THE DEMENTIAS: MULTI-INFARCT DEMENTIA AND ALZHEIMER’S DISEASE
Dementia reportedly affects 3% to 11% of community-residingadults older than 65 years of age and 20% to 50% of community-residing adults older than age 85. Most of those suffering from dementia who are in the over-85 age group reside in institutional settings. Of those individuals 100 years and older, almost 60% are noted to demonstrate dementia. Despite this high incidence, clinicians fail to detect dementia in 21% to 72% of patients. In order for a diagnosis of dementia to be made, at least two domains of altered function must exist—memory and at least one of the following: language, perception, visuospatial function, calcula-tion, judgment, abstraction, and problem-solving (Mayo Foun-dation for Medical Education and Research [Mayo], 2001).
Symptoms are usually subtle in onset and often progress slowly until they are obvious and devastating. The changes char-acteristic of dementia fall into three general categories: cognitive, functional, and behavioral. Reversible causes of dementia include alcohol abuse, medication use (polypharmacy), psychiatric disor-ders, and normal-pressure hydrocephalus. The three most com-mon nonreversible dementias are Alzheimer’s disease, multi-infarct dementia, and mixed Alzheimer’s and multi-infarct dementia. Alzheimer’s disease accounts for more than 60% of all dementias, and multi-infarct dementia (vascular dementia) accounts for another 5% to 20%. Other non-Alzheimer’s dementias include Parkinson’s disease, AIDS-related dementia, and Pick’s disease. These remaining dementias account for fewer than 15% of cases and are relatively uncommon (National Institute of Neurologi-cal Disorders and Stroke, 2000).
Dementia is characterized by an uneven, downward decline in mental function. Multi-infarct dementia is sometimes confused with Alzheimer’s disease, paranoia, or delirium because of its un-predictable clinical course. The diagnosis can be even more diffi-cult if the patient is suffering from both Alzheimer’s disease and multi-infarct dementia.
Multi-infarct, or vascular dementia, has the following defin-ing characteristics:
· There must be evidence of dementia.
· There must be evidence of cerebrovascular disease (by his-tory, clinical examination, or brain imaging).
· The two disorders must be reasonably related.
Alzheimer’s disease is a progressive, irreversible, degenerative neurologic disease that begins insidiously and is characterized by gradual losses of cognitive function and disturbances in be-havior and affect. Alzheimer’s disease is not found exclusively in the elderly; in 1% to 10% of cases, its onset occurs in middle age. A family history of Alzheimer’s disease and the presence of Down syndrome are two established risk factors for Alzheimer’s disease. If family members have at least one other relative with Alzheimer’s disease, then a familial component, which non specifically includes both environmental triggers and genetic determinants, is said to exist. Genetic studies show that autosomal-dominant forms of Alzheimer’s disease are associated with early onset and early death.
In 1987, chromosome 21 was first implicated in early-onset fa-milial Alzheimer’s disease. Soon after, the gene coding for amyloid precursor protein (APP) was also found to be on chromosome 21. Not until 1991 was an actual mutation in association with famil-ial Alzheimer’s disease found in the APP gene of chromosome 21. For those with this gene, onset of Alzheimer’s disease began in their 50s. Only a few of the cases of familial Alzheimer’s disease have been found to involve this genetic mutation. In 1992, chromosome 14 was found to contain an unidentified mutation also linked to familial Alzheimer’s disease. Since 1995, molecular biologists have been discovering even more-specific genetic information about the various forms of Alzheimer’s disease, including genetic differences between early- and late-onset Alzheimer’s disease. These genetic differences are helping to pinpoint risk factors associated with the disease, although the genetic indicators are not specific enough to be used as reliable diagnostic markers (Mayo, 2001).
Specific neuropathologic and biochemical changes are found in patients with Alzheimer’s disease. These include neurofibrillary tangles (a tangled mass of nonfunctioning neurons) and senile or neuritic plaques (deposits of amyloid protein, part of a larger pro-tein, APP) in the brain. This neuronal damage occurs primarily in the cerebral cortex and results in decreased brain size. Similar changes are found to a lesser extent in the normal brain tissue of older adults. Cells that use the neurotransmitter acetylcholine are the ones principally affected by this disease. Biochemically, the enzyme active in producing acetylcholine, which is specifically involved in memory processing, is decreased.
