Diseases - Alzheimer's Disease: Curious Patterns

Alzheimer's Disease was the 8th leading cause of death in 1999. More than 44,500 people died of AD that year. The disease properly belongs on the graphic of the previous panel, but this disease has a curious pattern and history and is thus best treated as a separate topic.

In a sense Alzheimer's also belongs among the "new" diseases (see Emerging Diseases: Many Pathways in this chapter). Dr. Alois Alzheimer, a German physician, initially described it in 1906. It has come to be known as the leading cause of dementia — a term that generally describes symptoms of a decline in a person's ability to think, remember, make judgments, produce speech, and generally to function normally. Although the graphic shows a steep rise in the AD death rate for the most affected age groups (some- what understated by the use of a logarithmic scale here — to show the data clearly), the disease has not grown quite as dramatically as might appear — except in recognition.

AD cannot be confirmed with certainty except by autopsy. Dementia, generally, means that brain function is impaired — which causes death by other means. The underlying cause, which may be Alzheimer's, has not made it on the death certificates as often in the past as it does today — now that the disease has become well known by the medical community.

The incidence of the disease, however, is also growing in absolute terms, not simply because it is better recognized and reported. It is a disease of advanced old age, as the graphic shows: those 85 and older are much more likely to die of the disease. People are living longer — women longer than men. The disease is more prevalent among women. We are seeing here one of the curious by-products of an extended life expectancy. As people survive to higher and higher ages, they are more likely to die of Alzheimer's disease than of disease now being brought under better and better control — like heart disease and stroke.

AD comes in an "early onset" and a "late onset" variety. Early-onset AD is traceable to inherited genetic traits. Symptoms begin to manifest before age 60. Late onset AD is more common; the genetic transmission is less clear. At present the disease is not preventable and has no cure.

The disease may last from three to 20 years. If it is of long duration, it imposes heavy costs — economic and emotional — on the families in which the sufferer lives. The rising incidence of this disease in the future is a certainty — unless breakthroughs produce a cure or, possibly, a vaccine (one is under test). A future social trend may well be an increase of those who experience the disease at second hand — watching the slow deterioration of a once vital and vibrant human being.

Source: Centers for Disease Control and Prevention. National Center for Health Statistics. National Vital Statistics System. Online. Available: http://www.cdc.gov/nchs/default.htm, May 29, 2002. For background and support, contact Alzheimer's Association. Online. Available: http://www.alz.org.