Vagus Nerve Stimulation Modulates Inflammation in Treatment-Resistant Depression Patients: A Pilot Study

Vagal neurostimulation (VNS) is used for the treatment of epilepsy and major medical-refractory depression. VNS has neuropsychiatric functions and systemic anti-inflammatory activity. The objective of this study is to measure the clinical efficacy and impact of VNS modulation in depressive patients. Six patients with refractory depression were enrolled. Depression symptoms were assessed with the Montgomery-Asberg Depression Rating, and anxiety symptoms with the Hamilton Anxiety Rating Scale. Plasmas were harvested prospectively before the implantation of VNS (baseline) and up to 4 years or more after continuous therapy. Forty soluble molecules were measured in the plasma by multiplex assays. Following VNS, the reduction in the mean depression severity score was 59.9% and the response rate was 87%. Anxiety levels were also greatly reduced. IL-7, CXCL8, CCL2, CCL13, CCL17, CCL22, Flt-1 and VEGFc levels were significantly lowered, whereas bFGF levels were increased (p values ranging from 0.004 to 0.02). This exploratory study is the first to focus on the long-term efficacy of VNS and its consequences on inflammatory biomarkers. VNS may modulate inflammation via an increase in blood-brain barrier integrity and a reduction in inflammatory cell recruitment. This opens the door to new pathways involved in the treatment of refractory depression.

Evaluating real-world effectiveness of accelerated transcranial magnetic stimulation for treatment-resistant depression in a tertiary referral center based in Quebec, Canada

OBJECTIVE

To assess the effectiveness of accelerated transcranial magnetic stimulation (TMS) for treatment-resistant depression (TRD) in a tertiary referral center in Quebec, Canada, focusing on a real-world clinical setting.

METHODS

We reviewed the data of 247 TRD patients treated between January 2012 and May 2022 who received accelerated TMS. Participants were adults diagnosed with unipolar or bipolar depression, resistant to at least two antidepressant trials, and assessed using the Montgomery-Åsberg Depression Rating Scale (MADRS).

RESULTS

Significant symptom reduction was found in the completer sample (N = 147), with 46.3 % of patients meeting post-treatment response criteria and 36.1 % achieving remission. Baseline severity of depression, age, and the number of antidepressant trials were key predictors of treatment outcomes. Patients who did not complete treatment had generally more severe depressive and anxious symptoms and greater treatment resistance. No significant differences in response rates were observed across different TMS coils.

CONCLUSION

The study demonstrated the effectiveness and tolerability of accelerated TMS for TRD in a real-world clinical setting.

Intravenous ketamine for treatment-resistant depression patients who have failed to respond to transcranial magnetic stimulation: A case series

BACKGROUND

For individuals with treatment-resistant depression (TRD), transcranial magnetic stimulation (TMS) has become a well-established approach. In the past decade, intravenous (IV) racemic ketamine has also emerged as a potential treatment for TRD. Currently, little data is available on the clinical effects of IV racemic ketamine in TRD patients who experienced TMS-failure.

METHODS

Twenty-one (21) TRD patients who had failed to respond to a standard course of high-frequency left-dorsolateral prefrontal cortex TMS were subsequently scheduled to received IV racemic ketamine infusions. The IV racemic ketamine protocol consisted of 0,5 mg/kg infusions over 60 min, 3 times a week over 2 weeks.

RESULTS

Treatment was safe with minimal side-effects. Mean baseline MADRS score was 27.6 ± 6.4 (moderate depression), decreasing down to 18.6 ± 8.9 (mild depression) post-treatment. Mean percent improvement was 34.5 % ± 21.1 from baseline to post-treatment. Paired sample t-test showed significant MADRS score decrease pre- to post-treatment [t(20) = 7.212, p < .001]. Overall, four (4) patients (19.0 %) responded and two (2) of those achieved remission (9.5 %).

LIMITATIONS

Limitations of this case series include its retrospective and uncontrolled open-label nature, the lack of self-rating and standardized adverse events questionnaires, as well as follow-ups beyond the immediate treatment period.

CONCLUSIONS

Novel ways to increase the clinical effects of ketamine are being explored. We discuss potential combination approaches of ketamine with other modalities to augment its effects. Given the global burden of TRD, novel approaches are needed to curb the current mental health epidemic around the world.

