Antidepressant and anti-suicidal effects of ketamine in treatment-resistant depression associated with psychiatric and personality comorbidities: A double-blind randomized trial

Objective: To evaluate the effects of ketamine treatment on depression and suicidal ideation in treatment resistant depression (TRD) and to determine whether they are influenced by other psychiatric and personality comorbidities.Methods: A randomized double-blind parallel-arm controlled study on 36 patients with TRD. Patients were divided into two treatment groups: ketamine (K group) and placebo (P group). Patients in the K and P groups received one infusion of medicine per week for two weeks. All participants were assessed using the Structured Interview for the Five-Factor Personality Model (SIFFM), Hamilton Depression Rating Scale (HDRS), Suicide Probability Scale (SPS), and Symptom Checklist 90 (SCL 90).Results: After treatment, there was a significant decrease in the total HDRS and SPS scores in the K group compared to the P group, but the magnitude of response was not influenced by the presence of other psychiatric symptoms. Regression model, only receive ketamine treatment was significant factor for improve suicide and depression scores.Limitations: lack of data on other outcomes that are important to patients (e.g., quality of life, cognition) and need for a larger sample size.Conclusions: Ketamine infusions in TRD reduce suicidal ideation and depression despite the presence other psychiatric and personality disorders.