Depression:
Vagus Nerve Stimulation (VNS)
Transcript:
Guest: Dr. Ziad Nahas – Psychiatry & Behavioral
Sciences
Host: Dr. Linda Austin – Psychiatry
Dr.
Linda Austin: I’m Dr. Linda Austin. I’m interviewing Dr. Ziad Nahas who is
Associate Professor of Psychiatry and Director of the Mood Disorders Clinic
here at the Medical University of South Carolina. Dr. Nahas, let’s talk about VNS, vagal nerve
stimulation. What is VNS?
Dr.
Ziad Nahas: Vagus nerve stimulation is,
essentially, a brain stimulation technology by which a pacemaker is delivers
electrical stimulation to the vagus nerve, a nerve that runs down by the main
blood vessels in the neck. We take
advantage of the vagus being primarily a nerve that takes information from the
periphery of the body into the brain to then carry on information with the type
of stimulation we deliver. So,
ultimately, the effect, although we’re stimulating a rather peripheral nerve,
is happening in the brain.
The
device and the technology was first tested in the 90s for treatment of refractory
epilepsy and showed that it had a clinically significant effect on regulating
the number of seizures and being an adjunctive valuable therapeutic
intervention. And then, shortly after
that, in the late 1990s, it got tested for depression. Actually, the first implant took place here
at MUSC. And since then, there were
larger studies and multicenter trials, some equivocal results but, ultimately,
an FDA approval. And it is considered
the only brain stimulation technology and the only antidepressant treatment,
actually, that is indicated for the treatment of depression.
Dr.
Linda Austin: Who is a good candidate
for this treatment?
Dr.
Ziad Nahas: Obviously, because of the
nature and the invasiveness, it still requires surgery. Although it’s not brain surgery, it’s still
rather invasive. One would need to
document a substantial level of treatment for depression. And what we mean by that is that not only at
the time you’re being evaluated, you’re severely ill, in terms of the type of
symptoms you’re exhibiting, but that you’ve been treated with different
treatment that is classically known to be reasonable treatment for depression,
at a good enough dose for a long enough period of time, you took some without
having too many side effects, and then you still failed. And, at least in our clinic, we have put the
benchmark for different failed antidepressants and a current depressive episode
such that we feel that we have enough documentation for the necessity to move
forward into a more aggressive treatment.
Dr.
Linda Austin: And, of those patients who
by definition are pretty sick people and pretty resistant to treatment, what
percentage have at least some response to VNS?
Dr.
Ziad Nahas: Well, with the treatment
trials, the results I mention earlier were a little bit equivocal because, at
the three-month benchmark, VNS really did not do better than other
treatment. However, at one year, it
showed about a 30 percent response. And
when you compare its response to equally severe patients being clinically
managed by their psychiatrist, VNS, added to their ongoing treatment, doubled
their chances of getting better. So
then, by one year, if you are implanted with the device, you have a one in
three chance of getting better. But, it’s two times better than if you were to
not get the treatment.
Dr.
Linda Austin: If a patient were
interested in getting this treatment, where would they go at MUSC?
Dr.
Ziad Nahas: We have set up the Mood
Disorder Clinic primarily to act as a first clinical translation to the new
technologies for depressed patients. So,
at MUSC, we have the Mood Disorder Clinic, in which we mainly deal with
tertiary referrals and kind of a second opinion evaluation for the treatment of
depression, in which we can evaluate patients for their candidacy for vagus
nerve stimulation.
The
procedure, primarily, requires contacting the scheduling office of the Institute of Psychiatry and formally stating that a
patient is interested in a vagus nerve stimulation evaluation. The person taking that call will then know
how to direct them and essentially get them hooked up with our nurse who would
primarily do, first, a phone screening, to give them an idea of the approach
and the needed documentation. We try to
do a lot of homework because, as we said, this is a rather invasive procedure,
and we need to show the necessity to move forward. And then we ultimately do an evaluation
face-to-face.
The
concern, really, lies in the hesitancy by the insurance company to readily pay
for the procedure. This is rather
costly. And because of some of the
earlier equivocal results that I mentioned, the insurance companies, in
general, have said that this is still experimental despite the fact that is has
US FDA approval. Aside from having
clinical evaluation to see if the patient really would benefit from this,
there’s also the financial hurdle of either having to consider paying
out-of-pocket or going through quite a bureaucratic phenomenon to essentially
get the preauthorization required from an insurance carrier. We have been lucky in getting those, but it’s
not an easy route.
Dr.
Linda Austin: Do you know how much it
costs if you pay out-of-pocket?
Dr.
Ziad Nahas: At MUSC, we have a flat rate
of $28,000. That will cover the cost of
the surgery evaluation, the surgery itself, and the implanted device. It does not cover the initial evaluation from
the clinical psychiatric stand point, nor the follow-ups for maintaining and
monitoring the vagus nerve stimulation throughout.
Dr.
Linda Austin: Thank you so much.
Dr.
Ziad Nahas: You’re welcome.
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.