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Perspectives for Better Neurological Care
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C. Robert Adams, M.D.
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Board
Certified Neurologist
109 N. 15th St., Ste 14, Norfolk Ne. 68701 Phone: 402-371-0226
Toll Free: 888-516-2398
Parkinson’s Disease
(Extrapyramidal Syndromes)
- Clinical diagnosis.
- Parkinson’s disease is a clinical diagnosis made by
observation of the patient. There is no blood test nor x-ray image that can
delineate the diagnosis of Parkinson’s disease. Some combination of the
following would lead to diagnosis of Parkinson’s disease or an
extrapyramidal syndrome.
i.
Tremor (shaking).
ii.
Stiffness.
iii.
Slowness (bradykinesia).
iv.
Weakness (fatigue).
v.
Difficulty walking (postural imbalance).
- Other associated signs and symptoms can include:
i.
Dysarthria.
ii.
Drooling.
iii.
Micrographia.
iv.
Orthostatic dizziness.
v.
Loss of sense of smell.
vi.
Seborrheic dermatitis.
- Primary Parkinson’s disease is not associated with any
identifiable cause. It could be idiopathic (probably degenerative),
inherited, or one of the “degenerative plus” syndromes.
- Secondary Parkinson’s disease is extremely common and
can be related to:
- Psychotropic medications (major tranquilizers).
- Head trauma.
- Multi-infarct syndrome (strokes).
- Wilson’s disease.
- Hyperparathyroidism.
- Poisons (carbon monoxide, other chemicals, including
some found in the process of illicit drug use).
- Hydrocephalus.
- Hypoxic brain injury as with cardiac arrest.
- Huntington’s disease.
- Hereditary or familial Parkinson’s disease is not
common but is sometimes seen. The inheritance may have variable penetrance
and severity of manifestations.
- Secondary Parkinson’s disease often does not respond
as well as to drugs as compared to primary or idiopathic Parkinson’s
disease. An exception to this rule is Parkinson’s disease related to
psychotropic medications.
- Initial treatment priorities should be first addressed
to general medical conditions pertinent to functioning, overall health, well
being, and longevity:
- Hypertension.
- Diabetes.
- Thyroid dysfunction.
- Hyperlipidemia.
- Vascular disease affecting the brain and heart.
- Vitamin deficiencies.
- Arthritis.
- Others.
- Secondary considerations include assurance of management
of other nonspecific complaints such as:
- Constipation.
- Heartburn.
- Anxiety.
- Depression.
- Sexual dysfunction.
- In sum. It is important not to be one dimensional in
consideration and treatment of Parkinson’s disease. A neurology specialist
needs to work in conjunction with the primary doctor in providing holistic
care.
- The specific treatment of Parkinson’s disease involves
trying to decrease the aforementioned symptoms of:
- Tremor.
- Stiffness.
- Slowness.
- Weakness.
- Postural imbalance.
- Medications may include:
- Carbidopa/levodopa combination (Sinemet) has been the
primary mainstay of treatment for Parkinson’s disease. This drug
combination can help all the above-mentioned five problems to a certain
extent, although often some more than others.
- In relative terms, the carbidopa/levodopa combination
will “loosen up” a patient and help them be more athletic, brisk, and
comfortable in their movements.
- Worries and observations with regards to use of the
Sinemet requires some reassurance, and these include:
- The early institution of treatment with Sinemet does
not adversely affect the long-term outcome of Parkinson’s disease.
- The early and long-term use of Sinemet is not going to
adversely affect the brain or cause the brain to deteriorate.
- Sensitivity and benefit from Sinemet can initially be
quite striking. Sometimes the effect can then start to wear off, and
increasing doses and more frequent administration of the Sinemet becomes
required.
- Unfortunately, the course of Parkinson’s disease tends
to be an insidiously worsening or declining process. Many patients can have
very low grade indolent symptoms very responsive to Sinemet for many years.
Some patients can show a more rapid decline and then a resistance to the
Sinemet.
- Dyskinesia, dystonia, and akathisia can all be side
effects of the use of Sinemet and other dopamine agonists. These are
abnormal involuntary movements, which occur as a consequence of the dopamine
stimulation with the Sinemet. Examples include facial grimacing and
“restlessness.” Unfortunately, abnormal movements, dyskinesia, etc. can
occur while the Parkinsonian symptoms of tremor, stiffness, etc., seem to be
relatively undertreated. A patient can, relatively speaking, be
undermedicated and at the same time be “poisoned” or toxic from the Sinemet.
In any event, there can be a delicate state of balance between the side
effects of Sinemet and its benefit.
- Disturbed sleep with abnormally vivid dreams, variable
degrees of mania or hypomania, and even outright hallucinations with
delirium can occur in some patients as a side effect of the Sinemet or
dopamine stimulation. On occasion these drug-induced hallucinations or
hypomania (psychosis) related to Sinemet have to be counteracted with other
drugs:
i.
Amitriptyline and trazodone can be helpful for sleep fragmentation.
ii.
Severely vivid dreams and hallucinations can be dampened with quetiapine
(Seroquel).
iii.
Mood stabilizers such as lithium and valproic acid (Depakote) can be also
useful in counteracting the unwanted “brain stimulation” and restlessness or
hallucinations caused by the dopamine stimulation.
iv.
Hallucinations, confusion, and psychosis can be limiting factors
sometimes preventing treatment with Sinemet even though the patient cannot
function without it.
