What It Is and What It Is Not
Alzheimer's disease, which accounts for more than half of all the victims of organically caused memory loss, is named for the German physician Alois Alzheimer, who first described the disease in the early 1900s. He identified a presenile form of the illness occurring in people as young as age 30. Later research found that a milder but more common form of the disease affected older people. Today, Alzheimer's disease is labeled senile dementia -- Alzheimer's type, generally abbreviated SDAT.
Alzheimer's disease is the fourth most prevalent cause of death -- after heart disease, cancer, and stroke. Death certificates now denote Alzheimer's disease as the cause of death; as with cancer, it is failure of an organ (the brain in this case) that causes death. In the past deaths from Alzheimer's disease were usually ascribed to pneumonia. The life expectancy of an Alzheimer's patient is reduced by up to one-third when matched for age to other elderly people.
The loss of intellectual abilities is of sufficient severity to interfere with everyday social and occupational functioning. The victim's capacity to think abstractly is impaired; he is unable to find similarities and differences between related words and has trouble defining words and concepts. His judgment is also impaired. There may be disturbances in language (aphasia), an inability to carry out motor activities (apraxia), or a failure to recognize or identify objects despite intact sensory and motor