Ketamine-Induced Mania During Treatment for Complex Regional Pain Syndrome

Ketamine and chronic treatment-resistant depression: real-world practice and after relapse

BACKGROUND

Chronic treatment-resistant depression (TRD) poses a major challenge for clinicians. Ketamine has shown a rapid but short-lived antidepressant effect in several studies involving TRD patients with different demographic and clinical profiles. Our study aimed to assess the antidepressant effect of serial infusion sessions of ketamine in patients with chronic TRD and evaluate the severity of symptoms after relapse and the general psychiatric health of the responding patients.

METHODS

In this single arm open-label study, six infusions of ketamine at 0.5 mg/kg were administered to chronic TRD patients for approximately two weeks. Response and remission rates, side effects, adverse events and after-relapse symptoms were evaluated, and patients were followed for three months.

RESULTS

23 patients underwent at least one infusion session, and 18 patients completed the six sessions. Twelve (66.67%) patients responded to the treatment at some point, and 11 (61.11%) patients maintained response after the end of the treatment protocol. One infusion was not sufficient to achieve a response (P > 0.9999, z = 1.81), and more than half of the responders met the response criteria after the third infusion. Only one patient (5.56%) achieved remission at the end of the infusion phase. All but one ketamine responders relapsed within one month after the end of the treatment. There was no statistical difference between baseline and after-relapse MADRS scores (P = 0.7886, 95% CI=-5.512-4.312, R2 = 0,008411). However, a high incidence of serious adverse events related to suicidality was evident; one of the non-responding patients attempted suicide and several attempts to sedate this patient with benzodiazepines failed. Two responding patients ended up with a suicidal attempt or severe suicidal thoughts.

CONCLUSIONS

Introducing rapid-acting antidepressant to manage TRD patients in clinical practice demands further investigation, and the benefit-to-harm ratio should be assessed in the light of the increased risk of suicidality.

Chronic lithium treatment ameliorates ketamine-induced mania-like behavior via the PI3K-AKT signaling pathway

Ketamine, a rapid-acting antidepressant drug, has been used to treat major depressive disorder and bipolar disorder (BD). Recent studies have shown that ketamine may increase the potential risk of treatment-induced mania in patients. Ketamine has also been applied to establish animal models of mania. At present, however, the underlying mechanism is still unclear. In the current study, we found that chronic lithium exposure attenuated ketamine-induced mania-like behavior and c-Fos expression in the medial prefrontal cortex (mPFC) of adult male mice. Transcriptome sequencing was performed to determine the effect of lithium administration on the transcriptome of the PFC in ketamine-treated mice, showing inactivation of the phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) signaling pathway. Pharmacological inhibition of AKT signaling by MK2206 (40 mg/kg), a selective AKT inhibitor, reversed ketamine-induced mania. Furthermore, selective knockdown of AKT via AAV-AKT-shRNA-EGFP in the mPFC also reversed ketamine-induced mania-like behavior. Importantly, pharmacological activation of AKT signaling by SC79 (40 mg/kg), an AKT activator, contributed to mania in low-dose ketamine-treated mice. Inhibition of PI3K signaling by LY294002 (25 mg/kg), a specific PI3K inhibitor, reversed the mania-like behavior in ketamine-treated mice. However, pharmacological inhibition of mammalian target of rapamycin (mTOR) signaling with rapamycin (10 mg/kg), a specific mTOR inhibitor, had no effect on ketamine-induced mania-like behavior. These results suggest that chronic lithium treatment ameliorates ketamine-induced mania-like behavior via the PI3K-AKT signaling pathway, which may be a novel target for the development of BD treatment.

Efficacy of ketamine for comorbid depression and acute or chronic pain: A systematic review

Pain and depression frequently co-occur. Due to its antidepressant and analgesic properties, ketamine has been used for the management of treatment-resistant depression and pain. This systematic review examined the literature on the efficacy of sub-anesthetic doses of ketamine in individuals experiencing comorbid depression and chronic pain (CDCP), as well as comorbid depression and acute pain (CDAP). A secondary objective was to provide an assessment of dosage, route, and adverse effects of ketamine treatment for CDCP and CDAP. A literature search was conducted on MEDLINE, PsycINFO, and Embase databases, coupled with a manual screening of the bibliography sections of included articles. In addition, registered ongoing and planned trials were searched on Clinicaltrials.gov. The end date of the search was April 9th, 2022. Included studies assessed changes in depression and pain in patients receiving at least one sub-anesthetic dose of ketamine. Assessment of quality was conducted using the GRADE checklist. Of the 7 CDCP clinical trials, 3 reported a reduction in depression and pain, 3 reported a reduction in depression or pain only, and 1 reported no improvement in either comorbidity. Among the 7 CDAP clinical trials, 4 studies found improvements in depression and pain while the remaining 3 reported improvements in only one parameter. Ten of the 12 case studies and 2 of the 3 observational studies assessing CDCP and CDAP found improvements in pain and depression scores post-treatment with effects of variable duration. The planned methodologies of the registered clinical trials are in line with those of the published research. Preliminary evidence supports the efficacy of ketamine in treating CDCP and CDAP. However, the current review identified a small number of heterogeneous studies with mixed results, preventing comprehensive conclusions. More longitudinal placebo-controlled studies are needed to identify the effects of ketamine for patients with CDCP and CDAP.

Chronic lithium exposure attenuates ketamine-induced mania-like behavior and c-Fos expression in the forebrain of mice

Ketamine, a dissociative anaesthetic, has been used in the treatment of major depressive disorder (MDD) as a rapid acting antidepressant drug. Recent studies have shown that ketamine may increase the potential risk of treatment-induced mania in MDD patients. Lithium is a well-known mood stabilizer and has been widely used for the treatment of mania. It is not fully understood which forebrain regions are involved in ketamine- and lithium-induced expression of c-Fos. Therefore, our aim was to investigate the effect of chronic lithium treatment on mania-like behavior and c-Fos expression in the mouse forebrain activated by a single administration of ketamine. In the open field test, our results showed that ketamine significantly increased the total distance and total cumulative duration of movement in mice, while chronic lithium could attenuate these effects of ketamine. In addition, acute ketamine induced higher c-Fos expression in the lateral septal nucleus, hypothalamus, amygdala, and hippocampus of mice in the treatment group compared to those in the control group. However, chronic lithium inhibited the significant increase in c-Fos-immunoreactive neurons following acute ketamine administration in the dentate gyrus of the hippocampus, field CA1 of the hippocampus, dorsal subiculum, ventral subiculum, ventral subiculum, central amygdaloid nucleus and basolateral amygdaloid nucleus. In summary, our research shows that pretreatment with lithium moderates the effects of acute ketamine administration on mania-like behavior and c-Fos expression in the forebrain. These findings could be helpful in better understanding the episodes of mania related to ketamine treatment for MDD and bipolar disorder.

Affective Switch Associated With Oral, Low Dose Ketamine Treatment in a Patient With Treatment Resistant Bipolar I Depression. Case Report and Literature Review

There is a growing evidence for the rapid and robust antidepressive effect of ketamine in unipolar and bipolar treatment resistant depression although evidence for the risk of affective switch is still limited. This case presents bipolar I disorder patient with treatment resistant depressive episode experiencing a switch to manic episode with mixed features shortly after receiving eight subanaesthetic doses of oral ketamine as an add-on treatment preceded by 2-day period of manic symptoms.