. Doctors now diagnose patients by their typical behavior.

Symptoms & Complaints

The most common sign of Alzheimer's is memory loss. At first, it is mild and can cause individuals to forget small details, such as where they left their keys or the remote control. After some time, possibly several years, symptoms will worsen. Patients may have unexplained mood swings and disorientation.

It is not uncommon for someone with dementia to be in the middle of an activity and forget where they are and what they are doing there. As the disease worsens, patients are likely to forget their family and friends, including children and spouses. They may know who their loved ones are one minute and have a spell where they forget and begin to panic. Other symptoms of Alzheimer's include the following:

If a person suspects that their loved one may be suffering from the onset of dementia, it's important to seek immediate medical treatment. However, not all cases of mild memory loss point to Alzheimer's disease; it is common for people to become forgetful as they age.

Causes

While family history does not mean that a person will definitely suffer from the disease, genetics does seem to be a factor. There is a gene, APOE-e4, that is the first identified for causing Alzheimer’s. From the research so far, the protein beta-amyloid is thought to be the primary reason for the death of brain cells.

Since the disease is typically seen in the elderly, age is also considered to be a factor in causing dementia. After 65 years, the risk for the disease doubles every five years. Those older than 85 have a 50 percent risk of the disease. In addition, scientists believe that suffering from traumatic brain injuries may contribute to the eventual onset of dementia.

Diagnosis & Tests

Currently, the best way to diagnose the Alzheimer's is to measure intellect and memory. Specially trained psychologists use several tests that point to the development of Alzheimer’s even before symptoms appear. The paired-associate learning test challenges people to recall both related and unrelated pairs of words. Another test is for perceptual identification. The person taking the test reads aloud words that briefly appear on a computer screen. The tester then repeats only some of those words to achieve ‘priming,’ that in normal people would result in a better score due to increased familiarity. Those with Alzheimer’s show no difference in recalling primed and non-primed words.

The third test is a visual association that presents line drawings that are paired illogically with others. When a person performs poorly, it indicates that there is a problem with episodic memory. The last is a dichotic listening test. Information is spoken through headphones separately through the left and right ears. The right ear is the standard learning path to the brain. Alzheimer’s patients have a more difficult time processing data presented through the left ear because they have an impaired ability to switch pathways.

Treatment & Therapy

At the moment, there is no cure for Alzheimer’s disease. However, the current FDA-approved drugs are useful in treating the problems with thinking and memory in about half of patients. They do not treat the cause nor do they cure the disease. The aim of the drugs under development is to change the disease process itself. The current thinking is that not one, but a combination of medicines may be more efficient, much as current ‘drug cocktails’ now treat AIDS and some cancers.

Addressing the recently identified culprit of the protein components of brain plaques that contribute to Alzheimer's is under intense study. Two enzymes, beta-secretase and gamma-secretase, separate the protein fragment from its parent compound. Blocking this action at several different points and using antibodies against the proteins are primary research goals. The prevention of the tau protein is also under scrutiny.

Addressing the typical neurological inflammatory feature of Alzheimer’s also holds great promise. The beta-amyloid and tau proteins cause an inflammatory response in the brain that causes the cell damage leading to disability and death. Insulin resistance is also a characteristic feature of Alzheimer’s disease and drugs are in development. Insulin resistance in an older person may signal the need for further neurological testing.

Cholinesterase inhibitors are used to improve communication between cells in the brain. Another drug, memantine, helps slow the progression of the disease in patients with moderate to severe Alzheimer’s symptoms.

In addition to drugs, there are natural treatments that can help, including a healthy diet and regular exercise. Since affected individuals suffer from memory loss and disorientation, they often forget to eat. Therefore, caregivers should ensure that Alzheimer’s patients drink plenty of water and eat meals and snacks that are high in protein. Fruit and vegetable juices are also a great source of nutrition.

Individuals with dementia should avoid drinking caffeinated beverages. Mild cardio workouts, such as walking or riding stationary bikes, can help patients sleep better and lower their chances of constipation. Additionally, certain vitamins and vitamin supplements are recommended by doctors as forms of treatment. These include vitamin E, fish oils, curcumin, and ginkgo.

Prevention & Prophylaxis

Current clinical trials are trying to identify which individuals with certain genetic traits will go on to develop the disease. Other studies are trying new drugs that may prevent or slow the disease.

Research has found that about 80 percent of Alzheimer’s patients have cardiovascular diseases such asd diabetes, high cholesterol or high blood pressure. These conditions are a threat to the body as well as to the brain of those patients and the issues need to be addressed both with lifestyle changes and appropriate pharmaceuticals. A healthy diet, exercise and healthy social connections may help avoid dementia and improve the quality of life of all older individuals.