Cardiovascular biomarkers of response to accelerated low frequency repetitive transcranial magnetic stimulation in major depression

BACKGROUND AND OBJECTIVE

Repetitive transcranial magnetic stimulation (rTMS) is an effective and safe treatment for major depressive disorder (MDD). rTMS is in need of a reliable biomarker of treatment response. High frequency (HF) dorsolateral prefrontal cortex (DLPFC) rTMS has been reported to induce significant changes in the cardiac activity of MDD patients. Low frequency DLPFC rTMS has many advantages over HF-DLPFC rTMS and thus this study aims to further investigate the effect of low frequency 1 Hz right hemisphere (R)-DLPFC rTMS on the cardiac activity of MDD patients, as well as the potential of using electrocardiogram (ECG) parameters as biomarkers of treatment outcome.

METHODS

Baseline ECG sessions were performed for 19 MDD patients. All patients then underwent 40 sessions of accelerated 1 Hz R-DLPFC rTMS one week after the baseline session.

RESULTS

Heart rate (HR) significantly decreased from the resting period to the first and third minute of the 1 Hz R-DLPFC rTMS period. Resting HR was found to have a significant negative association with treatment outcome. Prior to Bonferroni correction, HR during stimulation and the degree of rTMS-induced HR reduction were significantly negatively associated with treatment outcome. No significant changes were observed for the heart rate variability (HRV) parameters.

LIMITATIONS

Sample size (n = 19); the use of electroencephalography equipment for ECG; lack of respiration monitoring; relatively short recording duration for HRV parameters.

CONCLUSION

This novel study provides further preliminary evidence that ECG may be utilized as a biomarker of rTMS treatment response in MDD.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04376697.

Efficacy of ketamine intervention to decrease alcohol use, cravings, and withdrawal symptoms in adults with problematic alcohol use or alcohol use disorder: A systematic review and comprehensive analysis of mechanism of actions

BACKGROUND

Alcohol use disorder is highly prevalent and has important economical, societal, psychiatric, and medical consequences. All currently approved therapeutic approaches targeting alcohol dependence have relatively modest effects and high relapse rates. Recent evidence suggests that ketamine may be an effective intervention to treat alcohol use disorder and alcoholic withdrawal. This systematic review aimed to assess the current level of evidence for this intervention.

METHODS

This systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was registered on the international database of systematic reviews PROSPERO. Medline(Ovid), CINAHL Complete(EBSCOhost), PsycINFO(Ovid), EBM Reviews(Ovid), EMBASE(Ovid), and Google Scholar were searched for studies using ketamine to treat harmful alcohol use, craving, or withdrawal states in humans. Studies of any methodology that evaluated ketamine in isolation or combination with other interventions were included. The risk of bias was assessed using specific Cochrane critical appraisal tools.

RESULTS

Of 1922 abstracts identified, 8 full-text articles were eligible for inclusion, yielding a total sample size of 634 participants. Five studies investigated the impact of ketamine on alcohol use and/or cravings and/or withdrawal in outpatient settings. Three studies looked at the effect of adding ketamine to conventional treatment of withdrawal symptoms in participants admitted to intensive care unit for severe alcohol withdrawal. Results on primary outcomes were mixed within and across trials.

CONCLUSIONS

Despite promising results, the current evidence does not permit definitive conclusions about the efficacy of ketamine in alcohol use disorders or withdrawal. Future studies are warranted.

Prolonged intermittent theta burst stimulation in the treatment of major depressive disorder: a case series

Intermittent theta burst stimulation (iTBS) using 600 pulses is an effective and FDA-cleared transcranial magnetic stimulation (TMS) protocol for major depressive disorder (MDD). Prolonged iTBS (piTBS) using 1,800 pulses could increase the effectiveness of TMS for MDD, but its real-world effectiveness is still debated. We assessed the safety, tolerability, and preliminary effectiveness of a 3x daily piTBS 1,800 pulses protocol delivered over 2 weeks in 27 participants. Only four participants (18.2%) achieved response, two of them achieving remission (9.1%). Five participants (18.5%) experienced tolerability issues. Future studies should focus on the neurophysiological effects of TBS protocols to determine optimal parameters.

