For people who had tried everything to make the sun shine, the U.S. Food and Drug Administration last summer approved a surgically implantable device that may reduce symptoms of the most tenacious type of depression.
“When I heard this device was approved by the FDA, I was happy,” said Terri Cavin, 57, of Joliet, who had the device implanted in 2002. “There are a lot of people in the boat I was in almost five years ago, who had tried everything for relief and nothing worked. That was me.”
In 1998 Cavin was diagnosed with treatment-resistant depression, or TRD, an “extremely debilitating” condition, said Dr. Daniel Maixner, a psychiatrist in the resistant-depression program at the University of Michigan Depression Center who will begin evaluating potential candidates for the device in January.
More than 120 million people worldwide are affected by depression, according to the World Health Organization, with about 20 million in the United States. The condition is one of the leading causes of disability, second only to ischemic heart disease. About 10 to 15 percent commit suicide. Antidepressant medication and psychotherapy can alleviate symptoms in many cases, but some patients, like Cavin and about 4 million others in this country, have TRD and aren’t so fortunate.
Cavin was repeatedly hospitalized for depression. She tried electroconvulsive, or shock, therapy and “tons of medications.” She attempted suicide three times.
The device she received stimulates the vagus nerve on the left side of the neck with a pacemaker-like electrical pulse generator. The device is implanted surgically on an outpatient basis under general anesthesia in most cases. A wire lead extends from the device, on the left side of the chest, and wraps around the vagus nerve in the neck. The nerve connects the brain with major organs, including the heart..
Researchers believe the intermittent pulses that stimulate the nerve cause the release of neurotransmitters in the brain, neurotransmitters associated with an elevation in mood, explained John Zajecka, associate professor of psychiatry at Rush University Medical Center.
“There’s also evidence that stimulating the vagus nerve increases blood flow to areas of the brain implicated in depression,” said Zajecka, who led a clinical trial of the device at Rush with 10 patients, including Cavin.
After implantation, doctors can adjust the device from outside the body using a magnetic wand. Patients receive a similar magnet so they can turn the stimulator off if side effects, such as hoarseness or voice alteration, cough, neck pain and difficulty breathing or swallowing, interfere with daily life. “I have a patient who is a teacher,” Zajecka said, “so he turns it off when he’s teaching.”
Vagus-nerve stimulation (VNS) isn’t new; it’s been approved for use in people with drug-resistant epilepsy since 1997 in the United States and Canada and since 1994 in Europe. It’s also been approved for depression treatment since 2001 in Canada and Europe. More than 30,000 stimulation devices, manufactured by Houston-based Cyberonics, are in use in patients around the world, according to company figures.
The device costs $16,000; add surgery and calibration and the price can run upward of $35,000, depending on the doctor and hospital. Reimbursement from third-party payers, including insurers, Medicare and Medicaid, has been made only on a case-by-case basis, but Medicare officials are weighing regular coverage.
The FDA’s approval of VNS for depression has not been without controversy. Some, including Dr. Richard Malone, a psychiatry professor at Drexel University who served on the Neurological Devices Advisory Panel of the FDA, believe that Cyberonics’ study data “did not show efficacy,” he said.
The Senate Finance Committee is investigating the FDA’s decision. A representative for the committee, Jill Kozeny, confirmed that an inquiry is under way.
In the study in which Zajecka’s patients participated, one-third of subjects showed at least a 50 percent improvement at 36 weeks; 17 percent showed complete remission at one and two years of treatment, he said. “For me, the most impressive data–and clinical experience–was that the majority of those who responded stayed well.”
Some patients reported worsening depression, but some doctors, including Zajecka and Dr. Scott Gordon, medical director of Psychiatric Consultation Services at Evanston Northwestern Hospital, which offers the treatment, attribute that to the nature of depression. “It’s such that there’s a waxing and waning course to things. Just because you have people who had worsening doesn’t necessarily mean it’s attributable to VNS,” Gordon said.
When the study ended, Cavin had the choice to have her device removed or a newer model implanted. She chose the latter.
Cavin said she has drastically reduced the amount of medication she takes for depression, and although she still has days when she feels depressed, “very seldom do I stay in bed now. I baby-sit my grandkids and have the family dinners that families have. I’ve progressively attempted more and more things.”
Patients aren’t the only ones who suffer; TRD is hard on their doctors too. When patients “come and see you and talk about the despair and hopelessness they feel, it can’t help but rub off on you as a human being,” Gordon said.
“They’re coming to you to get them better. Sometimes you have to throw up your hands and say you’ve exhausted the options. It’s nice that we potentially have another tool.”
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Requirements for implant
Who’s a candidate?
According to the FDA, the device is to be used only for patients who are:
– Over 18.
– Have a diagnosis of treatment-resistant depression.
– Have failed to respond to at least four adequate medication and/or electroconvulsive treatment regimens.
– Have been monitored by physicians with specific training and expertise in treatment-resistant depression and use of the device.
– It should be implanted by doctors trained in surgery of the carotid sheath and trained to implant the device.
– Vagus-nerve stimulation is an adjunctive treatment, meaning it is meant to be used with, not in place of, other therapies.
–K.R.
