OPEN Foundation

Menu
Search
Close this search box.

N. Brutsche

Features of dissociation differentially predict antidepressant response to ketamine in treatment-resistant depression

February 17, 2018 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

BACKGROUND:
Ketamine induces rapid and robust antidepressant effects, and many patients also describe dissociation, which is associated with antidepressant response. This follow-up study investigated whether antidepressant efficacy is uniquely related to dissociative symptom clusters.
METHODS:
Treatment-resistant patients with major depressive disorder (MDD) or bipolar disorder (BD) (n = 126) drawn from three studies received a single subanesthetic (0.5 mg/kg) ketamine infusion. Dissociative effects were measured using the Clinician-Administered Dissociative States Scale (CADSS). Antidepressant response was measured using the 17-item Hamilton Depression Rating Scale (HAM-D). A confirmatory factor analysis established the validity of CADSS subscales (derealization, depersonalization, amnesia), and a general linear model with repeated measures was fitted to test whether subscale scores were associated with antidepressant response.
RESULTS:
Factor validity was supported, with a root mean square error of approximation of .06, a comparative fit index of .97, and a Tucker-Lewis index of .96. Across all studies and timepoints, the depersonalization subscale was positively related to HAM-D percent change. A significant effect of derealization on HAM-D percent change was observed at one timepoint (Day 7) in one study. The amnesia subscale was unrelated to HAM-D percent change.
LIMITATIONS:
Possible inadequate blinding; combined MDD/BD datasets might have underrepresented ketamine’s antidepressant efficacy; the possibility of Type I errors in secondary analyses.
CONCLUSIONS:
From a psychometric perspective, researchers may elect to administer only the CADSS depersonalization subscale, given that it was most closely related to antidepressant response. From a neurobiological perspective, mechanistic similarities may exist between ketamine-induced depersonalization and antidepressant response, although off-target effects cannot be excluded.
Niciu, M. J., Shovestul, B. J., Jaso, B. A., Farmer, C., Luckenbaugh, D. A., Brutsche, N. E., … & Zarate, C. A. (2018). Features of dissociation differentially predict antidepressant response to ketamine in treatment-resistant depression. Journal of affective disorders, 232, 310-315. 10.1016/j.jad.2018.02.049
Link to full text

Assessing measures of suicidal ideation in clinical trials with a rapid-acting antidepressant

June 16, 2015 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Rapid reduction of suicidal thoughts is critical for treating suicidal patients. Clinical trials evaluating these treatments require appropriate measurement. Key methodological issues include: 1) the use of single or multi-item assessments, and 2) evaluating whether suicidal ideation measures can track rapid change over time. The current study presents data from two randomized, placebo-controlled, crossover clinical trials evaluating ketamine in individuals with treatment-resistant depression (n = 60). Participants were assessed for suicidal thoughts using the Hamilton Depression Rating Scale (HAM-D), Montgomery-Asberg Depression Rating Scale (MADRS), Beck Depression Inventory (BDI), and Scale for Suicidal Ideation (SSI) at eight time points over three days. Assessments were compared using correlational analyses and effect sizes at 230 min and three days after ketamine infusion. Linear mixed models evaluated change in ideation across all time points. The HAM-D and MADRS suicide items demonstrated correlations of r > .80 with the first five items of the SSI (SSI5). On linear mixed models, an effect for ketamine was found for the HAM-D, MADRS, BDI items, and SSI5 (p < .001), but not for the full SSI (p = .88), which suggests a limited ability to assess change over time in patients with low levels of suicidal thoughts. Taken together, the results suggest that repeated suicidal assessments over minutes to days appear to detect improvement in suicidal thoughts after ketamine infusion compared to placebo. The MADRS suicide item, BDI suicide item, and SSI5 may be particularly sensitive to rapid changes in suicidal thoughts.

Ballard, E. D., Luckenbaugh, D. A., Richards, E. M., Walls, T. L., Brutsché, N. E., Ameli, R., … & Zarate, C. A. (2015). Assessing measures of suicidal ideation in clinical trials with a rapid-acting antidepressant. Journal of psychiatric research, 68, 68-73. dx.doi.org/10.1016/j.jpsychires.2015.06.003
Link to full text

Do the dissociative side effects of ketamine mediate its antidepressant effects?

February 18, 2014 / Depressive Disorders, Ketamine, Neuroscience, Papers, Psychiatry & Medicine, Psychology, Publications / By / , , , , , , ,

Abstract

Background

The N-methyl-d-aspartate receptor antagonist ketamine has rapid antidepressant effects in major depression. Psychotomimetic symptoms, dissociation and hemodynamic changes are known side effects of ketamine, but it is unclear if these side effects relate to its antidepressant efficacy.

Methods

Data from 108 treatment-resistant inpatients meeting criteria for major depressive disorder and bipolar disorder who received a single subanesthetic ketamine infusion were analyzed. Pearson correlations were performed to examine potential associations between rapid changes in dissociation and psychotomimesis with the Clinician-Administered Dissociative States Scale (CADSS) and Brief Psychiatric Rating Scale (BPRS), respectively, manic symptoms with Young Mania Rating Scale (YMRS), and vital sign changes, with percent change in the 17-item Hamilton Depression Rating scale (HDRS) at 40 and 230 min and Days 1 and 7.

