Management of Treatment-Resistant Depression: Challenges and Strategies

Comparison of overall survival and healthcare resource utilization among patients with major depressive disorder with or without psychiatric emergency admission: A real-world study from Hungary

BACKGROUND

Patients with major depressive disorder (MDD) hospitalized for psychiatric emergencies (PE) represent a high-risk population, requiring immediate intervention. Overall survival and healthcare resource utilization were evaluated among MDD patients with PE (MDD-PE) vs without PE (MDD-nonPE) using data from the Hungarian National Health Insurance Fund database (2009 to 2020).

METHODS

Patients with MDD were selected if they had at least (i) 2 records of MDD diagnosis, or (ii) 1 record of MDD diagnosis and 1 prescription of antidepressant within 90 days of each other between 01 January 2010 and 31 December 2020. MDD-PE patients should have an inpatient hospitalization in a psychiatric ward dedicated for acute treatment, and/or a visit to an emergency department with ≥1 psychiatric and/or suicidal condition among the discharge diagnoses. Patients in the MDD-PE and MDD-nonPE cohorts were matched using a 1:1 propensity score matching algorithm based on age, gender, location of residence, and selected pre-index comorbidities.

RESULTS

28,988 MDD-PE and 28,988 MDD-nonPE patients were included after propensity score matching. Overall survival was significantly shorter among MDD-PE vs matched MDD-nonPE patients (HR: 1.40, 95%CI: 1.33-1.48; p < 0.001). MDD-PE (vs matched MDD-nonPE) patients had significantly higher mean all-cause inpatient admissions (3.9 vs 1.4, p < 0.001) per patient per year (PPPY), and MDD-related inpatient admissions (2.3 vs 0.7, p < 0.001) PPPY with more days in hospital PPPY (all-cause: 65.4 vs 17.4 days; MDD-related: 25.9 vs 8.7 days).

CONCLUSIONS

Findings emphasize the need for comprehensive care prioritizing increased vigilance for suicide risk and appropriate follow-up post-discharge among MDD-PE patients.

Comparison of effectiveness and side effects of selegiline transdermal system versus oral monoamine oxidase inhibitors and tricyclic antidepressants for treatment-resistant depression

INTRODUCTION

Several studies suggest that oral monoamine oxidase inhibitors (MAOIs) and tricyclic antidepressants (TCAs) may be more effective than serotonin reuptake inhibitors for treating treatment-resistant depression (TRD). Despite this advantage, they are now rarely prescribed due to concern over serious side effects. In contrast, selegiline transdermal system (STS) may present a safer alternative to oral MAOIs and TCAs; however, no studies have compared STS with other antidepressants.

METHODS

Data from 117 patients who received STS, oral MAOIs, or TCAs for TRD were obtained from a university mood disorder clinic. Two linear regression models were created with severity and number of side effect categories endorsed as the dependent variable. Logistic regression models were created for each side effect category with presence of category as the dependent variable. In all models, antidepressant class was entered as the independent variable, with covariates.

RESULTS

Although STS was less effective than oral MAOIs, it was significantly more effective than TCAs. STS treatment had significantly fewer side effect categories endorsed versus oral MAOIs and TCAs. Patients receiving STS were less likely to report gastrointestinal side effects versus TCAs and to endorse cardiovascular side effects versus oral MAOIs. In contrast, STS patients were more likely to report skin side effects versus oral MAOIs. There were no reported serious adverse events. Amongst the covariates, only the number of prior antidepressant trials predicted more side effect categories endorsed.

CONCLUSIONS

Although oral MAOI therapy has been eschewed by most clinicians, STS may be better tolerated than oral MAOIs and TCAs.

Comparing the Neurocognitive Effects of Right Unilateral Ultra-Brief Pulse Electroconvulsive Therapy and Magnetic Seizure Therapy for the Treatment of Major Depressive Episode

BACKGROUND

Magnetic seizure therapy (MST) is under investigation as a treatment for adults with major depression. Previous research has suggested that MST has antidepressant efficacy comparable to that of electroconvulsive therapy (ECT), but with greater cognitive safety. The objective of the study was to compare the neurocognitive outcomes of patients receiving an acute course of MST with the outcomes of those receiving ECT for the treatment of major depressive episode.

METHODS

This was a between-subjects, double-masked, randomized, multicenter clinical trial. Seventy-three participants with a severe major depressive episode were enrolled and randomly assigned to treatment with MST (n = 35) or ultra-brief pulse right unilateral ECT (n = 38). The main outcome was change in performance from baseline to the end of acute treatment on multiple neurocognitive measures.

RESULTS

Compared with patients who received ECT, patients who received MST had superior cognitive outcomes up to 72 hours posttreatment. Specifically, following MST treatment, there was significant improvement in fine motor dexterity (p = .017) and no significant change in cognitive domains of attention, verbal fluency, executive function, or verbal learning and memory. In contrast, following treatment with ECT, patients demonstrated significantly worse performance on measures of verbal fluency (p < .001), executive function (p = .038), and verbal memory retention (p < .001). Autobiographical memory consistency decreased significantly following treatment with both ECT (p < .001) and MST, although the magnitude of change was greater for ECT.

CONCLUSIONS

The study findings confirm previous work and provide new evidence supporting the enhanced cognitive safety of MST relative to ECT. Future research on MST is warranted to optimize its application to individuals with neuropsychiatric illnesses across the life span.

Cordycepin Extracted from Cordyceps militaris mitigated CUMS-induced depression of rats via targeting GSK3β/β-catenin signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Cordycepin, the main active component of Cordyceps militaris, exhibits various pharmacological activities, including anti-tumor and antioxidant effects. However, its antidepressant effect and the underlying mechanisms remain unclear.

AIM OF REVIEW

This study aimed to explore the antidepressant effect of cordycepin and elucidate the potential molecular mechanisms.

MATERIALS AND METHODS

Chronic unpredictable mild stress (CUMS) rat model was established to assess antidepressant effect of cordycepin. Gas chromatography-mass spectrometry (GC-MS) metabolomics with integrated network pharmacology were used to find differential metabolites in serum, brain, and cerebrospinal fluid of rats and identify potential target by cordycepin. Western blot and Real-time PCR were applied to validate the signaling pathway.

RESULTS

Cordycepin alleviated CUMS-induced depression-like behaviors by weight gain, sucrose preference increment, immobility time reduction, total travelling distance extension and serum corticosterone levels reduction. Metabolomics showed that cordycepin reversed CUMS-induced metabolic disturbances through alanine and TCA cycle metabolism pathways. Network pharmacology identified GSK3β as a potential target. Cordycepin increased protein levels of p-GSK3β, β-catenin and nuclear β-catenin, and enhanced transcription of downstream genes PKM, LDHA, Cyclin D1 and C-myc in brains of CUMS-induced rats.

CONCLUSIONS

This study indicated that cordycepin exerted antidepressant effect by modulating GSK3β/β-catenin pathway, suggesting its potential as a candidate agent for depression.

Is there a risk of esketamine misuse in clinical practice?

In 2019, intranasal esketamine gained approval as a promising therapy for those individuals grappling with treatment-resistant depression. Both clinical trials and real-world studies have underscored its efficacy in alleviating and remitting depressive symptoms, with sustained benefits observed for nearly 4.5 years. As the S-enantiomer of ketamine, esketamine's dosing guidelines and strict medical supervision stem from prior research on ketamine's use in depression and history as a recreational drug. Despite initial concerns, long-term clinical studies have not documented instances of abuse, misuse, addiction or withdrawal, and the same was found in case reports or subsamples of high-risk populations with comorbidities such as substance use disorder or alcohol use disorder. Esketamine has proven to be safe and well tolerated without fostering new-onset substance use in vulnerable groups. Real-world studies reinforced these observations, reporting no adverse events (AEs) related to pharmacological interactions of esketamine with any other substance, and no new-onset drug or alcohol misuse, craving, misuse or diversion of use. Reports of esketamine craving remain rare, with only one case report documented in 2022. Most drug-related AEs reported in pharmacovigilance databases are those identified in the product's technical data sheet and with known reported frequency. More importantly, no register of illicit acquisition of esketamine or its tampering for obtaining ketamine or other altered products was found in our search. Overall, our review confirms esketamine's safety across diverse patient populations, reassuring its responsible use and the scarcity of reports of abuse or misuse since its introduction to the market.

Esketamine Treatment for Depression in Adults: A PRISMA Systematic Review and Meta-Analysis

OBJECTIVE

Intranasal esketamine has been approved as an adjunctive therapy for treatment-resistant major depressive disorder with acute suicidal ideation and behavior. The authors conducted a systematic review and meta-analysis of the available data on its efficacy against depression and suicidality as well as its side effects.

METHODS

MEDLINE was searched with the keyword "esketamine" on March 24, 2024, using the PRISMA method. Data processing and statistical analysis were performed with R, version 4.3.3, and the meta-analysis was performed with the METAFOR package.

RESULTS

Of 1,115 articles initially identified, 87 were included for analysis and discussion. At weeks 2-4, randomized controlled trials were mostly negative or failed; however, the meta-analysis returned a weak but significant positive effect for depression (effect size range, 0.15-0.23 at weeks 2-4), similar to augmentation strategies with atypical antipsychotics for treatment-resistant depression. The effect size concerning suicidality was not significant at any time point. The sensitivity analysis produced the same results.

CONCLUSIONS

The study findings suggest that esketamine's efficacy as an add-on to antidepressants is modest in treatment-resistant depression (similar to augmentation strategies with atypical antipsychotics) and is absent against suicidality itself. These findings need to be considered in light of esketamine's abuse potential and the fact that long-term effects are still not fully known. Some alarming signs concerning deaths and emerging suicidality during the testing phase are discussed, along with other regulatory issues.