- Other secondary drugs are added to enhance or augment
the effect of Sinemet or smooth out the side effects. These include:
- Amantadine (Symmetrel) as a dopamine agonist effect to
enhance the Sinemet, although can be associated with side effects of leg
swelling and vascular “mottling” of the legs.
- MAO-B inhibitors include selegiline (Eldepryl),
Zelapar, and rasagiline (Azilect). These drugs provide primary benefit with
regards to symptoms of Parkinson’s disease and also augment the effects of
Sinemet. Although they are MAO-B inhibitors, they are not much prone to the
side effects of the “classic” MAO inhibitors used in psychiatry for
depression.
- Entacapone (Comtan) either given as an adjunct to
Sinemet or in a primary combination with Sinemet in one pill (Stalevo).
Stalevo is a combination of three drugs, carbidopa, levodopa, and entacapone
that comes in a wide variety of dosage forms.
- Ropinirole (Requip) and Pramipexole (Mirapex) are the
two primary dopamine agonists used in either initial or secondary treatment
of Parkinson’s disease. There is no particular advantage to starting the
primary dopamine agonist as above as opposed to starting Sinemet.
Theoretical concerns that these primary dopamine agonists are “better” for
initial treatment of Parkinson’s disease and lessen chances of dyskinesias
or yo-yoing are unfounded. These primary dopamine agonists should,
therefore, be added as is necessary and clinically indicated to augment or
enhance the overall comprehensive drug plan in any given Parkinsonian
patient.
Unfortunate side effects with the
dopamine agonists (Requip and Mirapex) can include:
i.
Fluid retention.
ii.
Vivid dreams.
iii.
Agitation.
iv.
Hallucinations.
v.
Delirium.
vi.
Sudden and unexplained sleepiness or “sleep attacks.”
In any event, these dopamine
agonists need to be initiated with extreme care and caution and with clinical
expertise to help identify potential developing side effects.
e.
Anticholinergics medications such as trihexyphenidyl (Artane) and benztropine (Cogentin)
can sometimes help with a resistant tremor. However, these older treatments can
be associated with side effects of dry mouth, constipation, urinary retention,
and mental confusion, or delirium. They are sometimes avoided for these
reasons.
f.
Apomorphine injections have been touted to help attenuate dyskinesias and yo‑yoing.
However, this injection is associated with marked nausea and sometimes vomiting
and dizziness. This is not a practical pharmacologic tool.
g. Neupro (rotigotine)
patch was very helpful, but it is for the time being off the market due to
bioavailability issues.
h. Mental
“stimulants” such as Aricept (donepezil), Exelon (rivastigmine), and Namenda (memantine)
can be helpful to combat primary and secondary memory loss and confusion.
Theoretically, these drugs should have “negative” effects on the Parkinson’s
disease but they do not seem to do so. However, the main toxicities of these
mental “stimulants” include dizziness and nausea, which are often already a
problem in this type of patient.
- Non-drug treatment can include:
- Ablative cerebral surgery is done when the basal
ganglia and other accessory “motor control” centers of the brain are
“therapeutically damaged” neurosurgically to palliate symptoms, particularly
tremor.
- Deep brain stimulation (DBS) with an adjustable “brain
pacemaker” has been shown to help attenuate tremor, decrease “off” time,
lessen dyskinesia, and sometimes help troublesome gait freezing. Deep brain
stimulation can sometimes be beneficial with regards to a total “load” of
drugs necessary. Deep brain stimulation would not likely ever eliminate the
need for separate and additional drug treatment. Side effects of deep brain
stimulation include surgical complications of cerebral bleeding, brain
infection, stroke, depression, and others.
- Stem cell research carries on the possibility of
tissue transfer of new functioning cells to a diseased brain. This has not
turned about to be successful in the past even though it sounds like a good
idea. Considering the degenerative character of Parkinson’s disease, the
entire brain is affected to a certain extent with the process. At the very
least, the network of “wiring” or synopsis interconnecting brain processes
and communication are not replaced or restored even if the area of the basal
ganglia has an area of limited tissue refurbishing (transplant).
12.
In conclusion two major problems tend to cause grief as Parkinson’s
disease progresses.
- “Yo-Yoing” and “On-Off” phenomena are variable
intermittent and limited responses to treatment such that the patient waxes
and wains with ability to function interrupted by sudden periods of tremor,
rigidity, termor, and immobility. “On-Off” phenomenon can include periods
of more functional and athletic status alternating with periods of
dyskinesia or involuntary movements. “Yo-Yoing” and “On-Off” phenomena can
sometimes be dealt with by more frequent administration of Parkinsonian
medications and with addition of other augmenting medications.
- Sinemet is more effectively absorbed on an empty
stomach either 30 minutes before or 2 hours after meals. However, nausea
with the drugs sometimes requires the Sinemet to be taken with food o
requires other drugs to “protect” the stomach.
- Another discouraging problem is the development or
progression of dementia or mental and cognitive decline with time. With
this cognitive or mental decline a patient with Parkinson’s disease
sometimes becomes more sensitive to the adverse affects of the dopamine
stimulation (Sinemet). This becomes an unfortunate “catch 22.” Confusion
and hallucinations with the drugs can be intolerable while on the other hand
the patient cannot physically function without the Sinemet.
Fortunately, there are many
pharmacologic and therapeutic options with regards to Parkinson’s disease and a
long-term comprehensive approach with foresight as to the future cannot provide
optimal care.