Currently, it is estimated that as many as 5.2 million people in the U.S. have Alzheimer's disease.1 This number is expected to grow over the next 50 years as the population ages and life span increases.2
Alzheimer's disease is the most common type of dementia. It is a progressive and degenerative disease, which means that it gets worse over time.
When someone has Alzheimer's disease, nerve cells die in areas of the brain that are vital to memory and other mental abilities, and connections between nerve cells are disrupted. There are also lower levels of some of the chemicals in the brain that carry messages back and forth between nerve cells. This affects memory, judgment, and thinking, which in turn may hinder a person's ability to handle day-to-day activities.
Through research, we are learning more about how Alzheimer's affects the brain. We do not yet know how to prevent or cure it, but we do know how to treat its symptoms.
It is not known what causes Alzheimer's disease. Researchers suspect that it could be caused by a factors that affect each person differently.2 While the scope of those factors is not completely known, age is the main risk factor.
Alzheimer's disease affects three percent of the population between the ages of 65 and 74. But estimates suggest that 19 percent of those older than 75 years and 47 percent of those older than 85 years have the disease.3