What is Alzheimer's disease?
Alzheimer's disease is a progressive disorder that slowly kills nerve cells in the brain. First identified in 1907 by the German physician Alois Alzheimer, the illness afflicts some 4 million Americans today. At least one in 20 adults aged 65 and older suffers from the disease; one study found that some 47 percent of those over age 85 have Alzheimer's disease.
Symptoms
At first, people suffering from Alzheimer's disease develop almost imperceptible personality changes and memory loss. They seem more easily tired, upset, or anxious. Their memory loss differs from normal age-related memory problems (see chart A). They can't cope well with change: they can follow familiar routes but traveling to a new place confuses them and they easily become lost. They grope for the words they want in conversation. Often, they try to cover up their memory lapses by denying forgetfulness or by blaming it on events or people.
Later, memory losses worsen, and Alzheimer's patients may repeatedly ask the same questions. They can't make good decisions but may become angry when family members try to help with such accustomed tasks as balancing the checkbook or filling out tax forms. Driving becomes more dangerous, because they can't react quickly or appropriately to traffic dangers, and the freedom to operate a motor vehicle may become a thing of the past. At this stage, people with Alzheimer's disease begin to forget the names of longtime friends. Social life becomes more difficult, and they may become more isolated.
In the early stages of their illness, people with Alzheimer's disease are particularly susceptible to depression. Their condition may also be aggravated by reactions to medications or an unsuitable living environment, and the erosion of their intimate relationships may increase their suffering.
Dementia-a syndrome characterized by deterioration of reasoning, judgment and impulse control as well as changes in memory and personality-becomes more apparent in the next stage. A number of illnesses may cause dementia, but among older people Alzheimer's disease is the most common cause. People afflicted with dementia lose the ability to read words or music. They can no longer identify the date or season. As they lose recent memory, they seem to lose entire blocks of time, forgetting, for instance, who the current president is. Emotional problems may become more severe as the person with Alzheimer's disease tries to make sense of failing reality. They may have long crying spells, become increasingly agitated, anxious, suspicious, and develop paranoid notions about things being stolen or hidden, or about their food being poisoned. Their sleep may be disrupted, and they may wander at night.
In later stages, people with Alzheimer's begin to lose physical coordination and need help with dressing and bathing. More and more often, they can't identify their family and friends, though they may still smile, laugh and enjoy company. Physical impairments can increase until walking is impossible. Eventually, the Alzheimer's patient completely loses touch with reality, and requires constant care.
Reversible Dementias
Anyone who suspects a loved one may be suffering from Alzheimer's disease should not jump to conclusions too quickly. Many other illnesses mimic Alzheimer's disease. Physicians must rule out these treatable conditions before diagnosing Alzheimer's disease. They include:
- Depression
- Reactions to medications or to drug interactions with other medicines
- Chemical imbalances, caused by poor nutrition or illnesses such as pernicious anemia (vitamin B12 deficiency), diabetes, an imbalance of sodium or calcium, or decreased or increased thyroid levels
- Heart and lung problems that deprive the brain of adequate amounts of nutrition or oxygen
Not all true dementias are caused by Alzheimer's disease. Brain damage caused by impaired circulation-called multi-infarct dementia-causes between 12 and 20 percent of dementia in older people. Other conditions, including multiple sclerosis, Parkinson's disease, Huntington's disease, and Creutzfeldt-Jakob disease, also cause progressive dementia.
Diagnosing Alzheimer's Disease
Research on Alzheimer's disease has established that all people with the disease develop characteristic microscopic changes in the brain, called "plaques" and "neurofibrillary tangles" which develop as brain cells die. The ultimate reason for the premature death of brain cells isn't yet known. However, because plaques or tangles develop deep within the brain, doctors don't normally test for them. As a result, physicians must carefully review a person's symptoms and take a thorough medical history. Psychiatrists and other physicians will only diagnose probable Alzheimer's disease after a thorough medical, psychiatric and neurological evaluation has ruled out other conditions that mimic the disease. At the best established medical centers with Alzheimer's disease specialty programs, clinical diagnosis can be quite accurate-90 percent or better.
Research Looks for Causes
The tangles and plaques of Alzheimer's disease appear inside the nerve cells in large numbers in parts of the brain that regulate thinking, learning, sleep, and memory. When magnified, these tangles look like pairs of filaments that have been twisted around each other. The plaques are made of a protein called amyloid which is surrounded by what appear to be debris from dying cells.
Psychiatric researchers have focused on amyloid in plaques because this protein has been associated with several other diseases such as tuberculosis, Hodgkin's disease and cancer. Some researchers think amyloid regulates growth in nerve cells and could be part of the cells' attempts to defend themselves. Others have found that abnormal proteins associated with amyloid are toxic to nerve cells. They think amyloid may contribute to brain cells' death. Finally, researchers have found amyloid in the skin and intestines of some Alzheimer's disease patients, but not in healthy people, leading some doctors to hope they may some day diagnose Alzheimer's disease by detecting amyloid in other parts of the body.
Other studies also have focused on imbalances in calcium. If Alzheimer's disease changes the calcium regulatory system, it may cause too much calcium to build up in brain cells and, eventually, kill them. Also, the presence of abnormally high concentrations of aluminum in the brain tissues of some with Alzheimer's disease has led some researchers to investigate a possible link. Researchers speculated that aluminum-ingested along with food and drinks stored in aluminum cans-might be causing or aggravating the illness. Research has suggested, however, that if there is any connection, it probably stems from Alzheimer's disease making brain tissues more permeable to aluminum, rather than from aluminum causing the illness.