A Retrospective Analysis of the Impact of Electroconvulsive Therapy on Anxiety Symptoms in Patients With Treatment-Resistant Depression

BACKGROUND

Electroconvulsive therapy (ECT) is an effective treatment for treatment-resistant depression (TRD). There are limited data on the improvement of anxiety symptoms in patients receiving ECT for TRD.

OBJECTIVE

The aim of the study was to examine the extent to which anxiety symptom severity improves, relative to improvements in depressive symptoms, in TRD patients receiving an acute course of ECT.

METHODS

A retrospective chart review of 117 TRD patients who received an acute ECT course in a naturalistic outpatient setting was conducted. Symptomatic response was measured using the Beck Depression Inventory II and Generalized Anxiety Disorder 7 Scale. Two generalized estimating equation models assessed the degree of change in anxious symptoms relative to the change in depressive symptoms.

RESULTS

Both depression (-0.09, P < 0.001) and anxiety (-0.08, P < 0.001) improved after ECT treatment, with a greater standardized decrease for symptoms of depression. Higher levels of anxiety over the treatment (-0.42, P < 0.001) were associated with smaller antidepressant improvements.

CONCLUSIONS

ECT may improve symptoms of anxiety in patients with TRD. Anxiety symptoms show a favorable trajectory of improvement, though to a lesser extent, relative to changes in symptoms of depression. Higher symptoms of anxiety throughout the treatment course may be a negative predictor of antidepressant response in ECT.

Insights for the Next Generation of Ketamine for the Treatment of Depressive Disorder

Treatment-resistant depression responds quickly to ketamine. As an N-methyl-d-aspartate receptor (NMDAR) antagonist, ketamine may affect prefrontal cortex (PFC) neurons. Recent investigations reveal that the (R)-enantiomer is the most effective and least abuseable antidepressant. The Food and Drug Administration approves only the (S)-enantiomer for medical usage. (2R,6R)-Hydroxynorketamine (HNK) inhibits mGlu2, linked to a Gi, in presynaptic glutamatergic neurons, increasing brain-derived neurotrophic factor (BDNF) release, which autocrinely activates Tropomyosin receptor kinase B (TrkB) and promotes synaptogenesis. Ketamine, originally an anesthetic, has garnered attention for its many pharmacological effects, including its potential as a rapid-acting antidepressant and recreational use. In this Perspective, we explore the synthesis, pharmacology, metabolism, and effects of ketamine and its metabolites in animal and human studies to explain the difference in the biological activity between the enantiomers.

Application of functional near-infrared spectroscopy and machine learning to predict treatment response after six months in major depressive disorder

Depression treatment responses vary widely among individuals. Identifying objective biomarkers with predictive accuracy for therapeutic outcomes can enhance treatment efficiency and avoid ineffective therapies. This study investigates whether functional near-infrared spectroscopy (fNIRS) and clinical assessment information can predict treatment response in major depressive disorder (MDD) through machine-learning techniques. Seventy patients with MDD were included in this 6-month longitudinal study, with the primary treatment outcome measured by changes in the Hamilton Depression Rating Scale (HAM-D) scores. fNIRS and clinical information were strictly evaluated using nested cross-validation to predict responders and non-responders based on machine-learning models, including support vector machine, random forest, XGBoost, discriminant analysis, Naïve Bayes, and transformers. The task change of total haemoglobin (HbT), defined as the difference between pre-task and post-task average HbT concentrations, in the dorsolateral prefrontal cortex (dlPFC) is significantly correlated with treatment response (p < 0.005). Leveraging a Naïve Bayes model, inner cross-validation performance (bAcc = 70% [SD = 4], AUC = 0.77 [SD = 0.04]) and outer cross-validation results (bAcc = 73% [SD = 3], AUC = 0.77 [SD = 0.02]) were yielded for predicting response using solely fNIRS data. The bimodal model combining fNIRS and clinical data showed inferior performance in outer cross-validation (bAcc = 68%, AUC = 0.70) compared to the fNIRS-only model. Collectively, fNIRS holds potential as a scalable neuroimaging modality for predicting treatment response in MDD.

Neurobiological Mechanisms Underlying Psychological Dysfunction After Brain Injuries

Despite the presentation of similar psychological symptoms, psychological dysfunction secondary to brain injury exhibits markedly lower treatment efficacy compared to injury-independent psychological dysfunction. This gap remains evident, despite extensive research efforts. This review integrates clinical and preclinical evidence to provide a comprehensive overview of the neurobiological mechanisms underlying neuropsychological disorders, focusing on the role of key brain regions in emotional regulation across various forms of brain injuries. It examines therapeutic interventions and mechanistic targets, with the primary goal of identifying pathways for targeted treatments. The review highlights promising therapeutic avenues for addressing injury-associated psychological dysfunction, emphasizing Nrf2, neuropeptides, and nonpharmacological therapies as multi-mechanistic interventions capable of modulating upstream mediators to address the complex interplay of factors underlying psychological dysfunction in brain injury. Additionally, it identifies sexually dimorphic factors as potential areas for further exploration and advocates for detailed investigations into sex-specific patterns to uncover additional contributors to these disorders. Furthermore, it underscores significant gaps, particularly the inadequate consideration of interactions among causal factors, environmental influences, and individual susceptibilities. By addressing these gaps, this review provides new insights and calls for a paradigm shift toward a more context-specific and integrative approach to developing targeted therapies for psychological dysfunction following brain injuries.

Therapeutic Approaches to Tackle the Challenge of Depression That Is Resistant to Treatment-A Narrative Review

Background and Aims

The lack of therapeutic response characterizes treatment-resistant depression despite undergoing at least two adequate monotherapy trials with medications from distinct pharmacologic classes. The inability to attain remission in patients diagnosed with major depressive disorder (MDD) is a significant issue of concern within public health. Therefore, the management of treatment-resistant depression (TRD) poses significant obstacles for both patients and healthcare professionals. Our goal was to investigate the published literature concerning different options for treatment for TRD, including those that do not involve the use of medications.

Methods

We thoroughly searched the literature in the Google Scholar, PubMed, and ScienceDirect databases to find publications relevant to our narrative review and extracted data from appropriate data. For this review, literary works written solely in English were chosen.

Results

Ongoing research is being conducted to explore the treatment options for TRD, including pharmacological and nonpharmacological interventions. Pharmacological interventions include a wide range of therapeutic approaches, including but not limited to investigating innovative medications and strategies such as augmentation, switching, and combination therapies involving established and emerging drugs. Nonpharmacological interventions, including brain stimulation such as theta burst stimulation, deep brain stimulation, electroconvulsive therapy, repetitive transcranial magnetic stimulation, intermittent transcranial magnetic stimulation, and magnetic seizure therapy, as well as psychotherapeutic approaches, are being explored for the management of TRD in both present and future contexts.

Conclusion

Researchers are dedicating significant resources to the aforementioned therapeutic interventions to advance the development of novel and efficacious treatment options for TRD and enhance our comprehension of the underlying disease. This review focused on looking at recent research concerning therapeutic interventions for TRD.

Recognition and management of treatment-resistant depression

ABSTRACT

Major depressive disorder (MDD) is a common psychiatric condition that causes considerable morbidity and disability. MDD is characterized by recurrent depressive episodes that can result in loss of productivity, job insecurity, social isolation, and suicidality. Primary care providers frequently provide the initial management of MDD; however, some patients do not respond to first- or second-line treatments, a condition called treatment-resistant depression (TRD). Understanding how to accurately diagnose and manage TRD is important for clinicians.

Neuroprotective Efficacy and Complementary Treatment with Medicinal Herbs: A Comprehensive Review of Recent Therapeutic Approaches in Epilepsy Management

Central Nervous System (CNS) disorders affect millions of people worldwide, with a significant proportion experiencing drug-resistant forms where conventional medications fail to provide adequate seizure control. This abstract delves into recent advancements and innovative therapies aimed at addressing the complex challenge of CNS-related drug-resistant epilepsy (DRE) management. The idea of precision medicine has opened up new avenues for epilepsy treatment. Herbs such as curcumin, ginkgo biloba, panax ginseng, bacopa monnieri, ashwagandha, and rhodiola rosea influence the BDNF pathway through various mechanisms. These include the activation of CREB, inhibition of NF-κB, modulation of neurotransmitters, reduction of oxidative stress, and anti- inflammatory effects. By promoting BDNF expression and activity, these herbs support neuroplasticity, cognitive function, and overall neuronal health. Novel antiepileptic drugs (AEDs) with distinct mechanisms of action demonstrate efficacy in refractory cases where traditional medications falter. Additionally, repurposing existing drugs for antiepileptic purposes presents a cost-effective strategy to broaden therapeutic choices. Cannabidiol (CBD), derived from cannabis herbs, has garnered attention for its anticonvulsant properties, offering a potential adjunctive therapy for refractory seizures. In conclusion, recent advances and innovative therapies represent a multifaceted approach to managing drug-resistant epilepsy. Leveraging precision medicine, neurostimulation technologies, novel pharmaceuticals, and complementary therapies, clinicians can optimize treatment outcomes and improve the life expectancy of patients living with refractory seizures. Genetic testing and biomarker identification now allow for personalized therapeutic approaches tailored to individual patient profiles. Utilizing next-generation sequencing techniques, researchers have elucidated genetic mutations.

Long-term characterisation of the relationship between change in depression severity and change in inflammatory markers following inflammation-stratified treatment with vortioxetine augmented with celecoxib or placebo

BACKGROUND

Major depressive disorder (MDD) is a highly prevalent condition with a substantial incidence of relapse or treatment resistance. A subset of patients show evidence of low-grade inflammation, with these patients having a higher likelihood of more severe or difficult to treat courses of illness. Anti-inflammatory treatment of MDD has been investigated with mixed results, and no known studies have included assessments beyond cessation of the anti-inflammatory agent, meaning it remains unknown if any benefit from treatment persists. The objective of the present study was to investigate treatment outcomes up to 29 weeks post-cessation of celecoxib or placebo augmentation of an antidepressant, and how concentrations of selected inflammatory markers change over the same period.

