New Shock Therapy Procedure Works With Fewer Side Effects

From the WebMD Archives

May 15, 2000 -- Electroconvulsive therapy (ECT) can be an effective treatment for depression, particularly when other treatments have failed, but the memory loss associated with it makes some people afraid.

However, two new studies point to a new way to administer the treatment that achieves positive results similar to the traditional way, but with fewer bad side effects.

Traditional ECT usually requires that a shock be administered to both sides of the brain. But giving a higher level of shock to only the right side of the brain produces fewer memory problems and can be as effective as giving high-level shocks to both sides of the brain, according to the studies in the May issue of the Archives of General Psychiatry. The catch is that FDA regulations limit the amount of electricity that current equipment can produce to a level that is below the level researchers found to be most effective. Questions still remain about exactly which level of shock will produce the best effect.

The problem is that patients in older age groups, the group most patients fall into, need a high amount of shock to produce a good effect, according to Richard Abrams, MD, of the Chicago Medical School in Illinois. "Existing ECT devices cannot give enough electrical energy because of the limitations imposed upon them," says Abrams, who also is director of Somatics Inc., a company that manufactures and distributes ECT equipment.

Abrams wrote a commentary published in the same issue of the Archives of General Psychiatry in which he urges the FDA to act to allow high-stimulus ECT devices in the U.S. Such double-dose devices are routinely available in other parts of the world, including the United Kingdom, Canada, and Mexico.

"I agree with Abrams that the FDA has no scientific basis for limiting the output of ECT devices to the level they are now limited to. There's no justification for limiting the devices to the amount of energy arbitrarily established in 1984. ... The people in Europe and other parts of the world where they don't have that restriction really are better off," says Max Fink, MD, of Long Island Jewish Medical Center/Hillside Hospital in Queens, N.Y.

All those who spoke with WebMD reiterated the need for equipment that would allow high-intensity stimulation to the right side of the brain. A FDA spokesperson tells WebMD that the Center for Devices and Radiological Health has to review the relevant material and has no official response at this time.

In the first study, Harold A. Sackeim, PhD, and other investigators at the Columbia University College of Physicians and Surgeons in New York compared the effects of giving low, moderate, and high levels of shock to one side of depressed patients' brains, and giving a moderate level of shock to both sides. Depression and mental function were assessed before, immediately after, and two months after the treatment. Cognitive tests included an evaluation of different types of memory function, including the ability to remember events prior to treatment and after treatment. Patients were monitored for relapse for a year.

About two-thirds of patients responded to the high-dosage treatments. These response rates were about twice that as seen in the low-dosage and moderate-dosage groups who received a shock to one side of the brain.

However, the high-intensity treatment to the right side of the brain produced less severe and persistent bad side effects on learning and memory than the treatments involving both sides of the brain. One week after treatment, patients who received a shock to both sides of their brains were 71% more likely to not remember facts about their lives that they had reported at the beginning of treatment.

In the second study, W. Vaughn McCall, MD, MS, and colleagues found that the best results were achieved through higher doses of electricity. "You need to use relatively large doses," says McCall, who is with the departments of psychiatry and behavioral medicine at Wake Forest University School of Medicine in Winston-Salem, N.C. "But we also had more side effects" at those levels, McCall tells WebMD.

McCall says that in 1990, the American Psychiatric Association's Task Force on ECT suggested that a moderate dose of electricity to the right side of the brain should be used. But doctors interpreted this to be a level that didn't help "nearly as many people as would be expected."

As far as side effects, McCall urges physicians and patients to consider what are the most important goals of therapy: the antidepressant response or avoidance of side effects. He says that most memory problems seen after treatment are only temporarily bothersome to patients. Problems with being able to remember events after therapy are seen within the first two weeks following treatment, but soon return to normal. Patients do experience some permanent loss of memories that were made prior to treatment.

"For most patients, this is not a big deal," says McCall. "I always discuss this with my patients prior to ECT. It is almost never an issue for them. Their memories of being depressed are not too precious to them, and they're willing to sacrifice them."

Vital Information:

  • Electroconvulsive therapy (ECT), or shock therapy, is used to treat depression in patients who do not respond to other treatments, such as medication or psychotherapy.
  • One side effect of the treatment is memory loss, but new research shows that giving ECT at a higher intensity to only one side of the brain, instead of both sides of the brain, reduces the chance of memory loss.
  • Currently, U.S. physicians cannot administer treatment in this manner, because the FDA does not allow the machines to deliver these higher doses of electrical energy.