Augmentation Therapy With Serial Intravenous Ketamine Over 18 Months in a Patient With Treatment Resistant Depression

Case report: Medical student types journals during ketamine infusions for suicidal ideation, treatment-resistant depression, post-traumatic stress disorder, and generalized anxiety disorder

Suicide is the most common cause of death in male resident physicians and the second most common cause of death in resident physicians overall. Physicians also experience high rates of major depressive disorder (MDD), post-traumatic stress disorder (PTSD), and burnout. These conditions frequently develop during medical school, and threaten not only physicians but the patients they care for. A 30-year-old medical student presented to our clinic with a history of treatment-resistant depression (TRD), generalized anxiety disorder (GAD), PTSD, and 5 years of daily suicidal ideation. Previous treatments included therapy, lifestyle modifications, and various combinations of six antidepressants. These interventions had little effect on the patient's mental health. The patient was treated at our clinic with an 8-month regimen of IV ketamine infusions and ketamine-assisted psychotherapy (KAP). The patient achieved remission from suicidality and PTSD within 1 month; and TRD and GAD within 7 months. The patient's Patient Health Questionnaire (PHQ-9) score decreased from 25 (severe depression) to 1 (not depressed). These findings suggest that ketamine and KAP may represent effective interventions for mental health applications in healthcare professionals. The patient made the unique decision to attempt to type narrative journals during four of his ketamine infusions (doses ranged from 1.8 to 2.1 mg/kg/h IV). The patient successfully typed detailed journals throughout each 1-h ketamine infusion. To our knowledge, these journals represent the first independently typed, first-person, real-time narratives of ketamine-induced non ordinary states of consciousness. The transcripts of these journals may provide useful insights for clinicians, particularly in the context of KAP.

Real-world effectiveness of ketamine in treatment-resistant depression: A systematic review & meta-analysis

Ketamine is a promising therapeutic option in treatment-resistant depression (TRD). The acute efficacy of ketamine in TRD has been demonstrated in replicated randomised-controlled trials (RCTs), but the generalizability of RCT data to real-world practice is limited. To this end, we conducted a systematic review (Search date: 25/12/2021; 1482 records identified) and meta-analysis of studies evaluating the real-world clinical effectiveness of ketamine in TRD patients. Four overlapping syntheses (Total n = 2665 patients; k = 79 studies) and 32 meta-regressions (Total n = 2050; k = 37) were conducted. All results suggest that the mean antidepressant effect is substantial (mean ± 95% CI, % responded = 45 ± 10%; p< 0.0001, % remitted = 30 ± 5.9%; p< 0.0001, Hedges g of symptomatological improvement = 1.44 ± 0.609; p < 0.0001), but the effect varies considerably among patients. The more treatment-resistant cases were found to remit less often (p < 0.01), but no such effect on response was evident (p > 0.05). Meta-regressions also confirmed that the therapeutic effect does not significantly decline with repeated treatments (p > 0.05). These results demonstrate that even the most treatment-resistant patients may benefit from ketamine, and that mid-to-long term treatment is effective in many patients.

Intravenous Ketamine for Adolescents with Treatment-Resistant Depression: An Open-Label Study

BACKGROUND

Novel interventions for treatment-resistant depression (TRD) in adolescents are urgently needed. Ketamine has been studied in adults with TRD, but little information is available for adolescents. This study investigated efficacy and tolerability of intravenous ketamine in adolescents with TRD, and explored clinical response predictors.

METHODS

Adolescents, 12-18 years of age, with TRD (failure to respond to two previous antidepressant trials) were administered six ketamine (0.5 mg/kg) infusions over 2 weeks. Clinical response was defined as a 50% decrease in Children's Depression Rating Scale-Revised (CDRS-R); remission was CDRS-R score ≤28. Tolerability assessment included monitoring vital signs and dissociative symptoms using the Clinician-Administered Dissociative States Scale (CADSS).

RESULTS

Thirteen participants (mean age 16.9 years, range 14.5-18.8 years, eight biologically male) completed the protocol. Average decrease in CDRS-R was 42.5% (p = 0.0004). Five (38%) adolescents met criteria for clinical response. Three responders showed sustained remission at 6-week follow-up; relapse occurred within 2 weeks for the other two responders. Ketamine infusions were generally well tolerated; dissociative symptoms and hemodynamic symptoms were transient. Higher dose was a significant predictor of treatment response.

CONCLUSIONS

These results demonstrate the potential role for ketamine in treating adolescents with TRD. Limitations include the open-label design and small sample; future research addressing these issues are needed to confirm these results. Additionally, evidence suggested a dose-response relationship; future studies are needed to optimize dose. Finally, questions remain regarding the long-term safety of ketamine as a depression treatment; more information is needed before broader clinical use.