METHODS

The PREDDICT parallel-group, randomised, double-blind, placebo-controlled trial (University of Adelaide, Australia) ran from December 2017 to April 2020. Participants with MDD were stratified into normal range or elevated inflammation strata according to screening concentrations of high sensitivity C-reactive protein (hsCRP). Participants were randomised to treatment with vortioxetine and celecoxib or vortioxetine and placebo for six weeks, and vortioxetine alone for an additional 29 weeks (35 total weeks). Following a previous publication of results from the six-week RCT phase, exploratory analyses were performed on Montgomery-Åsberg Depression Rating Scale (MADRS) scores, response and remission outcomes, and selected peripheral inflammatory markers across the entire study duration up to week 35.

RESULTS

Participants retained at each observation were baseline N=119, week 2 N=115, week 4 N=103, week 6 N=104, week 8 N=98, week 22 N=81, and week 35 N=60. Those in the elevated hsCRP celecoxib-augmented group had a statistically significantly greater reduction in MADRS score from baseline to week 35 compared to all other groups, demonstrating the greatest clinical improvement long-term, despite no group or strata differences at preceding time points. Response and remission outcomes did not differ by treatment group or hsCRP strata at any time point. Changes in hsCRP between baseline and week 35 and Tumour Necrosis Factor-α (TNF-α) concentrations between baseline and week 6 and baseline and week 35 were statistically significantly associated with MADRS scores observed at week 6 and week 35 respectively, with reducing TNF-α concentrations associated with reducing MADRS scores and vice versa in each case. A post-hoc stratification of the participant cohort by baseline TNF-α concentrations led to significant prediction by the derived strata on clinical response at weeks 6, 8 and 35, with participants with elevated baseline TNF-α less likely to achieve clinical response.

INTERPRETATION

The present analysis suggests for the first time a possible longer-term clinical benefit of celecoxib augmentation of vortioxetine in inflammation-associated MDD treatment. However, further research is needed to confirm the finding and to ascertain the reason for such a delayed effect. Furthermore, the trial suggests that TNF-α may have a stronger relationship with anti-inflammatory MDD treatment outcomes than hsCRP, and should be investigated further for potential predictive utility.

CLINICAL TRIALS REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12617000527369p. Registered on 11 April 2017, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12617000527369p.

Magnetic seizure therapy for unipolar and bipolar depression: An up to date systematic review

BACKGROUND

Magnetic seizure therapy (MST) has emerged as a promising alternative to electroconvulsive therapy (ECT) for treatment-resistant depression. Previous systematic reviews and meta analysis already showed its primary results, however, there are no recent reviews updating these findings.

OBJECTIVES

This systematic review aimed to make an updated systematic review of MST on unipolar and bipolar depression.

METHODS

We conducted a search considering databases (PubMed/MEDLINE, EMBASE, Web of Science, Scopus). Studies were included if they investigated MST in human subjects for unipolar or bipolar depression, and not restricting to year or language.

RESULTS

Data resulted in 15 studies, corresponding to 300 participants that received MST. Most studies were pilot, open-label or secondary analyses (n = 12). Participants that received MST had a response and remission rates ranging from 26.9% to 72.2% and 11.1% to 61.1%, respectively. The most common stimulation regions were vertex and prefrontal cortex, with frequencies between 25-100 Hz and duration of 6-24 sessions (2-3 times a week). Few side effects were reported.

CONCLUSIONS

MST shows to be effective and well-tolerated treatment for depression. Larger, double-blinded RCTs with standardised mood, cognitive, and side effect assessments are needed to confirm these findings.

Understanding immune system dysfunction and its context in mood disorders: psychoneuroimmunoendocrinology and clinical interventions

Mood disorders include a set of psychiatric manifestations of increasing prevalence in our society, being mainly represented by major depressive disorder (MDD) and bipolar disorder (BD). The etiopathogenesis of mood disorders is extremely complex, with a wide spectrum of biological, psychological, and sociocultural factors being responsible for their appearance and development. In this sense, immune system dysfunction represents a key mechanism in the onset and pathophysiology of mood disorders, worsening mainly the central nervous system (neuroinflammation) and the periphery of the body (systemic inflammation). However, these alterations cannot be understood separately, but as part of a complex picture in which different factors and systems interact with each other. Psychoneuroimmunoendocrinology (PNIE) is the area responsible for studying the relationship between these elements and the impact of mind-body integration, placing the immune system as part of a whole. Thus, the dysfunction of the immune system is capable of influencing and activating different mechanisms that promote disruption of the psyche, damage to the nervous system, alterations to the endocrine and metabolic systems, and disruption of the microbiota and intestinal ecosystem, as well as of other organs and, in turn, all these mechanisms are responsible for inducing and enhancing the immune dysfunction. Similarly, the clinical approach to these patients is usually multidisciplinary, and the therapeutic arsenal includes different pharmacological (for example, antidepressants, antipsychotics, and lithium) and non-pharmacological (i.e., psychotherapy, lifestyle, and electroconvulsive therapy) treatments. These interventions also modulate the immune system and other elements of the PNIE in these patients, which may be interesting to understand the therapeutic success or failure of these approaches. In this sense, this review aims to delve into the relationship between immune dysfunction and mood disorders and their integration in the complex context of PNIE. Likewise, an attempt will be made to explore the effects on the immune system of different strategies available in the clinical approach to these patients, in order to identify the mechanisms described and their possible uses as biomarkers.

MicroRNA Expression Profile Is Altered by Short-Term and Chronic Lithium Treatment in a Rat Model of Depression

Depression is a common disease that affects 3.8% of the global population. Despite various antidepressant treatments, one-third of patients do not respond to antidepressants, therefore augmentation with mood stabilizers such as lithium may be required in this group. One of the suggested pathomechanisms of depression is the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and recent reports showed that microRNAs (miRNA) can impact its activity by epigenetic regulation. We aimed to explore the miRNA expression profile in the depression model and its changes upon short-term and chronic lithium treatment in the rat brain (pituitary, hypothalamus, and hippocampus). We used a chronic mild stress rat model of depression and short- and long-term lithium treatment. The behavior was assessed by an open-field test. The miRNA expression profile in the pituitary was estimated by sequencing and validated in the hypothalamus and hippocampus with qPCR. We found several miRNAs in the pituitary that were significantly altered between CMS-exposed and control rats as well as after short- and long-term lithium treatment. MicroRNAs chosen for validation in the hypothalamus and hippocampus (rno-miR-146a-5p, rno-miR-127-3p) showed no significant changes in expression. We performed in silico analysis and estimated potential pathways involved in lithium action for miRNAs differentially expressed in the pituitary at different time points. Specific microRNA subsets showed altered expression in the pituitary in depression model upon short- and long-term lithium treatment. We identified that biological pathways of target genes for these altered miRNAs differ, with the Foxo pathway potentially involved in disease development.

The effects of chronic desipramine treatment on neurotrophin-3 in the brain of mice with selective depletion of CREB and CREM in noradrenergic neurons

The disturbances in neurotrophic support are thought to be one of the main causes of depression, which depend not only on the neurotrophins themselves but also on the molecules regulating their synthesis and effector functions. One such molecule is cAMP responsive element binding protein (CREB), which role in depression and antidepressant drugs mechanism of action has been extensively studied. However, CREB's effects vary depending on brain structure, necessitating specific transgenic models for studying its function. Moreover, deletion of CREB enhances cAMP response element modulator (CREM) expression, suspected to compensate for CREB in its absence. Previously, mice lacking CREB in noradrenergic neurons and CREM (Creb1DbhCreCrem-/-) showed to be insensitive to acute desipramine, whereas mice lacking only CREB (Creb1DbhCre) showed similar effects as wild type animals (w/t). As neurotrophic changes require chronic antidepressant treatment, in current study mice (w/t, Creb1DbhCre and Creb1DbhCreCrem-/-; both males and females) were given desipramine for 21 days, to assess the effects of the drug on CREB, neurotrophins and their receptors in the hippocampus and prefrontal cortex. Interestingly, desipramine had no effect on CREB in neither of studied groups. However, both male and female mice lacking CREB and CREM displayed alterations in neurotrophin-3 (NTF3) expression or protein levels, modulated by desipramine. These findings suggest NTF3 is connected with inhibited response to acute and probably chronic desipramine administration in Creb1DbhCreCrem-/- mice, although in w/t chronic desipramine had no effect on NTF3. Nevertheless, our findings give insight into the role of non-BDNF neurotrophins in the mechanism of antidepressant drugs.

