ECT for Depression May Cut Suicide Risk by Nearly 50%

Patients hospitalized for depression who received electroconvulsive therapy (ECT) had a nearly 50% reduced risk of suicide death over the following year versus comparable patients who did not receive ECT. The findings came from a detailed analysis of over 67,000 hospital records from patients seen in psychiatric inpatient units across Ontario, Canada.

The analysis, published in Lancet Psychiatry, also found that patients who received ECT were less likely to die from other causes within one year after discharge.

The findings provide further evidence that ECT can be a lifesaving treatment for patients with severe depression, said lead author Tyler Kaster, M.D., Ph.D., an assistant professor of psychiatry at the University of Toronto and medical head at the Temerty Centre for Therapeutic Brain Intervention.

Kaster and colleagues used Canadian registries to examine the 12-month mortality outcomes of all adults aged 18 and older in Ontario who spent more than three days hospitalized for unipolar or bipolar depression between April 1, 2007, and December 31, 2017. Individuals were included in the analysis multiple times if their hospitalizations occurred more than 12 months apart. The final sample included 67,327 hospital admissions, during which 4,982 patients received ECT.

A total of 450 deaths from suicide occurred within 12 months of discharge from the hospital; this included the deaths of 27 people who received ECT (5.84 per 1,000 person-years) and 423 who did not receive ECT (7.26 per 1,000 person-years).

After adjusting for more than 100 demographic and medical variables that might influence whether a hospitalized patient would be a good candidate for ECT (such as age, psychotic symptoms, and physical comorbidities), the researchers found that patients who received ECT in the hospital had a 47% reduced risk of suicide death and a 25% reduced risk of any death over 12 months compared with those who did not receive ECT. Additional analysis revealed that suicide risk reduction was more pronounced in patients with unipolar depression than in patients with bipolar depression.

Kaster and colleagues estimated that for every 200 hospitalized patients treated with ECT, one suicide will be prevented, which is about the same benefit seen with lithium treatment among people with bipolar disorder. Kaster said that while the number of suicides prevented by ECT may appear low, it is meaningful as suicide is a very rare event.

Kaster noted that previous research he conducted also found no evidence that patients hospitalized for depression who received ECT were at an increased risk of serious medical events, compared with patients who did not receive ECT.

While ECT is not for every depressed patient, Kaster said he hoped that the medical event and mortality data would provide further support that ECT is a medically safe procedure.

“[ECT] is still the most invasive treatment for depression we have and any decision to proceed has to be made very thoughtfully, weighing all the benefits and risks,” he said.

This study was supported by the Canadian Institutes for Health Research, Norris Scholars Award, and University of Toronto. ■