Still other studies have found imbalances of certain brain chemicals called neurotransmitters. People suffering from Alzheimer's disease have low levels of the neurotransmitter acetylcholine, which are critical to the proper functioning of memory, thoughts and other higher intellectual functions. Alzheimer's patients also have low levels of serotonin, the neurotransmitter that regulates aggression, mood and sleep. Scientists think a serotonin imbalance could contribute to the sleep disturbances, mood changes and aggressive behavior that appear in some Alzheimer's patients.
Finally, researchers have found that some Alzheimer's disease victims have low levels of norepinepherine in their brains. Deficiencies in this neurotransmitter can contribute to anxiety, depression, excessive sleepiness, and difficulty in focusing attention.
Treatments May Be on the Horizon
What do these findings mean? Some have guided studies to develop medicines that alleviate symptoms of Alzheimer's disease by bringing acetylcholine, serotonin or norepinepherine back into balance.
Scientists have seen mixed results in medications' ability to halt the progression of Alzheimer's disease. Some increase the amount of acetylcholine in the brain, but offer only modest improvements in mental alertness and memory. Others keep existing acetylcholine from degenerating, improve visual and verbal memory and help certain types of learning.
More recently, researchers have learned that a chemical known as Alcar (acetyl-l-carnitine) imitates the action of acetylcholine in rats and seems to slow the death rate among nerve cells. While it is too early to tell if this avenue of research will lead to a treatment, Alcar studies are continuing in the U.S. to learn whether it can reduce Alzheimer's symptoms.
Coping: A Team Approach Works Best
Even though scientists don't fully understand how Alzheimer's disease begins and what causes its symptoms, patients and their loved ones can do much to cope with the illness and its effects.
Choosing Your Physician
One of the most important steps is finding a qualified physician. Older people have special health needs, so family members should seek medical care from a physician who understands and has expertise in the health of the elderly. The doctor may be a primary care physician, a neurologist or a psychiatrist who has an interest in geriatrics.
A psychiatrist is often the first choice when Alzheimer's disease begins with its prominent changes in personality, mood, or behavior. As a medical doctor with specialized training in the diagnosis and treatment of mental and emotional illness, a psychiatrist also knows how to identify physical ailments that may require attention from other physicians. A psychiatrist can also identify and treat major depression, an illness that is common among Alzheimer's victims and their families (see Chart B). If unrecognized and untreated, depression can mimic or intensify other problems. A psychiatrist can modify treatment to meet each individual's needs.
In addition, psychiatrists have expertise in prescribing and monitoring psychiatric medications that help manage the behaviors that can develop from Alzheimer's disease. The prescription written by the psychiatrist or other physician is designed to control symptoms without causing unnecessary side effects. Families should make sure they understand why these medications are prescribed and which side effects to watch for and report.
Symptoms of Depression That Can Mimic or Complicate Alzheimer's Disease:
- Unexplained weakness or fatigue
- dizzy spells
- low energy
- Stomach aches
- indigestion
- constipation
- urinary disturbances
- Change in eating habits
- appetite and weight
- Sleeping disturbances
- Slowed or more agitated movement
- Slowed speech
- softened lowered or monotone voice
- incomplete responses
- Feelings of tension
- anxiety
- irritability
- Loss of initiative
- inability to enjoy activities once enjoyed
- Indecisiveness
- apathy
- boredom
- indifference
- Poor attention and concentration
- Tendency to cry and become upset over minor issues and events
- low self-esteem
- feelings of worthlessness
- hopelessness
- helplessness
- inappropriate guilt
- Thoughts of suicide
Check-List of Alzheimer's Disease Symptoms
- Loss of short term memory occurs: person can't learn new information
- Loss of long-term memory occurs: person can't remember personal information such as birthplace or occupation
- Judgment is impaired
- Aphasia develops: patient can't recall words or understand the meaning of common words
- Apraxia develops: patient loses control over muscles and can't, for example, button shirts or operate zippers
- Patients lose spatial abilities and can't assemble blocks, arrange sticks in a certain order or copy a three-dimensional figure
- Personality changes: patient may become unusually angry, irritable, quiet, confused
Counseling and Support Are Vital
Psychiatric medications should not be the only treatment. Both patients and loved ones may need the help of support groups and counseling.
By taking advantage of group support, education and-if needed-psychotherapy, patients and loved ones can prepare themselves for the disease and its progression. They can learn ways to manage the emotional and behavioral changes that accompany this disease. For example, they can learn to alleviate negative behavior by responding to the underlying causes, such as fear or low self-esteem. They can also identify and cope better with feelings of loss and grief related to permanent changes in a loved one's function and personality.
A person suffering from Alzheimer's disease and his or her family or friends should not feel they must cope with this illness alone. Numerous organizations across the country provide friendship, support, and fellowship. Community resources can help patient and family as they struggle with the emotional and behavioral roller coaster, the medical and social service maze, and the legal and financial intricacies that accompany Alzheimer's disease.
With proper diagnosis and intervention, Alzheimer's disease patients and their loved ones can help prolong the time during which people with Alzheimer's can enjoy productive, fulfilling lives. With a solid understanding of the illness, the patients and their loved ones can cope more effectively with the symptoms and avoid some of the complications that may come with the disease's later stages.
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