Molecular signature underlying (R)-ketamine rapid antidepressant response on anhedonic-like behavior induced by sustained exposure to stress

Anhedonia induced by sustained stress exposure is a hallmark symptom of major depressive disorder (MDD) and in rodents, it can be accessed through the sucrose preference test (SPT). (R)-ketamine is a fast-acting antidepressant with less detrimental side effects and abuse liability compared to racemic ketamine. The present study combined high-throughput proteomics and network analysis to identify molecular mechanisms involved in chronic variable stress (CVS)-induced anhedonia and promising targets underlying (R)-ketamine rapid antidepressant response. Male Wistar rats were subjected to CVS for five weeks. Based on the SPT, animals were clustered into resilient or anhedonic-like (ANH) groups. ANH rats received a single dose of saline or (R)-ketamine (20 mg/kg, i.p.), which was proceeded by treatment response evaluation. After prefrontal cortex collection, proteomic analysis was performed to uncover the differentially expressed proteins (DEPs) related to both anhedonic-like behavior and pharmacological response. The behavioral assessment showed that the ANH animals had a significant decrease in SPT, and that (R)-ketamine responders showed a reversal of anhedonic-like behavior. On a molecular level, anhedonia-like behavior was associated with the downregulation of Neuronal Pentraxin Receptor (Nptxr) and Galectin-1 (Gal-1). These data reinforce a disruption in the inflammatory response, neurotransmitter receptor activity, and glutamatergic synapses in chronic stress-induced anhedonia. (R)-ketamine response-associated DEPs included novel potential targets involved in the modulation of oxidative stress, energetic metabolism, synaptogenesis, dendritic arborization, neuroinflammation, gene expression, and telomere length, converging to biological themes extensively documented in MDD physiopathology. Our data provide valuable insights into the molecular mechanisms underlying the response to (R)-ketamine and highlight these pathways as potential therapeutic targets for anhedonia. By addressing proteins involved in oxidative stress, energy metabolism, synaptogenesis, dendritic arborization, neuroinflammation, gene expression, and telomere length, we can target multiple key factors involved in the pathophysiology of MDD. Modulating these proteins could open avenues for novel therapeutic strategies and deepen our understanding of anhedonia, offering hope for improved outcomes in individuals facing this challenging condition. However, additional studies will be essential to validate these findings and further explore their therapeutic implications.

Vagus nerve stimulation (VNS): recent advances and future directions

PURPOSE

Vagus nerve stimulation (VNS) is emerging as a unique and potent intervention, particularly within neurology and psychiatry. The clinical value of VNS continues to grow, while the development of noninvasive options promises to change a landscape that is already quickly evolving. In this review, we highlight recent progress in the field and offer readers a glimpse of the future for this bright and promising modality.

METHODS

We compiled a narrative review of VNS literature using PubMed and organized the discussion by disease states with approved indications (epilepsy, depression, obesity, post-stroke motor rehabilitation, headache), followed by a section highlighting novel, exploratory areas of VNS research. In each section, we summarized the current role, recent advancements, and future directions of VNS in the treatment of each disease.

RESULTS

The field continues to gain appreciation for the clinical potential of this modality. VNS was initially developed for treatment-resistant epilepsy, with the first depression studies following shortly thereafter. Overall, VNS has gained approval or clearance in the treatment of medication-refractory epilepsy, treatment-resistant depression, obesity, migraine/cluster headache, and post-stroke motor rehabilitation.

CONCLUSION

Noninvasive VNS represents an opportunity to bridge the translational gap between preclinical and clinical paradigms and may offer the same therapeutic potential as invasive VNS. Further investigation into how VNS parameters modulate behavior and biology, as well as how to translate noninvasive options into the clinical arena, are crucial next steps for researchers and clinicians studying VNS.

Intranasal esketamine for patients with major depressive disorder: A systematic review and meta-analysis

A large number of people worldwide grapple with Major Depressive Disorder (MDD), and a significant portion of them confront resistance to conventional antidepressant treatments. Esketamine, an innovative intervention, has garnered attention due to its rapid-acting antidepressant effects. This meta-analysis aimed to evaluate the efficacy and safety of esketamine in individuals with MDD and Treatment-Resistant Depression (TRD). We performed an extensive search of electronic databases, including PubMed, EMBASE, and Cochrane Library, covering the period from inception to January 15, 2024, to identify clinical trials investigating the efficacy, safety, and tolerability of esketamine in individuals with MDD and TRD. Meta-analyses were conducted using a random-effect model, with the risk ratio (RR) chosen as the effect size. After screening, nine studies met inclusion criteria comprising 1752 patients. Esketamine dosages varied from 28 to 84 mg, administered intranasally in conjunction with an oral antidepressant. Intranasal esketamine exhibited significantly higher remission rates compared to the placebo (RR = 1.371, 95% CI: 1.194 to 1.574, p < 0.0001). Subgroup analysis revealed that the 84 mg and flexible doses were particularly effective. Moreover, intranasal esketamine demonstrated higher response rates compared to the placebo (RR = 1.274, 95% CI: 1.108 to 1.465, p-value = 0.001). Although adverse events were common in the esketamine group, they were generally tolerable. Intranasal esketamine demonstrated effectiveness in reducing scores among patients with MDD and TRD. The drug exhibited both safety and tolerability. However, further research is warranted to investigate its long-term effects and efficacy in specific patient subgroups.

Comorbid anxiety, loneliness, and chronic pain as predictors of intervention outcomes for subclinical depressive symptoms in older adults: evidence from a large community-based study in Hong Kong

BACKGROUND

Depression is among the leading causes of the global burden of disease and is associated with substantial morbidity in old age. The importance of providing timely intervention, particularly those with subclinical symptoms, has thus increasingly been emphasised. Despite their overall effectiveness, a small but notable subgroup tends to be less responsive to interventions. Identifying predictors of non-remission and non-response is critical to inform future strategies for optimising intervention outcomes.

METHODS

A total of 4153 older adults aged 60 years and above with subclinical depressive symptoms (Patient Health Questionnaire-9 [PHQ-9] = 5-19) were recruited from JC JoyAge, a large-scale collaborative stepped-care intervention service across Hong Kong. A wide range of clinical and modifiable risk and protective factors at baseline were assessed, including depressive symptoms, anxiety symptoms, loneliness, suicidal ideation, cognitive capacity, multimorbidity, chronic pain, need for informal care due to mental health reasons, history of abuse, and sociodemographic characteristics. Separate multivariable logistic regression models were applied to identify predictors of non-remission (PHQ-9 ≥ 5) and non-response (< 50% reduction in PHQ-9) following intervention.

RESULTS

The rates of non-remission and non-response were 18.9% (n = 784) and 23.0% (n = 956), respectively. Comorbid anxiety symptoms (adjusted odds ratio [aOR] = 2.08, CI = 1.72-2.51; 1.28, 1.05-1.57), loneliness (2.00, 1.66-2.42; 1.67, 1.38-2.01), need for informal care (1.86, 1.49-2.33; 1.48, 1.18-1.85), lower cognitive capacity (0.95, 0.93-0.97; 0.94, 0.92-0.96), and absence of chronic pain (0.59, 0.48-0.72; 0.76, 0.64-0.91) predicted both non-remission and non-response. Meanwhile, moderate-to-severe depressive symptoms predicted higher odds of non-remission (1.41, 1.18-1.69) and lower odds of non-response (0.28, 0.23-0.34), respectively. Subgroup analyses conducted separately in older adults with mild and moderate-to-severe depressive symptoms at baseline revealed that comorbid anxiety, loneliness, need for informal care, and absence of chronic pain were consistent predictors of non-remission. Those with non-remission and non-response showed more depression-related functional impairments and poorer health-related quality of life post-intervention.

CONCLUSIONS

Older adults with subclinical depressive symptoms showing comorbid anxiety, higher loneliness, need for informal care, and chronic pain may be offered more targeted interventions in future services. A personalised risk-stratification approach may be helpful.

TRIAL REGISTRATION

ClinicalTrials.gov identifiers: NCT03593889 (registered 29 May 2018), NCT04863300 (registered 23 April 2021).

Faecalibacterium prausnitzii, FOS and GOS loaded synbiotic reverses treatment-resistant depression in rats: Restoration of gut-brain crosstalk

Alterations in commensal gut microbiota, such as butyrate-producing bacteria and its metabolites, have been linked to stress-related brain disorders, including depression. Herein, we investigated the effect of Faecalibacterium prausnitzii (ATCC-27766) administered along with fructooligosaccharides (FOS) and galactooligosaccharides (GOS) in a rat model of treatment-resistant depression (TRD). The behavioral changes related to anxiety-, anhedonia- and despair-like phenotypes were recorded employing elevated plus maze, sucrose-preference test, and forced-swim test, respectively. Rats exposed to unpredictable chronic mild-stress (UCMS) and adrenocorticotropic hormone (ACTH) injections exhibited a TRD-like phenotype. Six-week administration of F. prausnitzii and FOS + GOS ameliorated TRD-like conditions in rats. This synbiotic treatment also restored the decreased levels of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate in the fecal samples of TRD rats. Synbiotic-recipient TRD rats displayed an increased abundance of Lactobacillus helveticus, Lactobacillus hamsteri, and Ruminococcus flavefaciens. Moreover, more mucus-producing goblet cells were seen in the colon of synbiotic-treated rats, suggesting improved gut health. The synbiotic treatment effectively modulated neuroinflammation by reducing proinflammatory cytokines (IFN-γ, TNF-α, CRP, and IL-6). It normalized the altered levels of key neurotransmitters such as serotonin, gamma-aminobutyric acid, noradrenaline, and dopamine in the hippocampus and/or frontal cortex. The enhanced expression of brain-derived neurotrophic factor, tryptophan hydroxylase 1, and serotonin transporter-3 (SERT-3), and reduced levels of indoleamine 2,3-dioxygenase 1 (IDO-1) and kynurenine metabolite were observed in the synbiotic-treated group. We suggest that F. prausnitzii and FOS + GOS-loaded synbiotic may reverse the TRD-like symptoms in rats by positively impacting gut health, neuroinflammation, neurotransmitters, and gut microbial composition.

Brain-based correlates of depression and traumatic brain injury: a systematic review of structural and functional magnetic resonance imaging studies

Introduction

Depression is prevalent after traumatic brain injury (TBI). However, there is a lack of understanding of the brain-based correlates of depression post-TBI. This systematic review aimed to synthesize findings of structural and functional magnetic resonance imaging (MRI) studies to identify consistently reported neural correlates of depression post-TBI.

