Summary: A large new meta-analysis finds that electroconvulsive therapy (ECT) substantially lowers the risk of suicide and overall mortality in people with severe, treatment-resistant depression. Pooling data from 26 high-quality studies, researchers compared nearly 18,000 patients who received ECT with more than 25,000 patients treated with standard care and found a 34% reduction in suicide deaths and a 30% reduction in all-cause mortality associated with ECT.
Beyond lowering suicide risk, ECT was associated with a moderate decrease in suicidal thoughts, suggesting benefits that extend beyond symptom relief. The review also examined newer neurostimulation methods—repetitive transcranial magnetic stimulation (rTMS) and vagus nerve stimulation (VNS)—but available data were too limited to support firm conclusions about their effect on suicidality.
Key facts
- Suicide reduction: Patients who received ECT had 34% fewer suicide deaths compared with those receiving standard treatment.
- All-cause mortality: ECT recipients showed a 30% lower risk of death from any cause.
- Stronger modern effect: More recent, larger studies report greater benefits, suggesting current ECT practice may be more effective than earlier approaches.
Source: ECNP
A systematic review and meta-analysis led by researchers at the University Psychiatric Clinics Basel synthesised the best available evidence on neurostimulation therapies for people with severe or treatment-resistant depression. The analysis focused on outcomes related to suicidal behaviour, suicidal ideation, and overall mortality, and is published in the journal Neuroscience Applied.
Lead author Dr. Timur Liwinski commented that this is the first meta-analysis to demonstrate a survival benefit for ECT in depression. He noted that ECT remains the most effective available treatment for severe depression and that the analysis shows reductions in both suicide and all-cause mortality.
Depression, suicide and the need for effective interventions
Major depressive disorder affects hundreds of millions worldwide and remains a leading contributor to suicide. Each year nearly 700,000 people die by suicide, many of whom have underlying mood disorders. Individuals with major depression face dramatically increased suicide risk, and effective interventions for those who do not respond to first-line treatments are a critical public-health priority.
Study design and included data
From an initial search of 1,352 studies, the research team selected 26 that met strict inclusion criteria for quality and relevance. The final set included randomised and controlled observational studies that reported on treatment methods, suicide deaths, suicidal ideation, and overall mortality following neurostimulation treatment.
Eleven of those studies focused on ECT. Across these, 17,890 people treated with ECT were compared to 25,367 patients receiving standard care. In the ECT group there were 208 suicide deaths; in the control group there were 988. For all-cause mortality, there were 511 deaths in the ECT group and 1,325 in the control group.
Findings
The pooled results indicate that ECT is associated with a 34% reduction in suicide deaths and a 30% reduction in deaths from any cause among people with severe or treatment-resistant depression. ECT recipients also reported a modest decrease in suicidal ideation.
For rTMS, the body of evidence reporting suicidality outcomes was small and inconsistent, making it difficult to draw reliable conclusions. VNS appeared to be associated with a marked reduction in all-cause mortality in the limited studies available, but small sample sizes and study design limitations reduce confidence in that finding.
The authors highlight that more recent studies tend to show larger benefits from ECT. This pattern may reflect improvements in how ECT is delivered—modern protocols, anaesthesia practices, and electrode placement have evolved since the technique’s early use in the 20th century—so contemporary ECT care may offer stronger protections than historical data alone would suggest.
Limitations and interpretation
Most included studies were observational rather than randomised controlled trials, which limits the certainty of causal claims. Selection factors—such as which patients are offered or accept ECT—may influence observed differences in mortality. The authors therefore advise cautious interpretation while noting the practical and ethical challenges of conducting long-term randomised trials in severely suicidal populations.
Independent commentators note the value of this synthesis: it provides clearer, quantitative evidence that ECT reduces suicidality and may lower overall mortality among people with refractory depression, while also urging careful assessment of potential confounding factors.
Brief overviews of the techniques
Electroconvulsive Therapy (ECT): A well-established, clinically administered procedure in which brief general anaesthesia and a muscle relaxant are used while a controlled electrical stimulus induces a short seizure. ECT modulates several neurotransmitter systems and is used for severe, treatment-resistant depression.
Repetitive Transcranial Magnetic Stimulation (rTMS): A non-invasive technique delivering magnetic pulses to targeted brain regions to generate electrical currents that activate neuronal circuits. rTMS is often used when conventional treatments fail.
Vagus Nerve Stimulation (VNS): An implanted device sends periodic electrical pulses to the left vagus nerve to influence brain activity. VNS is reserved for patients who have not benefited from other therapies.
About this research news
Author: Tom Parkhill
Source: ECNP
Contact: Tom Parkhill – ECNP
Image: The image is credited to Neuroscience News
Original Research: Open access. “Electroconvulsive Therapy Reduces Suicidality and All-Cause Mortality in Refractory Depression: A Systematic Review and Meta-Analysis of Neurostimulation Studies” by Timur Liwinski et al., Neuroscience Applied.
Abstract
Electroconvulsive Therapy Reduces Suicidality and All-Cause Mortality in Refractory Depression: A Systematic Review and Meta-Analysis of Neurostimulation Studies
Depressive disorders are widespread and contribute to a large share of suicides worldwide. There is substantial evidence that ECT and rTMS reduce depressive symptoms in difficult-to-treat cases, but their roles in preventing suicide and lowering all-cause mortality have been debated. This systematic review and meta-analysis searched MEDLINE via PubMed through 9 January 2024 for trials and controlled observational studies that reported suicide and mortality outcomes after neurostimulation treatments for depression, and synthesised the available evidence to assess their impact on suicidality and overall survival.