Treatment-emergent psychiatric adverse events in patient-reported outcomes during ketamine use for major depressive disorder: a retrospective analysis.

Background: Treatment-resistant depression (TRD) poses a significant therapeutic challenge, with remission often unattainable. Recognition and detection of treatment-emergent adverse events (TEAEs) are essential, as these events may significantly influence the quality of treatment response. This knowledge aids in personalizing care and selecting the best treatment strategy.

Methods: In a retrospective analysis of an observational study of inpatients (n = 28) with TRD, who were administered 8 ketamine infusions as an add-on therapy, psychiatric TEAEs were assessed using the Inventory of Depressive Symptomatology Self-Report 30 (IDS SR-30) and defined as symptoms that were not present at baseline but emerged during ketamine administration. The protocol was registered at ClinicalTrials.gov on Jan 2, 2020 (NCT04226963).

Results: Sleep disturbances were the most consistently reported psychiatric TEAEs, with nighttime sleep problems increasing by the 7th infusion and persisting at follow-up (n = 5), and early waking reported across timepoints (n = 3-4). Appetite and weight changes were also observed, with both increased and decreased appetite peaking early in treatment (n = 7 and n = 6 at the 3rd infusion) and persisting at lower levels at follow-up. In contrast, mood, cognitive, and most somatic symptoms were rare (≤ 2-4 participants), and suicidal ideation was minimal (n = 1 at the 3rd infusion and follow-up).

Conclusions: This study identified sleep disturbances, appetite changes, and weight fluctuations as common patient-reported TEAEs during ketamine use for TRD inpatients. These preliminary results highlight the need for larger, controlled trials to gain a comprehensive understanding of ketamine's psychiatric safety profile.