Recognizing the symptoms

Alzheimer's disease usually is not diagnosed in the early stages, even in people who visit their primary care doctors with memory complaints. One reason is that people and their families generally underreport the symptoms. They may confuse them with normal signs of aging. Or the symptoms may emerge so gradually that the person affected doesn't recognize them or goes to great lengths to conceal them.

Recognizing symptoms early is crucial because the sooner a diagnosis is made, the more able doctors are to slow cognitive decline. Early diagnosis also allows the individual and his or her family members to plan for the future. If you or a loved one is experiencing any of the following symptoms, contact a physician.

Progressive memory loss

This is the hallmark of Alzheimer's disease. Initially, only short-term memory is impaired, and the person merely seems forgetful. But because short-term memory is essential for absorbing new information, the impairment soon interferes with the ability to interact socially and perform one's work. Long-term memory may be retained longer, often in great detail, but it becomes fragmented as the disease progresses. Toward the final stage, people with Alzheimer's may be unable to recall their own names.

Decline in cognitive abilities

These are the "thinking" activities of reasoning — solving problems, making decisions, exercising judgment, and so on. Impairments of cognitive function can begin subtly as poor performance in an activity the person once did well. Poor judgment and lack of insight can lead to accidents.

Early in the disease, individuals may easily lose track of time; later, their disorientation becomes more pronounced and extends to places and people. The sense of time becomes more distorted as the disease progresses, and people may insist it's time to leave immediately after arriving at a place or may complain of not having been fed as soon as a meal has ended.

Changes in mood and personality

These changes are often the most convincing evidence for families that something is wrong. Apathy is common, and many individuals lose interest in their usual activities. A person may become withdrawn, irritable, or inexplicably hostile.

Depression may also accompany Alzheimer's, partly as a result of chemical changes in the brain caused by the disease itself and partly as an understandable psychological reaction to the loss of mental abilities. Symptoms of depression include loss of interest in previously enjoyable activities, change in appetite that sometimes leads to weight loss or gain, change in sleeping pattern (either insomnia or oversleeping), loss of energy, and feelings of worthlessness. People with Alzheimer's, though, seldom have feelings of excessive guilt or thoughts of suicide, which are often symptoms of depression.

Aphasia

This is the medical term used to describe an impairment in using and understanding language. Because speaking, writing, reading, and understanding speech involve different areas of the brain and different nerve networks, aphasia can be uneven, with some skills retained longer than others. For example, a person may be able to recognize written words flawlessly and yet fail to comprehend their meanings.

Typically, aphasia begins with word-finding difficulties. Unable to think of the right words, a person may try to cover up with long-winded descriptions that fail to reach the point, or he or she may angrily refuse to discuss the matter further. Substituting a similar-sounding word ("wrong" instead of "ring") or a related word ("read" instead of "book") is common. The person may ramble, stringing phrases together without expressing any real thought, or may forget all but a few words (which patients sometimes repeat over and over). In many cases, all language abilities are lost as dementia becomes severe, and individuals become mute.

Agnosia

The ability to process sensory information deteriorates, causing agnosia, a disorder in perception. Unable to comprehend the meaning of what they see, people with agnosia may run into furniture. They may believe a spouse is an impostor, become frightened by ordinary sounds, or fail to recognize their own reflection in a mirror. Agnosia can contribute to inappropriate behavior, such as urinating into a wastebasket.

Apraxia

The inability to perform basic motor skills such as walking, dressing, and eating a meal is known as apraxia. This is quite different from weakness or paralysis caused by a stroke. A person with apraxia has literally forgotten how to perform these activities. Usually, apraxia develops gradually, but in some cases, it begins abruptly. Apraxia may first be evident in fine hand movements, showing up in illegible handwriting and clumsiness in buttoning clothing, but eventually the ability to chew, walk, or sit up in a chair is lost.

Behavior problems

Troublesome changes in behavior are a common feature of the disease. Examples include being stubborn, resisting care, refusing to give up unsafe activities, pacing or hand-wringing, wandering, using obscene or abusive language, stealing, hiding things, getting lost, engaging in inappropriate sexual behavior, urinating in unsuitable places, wearing too few or too many clothes, eating inappropriate objects, dropping lit cigarettes, and so on. A particular behavior can disappear as a patient's abilities further deteriorate (for example, verbal abuse declines as aphasia progresses), only to be replaced with new problems.

Catastrophic reaction

A strong emotional response to a minor problem is another symptom of the disease. Catastrophic reactions can involve crying inconsolably, shouting, swearing, agitated pacing, refusing to participate in an activity, or striking out at another person. The usual triggers include fatigue, stress, discomfort, and the failure to understand a situation. Essentially, a catastrophic reaction is the response of an overwhelmed, frightened person who feels cornered and is trying to protect him- or herself. The behavior is caused by brain dysfunction and is mostly beyond the person's control.

Sundowning

This term refers to behavior problems that worsen in the late afternoon and evening. No one knows exactly why sundowning occurs, but there are several theories. Because people are tired at the end of the day, their tolerance for stress declines, and a minor problem can generate a major outburst. An already confused person may be overstimulated when several people are in the house, dinner preparations are under way, and the television is on. Dim light may also contribute to a person's misinterpretation of visual information.

Review Date: 2007-01-01

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