Alzheimer's disease is a progressive disease that destroys memory and other important mental functions. It's the most common cause of dementia a group of brain disorders that results in the loss of intellectual and social skills. These changes are severe enough to interfere with day-to-day life.
Alzheimer's disease (AD), also known as Alzheimer disease, or just Alzheimer's, accounts for 60% to 70% of cases of dementia. It is a chronic neurodegenerative disease that usually starts slowly and gets worse over time. The most common early symptom is difficulty in remembering recent events (short-term memory loss).