Transcranial magnetic stimulation and intravenous ketamine combination therapy for treatment-resistant bipolar depression: A case report

About a third of patients suffering from major depression develop treatment-resistant depression (TRD). Although repetitive transcranial magnetic stimulation (rTMS) and intravenous ketamine have proven effective for the management of TRD, many patients remain refractory to treatment. We present the case of a patient suffering from bipolar TRD. The patient was referred to us after failure to respond to first-and second-line pharmacotherapy and psychotherapy. After minimal response to both rTMS and ketamine alone, we attempted a combination rTMS and ketamine protocol, which led to complete and sustained remission. Various comparable and complimentary mechanisms of antidepressant action of ketamine and rTMS are discussed, which support further study of this combination therapy. Future research should focus on the feasibility, tolerability, and efficacy of this novel approach.

Optimized repetitive transcranial magnetic stimulation techniques for the treatment of major depression: A proof of concept study

Although effective in major depressive disorder (MDD), repetitive transcranial magnetic stimulation (rTMS) is costly and complex, limiting accessibility. To address this, we tested the feasibility of novel rTMS techniques with cost-saving opportunities, such as an open-room setting, large non-focal parabolic coils, and custom-built coil arms. We employed a low-frequency (LF) 1 Hz stimulation protocol (360 pulses per session), delivered on the most affordable FDA-approved device. MDD participants received an initial accelerated rTMS course (arTMS) of 6 sessions/day over 5 days (30 total), followed by a tapering course of daily sessions (up to 25) to decrease the odds of relapse. The self-reported Beck Depression Inventory II (BDI-II) was used to measure severity of depression. Forty-eight (48) patients completed the arTMS course. No serious adverse events occurred, and all patients reported manageable pain levels. Response and remission rates were 35.4% and 27.1% on the BDI-II, respectively, at the end of the tapering course. Repeated measures ANOVA showed significant changes of BDI-II scores over time. Even though our protocol will require further improvements, some of the concepts we introduced here could help guide the design of future trials aiming at increasing accessibility to rTMS.

Vagus Nerve Stimulation for Treatment-Resistant Depression: a Case Series of Clinical Symptoms Associated with the End of Service Period

BACKGROUND

This work describes the clinical symptoms associated with end of service (EOS) of the batteries of vagus nerve stimulation (VNS) generators in treatment-resistant depression (TRD). Because neurostimulator software may not provide reliable information on battery depletion, careful monitoring of clinical symptoms during the EOS period is an important concern in the follow-up of TRD patients treated with VNS therapy.

METHODS

Twenty-six (26) patients were implanted and followed at the Centre Hospitalier de l'Université de Montréal. Fourteen (14) patients required battery replacement and we retrieved chart data up to 3 months before generator battery replacement.

RESULTS

Our study demonstrated there might be a decrease or increase in VNS associated physical side effects, and possibly an increase in depressive symptoms during EOS.

LIMITATIONS

Our observations are limited by the retrospective nature of this small case series, and larger prospective studies evaluating both VNS side effects and depressive symptoms are therefore needed to further validate those findings.

CONCLUSION

Our study is the first to examine clinical symptoms associated with EOS of the batteries of VNS in TRD.

Repetitive transcranial magnetic stimulation for major depressive disorder: basic principles and future directions

Repetitive transcranial magnetic stimulation (rTMS) is a safe and well-tolerated intervention for major depressive disorder (MDD). Over 150 randomized controlled trials (RCTs) have been carried out, and its efficacy has been confirmed in dozens of meta-analyses. Real world data has also confirmed the effectiveness of rTMS for MDD in clinical practice, with the most recent literature indicating response rates of 40-50% and remission rates of 25-30%. In this review, we first offer an historical perspective, followed by a review of basic principles, such as putative mechanisms, procedures and protocols, stimulation targets, efficacy and durability of response, side effects, and the placebo controversy. In the second part of this review, we first discuss solutions to increase accessibility to rTMS, such as modifications to treatment equipment, protocols and setting. We continue with possible means to further increase effectiveness, such as treatment personalization and extension. We conclude by addressing the scheduling issue, with accelerated rTMS (arTMS) as a possible solution.

