Life Span Development

Cognitive Deficits of the Elderly

(Alzheimers)

Orientation

The most common form of dementia (about half of cases worldwide) is Alzheimer’s disease (AD), a disorder characterized by the proliferation of plaques and tangles, certain abnormalities in the cerebral cortex that destroy brain functioning. Plaques are formed outside the brain cells from a protein called B-amyloid; tangles are a twisted mass of protein threads within the cells. In AD, these plaques and tangles usually begin in the hippocampus, the brain region where most memory functions occur.

Alzheimer’s disease (AD)   The most common form of dementia, characterized by gradual deterioration of memory and personality and marked by plaques of B-amyloid protein and tangles in the brain. Alzheimer’s disease is not part of the normal aging process.

New techniques for analyzing brain tissue (the only sure way to diagnose AD) show that the amount of plaques and tangles correlates with the degree of intellectual impairment before death but not with the victim’s age. Because the analysis of brain tissues can occur only after death, typically a diagnosis is based on reports of symptoms, a medical history, and some cognitive tests. This method is about 85 percent accurate, although autopsies find plaques and tangles in the brains of some very old people who did not have AD symptoms.

Risk Factors for Alzheimer’s Disease

Gender, ethnicity, and especially age affect a person’s odds of developing Alzheimer’s disease. Most studies find that women are at greater risk than men. Alzheimer’s is less common in Japan and China than in North America and Europe, and less common among Americans of East Asian descent than among those of European descent (Jellinger, 2002). It may also be less common in Africa, but low life expectancies there mean that relatively few reach late adulthood, so the low rates of AD may be the result of people dying before they develop the disease.

For everyone, everywhere, age is the chief risk factor for AD. According to a compilation of 13 studies from several nations (Ritchie et al., 1992), the incidence rises from about 1 in 100 at age 65 to about 1 in 5 over age 85. Other research finds that the incidence doubles every five years after age 65, with about half of those over age 100 having the disease (Czech et al., 2000; Samuelsson et al., 2001).

As you learned, Alzheimer’s is partly genetic (Selkoe & Podlisny, 2002). When AD appears in middle age, the person has the chromosomal abnormality called trisomy-21 or has inherited at least one of three genes: APP (amyloid precursor protein) gene, presenilin 1, or presenilin 2. In such cases, the disease usually progresses quickly, reaching the last phase within three to five years. This early AD is unusual. Most cases begin in late adulthood and take 10 years or more to progress from first symptoms to final stage (Wilson et al., 2000).

Especially for the elderly, another gene called ALZHS, or a variant of the ApoE gene (allele 4) increases the risk. A person who inherits ApoE4 from one parent, as one-fifth of all people in the United States do, has about a 50/50 chance of developing Alzheimer’s by age 80. People who have the gene from both parents usually develop Alzheimer’s if they live long enough, although ApoE4 increases the risk of heart disease and stroke, so many such people die before dementia begins. Nevertheless, a few people with the double allele reach age 100 and still do not have Alzheimer’s, so ApoE4 is not used diagnostically before symptoms appear.

Genes can also make Alzheimer’s disease less likely. Another allele of the same gene, ApoE2, dissipates the amyloid protein that causes plaques. Lifestyle may also decrease the risk, with physical exercise and mental activity said to be protective. There is an allele that protects people from Arctic weather and reduces the risk of Alzheimer’s, although it increases the risk of some other diseases (Ruiz-Pesini et al., 2004). People with no known genetic or environmental risk can develop AD, a fact that actually provides hope: “Given that AD is a condition involving multiple genetic, environmental, and pathological factors, there may be many therapeutic strategies that will be useful for delaying or slowing dementia” (Vickers et al., 2000).

Stages: From Confusion to Death

Alzheimer’s disease usually runs through a progressive course of five identifiable stages, beginning with general forgetfulness and ending in total mindlessness.

