Background and objectives: There is evidence for ketamine use in treatment-resistant depression (TRD). Several safety concerns arise regarding adverse drug reactions and specific subpopulations. The aim of this paper is to investigate the safety of intravenous ketamine treatment concerning dissociative and psychotic measures in TRD inpatients with Major Depressive Disorder (MDD) and Bipolar depression (BP) with somatic comorbidities.
Methods: The study population of forty-nine inpatients comprises of MDD and BP subjects treated with ketamine registered in the naturalistic observational protocol of the tertiary reference unit for mood disorders (NCT04226963). This dataset represents an intermittent analysis of an observational study performed for interim modelling of observational learning. The study may be underpowered due to the small sample size. The observations apply to the inhomogeneous TRD population in a single-site with no blinding and are limited to the acute administration.
Results: The epilepsy was significantly associated with changes in BPRS over time (p=0.008). Psychotic symptomatology with BPRS scores for comorbid somatic conditions excluding epilepsy turned out to be insignificant (p = 0.198) regardless of the diagnosis. However, for a subgroup of patients with epilepsy substantial fluctuation was seen across all administrations in the time course of the study.
Conclusions: In ketamine use, careful consideration of comorbidities and concomitant medication is needed. In ketamine administration, close-clinical supervision is necessary at every visit. Psychotic symptoms must be taken into consideration in planning treatment with TRD patients with epilepsy. Somatic comorbidity may impact dissociative symptomatology.
Trial Registration: Study registered: 04DEC2019, clinicaltrials.com no. NCT04226963 https://clinicaltrials.gov/ct2/show/NCT04226963