Specialized assertive community treatment intervention for homeless youth with first episode psychosis and substance use disorder: A 2-year follow-up study

AIM

No previous study has investigated interventions for homeless youth suffering from first episode psychosis and comorbid substance use disorder (HYPS). An intensive assertive community intervention team (IACIT) offering outreach interventions, housing support as well as integrated care for early psychosis and substance use disorder (SUD) was created in 2012 at the Centre Hospitalier de l'Université de Montréal (CHUM). To explore the impact of the addition of an IACIT to an early intervention for psychosis service (EIS) on housing stability, functional and symptomatic outcomes and mental health service use.

METHODS

A two-year longitudinal study comparing the outcome of HYPS receiving combined EIS and IACIT since 2012, to a historical cohort of HYPS receiving EIS only between 2005 and 2011. Socio-demographic data, housing stability, functioning, illness severity, SUD severity, emergency room visits and hospitalizations were assessed at admission, at 1 month, and every 3 months thereafter.

RESULTS

HYPS receiving EIS + IACIT achieved housing stability more rapidly and spent less time hospitalized than HYPS getting EIS only (RR 2.38, P = .017). HYPS with cocaine misuse were less likely to attain housing stability (RR 0.25, P = .04). No between-group differences were found for psychiatric symptoms, functioning and SUD outcomes.

CONCLUSION

The addition of IACIT-HYPS to EIS was associated with earlier housing stability and reduced total hospitalization days compared to EIS alone.

Safety and Efficacy of Accelerated Repetitive Transcranial Magnetic Stimulation Protocol in Elderly Depressed Unipolar and Bipolar Patients

OBJECTIVE

Major depressive disorder (MDD) is a prevalent condition in older adults. Although antidepressant drugs are commonly prescribed, efficacy is variable, and older patients are more prone to side effects. Repetitive transcranial magnetic stimulation (rTMS) is an alternative therapy used increasingly in the treatment of MDD. Even though recent studies have shown efficacy of rTMS in elderly depressed patients, the safety and efficacy of accelerated rTMS has not been studied in this population.

METHODS

Data were retrospectively analyzed for adults with treatment-resistant depression (N = 73, n = 19 ≥60years, n = 54 <60 years) who underwent an accelerated protocol of 30 sessions (2 sessions per day) of left dorsolateral prefrontal cortex high-frequency (20 Hz) rTMS.

RESULTS

There were statistically significant improvements in depression and anxiety symptoms from baseline to post-treatment in both age groups, but those 60years and older showed statistically greater improvement in depression and anxiety symptom scores (p = 0.01) than those less than 60. There were significantly more responders (p = 0.001) and remitters (p = 0.023) in the older group. The age groups did not differ significantly in clinical and demographic characteristics or severity of current depressive episode, although baseline anxiety was less severe in those 60years and older. Unipolar and bipolar patients had a similar clinical response, and treatment appeared to be well tolerated by all patients.

CONCLUSION

Our results suggest that accelerated rTMS protocol is a safe and effective treatment for unipolar and bipolar depressed subjects, including older adults.

Differential modulation of descending signals from the reticulospinal system during reaching and locomotion

We tested the hypothesis that the same spinal interneuronal pathways are activated by the reticulospinal system during locomotion and reaching. If such were the case, we expected that microstimulation within the pontomedullary reticular formation (PMRF) would evoke qualitatively similar responses in muscles active during both behaviors. To test this, we stimulated in 47 sites within the PMRF during both tasks. Stimulation during locomotion always produced a strongly phase-dependent, bilateral pattern of activity in which activity in muscles was generally facilitated or suppressed during one phase of activity (swing or stance) and was unaffected in the other. During reaching, stimulation generally activated the same muscles as during locomotion, although the modulation of the magnitude of the evoked responses was less limb dependent than during locomotion. An exception was found for some forelimb flexor muscles that were strongly facilitated by stimulation during the swing phase of locomotion but were not influenced by stimulation during the transport phase of the reach. We suggest that during locomotion the activity in interneuronal pathways mediating signals from the reticulospinal system is subject to strong modulation by the central pattern generator for locomotion. During reach, we suggest that, for most muscles, the same spinal interneuronal pathways are used to modify muscle activity but are not as strongly gated according to limb use as during locomotion. Finally, we propose that the command for movement during discrete voluntary movements suppresses the influence of the reticulospinal system on selected forelimb flexor muscles, possibly to enhance fractionated control of movement.