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What
are the Elements of Nonpharmacologic Treatment of Dementia?
In
most instances, dementia is due to Alzheimer's or Multiple infarcts.
In these patients, treatment is palliative rather than curative.
However, over 30% of patients with dementia have more than one illness
contributing to the dementia state. Treatment of these concomitant
disorders provides temporary improvement in 28% of 200 patients
and improvement is sustained for at least one year in 14%. Thus
patients with irreversible dementia due to Alzheimer's and MID may
improve in function with comprehensive management, although their
cognitive status continues to inexorably deteriorate. In the case
of Alzheimer's Disease, practitioners should assist the patient's
family in providing a supportive environment to compensate for the
patient's disabilities, minimize the cognitive side effects of medications,
and maximize function of organs other than the brain by treating
concomitant illnesses. Maintenance of nutrition, and exercise are
vital, as is social stimulation. Additionally, one must assist and
counsel caregivers, by providing respite when needed as well as
consultation on the legal and ethical issues that arise over the
course of dementia.
Family
and caregiver counseling is a critical component of he management
of the demented patient. Families must be advised of the community
support services and day care centers and other forms of respite.
To avoid crises, families should be given advance notice of potential
legal and ethical issues that arise over the course of dementia.
Therefore, issues of durable power of attorney and other forms of
advance directives should be discussed early in the illness. One
of the difficult but predictable issues for families is whether
to use artifical feeding when the demented patient progresses to
the point that oral intake is insufficient or unsafe because of
aspiration. The physician should try to get the caregivers to decide
whether artifical feeding will be used before a decision has to
be made.
What
Drugs are Useful in Treating Dementia?
Drug
useful in treatment of dementia fall in to two categories: drugs
aimed at managing behavioral problems, such as combativeness, agitation
and sleeplessness; and drugs aimed at improving cognition. A review
of controlled trial of neuroleptic treatment in dementia showed
that 18% of dementia patients benefited but only modestly. No single
neuroleptic is superior. Although there is little scientific evidence
for the widespread use of these agents, neuroleptics are superior
to placebo in controlling anxiety, suspiciousness, uncooperativenes
and hallucinatory behaviors. It is safest to use these drugs only
if signs and symptoms of psychosis or significant excitement and
agitation complicate management. On the contrary, repetitive behaviors
such as aimless wandering, pacing and calling out are usually less
responsive to neuroleptics and they have little effect on poor self
care, social withdrawal, wandering and cognition. In these instances,
the adverse effects of neuroleptics (sedation, orthostatis, Parkinsonism,
falls and urinary retention) may reduce functional status outweighing
any benefit. When antipsychotic agents are used, butyrophenones
or other high potency agents rather than the more sedating phenothiazine
agents are indicated. The latter may be preferable if sedation is
needed. Other psychotropics including benzodiazepines, betablockers
and the antidepressant, trazodone, have been used also to induce
sleep and control agitation. In summary, agents for behavioral control
should be used as a last resort. When used, the practitioner should
avoid combining more than of these agents concurrently.
Drugs
aimed at altering the progressive cognitive decline in dementia
have been the subject of multiple clinical trials. In multi-infarct
dementia (MID), the principal aim is to prevent further brain infarcts
by use of aspirin and antihypertensives, though data to support
efficacy are lacking. Vasodilators in MID have shown little benefit.
Recently attention has been directed at developing effective therapy
for Alzheimer's Disease. Categories of medications proposed to treatment
Alzheimer's include cholinomimetics to restore deficiencies of acetyl
choline in the brain; neuropeptides to induce cortical interneuronal
transmission, nootropic agents to stimulate neuron metabolic activity;
vascular agents to improve blood flow; calcium blockers to prevent
the accumulation of calcium in injured neurons; and miscellaneous
agents including nerve growth factors and cell membrane stabilizers.
What
is the Benefit of Acetylcholine Esterase Inhibitors?
For
clinical use, most progress in the treatment of Alzheimer's Disease
has been made with acetylcholine esterase inhibitors. Tetrahydroaminoacridine
(Tacrine), recently released in the United States, has been marketed
for patients with mild to moderate disease. Recent randomized trials
of tacrine in England, Canada, and the United States provide a basis
for using this medication in some patients. Of note, patients studied
have had mild to moderate dementia (mean Mini-Mental State Examination
score of 16 to 18). When seen, improvements have been in cognitive
rather than in behavioral function. In summary, studies show that
tacrine in doses of 40 to 160 mg per day :
- benefits
a small subgroup of patients with Alzheimer's Disease;
- improves
cognition or slows rate of cognitive decline over a short period,
but the magnitude of the improvement is small ;
- commonly
causes hepatotoxicity that is usually reversible; and most important,
- clinical
use requires a clear commitment from patients, caregivers, and
clinicians because of the need for careful monitoring.
On
the other hand, the duration of the effect of Tacrine is unknown
since studies have been of short duration and because study populations
have been highly selected, its effectiveness in severe dementia
or in demented patients with co-morbidities is unknown.
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