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. In most people with Alzheimer’s, symptoms first appear in their mid-60s. Alzheimer’s disease is the most common cause of dementia among older adults.
Alzheimer's is not normal aging. Alzheimer's is a disease.
The disease is named after Dr. Alois Alzheimer. In 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems, and unpredictable behavior. After she died, he examined her brain and found many abnormal clumps (now called amyloid plaques) and tangled bundles of fibers (now called neurofibrillary, or tau, tangles).
These plaques and tangles in the brain are still considered some of the main features of Alzheimer’s disease. Another feature is the loss of connections between nerve cells (neurons) in the brain. Neurons transmit messages between different parts of the brain, and from the brain to muscles and organs in the body.
Although treatment can help manage symptoms in some people, currently there is no cure for this devastating disease.
About 1 in 8 people age 65 and over has the disease.
People who get Alzheimer's disease are usually older, but the disease isn’t a normal part of aging. Scientists aren’t sure why some people get it and others don’t. But they do know that the symptoms it causes seem to come from two main types of nerve damage: