In 1906, Alois Alzheimer first described a neurological disorder of the brain associated with global deterioration of cognitive functioning and resulting in severe social impairment. Once thought rare, senile dementia of the Alzheimer’s type is the most commonly acquired progressive brain syndrome. Alzheimer’s disease begins with insidious intellectual and memory loss as the brain becomes shrunken from nerve cell loss and advances over 5 to 15 years to a chronic vegetative state. Progressive cognitive, psychological, and social dysfunction has a profound effect on family and friends. Alzheimer’s disease is associated with significant morbidity, and it may be the fourth leading cause of death in the United States (Katzman 1976). D. K. Kay and colleagues (1964) showed the average survival for demented men to be 2.6 years after the diagnosis of illness, whereas the survival period for nondemented men of the same age was 8.7 years. However, there is great variability in survival statistics from different studies.

Although Alzheimer’s disease is the leading cause of dementia, its etiology remains unknown, and treatment is supportive. The illness is a major problem among the elderly. Approximately 4 percent of the population over the age of 65 is affected, and by age 80, prevalence reaches 20 percent (Brodie 1982). As the elderly population of the United States increases, the number of persons with Alzheimer-type dementia will also increase. Alzheimer’s disease exists in the presenium, but it has been difficult to document a bimodal distribution with regard to age. Even though pathological changes in presenile and senile forms of the illness are similar, there is evidence that early- and late-onset Alzheimer-type dementia differ clinically (Seltzer and Sherwin 1983).