Changes in the brain
Several changes occur in the brains of people with Alzheimer's disease. The brain cells shrink or disappear, and are replaced by dense, irregularly-shaped spots, or plaques. Another indicator of the disease is thread-like tangles within existing brain cells. These tangles eventually choke healthy brain cells.

Symptoms
Alzheimer’s disease symptoms include a gradual onset and continuing decline of memory, changes in judgment or reasoning, and an inability to perform familiar tasks.

Effects of Alzheimer’s disease
Over time, Alzheimer's disease will impact every aspect of a person's life: how he/she thinks, feels and acts. It is difficult to predict the symptoms each person will have, the order they will appear or the speed of the disease’s progression. However, it is certain that a person’s mental abilities, emotions and moods, behaviour, and physical abilities will eventually all be affected.

Although the disease results in changes, it does not affect the person’s ability to appreciate, respond to and experience feelings such as joy, anger, fear, love or sadness.

Once brain cells are damaged by Alzheimer’s disease they cannot be restored, but there are treatments and strategies that can help both the person with the disease and the caregiver.

At present, there is no known cure for Alzheimer’s disease.

Alzheimer’s disease and heredity
Sporadic Alzheimer Disease is the more common form of the disease and accounts for 90 to 95 percent of all cases. The role of heredity in Sporadic Alzheimer's Disease is unclear and continues to be the subject of intense research.

Familial Autosomal Dominant (FAD) Alzheimer Disease is a rare form of the disease and accounts for 5 to 10 per cent of all cases. It is known to be inherited and can pass directly from one generation to another.

The cause of Alzheimer’s disease
We still don’t know what causes Alzheimer’s disease or how to stop its progression.
Researchers believe there is no single cause of the disease, rather a combination of factors such as family history, the external environment, and the internal environment within a person’s body.