Systemic carnitine deficiency

Definition

Dementia is a loss of mental ability severe enough to interfere with normal activities of daily living, lasting more than six months, not present since birth, and not associated with a loss or alteration of consciousness.

Description

Dementia is a group of symptoms caused by gradual death of brain cells. The loss of cognitive abilities that occurs with dementia leads to impairments in memory, reasoning, planning, and personality. While the overwhelming number of people with dementia are elderly, it is not an inevitable part of aging. Instead, dementia is caused by specific brain diseases. Alzheimer's disease is the most common cause, followed by vascular or multi-infarct dementia.

The prevalence of dementia has been difficult to determine, partly because of differences in definition among different studies, and partly because there is some normal decline in functional ability with age. Dementia affects 5-8% of all people between ages 65 and 74, and up to 20% of those between 75 and 84. Estimates for dementia in those 85 and over range from 30-47%. Between two and four million Americans have Alzheimer's disease; that number is expected to grow to as many as 14 million by the middle of the twenty-first century as the population as a whole ages.

The cost of dementia can be considerable. While most people with dementia are retired and do not suffer income losses from their disease, the cost of care is often enormous. Financial burdens include lost wages for family caregivers, medical supplies and drugs, and home modifications to ensure safety. Nursing home care may cost several thousand dollars a month or more. The psychological cost is not as easily quantifiable but can be even more profound. The person with dementia loses control of many of the essential features of his life and personality, and loved ones lose a family member even as they continue to cope with the burdens of increasing dependence and unpredictability.

Causes & symptoms

Causes

Dementia is usually caused by degeneration of brain cells in the cerebral cortex, the part of the brain responsible for thoughts, memories, actions, and personality. Death of brain cells in this region leads to the cognitive impairment that characterizes dementia.

The most common cause of dementia is Alzheimer's disease (AD), accounting for half to three quarters of all cases. The brain of a person with AD becomes clogged with two abnormal structures, called neurofibrillary tangles and senile plaques. Neurofibrillary tangles are twisted masses of protein fibers inside nerve cells, or neurons. Senile plaques are composed of parts of neurons surrounding a group of proteins called beta-amyloid deposits. Why these structures develop is unknown. Current research indicates possible roles for inflammation, blood flow restriction, and accumulation of aluminum in the brain and toxic molecular fragments known as free radicals or oxidants. Several genes have been associated with higher incidences of AD, although the exact role of these genes is still unknown.

Vascular dementia is estimated to cause from 5-30% of all dementias. It occurs from a decrease in blood flow to the brain, most commonly due to a series of small strokes (multi-infarct dementia). Other cerebrovascular causes include: vasculitis from syphilis, Lyme disease , or systemic lupus erythematosus ; subdural hematoma; and subarachnoid hemorrhage. Because of the usually sudden nature of its cause, the symptoms of vascular dementia tend to begin more abruptly than those of Alzheimer's dementia. Symptoms may progress stepwise with the occurrence of new strokes. Unlike AD, the incidence of vascular dementia is lower after age 75.

Other conditions which may cause dementia include :

• AIDS
• Parkinson's disease
• Lewy body disease
• Pick's disease
• Huntington's disease
• Creutzfeldt-Jakob disease
• brain tumor
• hydrocephalus
• head trauma
• multiple sclerosis
• prolonged abuse of alcohol or other drugs
• vitamin deficiency: thiamin, niacin, or B₁₂
• hypothyroidism
• hypercalcemia

Symptoms

Dementia is marked by a gradual impoverishment of thought and other mental activities. Losses eventually affect virtually every aspect of mental functioning. The slow progression of dementia is in contrast with delirium, which involves some of the same symptoms, but has a very rapid onset and fluctuating course with alteration in the level of consciousness. However, delirium may occur with dementia, especially since the person with dementia is more susceptible to the delirium-inducing effects of may types of drugs.