Methods

A search for relevant published studies was conducted through OVID (MEDLINE, APA PsycINFO, and Embase), with an end date of August 3rd, 2023. Fourteen published studies were included in this review.

Results

TBI patients with depression exhibited distinct changes in diffusion- based white matter fractional anisotropy, with the direction of change depending on the acuteness or chronicity of TBI. Decreased functional connectivity (FC) of the salience and default mode networks was prominent alongside the decreased volume of gray matter within the insular, dorsomedial prefrontal, and ventromedial prefrontal cortices. Seven studies reported the correlation between observed neuroimaging and depression outcomes. Of these studies, 42% indicated that FC of the bilateral medial temporal lobe subregions was correlated with depression outcomes in TBI.

Discussion

This systematic review summarizes existing neuroimaging evidence and reports brain regions that can be leveraged as potential treatment targets in future studies examining depression post-TBI.

A Phase 1 Assessment of the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of (2R,6R)-Hydroxynorketamine in Healthy Volunteers

(R,S)-Ketamine (ketamine) is a dissociative anesthetic that also possesses analgesic and antidepressant activity. Undesirable dissociative side effects and misuse potential limit expanded use of ketamine in several mental health disorders despite promising clinical activity and intensifying medical need. (2R,6R)-Hydroxynorketamine (RR-HNK) is a metabolite of ketamine that lacks anesthetic and dissociative activity but maintains antidepressant and analgesic activity in multiple preclinical models. To enable future assessments in selected human indications, we report the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of RR-HNK in a Phase 1 study in healthy volunteers (NCT04711005). A six-level single-ascending dose (SAD) (0.1-4 mg/kg) and a two-level multiple ascending dose (MAD) (1 and 2 mg/kg) study was performed using a 40-minute IV administration emulating the common practice for ketamine administration for depression. Safety assessments showed RR-HNK possessed a minimal adverse event profile and no serious adverse events at all doses examined. Evaluations of dissociation and sedation demonstrated that RR-HNK did not possess anesthetic or dissociative characteristics in the doses examined. RR-HNK PK parameters were measured in both the SAD and MAD studies and exhibited dose-proportional increases in exposure. Quantitative electroencephalography (EEG) measurements collected as a PD parameter based on preclinical findings and ketamine's established effect on gamma-power oscillations demonstrated increases of gamma power in some participants at the lower/mid-range doses examined. Cerebrospinal fluid examination confirmed RR-HNK exposure within the central nervous system (CNS). Collectively, these data demonstrate RR-HNK is well tolerated with an acceptable PK profile and promising PD outcomes to support the progression into Phase 2.

Engineering and Technological Advancements in Repetitive Transcranial Magnetic Stimulation (rTMS): A Five-Year Review

In the past five years, repetitive transcranial magnetic stimulation (rTMS) has evolved significantly, driven by advancements in device design, treatment protocols, software integration, and brain-computer interfaces (BCIs). This review evaluates how these innovations enhance the safety, efficacy, and accessibility of rTMS while identifying key challenges such as protocol standardization and ethical considerations. A structured review of peer-reviewed studies from 2019 to 2024 focused on technological and clinical advancements in rTMS, including AI-driven personalized treatments, portable devices, and integrated BCIs. AI algorithms have optimized patient-specific protocols, while portable devices have expanded access. Enhanced coil designs and BCI integration offer more precise and adaptive neuromodulation. However, challenges remain in standardizing protocols, addressing device complexity, and ensuring equitable access. While recent innovations improve rTMS's clinical utility, gaps in long-term efficacy and ethical concerns persist. Future research must prioritize standardization, accessibility, and robust ethical frameworks to ensure rTMS's sustainable impact.

Challenges and Opportunities in Managing Geriatric Depression: The Role of Personalized Medicine and Age-Appropriate Therapeutic Approaches

The global aging population has experienced rapid growth in recent decades, leading to an increased prevalence of psychiatric disorders, particularly depression, among older adults. Depression in the geriatric population is often compounded by chronic physical conditions and various psychosocial factors, significantly impacting their quality of life. The main question raised in this review is as follows: how can personalized medicine and age-appropriate therapeutic approaches improve the management of geriatric depression? This paper explores the epidemiology of geriatric depression, highlighting the influence of gender, race, and socioeconomic status on its prevalence. The classification and diagnosis of geriatric depressive disorders, based on ICD-11 and DSM-5 criteria, reveal the complexity of managing these conditions in older adults. Personalized medicine (PM) emerges as a promising approach, focusing on tailoring treatments to the individual's genetic, clinical, and environmental characteristics. However, the application of PM in this demographic faces challenges, particularly in the context of pharmaceutical forms. The need for age-appropriate drug delivery systems is critical, given the prevalence of polypharmacy and issues such as dysphagia among the older patients. This study emphasizes the importance of developing patient-centric formulations to enhance the effectiveness of personalized therapy in geriatric patients.

Early differences in lassitude predicts outcomes in Stanford Neuromodulation Therapy for difficult to treat depression

Stanford Neuromodulation Therapy (SNT), has recently shown rapid efficacy in difficult to treat (DTT) depression. We conducted an exploratory analysis of individual symptom improvements during treatment, correlated with fMRI, to investigate this rapid improvement in 23 DTT participants from an SNT RCT (12 active, 11 sham). Montgomery-Åsberg Depression Rating Scale item 7 (Lassitude) was the earliest to show improvements between active and sham, as early as treatment day 2. Lassitude score at treatment day 3 was predictive of response at 4 weeks post-treatment and response immediately after treatment. Participants with lower lassitude scores at treatment day 3 had different patterns of sgACC functional connectivity compared to participants with higher scores in both baseline and post-treatment minus baseline analyses. Further work will aim to first replicate these preliminary findings, and then to extend these findings and examine how SNT may affect lassitude and behavioral activation early in treatment.

Explainable Multi-Layer Dynamic Ensemble Framework Optimized for Depression Detection and Severity Assessment

BACKGROUND

Depression is a pervasive mental health condition, particularly affecting older adults, where early detection and intervention are essential to mitigate its impact. This study presents an explainable multi-layer dynamic ensemble framework designed to detect depression and assess its severity, aiming to improve diagnostic precision and provide insights into contributing health factors.

METHODS

Using data from the National Social Life, Health, and Aging Project (NSHAP), this framework combines classical machine learning models, static ensemble methods, and dynamic ensemble selection (DES) approaches across two stages: detection and severity prediction. The depression detection stage classifies individuals as normal or depressed, while the severity prediction stage further classifies depressed cases as mild or moderate-severe. Finally, a confirmation depression scale prediction model estimates depression severity scores to support the two stages. Explainable AI (XAI) techniques are applied to improve model interpretability, making the framework more suitable for clinical applications.

RESULTS

The framework's FIRE-KNOP DES algorithm demonstrated high efficacy, achieving 88.33% accuracy in depression detection and 83.68% in severity prediction. XAI analysis identified mental and non-mental health indicators as significant factors in the framework's performance, emphasizing the value of these features for accurate depression assessment.

CONCLUSIONS

This study emphasizes the potential of dynamic ensemble learning in mental health assessments, particularly in detecting and evaluating depression severity. The findings provide a strong foundation for future use of dynamic ensemble frameworks in mental health assessments, demonstrating their potential for practical clinical applications.

Critical appraisal of evidence supporting prescription of psychedelics from clinic websites in Ontario, Canada

Psychedelics, including ketamine, 3,4-Methyl enedioxy methamphetamine (MDMA), and psilocybin, have gained attention for their potential therapeutic role in mental health treatment. While recreational use is prohibited in Canada, medicinal exemptions can be granted. There are several psychedelic clinics in Ontario, Canada, promoting the use of psychedelics for a variety of medical indications. Our objective was to identify the indications for which psychedelics are being prescribed in Ontario clinics and assess the quality of evidence used to support these claims. Internet searches were conducted using Google and Bing to identify psychedelic clinics in Ontario. Inclusion criteria was as follow: clinics were physically located in Ontario, had a functioning website link, and demonstrated involvement of a licensed physician or nurse practitioner. Identified clinics were evaluated for their claims of effectiveness, the quality of evidence used to support these claims, and statements on psychedelic-related harms. The cited studies were appraised for quality using Oxford Centre for Evidence-Based Medicine Levels of Evidence, "level 5" being the lowest quality and "level 1" being the highest quality. Out of 200 search results, 10 psychedelic clinic websites met our inclusion criteria. These clinics advertised psychedelics for 47 medical conditions, most commonly for depression. Only 2 out of 10 clinics described potential risks associated with psychedelic use. There were 29 studies cited by these websites, majority coming from "level 4" evidence consisting of case-series and case-control studies. Overall, the cited evidence quality was low to moderate. Psychedelic clinics in Ontario promote a wide range of medical indications for psychedelics using primarily low to moderate "level 4" evidence. There is limited information shared on the potential adverse effects of psychedelics. Our study emphasizes the importance of using transparent and high-quality evidence by clinics and clinicians to ensure safe and effective use of psychedelics in mental health treatments.