Several theories are currently being tested to explain what pre-disposes an individual to develop the plaques and neurotangles that can be seen at autopsy on biopsy of the brains of Alzheimer’s pa-tients (Mayo, 2001). Scientists continue to increase their under-standing of the complex ways in which aging and genetic and nongenetic factors affect and damage brain cells over time and eventually lead to Alzheimer’s disease. Researchers have recently discovered how and why amyloid plaques form and cause neuronal death, as well as the possible relationship between various forms of tau protein and impaired function, which leads to neuronal death. The major role of tau protein is to regulate the assembly and sta-bility of neurons. Researchers are also beginning to discover the roles of inflammation and oxidative stress and the contribution of brain infarctions to the disease (Alzheimer’s Disease Education and Referral Center, 1999).
In the early stages of Alzheimer’s disease, forgetfulness and subtle memory loss occur. The patient may experience small difficulties in work or social activities but has adequate cognitive function to hide the loss and can function independently. Depression may occur at this time. With further progression of the disease, the deficits can no longer be concealed. Forgetfulness is manifested in many daily actions. These patients may lose their ability to recog-nize familiar faces, places, and objects and may get lost in a famil-iar environment. They may repeat the same stories because they forget that they have already told them. Trying to reason with theperson and using reality orientation only increase the patient’s anxiety without increasing function. Conversation becomes diffi-cult, and there are word-finding difficulties. The ability to formu-late concepts and think abstractly disappears; for instance, the patient can interpret a proverb only in concrete terms. The patient is often unable to recognize the consequences of his or her actions and will therefore exhibit impulsive behavior. For example, on a hot day, the patient may decide to wade in the city fountain fully clothed. The patient has difficulty with everyday activities, such as operating simple appliances and handling money.
Personality changes are also usually evident. The patient may become depressed, suspicious, paranoid, hostile, and even com-bative. Progression of the disease intensifies the symptoms: speak-ing skills deteriorate to nonsense syllables, agitation and physical activity increase, and the patient may wander at night. Eventu-ally, assistance is needed for most ADLs, including eating and toi-leting, since dysphagia occurs and incontinence develops. The terminal stage, in which the patient is usually immobile and re-quires total care, may last for months or years. Occasionally, the patient may recognize family or caretakers. Death occurs as a result of complications such as pneumonia, malnutrition, or dehydration.
The health history, including medical history; family history; so-cial and cultural history; medication history, and the physical ex-amination, including functional and mental health status, are key in the diagnosis of probable Alzheimer’s disease. Diagnostic tests, including complete blood count, the Venereal Disease Research Laboratory (VDRL) test for syphilis, HIV testing, chemistry pro-file, and vitamin B12 and thyroid hormone levels, as well as screen-ing with electroencephalography (EEG), computed tomography (CT), magnetic resonance imaging (MRI), and examination of the cerebrospinal fluid may all refute or support a diagnosis of probable Alzheimer’s disease.
Depression can closely mimic early-stage Alzheimer’s disease and coexists in many patients. A depression scale is helpful in screening for underlying depression. Tests for cognitive func-tion, such as the Mini-Mental State Examination (see Chart 12-3) and the clock-drawing test, are useful for screening. CT and MRI scans of the brain are useful for excluding hematoma, brain tumor, stroke, normal-pressure hydrocephalus, and atrophy but are not reliable in making a definitive diagnosis of Alzheimer’s disease. Infections, physiologic disturbances such as hypothy-roidism, Parkinson’s disease, and vitamin B12 deficiency can produce cognitive impairment that may be misdiagnosed as Alzheimer’s disease. Biochemical abnormalities can be excluded through examination of the blood and cerebrospinal fluid, but the findings are not specific enough to make the diagnosis. A di-agnosis of “probable Alzheimer’s disease” is made when the med-ical history, physical examination, and laboratory tests have excluded all known causes of other dementias. The diagnosis can be confirmed only by cerebral biopsy (Mayo, 2001).
