Movement
Disorders: Essential Tremor
Transcript:
Guest: Dr. Vanessa Hinson - Neurology
Host: Dr. Linda Austin – Psychiatry
Dr.
Linda Austin: I’m Dr. Linda Austin. I’m interviewing Dr. Vanessa Hinson who is
Assistant Professor of Neurology and Director of the Movement Disorders Program
here at MUSC. Dr. Hinson, let’s talk
about a pretty common condition, essential tremor. What is an essential tremor?
Dr.
Vanessa Hinson: Essential tremor, first
of all, is the most common movement disorder that we encounter. Essential tremor refers to shaking of the
hands that happens when the patient holds out their hands in front of them or
wants to use their hands. It can also
affect the head and the voice. Usually,
this tremor runs in families; it’s genetic.
We often get a positive family history from the patient when they tell
us that their mother had the same problem, father had it. It is autosomal dominant, so 50 percent of
affected relatives can pass it to another family member. So, it’s very common, it’s genetic, and
mostly affects the hands, but can affect the head and voice as well.
Dr.
Linda Austin: At what age does it
appear?
Dr.
Vanessa Hinson: It occurs most commonly
at around 50 or 60 years of age and, unfortunately, often worsens as one gets
older. It can also occur in children. This is more unusual, but our pediatric
neurology colleagues also treat children with essential tremor.
Dr.
Linda Austin: When you think of older
people, certainly, it seems that tremors are extremely common. In fact, characatures of older people often
show them with a tremor. Is there such a
thing as just a tremor of old age that does not seem to be genetic?
Dr.
Vanessa Hinson: No. I don’t think there’s any normal form of
tremor. I think most people with a
benign tremor that is not functionally interfering, and that they’re older,
actually have essential tremor. Essential
tremor is so common. And many of us now
grow very old with all the available medical care that we just see so much of
it and we think it’s normal, but it’s not.
It’s
very important, though, to not take any form of tremor for essential tremor just
because it’s common. There are many
other causes of tremor, especially in the elderly. Let’s take the example of medication-induced
tremor. There are many medicines that
can cause tremor. The tremor would look
exactly like essential tremor. For example,
antidepressants, many of us take the so-called SSRIs, like Prozac or Zoloft,
and these medicines can produce a tremor that looks just like essential
tremor. So, it would take changing that
medication to something else and see if the tremor would go away in order to
define what we’re dealing with. So,
taking a detailed medical history is very important.
The
other very important task, for the neurologist, is to make sure this is not
Parkinson’s disease. Obviously,
Parkinson’s is also much more common in the elderly, so we have to perform a
detailed neurological examination to test for that. There is not blood test or brain scan that
would show essential tremor or Parkinson’s disease, so one relies on a clinic diagnosis.
Dr.
Linda Austin: What is the difference in
tremor in those two disorders?
Dr.
Vanessa Hinson: The Parkinsonian tremor
is a tremor that occurs at rest. ,
somebody would sit in a chair and their hand would shake fairly slowly at a set
frequency, and the shaking would go away when they do something with their
hands. So, when a Parkinson’s disease
patient, in the earliest stages, eats, for example, holds a fork and brings the
food to their mouth, they have no shaking, yet when they relax and watch
television, their hands start shaking.
We call this a rest tremor, whereas essential tremor happens with
action. It’s almost the opposite. It happens when the patient wants to do
something with their hand and it quiets down at rest.
The
other difference is, and this is a very important difference, that Parkinsonian
tremor always starts on one side of the body.
So, the patient comes in and says, I
have a right hand tremor, the left hand is normal. That makes me think of Parkinson’s disease,
whereas if the patient says, I have a
tremor in both of my hands, it’s equally bad on both sides, that makes me
think of essential tremor.
Dr.
Linda Austin: I’ve seen drug-induced
tremors that can start on one side.
Dr.
Vanessa Hinson: That would usually be a
Parkinsonian drug-induced tremor, because certain drugs, especially used in
psychiatry, can lead to Parkinsonism that starts on one side of the body. It would still be a Parkinsonian tremor
though, but induced, probably, by a neuroleptic, which is one of the medicines
that can induce a Parkinsonian tremor.
Other drug-induced tremors can be worse on one side, but if you look
closely, the other side is also affected, probably not as much as the original
side, but there’s some involvement on both sides.
Dr.
Linda Austin: How do you treat an
essential tremor?
Dr.
Vanessa Hinson: Treatment for essential
tremor can be quite rewarding because there are two medicines that are quite
effective. These medicines have been on
the market for a long time and we know, very well, how to use them. One is a beta blocker called propranolol that
we also use to treat high blood pressure.
The other drug is a medicine called Primadone (Mysoline), which was
originally developed to treat seizures but, very effectively, suppresses
tremor.
Usually
we start with one of these two medicines.
And if we don’t get relief or if the patient doesn’t find that this is
useful, we can resort to the tertiary or more rarely used medications. But there are also other options we have with
medicines. If a patient does not respond
to oral medication, we can also offer deep brain stimulation surgery here at
MUSC, which is a surgical approach to treating tremor that is very effective.
Dr.
Linda Austin: How about new research
studies in this area, is there anything going on at MUSC.
Dr.
Vanessa Hinson: Researchers have focused
on developing new drug treatments for essential tremor. There is a new research study, at MUSC, that
we’re just starting with that patients can be part of, through the Movement
Disorders Program, that looks at a new compound called pregabalin that we also
use for the treatment of pain disorders, for example, that has, in preliminary
studies, proven to be very successful in patients with essential tremor. So, we will study this, actually, in many sites
throughout the country, and we are one of the sites. Patients would be assigned to taking this new
drug, for essential tremor, or a placebo pill, which will not have any active
compound for tremor, and we’ll see which group of patients does better.
Dr.
Linda Austin: If a person is interested
in enrolling in that study, who should they contact?
Dr.
Vanessa Hinson: They should contact the
MUSC Movement Disorders Program at (843) 792-7262 or go to the Movement
Disorders website through the main MUSC Health website.
Dr.
Linda Austin: Good luck with the study.
Dr.
Vanessa Hinson: Thank you.
Dr.
Linda Austin: Thanks a lot for being on
this podcast.
Dr.
Vanessa Hinson: Thank you.
If you have any questions about the services
or programs offered at the Medical University of South
Carolina or if you would like to schedule an
appointment with one of our physicians, please call MUSC Health
Connection: (843) 792-1414.