Implant may help treat depression

A controversial implant the size of a pocket watch is now being offered as an option for Spokane patients with severe depression who have failed to respond to more conventional treatments.

The device – known as the Vagus nerve stimulator – won federal approval in 2005, but the dearth of clinical evidence has worried skeptics, including some insurance companies.

Psychiatrists at both Deaconess Medical Center and Sacred Heart Medical Center are trained to monitor the implant but cautioned that the device will be available only to patients with depression who have failed to respond to psychotherapy, medication and shock treatment.

“Is it an answer for everyone? No. But it gives some people hope,” said Tad Patterson, a Deaconess psychiatrist who has prescribed the device.

The device, which is marketed by Houston-based Cyberonics, Inc., was first used to treat epilepsy but later showed promise as a treatment for chronic depression, according to the company.

But its path to the market was questioned in a U.S. Senate committee report this year.

The committee reported that the device won approval from a top official with the Food and Drug Administration despite the objection of more than 20 staffers, who found it had not demonstrated “a reasonable assurance of safety and effectiveness.”

A study of 235 patients implanted with VNS – split into one group that had the device activated, and a second that did not – found no statistically significant difference in recovery. In a second study, Cyberonics found that 30 percent of VNS patients responded to the treatment. But the study did not have a control group, leaving no way to determine whether the device had been effective.

The lack of rigorous study worried federal regulators.

Just months before the device’s approval, one FDA medical reviewer expressed concern that “VNS might actually get an approval,” according to the Senate report.

“I feel like I can’t just sit back and watch this happen without asking if there is anything more we can do,” the reviewer wrote. “As an M.D. with an interest in science, it seems to me that such an approval would be akin to approving an experimental product.”

An FDA spokeswoman said the device was approved because of the lack of treatment options for severe depression, according to media reports.

Surgically implanted in the left side of the chest, the device periodically delivers electrical pulses to the brain via the vagus nerve. The strength and frequency of the pulses can be set and altered by a physician. As an example, the implant might operate for 30 seconds, and then turn off for five minutes, Patterson said. The device must be used in conjunction with medication and psychotherapy.

Side effects include voice alteration, shortness of breath, and a cough or tickling in the throat, the company says.

In April, health insurer Aetna Inc. announced it would not cover the $25,000 procedure because the effectiveness of the device “has not been established,” the company said in a news release. Other companies have agreed to cover the procedure.

Sacred Heart Medical Center said it has yet to approve the procedure for a patient.

“Theoretically, I’m excited about it, but clearly it’s a drastic and dramatic intervention,” said Alan Unis, medical director for psychiatry at Sacred Heart. “I want to make sure that the clinical evidence is going to back me in making this kind of recommendation.”

Unis said he would consider using the device if he locates a suitable patient.

“There is clearly a need,” Unis said. “This is a device that promises to address that need in part.”

Patterson said he has approved the device for two patients but emphasized he has set stringent requirements before a patient is considered, including failing multiple medications, electroconvulsive therapy, intensive psychotherapy and inpatient hospitalization.

“It’s too early to really know the effectiveness,” Patterson said.