Stage One

The first stage is characterized by absentmindedness about recent events or newly acquired information, particularly the names of people and places. A person in the first stage of the disease might be unable to remember where he or she just put something or forget people’s names after being introduced to them. In this early stage, most people recognize that they have a memory problem and try to cope with it, writing down names, addresses, appointments, shopping lists, and other items much more often than they once did.

This first stage is sometimes confused with normal aging, but recent research finds that it can be distinguished from the normal decline in explicit memory (Peterson, 2003). Failure to remember a common word is a notable sign. One woman described the problem:

There is embarrassment when I want to say “ocean” and I can’t think of the word. It depends on how comfortable I am with the person I’m talking with. Then I can ask, “What’s that big water thing?” and they’ll guess, “The ocean?” Then I say, “Oh, yeah.” [Snyder, 1999]

Stage Two

In the second stage confusion becomes more generalized, with noticeable deficits in concentration and short-term memory. Speech becomes aimless and repetitious, vocabulary is much more limited, and words get mixed up. A person might say tunnel when he means bridge, for instance. Someone at stage two is likely to read a newspaper article and forget it completely the next moment, or to put down her keys or glasses and within seconds have no idea where they could be. If certain people are suspicious by nature, with Alzheimer’s they may accuse others of having stolen what they themselves have mislaid and forgotten. Then, “in the firm conviction of having been robbed, the patient starts hiding everything, but promptly forgets the hiding place. This reinforces the belief that thieves are at work” (Wirth, 1993).

Personality changes are common, as long-standing impulses become more pronounced when rational thought loses control. A person given to tidiness may become compulsively neat; a person with a quick temper may begin to display explosive rages; a person who is asocial may become even more withdrawn.

Memory loss in the second stage is sufficiently severe that people may forget they have a memory problem. Typical is the case of a man who, in stage one, began to run into financial problems because of his fading memory. In stage two, he was forced to turn over all his financial decisions to others, having no responsibility beyond putting his signature on documents. When asked if he was depressed, he replied that he didn’t have any reason to be. He knew that he had had problems in the past, but now, he said, “I sign the papers. I’m in charge” (Foley, 1992).

Stage Three

In the third stage, memory loss becomes truly dangerous. Individuals can no longer manage their basic daily needs. They may take to eating a single food, such as bread, exclusively, or they may forget to eat entirely. Often they fail to dress properly, or at all, going out barefoot in winter or walking about the neighborhood naked. They are likely to turn away from a lit stove or a hot iron and forget about it, creating a fire hazard. They may go out on some errand and then lose track not only of the errand but also of the way back home. And they cannot ask neighbors for help because they do not recognize them. Getting lost is a serious and valid fear of people in this stage (Sabat, 2001).

For some people with Alzheimer’s, visual recognition is a major problem. The particular part of the brain that looks at an object and realizes that it is a K, a hat, or a person may become tangled. The person appears more helpless and more incompetent than the overall cognitive losses would indicate.

Stage Four

By the fourth stage, people need full-time care. They cannot care for themselves or respond normally to others, sometimes becoming irrationally angry or paranoid. At the end, they can no longer put even a few words together to communicate. They cannot recognize even their closest loved ones. This is not necessarily because they do not remember them at all, but because the part of the brain that recognizes objects and faces has further deteriorated. A man might demand to see his wife but refuse to believe that the person before him is, indeed, his wife.

Stage Five

In the fifth stage, people no longer talk, failing to respond with any action or emotion at all. Death usually comes 10 to 15 years after the beginning of stage one (Fromholt & Bruhn, 1998).

Assignment

Answer the following questions (feel free to share more) after your visits:

What is AD? Is there more than one variety of this disease?

What are the warning signs of AD?

What are the major symptoms of AD?

How is AD usually diagnosed?

What causes AD? What areas of the brain are affected by AD?

In your observation of Alzheimer patients, what stages were they in? What symptoms did they exhibit?

List ten simple ways to help an Alzheimer’s family.