Patients undergo ECT under general anaesthetic. Thaiview/Shutterstock

No evidence that ECT works for depression – new research

Many people will be familiar with electroconvulsive therapy (ECT) as a historical treatment for “mental illness”, in which an electrical current is passed through the brain to trigger seizures, with the aim of somehow treating the illness. In fact, ECT is still being administered to about a million people each year to treat severe depression, including about 2,500 in England, under anaesthetic. The majority are women, and over 60 years of age.

In a new review of the research, published in Ethical Human Psychology and Psychiatry, we suggest that there is no robust evidence that ECT works as a treatment for depression and the negative impact on patients set against any potential benefits is so appalling that ECT cannot be scientifically or ethically justified.

The evidence base

Despite its continued use, there have been no ECT vs placebo studies for 35 years. In fact, there have – surprisingly – only ever been 11 such studies, in which a control group has received the general anaesthetic but not the electricity or, therefore, the convulsion – and even these studies have been deeply flawed.

ECT enthusiasts argue the lack of any new placebo research is because it is unethical to withhold a treatment that is “known” to be effective and which definitely “saves lives”. This argument, however, means that the dwindling number of psychiatrists still using ECT are doing so outside the parameters of science in general and evidence-based medicine in particular.

In the UK, the National Institute for Health and Care Excellence (NICE) recommends the use of ECT in some cases of prolonged or severe manic episodes or catatonia where other treatment options has proven ineffective and/or when the condition is considered to be potentially life-threatening.

Although some people who have received ECT do believe it has saved their lives, there is still no study evidence that ECT is more effective than placebo for depression. Many others believe it has irreparably damaged their lives.

Other reviews and meta-analyses

My colleagues and I have previously published several reviews of the 11 studies. These have shown that there is only very weak evidence, in some of the studies, for only a minority of patients, that ECT can temporarily lift mood slightly. The reviews also demonstrated that there is no evidence whatsoever that any such effect lasts beyond the last treatment (ECT is typically administered in a series of about eight treatments).

There is also no evidence that it saves lives or prevents suicides, despite the claim by some ECT advocates that it does – a claim that is then used to justify a risk of brain damage. Brain damage has been dismissed as the wrong term but I am not sure what else to call reported persistent or permanent memory loss in between 12% and 55% of patients. It is sometimes argued that “modern” ECT is safer than it used to be, and that the memory loss is caused by the depression rather than the electricity, but there is no research evidence for either of these claims.

ECT being performed in at Winwick Hospital, 1957. University of Liverpool Faculty of Health & Life Sciences, CC BY-SA

Some have asked how come other reviews and meta-analyses conclude that ECT is effective and safe? A reasonable question that deserves an answer.

The new study, co-authored with Irving Kirsch, associate director of placebo studies at Harvard Medical School, possibly the world’s leading researcher on the placebo effects of psychiatric treatments, answers this question.

Besides analysing the 11 studies in greater detail than ever before, giving them each a quality score based on 24 methodological criteria, we also evaluated the only five meta-analyses ever conducted on this tiny, and deeply flawed, body of literature.

To guard against bias (and I am indeed biased against ECT, because of its lack of evidence base and the damage I believe it has caused to hundreds of thousands of people) my own ratings of the 11 studies were compared to blind ratings, on carefully defined criteria, by a colleague, Laura McGrath, who had no knowledge of, or particular interest in, ECT.

The five meta-analyses included between one and seven of the 11 studies and in each paid little or no attention to the multiple limitations of the studies they included.

The 11 studies we looked at had a mean quality score of 12.3 out of 24 – and eight scored 13 or less. Only four studies described how they randomised subjects and then tested this. None convincingly demonstrated that they were double-blind (where neither the participants nor the experimenters know who is receiving a particular treatment). Five selectively reported their findings. Only four reported any ratings by patients. None assessed the quality of life of patients.

There were other flaws including small study sizes, no significant differences with another treatment, mixed results (including one where the psychiatrists reported a difference but patients didn’t). Only two of the higher quality studies reported follow up data.

We concluded that the quality of the studies is so poor that the meta-analyses were wrong to conclude anything about efficacy.

There seems to be no evidence that ECT is effective for its target diagnostic group – severely depressed people, or its target demographic – older women (therein lies a broader set of issues), or for suicidal people, people who have unsuccessfully tried other treatments first, involuntary patients, or adolescents.

And given the high risk of permanent memory loss and the small mortality risk, this longstanding failure to determine whether or not ECT works means that its use should be immediately suspended until a series of well-designed, randomised, placebo-controlled studies have investigated whether there really are any significant benefits against which the proven significant risks can be weighed.

As Kirsch says: “I don’t think many ECT advocates understand just how strong placebo effects are for a major procedure like ECT. The failure to find any meaningful benefits in long-term benefits compared to placebo groups are particularly distressing. On the basis of the clinical trial data, ECT should not be used for depressed individuals.”

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