Frequently Asked Questions

Yes, in participants with markedly treatment-resistant major depression who had clinically meaningful suicidal ideation at baseline, adjunctive active vagus nerve stimulation was associated with more months of clinically meaningful improvement in suicidal ideation than sham stimulation over months 3 (OR = 1.43; 95% CI, 1.0042.021; P = .047). The study defined clinically meaningful improvement a priori as a 3-point or greater reduction on its composite suicidal ideation score. The authors describe this as an exploratory finding rather than a definitive antisuicidal effect.

Yes, but the remission signal was strongest late in the blinded phase. Among participants who started with meaningful suicidal ideation, active vagus nerve stimulation was associated with significantly more months in suicidal ideation remission during months 1012 than sham stimulation (OR = 1.67; 95% CI, 1.0072.763; P = .047). Over the full 12 months, the difference in remission was not statistically significant (OR = 1.38; 95% CI, 0.9541.981; P = .087).

The study did not find evidence that active vagus nerve stimulation worsened suicidal ideation. In participants who already had meaningful suicidal ideation at baseline, meaningful worsening was limited and no meaningful difference was identified between active and sham stimulation. In participants without clinically meaningful baseline suicidal ideation, emergence of meaningful suicidal ideation during the 12-month study period was infrequent and did not differ between groups (OR = 1.24; 95% CI, 0.493.11; P = .650).

Improvement appeared gradual rather than acute. In participants with meaningful baseline suicidal ideation, both active and sham groups showed substantial declines in the composite suicidal ideation score starting at month 3, and reductions increased from months 3 to 12 across both groups (visit effect P<.001). By month 12, the mean (SD) drop in score was 2.42 (0.19) with active stimulation and 2.12 (0.19) with sham stimulation, while the overall treatment group effect showed only a trend (P = .091).

The study used a prespecified composite suicidal ideation score that combined 3 suicide items: MADRS item 10, QIDS-C item 12, and QIDS-SR item 12. The MADRS suicide item was rescaled to match the 03 scoring of the QIDS items, producing a total composite score from 0 to 9, with higher scores indicating greater suicidal ideation. The investigators defined 02 as no or minimal ideation, 3 or higher as meaningful suicidal ideation, and a change of 3 or more points as a clinically meaningful change.

This was a markedly treatment-resistant unipolar depression cohort. The analytic sample included 463 participants aged 18 years or older with a current nonpsychotic major depressive episode, at least 4 adequate antidepressant treatment failures in the current episode, and at least moderately severe depression at baseline. Participants averaged about 29 years of lifetime depression, 13 failed antidepressant treatments, 71.0% had failed at least 1 interventional treatment in the current episode, and 40.4% had attempted suicide.

No. The article states that vagus nerve stimulation is not an acute intervention for suicidal ideation or suicidal behaviors, and the benefit pattern in this trial was gradual over months rather than immediate. The findings are therefore more relevant to longer-term management of suicidal ideation in markedly treatment-resistant major depression than to acute suicidal crisis.

RECOVER was a multicenter, randomized, triple-blind, sham-controlled 12-month trial of adjunctive active versus sham vagus nerve stimulation with treatment as usual. The suicidal ideation analyses in this report were exploratory, the trial was not designed or statistically powered specifically to detect a treatment effect on suicidal ideation, and no correction for multiple comparisons was applied. The reported P values and confidence intervals were therefore presented as descriptive rather than confirmatory.

These findings apply most directly to adults with markedly treatment-resistant, nonpsychotic unipolar major depression, especially those with chronic clinically meaningful suicidal ideation at baseline. They do not necessarily generalize to patients with severe suicidal intent or behavior, because RECOVER excluded participants with severe suicidal intent or behavior at baseline to reduce risk during a blinded trial that included a sham condition.

The main limitations were that the suicidal ideation analyses were exploratory, the trial was not powered specifically for suicidal ideation outcomes, and the composite suicidal ideation score used in the report was novel and had not been validated in other settings. The authors also note that the findings may not generalize to patients with suicidal intent, because those with severe suicidal intent or behavior at baseline were excluded.