New treatment for resistant depression
Vagus Nerve Stimulator (VNS) Therapy™, a treatment for depression using an implanted device manufactured by Cyberonics, Inc., Houston, TX, was approved for the treatment of treatment-resistant depression by the U.S. Food & Drug Administration in July 2005. VNS Therapy is also approved for use in Europe and Canada for depression in patients with treatment-resistant or treatment intolerant major depressive episodes including unipolar depression and bipolar disorder (manic depression).
What is VNS?
The device is a totally implanted vagus nerve stimulator (VNS) for the long-term treatment of chronic or recurrent treatment-resistant depression. The device is to be used only in patients 18 years of age or over who have failed to respond to at least 4 medication and/or ECT treatment regimens prescribed by their physician. The device was initially approved in 1997 for epilepsy. To date, more than 30,000 patients have been treated with VNS Therapy. Many of the patients with epilepsy who were treated with VNS Therapy reported improved mood and subsequent clinical studies demonstrated this improvement.
How does it work?
During a short, outpatient procedure, a pulse generator, similar to a pacemaker, is surgically implanted just under the skin of the left chest area and an electrical wire is connected from the generator to the left vagus nerve. Once activated by the physician, the device sends precisely timed and measured mild electrical pulses to the left vagus nerve. These signals are in turn sent to the brain. To turn the stimulator off, the patient holds a magnet over the generator. VNS Therapy modulates blood flow and/or metabolism in many areas of the brain that are affected in mood disorders.
How effective is VNS Therapy?
This therapy may be required for several months before any benefit is noticed by the patient. In a clinical study, during the first three months of therapy, patients who had the device implanted and turned on did not show any significant advantage over patients in whom the device was implanted but not turned on. At one year, two or three out of every 10 subjects had a clinically significant improvement in symptoms of depression with about half that number having almost no remaining depressive symptoms. Many of the patients who had a significant response within the first year of treatment continued to have a similar degree of response through two years.
Some patients, however, had no improvement in symptoms and some actually got worse. This therapy is intended to be given along with other traditional therapies, such as medications and ECT, and patients should not expect to discontinue these other treatments, even with the device in place. Patients will require regular visits to their physicians for adjustments to their device and other treatments.
Vagus Nerve Stimulator (VNS) Therapy™ is a controversial treatment. Its FDA approval and review in a psychiatric journal have come under fire by the US Senate Committee on Finance, the Wall Street Journal, and medical publications.
Are there side effects?
The U.S. FDA reports that patients receiving VNS therapy may experience various side effects including hoarse voice, cough, shortness or breath, difficulty swallowing, and neck pain, some of which may persist as long as the device is active. According to Cyberonics, Inc. VNS Therapy is well tolerated and there are no drug interactions with VNS Therapy and concurrent antidepressant medication.
Will my insurance cover VNS therapy?
Cyberonics, Inc. reports that through September 2006, case by case approvals and/or reimbursement have been obtained from 248 different payers. Most state Medicaid agencies have yet to develop their own coverage policy for VNS Therapy for depression and a national coverage decision from Medicare has not yet been developed. Cyberonics, Inc can provide you with information specific to your state.