Maintenance Ketamine Therapy for Treatment-Resistant Depression

BACKGROUND

Previous studies have demonstrated ketamine to have a rapid antidepressant effect in some patients with treatment-resistant depression (TRD), but the effect is unfortunately not sustained in the long term. In this study, we report on the clinical use of ongoing maintenance ketamine infusions in a group of patients with TRD, beyond an acute course of 6 to 8 ketamine infusions.

METHODS

This retrospective case series reports on 11 patients with TRD who received maintenance ketamine infusions, defined as treatments beyond an initial series of up to 8 infusions. Charts were reviewed to collect data on response to treatment and side effects.

RESULTS

All 11 patients in this case series were noted to have a reduction in their Beck Depression Inventory II (BDI-II) score after an acute course of treatment and a lower median BDI-II during their maintenance treatments than their baseline BDI-II. At the study end point, 4 patients were continuing maintenance ketamine and 1 patient had transitioned to maintenance intranasal ketamine. Four patients discontinued ketamine due to loss of effect and 1 due to side effects, and the reason for discontinuation was not noted for the remaining 2 patients. No major adverse events were noted in these patients receiving maintenance treatments, and it was well tolerated overall.

CONCLUSIONS

Maintenance ketamine treatments may be an effective way of maintaining treatment response in some ketamine responders. Future research is required to determine optimal length of treatment in those who respond to ketamine and to track adverse effects over a longer time.

Is Ketamine the Future Clozapine for Depression? A Case Series and Literature Review on Maintenance Ketamine in Treatment-resistant Depression With Suicidal Behavior

Ketamine has shown effectiveness as a rapid-acting antidepressant with antisuicidal effects in terms of reduction of suicidal ideation in the short term. However, the evidence for long-term maintenance ketamine therapy for treatment-resistant depression (TRD) and suicidal behavior is limited. This case series (N=13) highlights the role of adjunctive serial maintenance ketamine infusions in restoring functionality in treatment-resistant unipolar and bipolar (mixed) depression with significant suicide risk and multiple comorbidities, including alcohol dependence. Two cases of TRD achieved functional remission with long-term maintenance ketamine treatment. The first case illustrates the potential synergistic interaction between ketamine and lamotrigine to achieve a sustained antidepressant response in the patient for 7 months. The second case may possibly be the longest reported case of maintenance ketamine therapy, with treatment continuing for 5 years to date. Ketamine treatment showed acute effectiveness in another 7 cases, especially in terms of reduction of suicidal ideation, albeit without significant long-term antidepressant effect. Factors that may contribute to lack of effectiveness of serial ketamine include inadequate mood stabilization in TRD in bipolar spectrum diagnoses, concomitant benzodiazepine use, complex comorbidities, and adverse effects such as significant hypertension and severe dissociation. Future systematic controlled studies are warranted to establish the efficacy and safety profile of long-term ketamine as maintenance therapy for TRD with suicidal behavior.

Side-effects associated with ketamine use in depression: a systematic review

This is the first systematic review of the safety of ketamine in the treatment of depression after single and repeated doses. We searched MEDLINE, PubMed, PsycINFO, and Cochrane Databases and identified 288 articles, 60 of which met the inclusion criteria. After acute dosing, psychiatric, psychotomimetic, cardiovascular, neurological, and other side-effects were more frequently reported after ketamine treatment than after placebo in patients with depresssion. Our findings suggest a selective reporting bias with limited assessment of long-term use and safety and after repeated dosing, despite these being reported in other patient groups exposed to ketamine (eg, those with chronic pain) and in recreational users. We recommend large-scale clinical trials that include multiple doses of ketamine and long-term follow up to assess the safety of long-term regular use.

Ketamine enantiomers in the rapid and sustained antidepressant effects

Recent evidence has suggested that the N-methyl-D-aspartate receptor antagonist ketamine shows significant therapeutic effects in major depression and bipolar disorder. This effect is especially important in treatment-resistant depression and depression with suicidal ideation. In this review we explain the mechanism of action, drug efficacy, and the side effects of ketamine; the antidepressive effects of ketamine; the individual effects of ketamine isomers, R(-) ketamine and S(+) ketamine; the effects of the combination of ketamine with electroconvulsive therapy; and the possible use of ketamine in treating depression.

[Research progress of depression and the application of esketamine]

The pathogenesis and etiology of still remain unknown. Current evidence suggests that the occurrence of depression may be related to a reduced secretion of neurotransmitters, neuronal apoptosis, inflammation, intestinal flora and other factors. Although the commonly used antidepressants such as SSRIs, SNRIs, NaSSA, and SARIs produce some therapeutic effects, they fail to relieve the full spectrum of the symptoms of depression. In recent years, esketamine was found to produce a potent and a long-lasting antidepressant effect by acting on the NMDA receptors. Herein the authors review the progress in the study of the pathogenesis and drug therapies of depression, the efficacy of esketamine treatment and the underlying mechanism, and the prospect of esketamine treatment. Currently the mechanism of the antidepressant effect of esketamine remains indeterminate and its clinical application is limited, but its effect in rapidly alleviating the symptoms of depression suggests its bright prospect for clinical applications.