Alzheimer's disease is a type of dementia that affects memory, thinking, and behavior. It is a progressive disease that worsens over time and eventually leads to death. The most common cause of Alzheimer's disease is aging. As people age, they are more likely to get Alzheimer's disease than younger people. Alzheimer's disease is not contagious or inherited from parents. However, there are certain changes in the brain that can make it more likely for someone to develop Alzheimer's disease later in life. The severity of the symptoms varies from person to person. Some people may only have mild symptoms while others may have severe symptoms such as memory loss and confusion about their surroundings or other people around them.

The most severe cases can lead to death due to complications such as infections or malnutrition due to forgetting how or being unable to eat on their own.