Symptoms include:

• Memory losses. Short-term memory loss is usually the first symptom noticed. It may begin with misplacing valuables such as a wallet or car keys, then progress to forgetting appointments, where the car was left, and the route home, for instance. More profound losses may eventually follow, such as forgetting the names and faces of family members.
• Impaired abstraction and planning. The person with dementia may lose the ability to perform familiar tasks, to plan activities, and to draw simple conclusions from facts.
• Language and comprehension disturbances. The person may be unable to understand instructions, or follow the logic of moderately complex sentences. Later, he or she may not understand his or her own sentences, and have difficulty forming thoughts into words.
• Poor judgment. The person may not recognize the consequences of his or her actions or be able to evaluate the appropriateness of behavior. Behavior may become ribald, overly-friendly, or aggressive. Personal hygiene may be ignored.
• Impaired orientation ability. The person may not be able to identify the time of day, even from obvious visual clues; or may not recognize his or her location, even if familiar. This disability may stem partly from losses of memory and partly from impaired abstraction.
• Decreased attention and increased restlessness. This may cause the person with dementia to begin an activity and quickly lose interest, and to wander frequently. Wandering may cause significant safety problems, when combined with disorientation and memory losses. The person may begin to cook something on the stove, then become distracted and wander away while it is cooking.
• Personality changes and psychosis. The person may lose interest in once-pleasurable activities, and become more passive, depressed, or anxious. Delusions, suspicion, paranoia, and hallucinations may occur later in the disease. Sleep disturbances may occur, including insomnia and sleep interruptions.

Diagnosis

Since dementia usually progresses slowly, diagnosing it in its early stages can be difficult. Several office visits over several months or more may be needed. Diagnosis begins with a thorough physical exam and complete medical history, usually including comments from family members or caregivers. A family history of either Alzheimer's disease or cerebrovascular disease may provide clues to the cause of symptoms. Simple tests of mental function, including word recall, object naming, and number-symbol matching, are used to track changes in the person's cognitive ability.

Depression is common in the elderly and can be mistaken for dementia; therefore, ruling out depression is an important part of the diagnosis. Distinguishing dementia from the mild normal cognitive decline of advanced age is also critical. The medical history includes a complete listing of drugs being taken, since a number of drugs can cause dementia-like symptoms.

Determining the cause of dementia may require a variety of medical tests, chosen to match the most likely etiology. Cerebrovascular disease, hydrocephalus, and tumors may be diagnosed with x rays, CT or MRI scans, and vascular imaging studies. Blood tests may reveal nutritional or metabolic deficiencies or hormone imbalances.

Treatment

Nutritional supplements

Some nutritional supplements may be helpful, especially if dementia is caused by deficiency of these essential nutrients:

• Acetyl-L-carnitine: improves brain function and increases attention span, enhances ability to concentrate and increases energy in patients with Alzheimer's disease.
• Antioxidants (vitamin E , vitamin C , beta-carotene, or selenium): may slow down disease progression by preventing the damaging effects of free radicals.
• B-complex vitamins and vitamin B12 : may significantly improve mental function in patients who have low levels of these essential nutrients.
• Coenzyme Q10: helps deliver more oxygen to the brain
• DHEA: may increase brain function in old people.
• Magnesium: may be helpful if the dementia is caused by magnesium deficiency and/or accumulation of aluminum in the brain
• Phosphotidylserine: Deficiency of this nutrient may decrease mental function and cause depression.
• Zinc: may boost short-term memory and increase attention span

Herbal treatment

Herbal remedies that may be helpful in treating dementia include Chinese or Korean ginseng, Siberian ginseng, gotu kola , and Ginkgo biloba. Of these, ginkgo biloba is the most well-known and widely accepted by Western medicine. Ginkgo extract, derived from the leaves of the Ginkgo biloba tree, interferes with a circulatory protein called platelet-activating factor. It also increases circulation and oxygenation to the brain. Ginkgo extract has been used for many years in China and is widely prescribed in Europe for treatment of circulatory problems. A 1997 study of patients with dementia appeared to show that gingko extract could improve their symptoms. Some scientists believe that, taken early enough in the process, Ginkgo biloba can delay the onset of Alzheimer's, but this claim has not yet been sufficiently backed by enough supportive studies.

Homeopathy

A homeopathic physician may prescribe patient-specific homeopathic remedies to alleviate symptoms of dementia.

Acupressure

This form of therapy uses hands to apply pressure on specific acupressure points to improve blood circulation and calm the nervous system.

Aromatherapy

Aromatherapists use essential oils as inhalants or in baths to improve mental performances and to calm the nerves.

Chelation therapy

This is a controversial treatment that may provide symptomatic improvement in some patients. However, its effectiveness has not been supported by clinical studies. In addition, this form of therapy may cause kidney damage. Therefore, it should only be given under watchful eyes of a qualified physician.

Allopathic treatment

There are no therapies that can reverse the progression of Alzheimer's disease. Therefore, treatment of dementia begins with treatment of the underlying disease, where possible. Aspirin, estrogen, vitamin E, selegiline, propentofylline and milameline are currently being evaluated for their ability to slow the rate of progression.

