Alzheimer's disease  is a progressive, irreversible brain disease that destroys memory and thinking skills. Estimates vary, but experts suggest that as many as 5.1 million Americans has the disease, which affects people of all racial, economic, and educational backgrounds. Although Alzheimer's primarily affects people age 60 or older, it also may affect people in their 50s and, rarely, even younger.
Alzheimer's disease is the most common cause of dementia in adults. Dementia  is a loss of memory and intellect that interferes with daily life and activities. Dementia is not a disease; rather, it is a group of symptoms that may accompany certain diseases and conditions. Other symptoms include changes in personality, mood, or behavior.
Other causes of irreversible dementia include vascular dementia  and alcohol abuse . The recommendations in this booklet deal primarily with common problems in Alzheimer's, but they also may be helpful for people with other types of dementia.
There is no "typical" person with Alzheimer's. There is tremendous variability among people with Alzheimer's in their behaviors and symptoms . At present, there is no way to predict how quickly the disease will progress in any one person or the exact changes that will occur. We do know, however, that many of these changes will present problems for caregivers. Therefore, knowledge and prevention are critical to safety.
People with Alzheimer's disease have memory problems and cognitive impairment (difficulties with thinking and reasoning), and eventually they will not be able to care for themselves. They often experience confusion, loss of judgment, and difficulty finding words, finishing thoughts, or following directions. They also may experience personality and behavior changes . For example, they may become agitated, irritable, or very passive. Some people with Alzheimer's may wander from home  and become lost. Others may not be able to tell the difference between day and night—they may wake up, get dressed, and start to leave the house in the middle of the night thinking that the day has just started. People with Alzheimer's also can have losses that affect vision, smell, or taste.
These disabilities are very difficult, not only for the person with Alzheimer's, but for the caregiver, family, and other loved ones as well. Caregivers need resources and reassurance to know that while the challenges are great, specific actions can reduce some of the safety concerns that accompany Alzheimer's disease.