Results

Pearson correlations showed significant association between increased CADSS score at 40 min and percent improvement with ketamine in HDRS at 230 min (r=−0.35, p=0.007) and Day 7 (r=−0.41, p=0.01). Changes in YMRS or BPRS Positive Symptom score at 40 min were not significantly correlated with percent HDRS improvement at any time point with ketamine. Changes in systolic blood pressure, diastolic blood pressure, and pulse were also not significantly related to HDRS change.

Limitations

Secondary data analysis, combined diagnostic groups, potential unblinding.

Conclusions

Among the examined mediators of ketamine׳s antidepressant response, only dissociative side effects predicted a more robust and sustained antidepressant. Prospective, mechanistic investigations are critically needed to understand why intra-infusion dissociation correlates with a more robust antidepressant efficacy of ketamine.

Luckenbaugh, D. A., Niciu, M. J., Ionescu, D. F., Nolan, N. M., Richards, E. M., Brutsche, N. E., … & Zarate, C. A. (2014). Do the dissociative side effects of ketamine mediate its antidepressant effects?. Journal of affective disorders, 159, 56-61. http://dx.doi.org/10.1016/j.jad.2014.02.017

Link to full text

Replication of Ketamine's Antidepressant Efficacy in Bipolar Depression: A Randomized Controlled Add-On Trial

January 31, 2012 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Background

Currently, no pharmacological treatments for bipolar depression exist that exert rapid (within hours) antidepressant or antisuicidal effects. We previously reported that intravenous administration of the N-methyl-D-aspartate antagonist ketamine produced rapid antidepressant effects in patients with treatment-resistant bipolar depression. The present study sought to replicate this finding in an independent sample.

Methods

In this double-blind, randomized, crossover, placebo-controlled study, 15 subjects with DSM-IV bipolar I or II depression maintained on therapeutic levels of lithium or valproate received a single intravenous infusion of either ketamine hydrochloride (.5 mg/kg) or placebo on 2 test days 2 weeks apart. The primary outcome measure was the Montgomery-Asberg Depression Rating Scale, which was used to rate overall depressive symptoms at baseline; at 40, 80, 110, and 230 minutes postinfusion; and on days 1, 2, 3, 7, 10, and 14 postinfusion.

Results

Within 40 minutes, depressive symptoms, as well as suicidal ideation, significantly improved in subjects receiving ketamine compared with placebo (d = .89, 95% confidence interval = .61–1.16, and .98, 95% confidence interval = .64–1.33, respectively); this improvement remained significant through day 3. Seventy-nine percent of subjects responded to ketamine and 0% responded to placebo at some point during the trial. The most common side effect was dissociative symptoms, which occurred only at the 40-minute time point.

Conclusion

This study replicated our previous finding that patients with bipolar depression who received a single ketamine infusion experienced a rapid and robust antidepressant response. In addition, we found that ketamine rapidly improved suicidal ideation in these patients.

Zarate Jr., A., Brutsche, N. E., Ibrahim, L., Franco-Chaves, J., Diazgranados, N., Cravchik, A., … Luckenbaugh, D. A. (2011). Replication of Ketamine’s Antidepressant Efficacy in Bipolar Depression: A Randomized Controlled Add-On Trial. Biological Psychiatry, 71(11), 939-946. http://dx.doi.org/10.1016/j.biopsych.2011.12.010
Link to full text

A Randomized Add-on Trial of an N-methyl-D-aspartate Antagonist in Treatment-Resistant Bipolar Depression

August 9, 2010 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Context: Existing therapies for bipolar depression have a considerable lag of onset of action. Pharmacological strategies that produce rapid antidepressant effects—for instance, within a few hours or days—would have an enormous impact on patient care and public health.

Objective: To determine whether an N-methyl-Daspartate–receptor antagonist produces rapid antidepressant effects in subjects with bipolar depression.

Design: A randomized, placebo-controlled, doubleblind, crossover, add-on study conducted from October 2006 to June 2009.

Setting: Mood Disorders Research Unit at the National Institute of Mental Health, Bethesda, Maryland.

Patients: Eighteen subjects with DSM-IV bipolar depression (treatment-resistant).

Interventions: Subjects maintained at therapeutic levels of lithium or valproate received an intravenous infusion of either ketamine hydrochloride (0.5 mg/kg) or placebo on 2 test days 2 weeks apart. The Montgomery- Asberg Depression Rating Scale was used to rate subjects at baseline and at 40, 80, 110, and 230 minutes and on days 1, 2, 3, 7, 10, and 14 postinfusion.

Results: Within 40 minutes, depressive symptoms significantly improved in subjects receiving ketamine compared with placebo (d=0.52, 95% confidence interval [CI], 0.28-0.76); this improvement remained significant through day 3. The drug difference effect size was largest at day 2 (d=0.80, 95% CI, 0.55-1.04). Seventy-one percent of subjects responded to ketamine and 6% responded to placebo at some point during the trial. One subject receiving ketamine and 1 receiving placebo developed manic symptoms. Ketamine was generally well tolerated; the most common adverse effect was dissociative symptoms, only at the 40-minute point.

Diazgranados, N.,  Ibrahim, L. Brutsche, N. E., Newberg, A., Kronstein, P.,  Khalife, S., … Zarate Jr., Z. A. (2010). A Randomized Add-on Trial of an N-methyl-D-aspartate Antagonist in Treatment-Resistant Bipolar Depression. Archives of General Psychiatry, 67(8). http://dx.doi.org/10.1001/archgenpsychiatry.2010.90
Link to full text

interested in becoming a trained psychedelic-assisted therapist?

Management of Psychedelic-Related Complications - Online Event - Nov 20th

REGISTER NOW