Alzheimer's Disease - Symptoms

The earliest symptom of Alzheimer's disease is memory loss. Older people often worry that they may have AD because they forget more easily. But memory loss by itself is not an indication that a person has Alzheimer's disease. Some memory loss is a natural part of growing old.

With AD patients, however, memory loss is progressive and, eventually, so serious that they cannot function normally. In the early stages, memory loss may simply mean that the person has forgotten where he or she left the

Diseased brain tissue from an Alzheimer's patient showing senile plaques, seen as darker spots surrounded by lighter halos. (Photograph by

Cecil Fox/Science Source

. Reproduced by permission of the

National Audubon Society Collection/Photo Researchers, Inc.

)

car keys. Over time, the problem becomes so serious that he or she can no longer remember where the car is parked or how to drive it.

As AD progresses, other symptoms appear. Patients can no longer perform routine tasks, like tying shoes or eating. Many patients develop sleep disorders or become confused or disturbed in the evening. These symptoms are sometimes referred to as "sunsetting." In the final stages of the disease, patients have problems eating, communicating with others, and controlling their bladder or bowels.

Other forms of mental disorders can cause any of these symptoms. In fact, about 20 percent of those who are first suspected of having AD turn out to have some other disorder. For that reason, it is essential that a person who experiences any of the symptoms discussed see a doctor for a thorough examination.