Comorbidity, Treatment, and Service Utilization Patterns in Difficult-to-Treat Depression Patients: A Retrospective Study in a Portuguese Community Mental Health Team

Background and Objectives: Observational studies with data from real-world clinical practice with patients with difficult-to-treat depression (DTD) are rare. This study aims to collect observational data from the real-world clinical practice of a Portuguese community mental health team (CMHT) on the prevalence of DTD and to explore differences between DTD and non-DTD groups. Materials and Methods: We conducted a retrospective chart review study using data from Electronic Health Records (EHRs) of adult patients with psychiatric disorders followed by a CMHT from the Department of Psychiatry of the Coimbra Local Health Unit (between 1 December 2020-31 December 2022). The Dutch Measure for quantification of Treatment Resistance in Depression (DM-TRD) was used to assess the degree of treatment resistance and the Charlson Comorbidity Index (CCI) to measure medical comorbidity. Results: A quantity of 473 patients were referred to Cantanhede CMHT for a first assessment. Of these, 219 patients met the criteria for a primary diagnosis of any depressive disorder. Assistant psychiatrists identified 57 patients with DTD during follow-up (approximately 26%). The DTD group had higher rates of depressive episodes, greater depression severity, increased service use, higher DM-TRD scores, and a higher prevalence of comorbid anxiety symptoms, personality disorders, and severe medical comorbidities. The DTD group also had a higher prescription rate of antidepressants. Differences were observed in the use of antidepressant augmentation strategies and in the prescription of anticoagulant/antiplatelet drugs and analgesics, with higher prescription rates in the DTD group. We found correlations between DM-TRD and CCI scores, and between DM-TRD scores and all service use variables. Conclusions: Our results are consistent with a similar study in the United Kingdom, highlighting the need for a different approach to the management of DTD patients, who continue to live with a significant burden despite usual pharmacological and non-pharmacological treatments.

Research hotspots and trends in transcranial magnetic stimulation for cognitive impairment: A bibliometric analysis from 2014 to 2023

BACKGROUND

Cognitive impairment, which manifests as a limited deterioration of specific functions associated with a particular disease, can lead to a general deterioration of the patient’s standard of living. Transcranial magnetic stimulation, a non-invasive neuromodulation technique, is frequently employed to treat cognitive impairment in neuropsychiatric disorders.

AIM

To analyzed the state of international research on neuromodulation methods for treating cognitive impairment between 2014 and 2023, with the aim of exploring the state of research worldwide and the most recent developments in this particular area.

METHODS

Articles and reviews pertaining to neuromodulation methods for cognitive impairment were examined using the web of science database between January 2014 and December 2023. Publications, nations, organizations, writers, journals, citations, and keywords data from the identified studies were systematically analyzed using the CiteSpace 6.3. R1 software.

RESULTS

A total of 2371 documents with 11750 authors and 9461 institutions, with some co-occurrences, were retrieved. The quantity of yearly publications is showing an increasing trend. The United States and China have emerged as important contributors. Among the institutes, Harvard University had the highest number of publications, while Rossi S an author who is frequently cited. Initially, the primary keywords included human motor cortex, placebo-controlled trials, and serotonin reuptake inhibitors. However, the emphasis gradually moved to substance use disorders, supplementary motor areas, neural mechanisms, and exercise.

CONCLUSION

The use of neuromodulation techniques to treat cognitive impairment has drawn interest from academics all around the world. This study revealed hotspots and new trends in the research of transcranial magnetic stimulation as a cognitive impairment rehabilitation treatment. These findings are hold significant potential to guide further research and thus promote transcranial magnetic stimulation as a treatment method for cognitive impairment.

Evaluating Anesthesia Practices, Patient Characteristics, and Outcomes in Electroconvulsive Therapy: A Two-Year Retrospective Study

Background: Electroconvulsive therapy (ECT) is a well-established treatment for various psychiatric disorders. This retrospective study evaluates anesthesia practices, patient characteristics, and outcomes in ECT over a two-year period at the "Dr. Gheorghe Preda" Clinical Psychiatry Hospital in Sibiu, Romania. Methods: From March 2022 to July 2024, the Neuroscience Scientific Research Collective at our institution carried out a retrospective observational study on patients who underwent ECT. The evaluation and treatment protocol involved patients from all over the country. Results: The study involved 30 patients aged between 22 and 67 years and a mean age of 39.4 years; among them, 57% were male. The majority of the patients (68%) lived in urban areas, and 80% came from a different county. Schizophrenia was the most prevalent diagnosis (56.6%), followed by depression (40%) and bipolar disorder (3.4%). Common comorbidities included obesity/overweight, high blood pressure, and sinus tachycardia. A total of 330 ECT sessions were conducted, with an average of 11 sessions per patient, and 10 patients underwent multiple treatment courses. The reported adverse events included arterial hypertension, agitation, tachycardia, and shivering. Conclusions: This study underlines the safety and effectiveness of ECT when patients are closely monitored. Our results are consistent with the global data, suggesting that ECT is a good treatment option for severe psychiatric conditions with a manageable incidence of adverse events.

Treatment-resistant depression: molecular mechanisms and management

Due to the heterogeneous nature of depression, the underlying etiological mechanisms greatly differ among individuals, and there are no known subtype-specific biomarkers to serve as precise targets for therapeutic efficacy. The extensive research efforts over the past decades have not yielded much success, and the currently used first-line conventional antidepressants are still ineffective for close to 66% of patients. Most clinicians use trial-and-error treatment approaches, which seem beneficial to only a fraction of patients, with some eventually developing treatment resistance. Here, we review evidence from both preclinical and clinical studies on the pathogenesis of depression and antidepressant treatment response. We also discuss the efficacy of the currently used pharmacological and non-pharmacological approaches, as well as the novel emerging therapies. The review reveals that the underlying mechanisms in the pathogenesis of depression and antidepressant response, are not specific, but rather involve an interplay between various neurotransmitter systems, inflammatory mediators, stress, HPA axis dysregulation, genetics, and other psycho-neurophysiological factors. None of the current depression hypotheses sufficiently accounts for the interactional mechanisms involved in both its etiology and treatment response, which could partly explain the limited success in discovering efficacious antidepressant treatment. Effective management of treatment-resistant depression (TRD) requires targeting several interactional mechanisms, using subtype-specific and/or personalized therapeutic modalities, which could, for example, include multi-target pharmacotherapies in augmentation with psychotherapy and/or other non-pharmacological approaches. Future research guided by interaction mechanisms hypotheses could provide more insights into potential etiologies of TRD, precision biomarker targets, and efficacious therapeutic modalities.

Somatostatin: Linking Cognition and Alzheimer Disease to Therapeutic Targeting

Over 4 decades of research support the link between Alzheimer disease (AD) and somatostatin [somatotropin-releasing inhibitory factor (SRIF)]. SRIF and SRIF-expressing neurons play an essential role in brain function, modulating hippocampal activity and memory formation. Loss of SRIF and SRIF-expressing neurons in the brain rests at the center of a series of interdependent pathological events driven by amyloid-β peptide (Aβ), culminating in cognitive decline and dementia. The connection between the SRIF and AD further extends to the neuropsychiatric symptoms, seizure activity, and inflammation, whereas preclinical AD investigations show SRIF or SRIF receptor agonist administration capable of enhancing cognition. SRIF receptor subtype-4 activation in particular presents unique attributes, with the potential to mitigate learning and memory decline, reduce comorbid symptoms, and enhance enzymatic degradation of Aβ in the brain. Here, we review the links between SRIF and AD along with the therapeutic implications. SIGNIFICANCE STATEMENT: Somatostatin and somatostatin-expressing neurons in the brain are extensively involved in cognition. Loss of somatostatin and somatostatin-expressing neurons in Alzheimer disease rests at the center of a series of interdependent pathological events contributing to cognitive decline and dementia. Targeting somatostatin-mediated processes has significant therapeutic potential for the treatment of Alzheimer disease.

Estimating the benefit of esketamine nasal spray versus real-world treatment on patient-reported functional remission: results from the ICEBERG study

Introduction

Treatment resistant depression (TRD) affects approximately 10-30% of patients with major depressive disorder, and most patients with TRD do not respond to real-world treatments (RWT). Treatment with esketamine nasal spray (NS) plus a selective serotonin or serotonin norepinephrine reuptake inhibitor (SSRI/SNRI) has significant long-term clinical benefit over RWT in patients with TRD. However, the impact on patient-reported function remains to be determined.

Methods

The ICEBERG analysis was an indirect treatment comparison performed using data from two studies of patients with TRD: SUSTAIN-2 (esketamine NS; NCT02497287) and the European Observational TRD Cohort (EOTC; RWT; NCT03373253; clinicaltrials.gov). Here, patient-reported functional remission, assessed using the Sheehan Disability Scale (SDS), was defined as SDS ≤6 at Month 6. Analyses were conducted using propensity score re-weighting and multivariable models based on 18 covariates.

Results

At Month 6, the probability of functional remission in esketamine NS-treated patients from SUSTAIN-2 (n=512) was 25.6% (95% confidence interval [CI] 21.8-29.4), while the adjusted probability for RWT patients from the EOTC (n=184) was 11.5% (95% CI 6.9-16.1; relative risk: 2.226 [95% CI 1.451-3.416]; p=0.0003). In the total combined population (N=696), patients who did not achieve clinical response or remission had a low probability of achieving functional remission (5.84% and 8.76%, respectively). However, for patients who did achieve clinical response or remission, the probability of achieving functional remission was greater (43.38% and 54.15%, respectively), although many still did not achieve this status.

Conclusions

For patients with TRD, esketamine NS had a significant functional benefit versus RWT after 6 months of treatment. Irrespective of treatment, achievement of clinical response or remission was insufficient to attain functional remission. Nevertheless, clinical remission increased the likelihood of achieving functional remission, further supporting an important role for clinical remission in for the path towards functional recovery.

Targeting Method for rTMS for Treating Depression in Japanese Patients: A Comparison of the Standard, F3, and Neuronavigation Approaches

INTRODUCTION

The left dorsolateral prefrontal cortex (lDLPFC) is a commonly targeted brain region for repetitive transcranial magnetic stimulation (rTMS) for depression. The lDLPFC has been identified using the "5-cm rule." However, identification of the lDLPFC may deviate from the ideal stimulation site localized by neuronavigation. Therefore, we aimed to compare this method with other methods and examine the relationship between deviation from the ideal stimulation site and treatment effects. While most existing studies have focused on participants of European descent, this study focused on Japanese participants.