In the fall of 1993, the U.S. Food and Drug Administration ap-proved the first medication for treatment of the symptoms of Alzheimer’s disease, tacrine hydrochloride (Cognex). This agent enhances acetylcholine uptake in the brain, thus maintaining mem-ory skills for a period of time. Because this medication can cause liver toxicity, patients must be closely monitored. It was not until early 1997 that donepezil (Aricept), a second medication in this cat-egory of acetylcholinesterase inhibitors, was introduced. In 2000, a third medication in this class, rivastigmine (Exelon) was introduced in the United States after completion of research trials conducted in more than 70 countries. These two newer preparations have far fewer side effects, although they continue to require ongoing mon-itoring. They vary in their level of effectiveness from patient to pa-tient, due in part to their window of effectiveness, which in general is limited to the early stages of dementia (Fillit, 2000).
Although Alzheimer’s disease is the focus of this nursing manage-ment discussion, the interventions described apply to all patients with dementia, regardless of the cause. Nursing interventions are aimed at maintaining the patient’s physical safety; reducing anxi-ety and agitation; improving communication; promoting inde-pendence in self-care activities; providing for the patient’s needs for socialization, self-esteem, and intimacy; maintaining adequate nu-trition; managing sleep pattern disturbances; and supporting and educating family caregivers. Research has demonstrated that when the nurse can provide such support, older adults are able to main-tain higher levels of perceived and actual health (Forbes, 2001).
As the patient’s cognitive ability declines, the nurse provides a calm, predictable environment that helps the person interpret his or her surroundings and activities. Environmental stimuli are limited, and a regular routine is followed. A quiet, pleasant man-ner of speaking, clear and simple explanations, and use of mem-ory aids and cues help to minimize confusion and disorientation and give the patient a sense of security. Prominently displayed clocks and calendars may enhance orientation to time. Color-coding the doorway may help the patient who has difficulty lo-cating his or her room. Active participation may help the patient to maintain cognitive, functional, and social interaction abilities for a longer period. Physical activity and communication have also been demonstrated to slow some of the cognitive decline of Alzheimer’s disease (Nursing Research Profile 12-1).
A safe environment allows the patient to move about as freely as possible and relieves the family of constant worry about safety.
To prevent falls and other injuries, all obvious hazards are re-moved. Nightlights are helpful. The patient’s intake of medica-tions and food is monitored. Smoking is allowed only with supervision. A hazard-free environment allows the patient maxi-mum independence and a sense of autonomy. Because of a short attention span and forgetfulness, wandering behavior can often be reduced by gently persuading or distracting the patient. Re-straints are avoided because they may increase agitation. Doors leading from the house must be secured. Outside the home, all activities must be supervised to protect the patient, and the pa-tient should wear an identification bracelet or neck chain in case he or she becomes separated from the caregiver.
Despite profound cognitive losses, the patient will, at times, be aware of his or her rapidly diminishing abilities. The patient will need constant emotional support that reinforces a positive self-image. When losses of skills occur, goals are adjusted to fit the pa-tient’s declining ability.
The environment should be kept uncluttered, familiar, and noise free. Excitement and confusion can be upsetting and may precipitate a combative, agitated state known as a catastrophic re-action (overreaction to excessive stimulation). During such a re-action, the patient responds by screaming, crying, or becoming abusive (physically or verbally). This may be the patient’s only way of expressing an inability to cope with the environment. When this occurs, it is important to remain calm and unhurried. Measures such as listening to music, stroking, rocking, or dis-traction may quiet the patient. Frequently, the patient forgets what triggered the reaction. Structuring of activities is also help-ful. Becoming familiar with the patient’s predicted responses to certain stressors helps caregivers to avoid similar situations.
By the time most older persons with dementia have progressed to the late stages of the disease, they typically reside in nursing homes and are predominantly cared for by nurses’ aides. De-mentia education for caregivers is imperative to minimize patient agitation and is very effectively taught by advanced practice nurse specialists (Nursing Research Profile 12-2).
To promote the patient’s interpretation of messages, the nurse re-mains unhurried and reduces noises and distractions. The nurse uses clear, easy-to-understand sentences to convey messages, be-cause the patient frequently forgets the meaning of words or has difficulty organizing and expressing thoughts. Lists and simple written instructions can serve as reminders to the patient and are often helpful. Sometimes, the patient can point to an object or use nonverbal language to communicate. Tactile stimuli, such as a hug or a hand pat, are usually interpreted as signs of affection, concern, and security.
