Health Encyclopedia - Diseases and Conditions

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Alzheimer's Disease

• Definition of Alzheimer's Disease
• Description of Alzheimer's Disease
• Causes and Risk Factors of Alzheimer's Disease
• Symptoms of Alzheimer's Disease
• Diagnosis of Alzheimer's Disease
• Treatment of Alzheimer's Disease
• What Questions To Ask Your Doctor About Alzheimer's Disease
• Self Care Alzheimer's Disease

Definition of Alzheimer's Disease

Alzheimer's disease is a group disorders involving the parts of the brain that control thought, memory, and language. It is marked by progressive deterioration, which affects both the memory and reasoning capabilities of an individual.

Description of Alzheimer's Disease

Alzheimer's disease is the most common form of dementia (mental deterioration of memory and thought processes) among the elderly. It is estimated that 4.5 million Americans over the age of 65 are affected with this condition. After the age of 65, the incidence of the disease doubles every five (5) years and, by age 85, it will affect nearly half of the population.

Alzheimer's disease was first described in 1906 by German neurologist Alois Alzheimer. The disease causes irreversible changes in the nerve cells of certain vulnerable areas of the brain. It is characterized by nerve-cell loss, abnormal tangles within nerve cells and deficiencies of several chemicals, which are essential for the transmission of nerve messages.

The disorder leads to behavioral and personality changes, forgetfulness, confusion, inability to learn new material, paranoia and motor activity problems. Language difficulties also are common in people with Alzheimer's disease. The disease typically progresses to the stage where it is difficult for the patient to be understood by others or to understand others, and in the final stages, the patient is bedridden.

Although nearly half of those over 85 may have Alzheimer's disease, it is not a 'normal' part of aging.

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Causes and Risk Factors of Alzheimer's Disease

The cause of Alzheimer's disease has yet to be determined, but there are five (5) theories that warrant further investigation:

1. Chemical Theories

   A. Chemical Deficiencies. One of the ways in which brain cells communicate with one another is through chemicals called neurotransmitters. Studies of Alzheimer's diseased brains have uncovered diminished levels of various neurotransmitters that are thought to influence intellectual functioning and behavior.

   B. Toxic Chemical Excesses. Increased deposits of aluminum have been found in Alzheimer's disease brains.

2. Genetic Theory.

   Researchers have linked late-onset Alzheimer's to the inheritance of a gene that directs production of apolipoprotein (ApoE). In early-onset Alzheimer's, researchers identified a mutation on chromosome 14, which accounts for 10 percent of Alzheimer's cases. Additionally, a mutation was found on chromosomes 1 and 21. In 1997, researchers found another mutation on chromosome 12 that is linked to late-onset Alzheimer's.

3. Autoimmune Theory.

   The body's immune system, which protects against potentially harmful invaders, may erroneously begin to attack its own tissues, producing antibodies to its own essential cells.

4. Slow Virus Theory.

   A slow-acting virus has been identified as a cause of some brain disorders that closely resemble Alzheimer's.

5. Blood Vessel Theory.

   Defects in blood vessels supplying blood to the brain are being studied as a possible cause of Alzheimer's.

The chances of getting Alzheimer's disease increases with age and it usually occurs after the age of 65, after which the chances of getting the disease double every five years.

There are only two definite factors that increase the risk for Alzheimer's disease before age 65: a family history of dementia or Alzheimer's, and Down syndrome. Down syndrome is a combination of physical abnormalities and mental retardation characterized by a genetic defect in chromosome pair 21.

Symptoms of Alzheimer's Disease

The U.S. Agency for Health Care Policy Research provided this list of questions to help recognize the condition:

• Learning and retaining new information. Does the person misplace objects and/or have trouble remembering appointments or recent conversations? Is the person repetitive in conversation?
• Handling complex tasks. Do familiar activities like balancing a checkbook, cooking a meal, or other tasks that involve a complex train of thought, become increasingly difficult?
• Ability to reason. Does the person find it difficult to respond appropriately to everyday problems, such as a flat tire? Does a previously well-adjusted person disregard rules of social conduct?
• Spatial ability and orientation. Does driving and finding one's way in familiar surroundings become impossible? Does the person have problems recognizing familiar objects?
• Language. Does the person have difficulty following or participating in conversations? Does the person have trouble finding the words to express what they want to say?
• Behavior. Does the person seem more passive or less responsive than usual or more suspicious or irritable? Does the person have trouble paying attention?

The onset and symptoms of Alzheimer's disease are usually very slow and gradual, seldom occurring before the age of 65. It occurs in the following three (3) stages:

Diagnosis of Alzheimer's Disease

An estimated 5 to 10 percent of all mental deterioration in persons over the age of 65 is due to reversible conditions, such as depression, underlying physical disease (metabolic disorders, cardiovascular disease or pernicious anemia), excessive and inappropriate drug use, loss of social support or change in social environment. Therefore, it is important to diagnose Alzheimer's disease to ensure that any mental impairment is not reversible.

In order to diagnose Alzheimer's disease, a physician must:

• take a detailed medical history
• conduct physical and neurological examinations
• consult the diagnostic criteria stated below
• conduct laboratory examinations, such as urine tests, a CAT scan, magnetic resonance imaging (MRI) or positron emission tomography (PET) to detect structural abnormalities of the head and brain
• conduct a functional and mental status assessment test
• do a complete inventory of any prescription and over-the-counter drugs the patient is taking

The diagnostic criteria for dementia and Alzheimer's disease is as follows:

Dementia

A. Multiple cognitive deficits manifested by both 1 and 2

1. Impaired short- or long-term memory
2. One or more of the following cognitive disturbances:

• Impaired language ability
• Impaired ability to carry out motor activities
• Impaired ability to recognize objects
• Impaired abstract thinking (e.g., planning and organizing)

B. Deficits in A are sufficient to interfere with work or social activities and represent a significant decline in function.