METHODS

The study participants were 16 patients who underwent rTMS and had the stimulus location identified using the 5-cm method. The lDLPFC was identified by the F3 electrode position and neuronavigation in addition to the 5-cm rule, and these locations were compared. We then performed a correlation analysis of the distance between the sites identified by the 5-cm method and by neuronavigation, as well as changes in scores on the 17-item Hamilton Depression Scale (HAMD-17).

RESULTS

The lDLPFC identified by the F3 site and neuronavigation was approximately 3 cm more anterolateral than that identified by the 5-cm method. A significant correlation was found between the distance between the sites identified by the 5-cm method and neuronavigation and the rate of change in HAMD-17 scores.

CONCLUSION

The ideal stimulation site may be approximately 3 cm anterior to the site identified by the 5-cm method, and stimulation of the F3 site may be a valid alternative to the 5-cm method.

Balancing Evidence and Need: Variation in US Commercial Payer Coverage of Esketamine

PURPOSE

Variations in US commercial health plan coverage policies affect how patients access medications. Plans may vary in treatment access criteria, line of therapy, and prescriber requirements. In this study, we examined coverage of esketamine hydrochloride (Spravato) for major depressive disorder (MDD) and treatment-resistant depression (TRD) to answer the following question: how do US commercial health plans cover esketamine, and how do they guide prompt patient access to the drug?

METHODS

We used information from the Tufts Medical Center Specialty Drug Evidence and Coverage database, which includes coverage policies issued by 18 large commercial health plans in the United States. Esketamine coverage policies for MDD and TRD active in December 2022 were collated and analyzed. We compared coverage policies according to step therapy protocols, patient subgroup restrictions, and prescriber requirement criteria, evaluating patient access using the number of restrictions and proportion of plans including each criterion.

FINDINGS

Plans more often imposed step therapy requirements for access to esketamine for TRD than for MDD, with line of treatment of ≤9 steps for MDD compared with 1 to 5 steps for TRD. Plans also varied with respect to the therapies they required patients to first try and experience treatment failure before granting access to esketamine for both indications. Clinical coverage requirements varied in thresholds and rating scales used to assess severity of depressive symptoms.

IMPLICATIONS

Plans vary in terms of line of therapy and clinical coverage requirements for access to esketamine. Variation in health plan coverage policies may result in inequitable access and added complexity for patients and clinicians navigating care, which may delay access to urgent treatment.

CLINICALTRIALS

GOV IDENTIFIERS

Not applicable.

Comparative Side-Effects of Neurosurgical Treatment of Treatment-Resistant Depression

INTRODUCTION

Treatment-resistant depression (TRD) is a condition in which patients suffering from depression no longer respond to common methods of treatment, such as anti-depressant medication. Neurosurgical procedures such as ablative surgery, deep brain stimulation, and vagus nerve stimulation have been used in efforts to overcome TRD.

OBJECTIVES

This review aims to provide an overview of the side effects of neurosurgery performed in clinical studies related to depression.

METHODS

A literature search was conducted through PubMed, MEDLINE, EMBASE, Ovid, and ClinicalTrials.gov databases.

RESULTS

This review selected 10 studies for ablative surgery, 12 for deep brain stimulation, and 10 for vagus nerve stimulation, analyzing their side effect profiles of neurosurgery for TRD. The major side effects of each type of neurosurgery were identified, such as incontinence and confusion for ablative surgery, headaches and increased suicide ideation for deep brain stimulation, and voice hoarseness and dyspnea for vagus nerve stimulation.

CONCLUSION

The review discusses the merits and demerits of neurosurgery as a treatment option for TRD. It also suggests new insights into decreasing the burden of these neurosurgical side effects so that they can be a viable, high-efficacy treatment method for TRD.

Peer-led intervention for individuals with major depression: study protocol for a randomized controlled trial (SUPEERMood)

BACKGROUND

Major Depressive Disorder (MDD) is one of the most disabling mental health problems worldwide. The Recovery Model emphasizes peer support to empower individuals with MDD, improve self-management, and patients' quality of life. Despite the demonstrated efficacy of peer-led interventions, further research is needed due to methodological limitations and variability in interventions across studies. Therefore, the objective of this trial is to evaluate the effectiveness of an adjuvant peer-led intervention for the reduction of depressive symptoms in individuals diagnosed with MDD attended in primary care mental health units.

METHODS

A controlled, parallel, randomized clinical trial will be conducted. The intervention group (n = 35) will receive 6 weeks of peer-led sessions based on a peer support program drive whilst supervised by nurses, while the control group (n = 35) will use a mobile Health (mHealth) application for emotional wellness based on CBT for 6 weeks. Measurements will be collected at baseline, at 6 weeks, at 6 and 12 months after the intervention to evaluate post-intervention effects. The primary outcome is the reduction of depressive symptoms through the Beck Depression Inventory (BDI-II) after the intervention. Secondary outcomes will involve measures such as adherence to psychiatric treatment, quality of life, adherence to mediterranean diet, alcohol consumption and physical activity.

DISCUSSION

We hypothesize that this peer-led intervention, in contrast to the mHealth, will show improvement in BDI-II score reduction of 6 points after six weeks, 6 and 12 months. Standardized peer-led programs can benefit patients and professionals in terms of efficacy and feasibility of clinical treatment of depression, healthy habits, self-care and quality of life. In addition, they can provide recovery and relapse reduction, improved psychosocial support, minimization of intensive care use, and support for patient autonomy through self-management.

TRIAL REGISTRATION

The trial protocol is prospectively registered with ClinicalTrials.gov under protocol registration number NCT06398561. Date of registration: May 01, 2024. Recruitment is ongoing.

Predictors of response to accelerated rTMS in the treatment of treatment-resistant depression

Accelerated repetitive transcranial magnetic stimulation (rTMS) is a promising treatment for treatment-resistant depression (TRD). We aimed to investigate the existence of clinical predictive factors in response to accelerated rTMS in the treatment of TRD. In total, 119 TRD patients who received accelerated rTMS were included in this study. The stimulation protocol was 15 Hz stimulation over the the left dorsolateral prefrontal cortex. The protocol consisted of 25 sessions, each session lasting 30 min for a total of 3000 pulses. Five sessions were applied per day for 5 consecutive days. At baseline (T0), day 5 (immediately after treatment) (T1), 4 weeks after treatment (T2), depression severity was evaluated using the 17-item Hamilton Depression Rating Scale (HAMD-17), cognitive function was evaluated using Wisconsin Card Sorting Test (WCST), the intensity of suicidal ideation was evaluated using the Columbia-Suicide Severity Rating Scale (C-SSRS). Systemic immune-inflammation index (SII) was calculated at T0 and T2. The HAMD-17 scores, WCST performance, the C-SSRS scores at T1 and T2 were improved from T0 (P < 0.01). The SII at T2 was lower than at T0 (P < 0.01). The response rates at T1 and T2 were 57.98% (69/119) and 48.74% (58/119), respectively. The results of binary logistic analysis showed that shorter course of depression, two failed antidepressant trials, no history of ECT treatment, and lower levels of SII were predictive factors for accelerated rTMS treatment response at T1 and T2 (P < 0.05), while not having a history of hospitalization was a predictive factor for response at T2 (P < 0.05) but not at T1 (P > 0.05). Based on ROC curve analysis, the optimal cut-off values of SII for discriminating responders from non-responders at T1 and T2 were < 478.56 and < 485.03, respectively. The AUC of SII at T0 predicting response for T1 and T2 were 0.729 and 0.797. We found several clinical predictors of better responses to the accelerated rTMS. Identifying clinical predictors of response is relevant to personalize and adapt rTMS protocols in TRD patients.

Understanding profiles of patients with treatment-resistant depression by stringency of health plan prior authorization criteria for approval of esketamine nasal spray

OBJECTIVES

In the United States (US), prescription drug coverage is subject to prior authorization (PA) criteria, which may vary between health plans and may exceed drug label requirements. This study aimed to characterize profiles and treatment history of patients with treatment-resistant depression (TRD) who initiated esketamine nasal spray, by stringency of their health plans' PA criteria relative to the esketamine label.

METHODS

Adults with evidence of TRD (≥2 antidepressant courses of adequate dose and duration) prior to initiating esketamine were identified using US insurance claims data (03/2016-02/2022). Based on health plan PA criteria for esketamine obtained from Managed Markets Insight & Technology data (05/2020-02/2022), patients were grouped into stringent (PA criteria exceeds label) and non-stringent (PA criteria less stringent or equal to label) cohorts. Patient treatment history before esketamine initiation was compared using Wilcoxon rank sum and Fisher's exact tests.

RESULTS

The stringent cohort included 168 patients (mean age: 45 years, 63% female) and the non-stringent cohort included 400 patients (mean age: 45 years, 70% female). During the ongoing major depressive episode before esketamine initiation, the stringent versus non-stringent cohort completed 3.9 versus 3.8 antidepressant treatment courses, on average (p = 0.217); 94.6% versus 96.8% used augmentation therapy (p = 0.240), including 59.3% versus 58.1% with an antipsychotic (p = 0.844), respectively.

CONCLUSIONS

Regardless of health plan stringency, on average, patients exceeded US label-mandated number of antidepressant trials before esketamine initiation, which questions the need for health insurance plans PA criteria above label.