Pathophysiologic changes in the brain make it difficult for a per-son with Alzheimer’s disease to maintain physical independence. The nurse should help the person remain functionally indepen-dent for as long as possible. One way to do this is to simplify daily activities by organizing them into short, achievable steps so that the patient experiences a sense of accomplishment. Frequently, an occupational therapist can suggest ways to simplify tasks or recommend adaptive equipment. Direct patient supervision is sometimes necessary, but maintaining personal dignity and au-tonomy is important for the person with Alzheimer’s disease. He or she is encouraged to make choices when appropriate and to participate in self-care activities as much as possible.
Because socialization with old friends can be comforting, visits, let-ters, and phone calls are encouraged. Visits should be brief and nonstressful; limiting visitors to one or two at a time helps to re-duce overstimulation. Because recreation is important, the person is encouraged to enjoy simple activities. Realistic goals that provide satisfaction are appropriate. Hobbies and activities such as walking, exercising, and socializing can improve the quality of life. The non-judgmental friendliness of a pet may provide a lonely person with stimulation, comfort, and contentment. Care of the pet by the pa-tient can also provide a satisfying activity and an outlet for energy.
Alzheimer’s disease does not eliminate the need for intimacy. The patient and his or her spouse may or may not continue to enjoy sexual activity. The spouse should be encouraged to talk about any sexual concerns, and sexual counseling may be sug-gested if necessary. Simple expressions of love, such as touching and holding, are often meaningful.
Mealtime can be a pleasant, social occasion or a time of upset and distress, so it should be kept simple and calm, without confrontations. The patient will prefer familiar foods that look appetizing and taste good. To avoid the patient’s “playing” with the food, one dish is offered at a time. Food is cut into small pieces to prevent choking. Liquids may be easier to swallow if they are converted to gelatin. Hot food and beverages are served warm, but the temper-ature of the foods should be checked to prevent burns.
When lack of coordination interferes with self-feeding, adap-tive equipment is helpful. Some patients may do well eating with their fingers. If this is the case, an apron or a smock, rather than a bib, is used to protect clothing. As deficits progress, it may be necessary to feed the patient. Forgetfulness, disinterest, dental problems, incoordination, overstimulation, and choking can all serve as barriers to good nutrition.
Many patients with Alzheimer’s disease exhibit sleep distur-bances, wandering, and behaviors that may be deemed inappro-priate. These behaviors are most likely to occur when there are underlying physical or psychological needs that are unmet. It is imperative that caregivers seek to learn the needs of the patient who is exhibiting this type of behavior, because further health decline can ensue if the source of the problem is not corrected. Adequate sleep and physical exercise are essential. If sleep is interrupted or the patient is unable to fall asleep, music, warm milk, or a back rub may help the person relax. During the day, the patient should be given sufficient opportunity to participate in exercise activities, because a regular pattern of activity and rest will enhance nighttime sleep. Long periods of daytime sleeping are discouraged.
The emotional burden placed on the family of a patient with Alzheimer’s disease is enormous. The physical health of the pa-tient is often very stable, and the mental degeneration is gradual. Because the diagnosis is not specific, the family may cling to the hope that the diagnosis is incorrect and that the person will im-prove if he or she tries harder. Aggression and hostility exhibited by the patient are often misunderstood by the caregiver or fam-ily, who feel unappreciated, frustrated, and angry. Feelings of guilt, nervousness, and worry contribute to caregiver fatigue, de-pression, and family dysfunction. In some cases caregivers them-selves can become so fatigued as a result of the stress of caregiving that elder neglect or abuse can occur. This has been documented in home situations as well as institutions. If elder neglect or abuse of any kind—including physical, psychological, sexual, or finan-cial abuse—is suspected, the local adult protective services agency must be notified; the role of the nurse is not to prove the neglect or abuse, but to report it (Tumolo, 2000).
The multiple needs of family caregivers have been addressed by the Alzheimer’s Association. This national organization is a coalition of family members and professionals who share the goals of family support and service, education, research, and advocacy. Family support groups, respite care, and adult day care are avail-able through the Alzheimer’s Association. Concerned volun-teers are trained to provide structure to caregiver support groups. Through the use of respite care, a service commonly provided, the caregiver can get away from the home for short periods while someone else is tending to the patient’s needs.
The nurse must be sensitive to the highly emotional issues that the family is confronting. Support and education of the caregivers are essential components of care. The family can contact the Alzheimer’s Association or a comparable group that provides the opportunity to meet with others who are experiencing similar problems.
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