C. Deficits do not occur exclusively during the course of delirium.

Alzheimer's disease

Dementia as determined by A through C (stated above), plus:

D. Disease course is characterized by gradual onset and continuing cognitive decline.

E. Cognitive deficits are not caused by any of the following:

• Another progressive central nervous system disorder (e.g., Parkinson's or Huntington's disease)
• A systemic condition (e.g., hypothyroidism or niacin deficiency)
• A substance-induced condition

F. Disturbance is not better explained by another disorder (e.g., major depressive disorder or schizophrenia).

Treatment of Alzheimer's Disease

Although there is currently no cure for Alzheimer's disease, a great deal can be done to manage it. There are four (4) approaches to managing the disease. The approaches and solutions are:

• Relieve behavioral symptoms associated with dementia, including depression, agitation and psychosis. Medications, called cholinesterase inhibitors, such as tacrine (Cognex), donepezil (Aricept), rivastigmine (Exelon) or galantamine (Reminyl), enhance the effectiveness of acetylcholine (the chemical messenger found in the neurotransmitter system which coordinates memory and learning) by slowing its breakdown. Unfortunately, these medications only temporally improve the symptoms associated with Alzheimer's. The effects of the drugs will fade as the deterioration of brain cells progresses. More recently, memantine (Namenda) was approved by the FDA. Memantine blocks the effects of a different chemical, glutamate, which is felt to overstimulate nerve cells and cause their degeneration. Additionally, doctors may prescribe antidepressants, antipsychotics, anticonvulsants, beta blockers, benzodiazepines, serotonin reuptake inhibitors, and drugs such as Desyrel, BuSpar, and Eldepryl, to control the agitation, psychosis, depressive features, anxious features, apathy and disturbances in sleep and appetite.
• Relieve cognitive dysfunction to improve memory, language, attention and orientation. Doctors may prescribe precursors, cholinesterase inhibitors and cholinergic receptor agents.
• Slow the rate of illness progression, thereby preserving quality of life and independence.
• Delay the time of onset of illness. Medications and therapies to combat these problems are still in the development and clinical trial stages. For instance, the research shows that vitamin E slows the progress of some consequences of Alzheimer’s for about 7 months, and scientists are investigating whether ginkgo biloba can delay or prevent dementia in older people, and if estrogen can prevent Aalzheimer’s in women with a family history of the disease. Researchers are looking at methods to enhance cerebral metabolism, stabilize membranes, promote neuronal sprouting, decrease inflammation, neurotoxins and excitatory amino acids, as well as alter metabolism of key proteins.

In addition to the pharmaceutical approaches, conservation methods also can be beneficial to the management of Alzheimer's disease, such as:

• eating a proper diet
• getting daily exercise
• continuing intellectual stimulation and social contact
• implementing memory aids, such as a prominent calendar, lists of daily tasks and labels on frequently used items that can help compensate for memory loss and confusion
• providing a comfortable and stimulating environment and always trying to give simple and easy to understand instructions
• participating in support groups

What Questions To Ask Your Doctor About Alzheimer's Disease

What tests need to be done to accurately diagnose this condition?

Does the individual have Alzheimer's or could it be some other condition or disorder?

Can it be cured? Must it necessarily become progressively worse or can deterioration be halted?

Can mental or thinking abilities be improved? Can motor activities be improved?

Is there a special diet that may help?

How can the family get help to cope with this disease?

Self Care Alzheimer's Disease

The physical, emotional and financial burdens of caring for a person with Alzheimer's disease can be enormous. Family members and other caregivers may become exhausted and demoralized by the all-consuming task. They lose freedom and privacy and sacrifice their own needs, often without receiving much gratitude or even acknowledgment. Any resentment they feel may be heightened by fear of inheriting the disease and compounded by guilt - about their anger, past mistakes, lying to the patient in small ways or denying the patient's wishes.

Existing family problems may be intensified and old family conflicts revived. A formerly passive husband or wife may find it difficult to make decisions for the patient. It is not surprising that caregivers have a higher rate of depression than patients with Alzheimer's disease themselves.

Some caregivers join support groups to relieve their isolation, comfort one another and exchange advice. These groups are organized by local chapters of the Alzheimer's Association (http://www.alz.org).

Most of all, caregivers need time to lead their own lives. This can be made possible by respite care: housekeepers, home attendants, visiting nurses, day care centers, senior citizen programs, day hospitals and case managers who can coordinate services. Unfortunately, many families know too little about these services or are too shy or proud to seek help.

At any given time, family members care for most people with Alzheimer's disease, but the demands eventually become too great for even the most devoted wife, daughter, husband or son. Most Americans with this disease ultimately end up in nursing homes. Researchers have recently estimated that 40 percent of people who turn 65 will eventually enter a nursing home; 25 percent will stay for at least a year and nearly 10 percent for five years or more. The average age of the 1.5 million patients in these homes is 86. More than two-thirds of these patients are women, and at least two-thirds have Alzheimer's disease.

About two-thirds of all people placed in nursing homes die within three years, mainly because many families take this step only after their resources are exhausted and the demented person is near death. Families sometimes wait too long and have to be persuaded by outsiders to acknowledge the need. To avoid having to make a hasty decision during a crisis, it is better to start investigating the options as soon as the patient begins to need supervision.