The effect of mindfulness meditation on depressive symptoms during the COVID-19 pandemic: a systematic review and meta-analysis

Currently, 280 million people worldwide experience depression, ranking it third in the global burden of disease. The incidence of depression has risen due to the COVID-19 pandemic, making it essential to examine evidence-based practices in reducing depressive symptoms during this unprecedented time. This systematic review and meta-analysis aim to analyze randomized controlled trials during the COVID-19 pandemic that evaluated the effect of mindfulness meditation on depressive symptoms in individuals with depression. Four databases (PubMed, Embase, Web of Science, and Scopus) were searched in November 2023 using search terms including meditation, mindfulness, depression, and depressive symptoms. The meta-analysis was conducted using Review Manager 5.4 software (Cochrane Collaboration). A random model and Standard Mean Difference analysis with 95% CIs were used for continuous variables. The systematic review included 26 RCT studies. The meta-analysis showed significant effects of mindfulness meditation interventions (SMD = - 1.14; 95% CI - 1.45 to - 0.83; P < 0.001) in reducing depressive symptoms compared to comparison groups. The findings suggest a positive effect of mindfulness meditation on depressive symptoms in individuals with depression during the COVID-19 pandemic.

Case report: Personalizing the use of trazodone in real-world patients: a study of three cases of depression with comorbidities

Depressive disorders are leading contributors to the global mental health-related burden, and they represent a challenge for real-world clinicians, due to the low rates of remission despite the high availability of treatments. Often, depression shows in the context of multiple chronic comorbidities, thus requiring precise and accurate management of pharmacological treatments to avoid interactions and side effects. These criticalities call for the need for new strategies of treatment, which may include new insights into the pharmacological properties of currently available antidepressant drugs, to enhance their efficacy in the different contexts in which depression may arise. Trazodone is the prototype serotonin antagonist/reuptake inhibitor antidepressant (SARI). Due to the malleability granted by its multiple formulations, trazodone is frequently used to treat depression, both as an add-on to other antidepressants and as a monotherapy, with satisfying results. Moreover, its tolerability makes it one of the most prescribed antidepressants in patients with poly-treated comorbid medical illnesses, especially in the elderly. Herein, a case series is presented regarding the use of trazodone in patients with complex comorbid diagnoses or distressing side effects. Each of the three cases has been discussed in three specific Round Tables, involving expert clinicians in the fields of Psychiatry, Neurology, General Practice, and Geriatrics using the Nominal Group Technique. The ideas collected have been used to integrate the cases and the discussion with the intent of facilitating accessibility to the widest audience of physicians and clinical workers in different clinical practice contexts. The final aim of this paper is to promote an increasingly personalized use of trazodone in real-world patients with depression.

A systematic review and meta-analysis of the preclinical and clinical results of low-field magnetic stimulation in cognitive disorders

Cognitive disorders such as major depressive disorder and bipolar disorder severely compromise brain function and neuronal activity. Treatments to restore cognitive abilities can have severe side effects due to their intense and excitatory nature, in addition to the fact that they are expensive and invasive. Low-field magnetic stimulation (LFMS) is a novel non-invasive proposed treatment for cognitive disorders. It repairs issues in the brain by altering deep cortical areas with treatments of low-intensity magnetic stimulation. This paper aims to summarize the current literature on the effects and results of LFMS in cognitive disorders. We developed a search strategy to identify relevant studies utilizing LFMS and systematically searched eight scientific databases. Our review suggests that LFMS could be a viable and effective treatment for multiple cognitive disorders, especially major depressive disorder. Additionally, longer, more frequent, and more personalized LFMS treatments tend to be more efficacious.

Pain-Insomnia-Depression Syndrome: Triangular Relationships, Pathobiological Correlations, Current Treatment Modalities, and Future Direction

Pain-insomnia-depression syndrome (PIDS) is a complex triad of chronic pain, insomnia, and depression that has profound effects on an individual's quality of life and mental health. The pathobiological context of PIDS involves complex neurobiological and physiological mechanisms, including alterations in neurotransmitter systems and impaired pain processing pathways. The first-line therapeutic approaches for the treatment of chronic pain, depression, and insomnia are a combination of pharmacological and non-pharmacological therapies. In cases where patients do not respond adequately to these treatments, additional interventions such as deep brain stimulation (DBS) may be required. Despite advances in understanding and treatment, there are still gaps in knowledge that need to be addressed. To improve our understanding, future research should focus on conducting longitudinal studies to uncover temporal associations, identify biomarkers and genetic markers associated with PIDS, examine the influence of psychosocial factors on treatment responses, and develop innovative interventions that address the complex nature of PIDS. The aim of this study is to provide a comprehensive overview of these components and to discuss their underlying pathobiological relationships.

Safety and tolerability of esketamine nasal spray versus quetiapine extended release in patients with treatment resistant depression

In ESCAPE-TRD (NCT04338321), esketamine nasal spray (NS) significantly increased the probability of remission at Week 8, and of being relapse-free through Week 32 after remission at Week 8, versus quetiapine extended release (XR) in patients with treatment resistant depression (TRD). Here, we explore the time course, burden and consequences of treatment emergent adverse events (TEAEs) in the phase IIIb ESCAPE‑TRD trial. Patients with TRD were randomised 1:1 to esketamine NS or quetiapine XR, dosed per label alongside an ongoing selective serotonin reuptake inhibitor/serotonin norepinephrine reuptake inhibitor. In this secondary publication, safety analyses (comprising patients who received ≥1 dose of study treatment) included incidence, severity and durations (Kaplan‑Meier method) of TEAEs, and subsequent dispositional changes. P values were not adjusted for multiple testing. 336 patients were randomised to esketamine NS and 340 to quetiapine XR; 334 and 336 received ≥1 dose of study treatment, respectively. TEAEs were significantly more common with esketamine NS than quetiapine XR (91.9 % versus 78.0 %; p < 0.001), but were typically mild/moderate and transient in nature: a greater proportion resolved on the same-day (92.0 % versus 12.1 %) and lead to treatment discontinuation in significantly fewer patients (4.2 % versus 11.0 %, respectively; p < 0.001). The proportion of days spent with TEAEs was significantly lower with esketamine NS than quetiapine XR (median: 11.9 % versus 21.3 %; p < 0.001). Although more frequent with esketamine NS, TEAEs were typically transient and mild, with discontinuation less likely versus quetiapine XR. Data were consistent with established safety profiles, with no new safety signals identified. Alongside greater efficacy, the demonstrably more favourable tolerability profile of esketamine NS versus quetiapine XR further supports its use for TRD.

Real-world case series of maintenance theta burst stimulation therapy following response to acute theta burst stimulation therapy for difficult-to-treat depression

OBJECTIVE

Treatment and management for difficult-to-treat depression are challenging, especially in a subset of patients who are at high risk for relapse and recurrence. The conditions that represent this subset are recurrent depressive disorder (RDD) and bipolar disorder (BD). In this context, we aimed to examine the effectiveness of maintenance transcranial magnetic stimulation (TMS) on a real-world clinical basis by retrospectively extracting data from the TMS registry data in Tokyo, Japan.

METHODS

Data on patients diagnosed with treatment-resistant RDD and BD who received maintenance intermittent theta burst stimulation (iTBS) weekly after successful treatment with acute iTBS between March 2020 and October 2023 were extracted from the registry.

RESULTS

All patients (21 cases: 10 cases with RDD and 11 cases with BD) could sustain response, and 19 of them further maintained remission. In this study, maintenance iTBS did not exacerbate depressive symptoms in any of the cases, but may rather have the effect of stabilizing the mental condition and preventing recurrence.

CONCLUSIONS

This case series is of great clinical significance because it is the first study to report on the effectiveness of maintenance iTBS for RDD and BD, with a follow-up of more than 2 years. Further validation with a randomized controlled trial design with a larger sample size is warranted.

Enzymatic biomarkers of oxidative stress in patients with depressive disorders. A systematic review

Oxidative stress (OS) results from the imbalance between the production of reactive oxygen species and the body's antioxidant mechanisms and is associated with various diseases, including depression. Antioxidants protect cells by neutralizing free radicals and include enzymatic components such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), and glutathione S-transferase (GST). The concentration of these biomarkers can quantify OS. This research aimed to gather available information published in the last ten years about the concentration of enzymatic OS biomarkers in samples from patients with depressive disorders.

METHOD

A systematic review was conducted following the PRISMA guidelines, including original scientific articles that evaluated enzymatic OS biomarkers in participants with depressive disorders, using the keywords and boolean operators "superoxide dismutase" OR "catalase" OR "glutathione" AND "depress*" in the databases PubMed, SAGE Journals, DOAJ, Scielo, Dialnet, and Redalyc.

RESULTS

The initial search showed 614 results, with only 28 articles meeting the selection criteria. It was observed that all evaluated oxidative stress enzymatic markers showed a significant increase or decrease in patients with depressive disorders, due to a wide variability in the depressive disorders studied, the type of biological sample analyzed, and the techniques used.

CONCLUSION

There is evidence of the relationship between enzymatic OS biomarkers and depressive disorders, but additional studies are needed to clarify the nature of this relationship, particularly considering the different types of depressive disorders.

Repurposing General Anesthetic Drugs to Treat Depression: A New Frontier for Anesthesiologists in Neuropsychiatric Care

During the last 100 years, the role of anesthesiologists in psychiatry has focused primarily on facilitating electroconvulsive therapy and mitigating postoperative delirium and other perioperative neurocognitive disorders. The discovery of the rapid and sustained antidepressant properties of ketamine, and early results suggesting that other general anesthetic drugs (including nitrous oxide, propofol, and isoflurane) have antidepressant properties, has positioned anesthesiologists at a new frontier in the treatment of neuropsychiatric disorders. Moreover, shared interest in understanding the biologic underpinnings of anesthetic drugs as psychotropic agents is eroding traditional academic boundaries between anesthesiology and psychiatry. This article presents a brief overview of anesthetic drugs as novel antidepressants and identifies promising future candidates for the treatment of depression. The authors issue a call to action and outline strategies to foster collaborations between anesthesiologists and psychiatrists as they work toward the common goals of repurposing anesthetic drugs as antidepressants and addressing mood disorders in surgical patients.