Baseline monocyte count predicts symptom improvement during intravenous ketamine therapy in treatment-resistant depression: a single-arm open-label observational study

• DOI: 10.3389/fpsyt.2024.1415505
• Publication Date: 2024-06-24T04:45:47Z
• Authors: Bruno Pedraz-Petr...; Moritz Spangemacher; Anton Deicher; Lena Drews; Julie Defert; Ana Yaiza Silva-C...; Paul Wein; Elena Riedinger; Gerhard Gründer; Maria Gilles; Alexander Sartorius; Jonathan R. Reinwald
• Keywords: Depression

Background Neuroinflammatory processes in depression are associated with treatment resistance to conventional antidepressants. Ketamine is an effective new therapeutic option for treatment-resistant (TRD). Its well-established immunomodulatory properties hypothesized mediate its antidepressant effect. In this context, higher levels of inflammation may predict a better response. However, conclusive evidence hypothesis lacking. We thus investigated whether standard peripheral inflammatory cell markers and C-reactive protein (CRP) could symptom improvement during intravenous ketamine therapy TRD patients. Methods 27 participants were treated six weight-adjusted infusions (0.5 mg/kg bodyweight) over three weeks. Baseline assessments included CRP, absolute monocyte count (AMC), neutrophil (ANC). Depression severity was measured using the Montgomery-Åsberg Rating Scale (MADRS) at baseline (D 1 ), after first 3 ) before last infusion 18 ). Raters blinded laboratory assessments. Results 13 responded treatment, 8 partially responded. AMC showed strong negative correlation MADRS change D (r=-0.57, p=0.002) (r =-0.48, p=0.010), indicating that high greater improvement. A generalized linear model confirmed association when additionally accounting age, sex, body mass index. Specifically, demonstrated predictive value discriminate responders partial from non-responders, but lacked discriminative ability between responders. ANC correlated changes (r=-0.39, p=0.046), while CRP values did not correlate all. Conclusions Our prospective single-arm open-label observational study reliably predicted therefore serve as simple easily accessible marker daily clinical practice. Future studies larger sample sizes more detailed longitudinal assessment subtypes needed understand specific relationship monocytes neuromodulatory effects ketamine.