The Evolving State of Electroconvulsive Therapy

For nearly 100 years, doctors have used electroconvulsive therapy (ECT), a treatment that stimulates the brain with electric currents to trigger a brief seizure, to help people having an episode of major depression. While ECT is remarkably effective, it can come with debilitating neurocognitive side effects. To reduce the ill-effects, clinicians have altered the treatment significantly over the past few decades and continue to tweak it to best keep its efficacy while reducing its incapacitating after-effects. A new meta-analysis published in the Journal of Clinical Psychiatry suggests that a method using ultra-brief pulses of stimulation is nearly as effective as traditional ECT—with far fewer cognitive side effects.

The side effects

Writer Lucy Tallon described her personal experience with ECT in an article for the Guardian in 2012.

“So what is it actually like?  You go in, have your blood pressure taken, sign a form, lie down, go to sleep, wake up with a slight headache and go home. And often, you feel instantly better,” she explained in the piece. “The memory lapses that follow treatment are a bore, but that passes. The first few times, I didn’t remember arriving at hospital that morning. But for up to three months after a course of treatment, I can still forget names, routes, and what I was just thinking. Some people experience it more severely but in the vast majority of cases, the memory eventually returns to normal.”

ECT is highly effective, but for those some Tallon mentions, its efficacy comes at significant cost. Christopher Abbott, medical director of the electroconvulsive therapy service at the University of New Mexico School of Medicine, says that ECT does not result in negative side effects for everyone—but those who do show effects generally report memory loss.

“We see a continuum between, ‘Yeah, I’m a little bit forgetful,’ more of a mild nuisance, to people who have a dramatic drop in their cognitive function,” he says. “For some, the neurocognitive impairment is very bad, taking someone who was at a pretty good level of functioning to a place where they can no longer work and can’t handle a lot of activities of daily living. So when you decide to use ECT, you have to do a thorough cost/benefit analysis between the depression and the possible side effects of the treatment.”

An evolving procedure

Clinicians have been trying to optimize ECT for decades, says William Regenold, a psychiatrist at the University of Maryland department of psychiatry.

“Back in the 16^th century, people were trying to improve mental illness by causing convulsions. It wasn’t until 1938 that we had the idea to induce those seizures electrically—and the rationale was to make it safer and more reliable,” he says. “But since then, people have done various things to see if they can adjust the electricity, lower the dose, and do other things to retain the benefits but minimize the adverse effects. And we’re still working on trying to do that.”

One such adjustment has been for the length of the electrical pulses. Studies suggest that shorter pulses of stimulation, called ultra-brief pulse stimulation, may better strike the balance between efficacy and side effects, says Colleen Loo, director of the Sydney Neurostimulation Centre in Australia.

“With ECT, it looks like the stimulus goes for a few seconds, but it’s actually a series of short pulses. The standard form of ECT used today is called brief pulse because each pulse is on the order of about one millisecond, or one thousandth of a second,” she says. “But ultra-brief is even shorter, at 0.3 of a millisecond. Basic-science research suggests that those ultra-brief pulses may be more ideal for stimulating the brain, giving you more of a response for a lesser amount of energy put in.”

But while the results of a handful of randomized controlled trials suggest that ultra-brief pulse was effective, a systematic meta-analysis of those studies had not yet been done. Loo and her colleagues did just that, and learned that while ultra-brief pulse ECT was not quite as effective as traditional ECT, it was much less likely to result in cognitive side effects. The meta-analysis, comprised of six international trials and nearly 700 patients, was published in the July 2015 issue of the Journal of Clinical Psychiatry.

“Traditional ECT is the strongest of the treatments. But the pooled results show that the ultra-brief pulse ECT is also quite effective—and shows far fewer side effects,” says Loo. “This is reassuring because it means we can recommend it to clinicians and say, yes, this is an appropriate new way to do ECT. This is another option you can look at when you are determining the best treatment for your patient.”

The future

Loo, Regenold, and Abbott all stress that, despite a terrible reputation, ECT is a valid medical procedure proven to be effective and safe. It is often the treatment of last resort for people with severe depression—and one that can, like in Tallon’s case, provide welcome and necessary relief. But, that said, Regenold says that he hopes to see the treatment further evolve.

“I’d like to see the field move in a direction where we start asking questions about whether a seizure is even necessary, whether other less invasive techniques may be appropriate, and more research about what we should be doing for different patient populations,” he says. “What we need is a better sense of what sort of patient needs what sort of treatment—and what’s really happening in the brain before and after treatment for those different people.”

Abbott agrees. “ECT works, we know that—but what often happens is that we solve one problem, the depression, and then create other problems with neurocognitive impairment,” he says. “So I think a realistic expectation, in our lifetimes, is to have an evidence-based, individualized set of stimulus parameters. We don’t want to just use ultra-brief pulse ECT on everyone because we might undermine the effects for some patients. But if we can learn more about the different cortical networks we need to stimulate, and how to best stimulate them with the least amount of impairment, that would be a huge step in optimizing our ability to help cure our patients of major depressive episodes.”