Structural connectivity and response to ketamine therapy in major depression: A preliminary study.
Megha M Vasavada, Amber M Leaver, Randall Espinoza, Shantanu Joshi, Stephanie N Njau, Roger P Woods, Katherine L Narr
Journal of Affective Disorders January 15, 2016 DOI: 10.1016/j.jad.2015.11.018 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 10 |
| Population | Patients with major depressive disorder |
| Intervention | Ketamine |
| Duration | 24-hour post-infusion |
| Topics | Depression Esketamine Ketamine |
| Keywords | Biomarkers Fractional anisotropy fa Glutamate Treatment response |
| Citations | 58 |
| Key findings | Greater fractional anisotropy in the cingulum and forceps minor before ketamine infusion was associated with clinical response 24 hours later, while non-responders showed reduced white matter integrity in these pathways compared to healthy controls. |
Abstract
Ketamine elicits an acute antidepressant effect in patients with major depressive disorder (MDD). Here, we used diffusion imaging to explore whether regional differences in white matter microstructure prior to treatment may predict clinical response 24h following ketamine infusion in 10 MDD patients. FSL's Tract-Based Spatial Statistics (TBSS) established voxel-level differences in fractional anisotropy (FA) between responders (patients showing >50% improvement in symptoms 24h post-infusion) and non-responders in major white matter pathways. Follow-up regions-of-interest (ROI) analyses examined differences in FA and radial (RD), axial (AD) and mean diffusivity (MD) between responders and non-responders and 15 age- and sex-matched controls, with groups compared pairwise. Whole brain TBSS (p<0.05, corrected) and confirmatory tract-based regions-of-interest analyses showed larger FA values in the cingulum and forceps minor in responders compared to non-responders; complementary decreases in RD occurred in the cingulum (p<0.05). Only non-responders differed from controls showing decreased FA in the forceps minor, increased RD in the cingulum and forceps minor, and increased MD in the forceps minor (p<0.05). Non-responders showed an earlier age of onset and longer current depressive episode than responders. Though these factors did not interact with diffusion metrics, results may be impacted by the limited sample size. Though findings are considered preliminary, significant differences in FA, RD and MD shown in non-responders compared to responders and controls in fronto-limbic and ventral striatal pathways suggest that the structural architecture of specific functional networks mediating emotion may predict ketamine response in MDD.
Comparable studies
Other observational and cohort studies on ketamine for depression, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Concomitant BDNF and sleep slow wave changes indicate ketamine-induced plasticity in major depressive disorder Patients with treatment-resistant major depressive disorder | 2012 | Observational cohort | n = 30 |
| Altered peripheral immune profiles in treatment-resistant depression: response to ketamine and prediction of treatment outcome Healthy controls and actively depressed patients with treatment-resistant depression... | 2017 | Observational cohort | n = 59 |
| Clinical Predictors of Ketamine Response in Treatment-Resistant Major Depression Treatment-resistant inpatients with DSM-IV-TR-diagnosed major depressive disorder or... | 2014 | Post hoc analysis of pooled data from four studies | n = 108 |
| An investigation of amino-acid neurotransmitters as potential predictors of clinical improvement to ketamine in depression Drug-free patients with major depressive disorder | 2011 | Observational cohort | n = 14 |
| Efficacy of ketamine therapy in the treatment of depression Drug-free/naïve men with severe depression, no history of psychotic disorder, head... | 2019 | Observational cohort | n = 25 |