Care for a person with dementia can be difficult and complex. The patient must learn to cope with functional and cognitive limitations, while family members or other caregivers assume increasing responsibility for the person's physical needs.

Symptoms of dementia may be treated with a combination of psychotherapy, environmental modifications and medication. Behavioral approaches may be used to reduce the frequency or severity of problem behaviors, such as aggression or socially inappropriate conduct.

Modifying the environment can increase safety and comfort while decreasing agitation. Home modifications for safety include removal or lock-up of hazards such as sharp knives, dangerous chemicals, and tools. Child-proof latches or Dutch doors may be used to limit access as well. Lowering the hot water temperature to 120°F (48.9°C) or less reduces the risk of scalding. Bed rails and bathroom safety rails can be important safety measures, as well. Confusion may be reduced with simpler decorative schemes and presence of familiar objects. Covering or disguising doors (with a mural, for example) may reduce the tendency to wander. Positioning the bed in view of the bathroom can decrease incontinence.

Two drugs, tacrine (Cognex) and donepezil (Aricept), are commonly prescribed for Alzheimer's disease. These drugs inhibit the breakdown of acetylcholine in the brain, prolonging its ability to conduct chemical messages between brain cells. They provide temporary improvement in cognitive functions for about 40% of patients with mild-to-moderate AD. Hydergine is sometimes prescribed as well, though it is of questionable benefit for most patients. Other drugs that are frequently used in dementia patients include antianxiety (for agitation and anxiety) and antipsychotics (for paranoia, delusions or hallucinations) and antidepressants (for depressive symptoms. Evaluation of any medical side effects from the medications should be ongoing.

Long-term institutional care may be needed for the person with dementia, as profound cognitive losses often precede death by a number of years. Early planning for the financial burden of nursing home care is critical. Useful information about financial planning for long-term care is available through the Alzheimer's Association.

Expected results

The prognosis for dementia depends on the underlying disease. On average, people with Alzheimer's disease live eight years past their diagnosis, with a range from one to twenty years. Vascular dementia is usually progressive, with death from stroke, infection, or heart disease .

Prevention

There is no known way to prevent Alzheimer's disease, although several of the drugs under investigation may reduce its risk or slow its progression. Nutritional supplements, including antioxidants, may also help protect against Alzheimer's disease. The risk of developing multi-infarct dementia may be reduced by reducing the risk of stroke. Sources of aluminum, which can be found in aluminum cookware, canned sodas, and certain antacids and deodorants, should be avoided.

Key Terms

Donepezil

A drug commonly prescribed for Alzheimer's disease that provides temporary improvement in cognitive functions for some patients with mild-to-moderate forms of the disease.

Ginkgo extract

Made from the leaves of the tree, this extract, used in other countries to treat circulatory problems, may improve the symptoms of patients with dementia.

Neurofibrillary tangles

Abnormal structures, composed of twisted masses of protein fibers within nerve cells, found in the brains of persons with Alzheimer's disease.

Senile plaques

Abnormal structures, composed of parts of nerve cells surrounding protein deposits, found in the brains of persons with Alzheimer's disease.

Tacrine

A drug commonly prescribed for Alzheimer's disease that provides temporary improvement in cognitive functions for some patients with mild-to-moderate forms of the disease.

Further Reading

For Your Information

Books

• Halpern, Georges. Ginkgo: A Practical Guide. Garden City Park, NY: Avery Publishing Group, 1998.
• Jacques, Alan. Understanding Dementia. New York: Churchill Livingstone, 1992.
• Mace, Nancy L. and Peter V. Rabins. The 36-Hour Day. Baltimore: Johns Hopkins University Press, 1995.
• Murray, Michael and Joseph Pizzorno. "Alzheimer's Disease." In Encyclopedia of Natural Medicine. 2nd ed. Rocklin, CA: Prima Publishing, 1998.
• Zand, Janet, Allan N. Spreen, and James B. LaValle. "Alzheimer's Disease." In Smart Medicine for Healthier Living: A Practical A-to-Z Reference to Natural and Conventional Treatments for Adults. Garden City Park, NY: Avery Publishing Group, 2000.

Organization

• Alzheimer's Association. 919 North Michigan Ave., Suite 1000, Chicago, IL 60611. (800) 272-3900 (TDD: (312) 335-8882). http://www.alz.org/.

Gale Encyclopedia of Alternative Medicine. Gale Group, 2001.