Early suicidal ideation change and suicidality-associated emergency department utilization after ketamine or esketamine treatment in treatment-resistant depression.
Liliana Patarroyo-Rodriguez, Vanessa K. Pazdernik, Jennifer L. Vande Voort, Simon Kung, Balwinder Singh
Ther Adv Psychopharmacol May 22, 2026 DOI: 10.1177/20451253261450747 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Retrospective cohort study Peer reviewed |
|---|---|
| Sample size | 96 |
| Population | Individuals with treatment-resistant depression who had suicidal ideation data during acute treatment and 6-month follow-up data on suicide-associated emergency department visits |
| Interventions | Ketamine Esketamine |
| Duration | Acute treatment up to six intravenous or eight intranasal treatments; 6-month follow-up |
| Measures | Quick Inventory of Depressive Symptomatology – Self Reported (QIDS-SR) item 12 |
| Topics | Depression Esketamine Ketamine |
| Key findings | Early improvement in suicidal ideation during acute ketamine or esketamine treatment was associated with fewer suicide-associated emergency department visits over six months, but the primary analysis was not statistically significant (OR 0.16, p=0.12). A secondary analysis found that a 50% or greater reduction in suicidal ideation after two intravenous ketamine infusions was associated with lower odds of any post-treatment visit (OR 0.17, 95% CI 0.02-0.98, p=0.047). |
Abstract
Background: Ketamine and esketamine ((es)ketamine) rapidly reduce depressive symptoms and suicidal ideation (SI) in treatment-resistant depression (TRD), but whether early SI improvement during the acute phase of the treatment predicts reduced suicide-associated emergency department (SAED) visits over the longer term remains unclear.
Objectives: To examine whether early improvements in SI, measured using item 12 of the Quick Inventory of Depressive Symptomatology – Self Reported (QIDS-SR), following (es)ketamine treatment are associated with SAED visits over 6 months
Design: Retrospective cohort study.
Methods: Individuals with TRD who had available data on SI measured using the QIDS-SR during the acute phase, as well as data on SAED visits over 6 months, were included. Participants were classified based on changes in SI as resolved, partially improved, or unchanged/worsened using the QIDS-SR item 12 during acute treatment (up to six intravenous (IV) or eight intranasal (IN) treatments) and were followed for SAED visits.
Results: Among 96 patients with SI data, 73 (76%) had baseline SI. Following acute-phase treatment, 36 (49%) achieved SI resolution, 14 (19%) partially improved, and 23 (32%) were unchanged/worsened. During the 6-month follow-up, 8 (11%) had post-acute SAED visits. While not statistically significant, patients with resolved SI had lower odds of post-acute ED visits (OR = 0.16, p = 0.12). Kaplan–Meier estimates of SAED visit-free survival across three SI change groups trended toward significance ( p = 0.066), suggesting lower cumulative healthcare (ED) utilization in more favorable change groups. Secondary analysis among 57 patients who received IV ketamine and had baseline SI showed that, after two infusions, 33 (47.2%) demonstrated a reduction in SI. Early SI improvement (⩾50% reduction in SI) was associated with a lower likelihood of any post-treatment SAED visit at 6 months after adjusting for pre-treatment SAED (OR = 0.17, 95% CI: 0.02–0.98, p = 0.047), corresponding to numbers needed to treat of 4.3.
Conclusion: Early SI changes may have prognostic implications, though larger studies are needed to confirm clinical significance.
Comparable studies
Other observational and cohort studies on esketamine for depression, most cited first.