A Review of the Conceptualisation and Risk Factors Associated with Treatment-Resistant Depression

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).

Antidepressant-like effects of the leaf extract of Mallotus oppositifolius (Geiseler) Müll. Arg. (Euphorbiaceae) in the chronic unpredictable mild stress model: A role of the gut-brain axis

The gut microbiota has been posited as a target for the treatment of major depressive disorder. Herein, we investigated the effect of the hydroethanolic leaf extract of Mallotus oppositifolius (MOE) on the gut microbiota of mice and how this contributes to its known antidepressant-like effect. A 6-week chronic unpredictable mild stress (CUMS) procedure was employed in 7 groups of mice to induce depression. From the third week, oral MOE treatments (10, 30, 100 mg/kg) and two reference drugs, fluoxetine (12 mg/kg) and minocycline (40 mg/kg), known to affect the gut microbiota, were administered. The sixth and seventh groups were the vehicle stressed (VEH-S) and non-stressed groups (VEH-NS). Changes in depressive-like behaviors were assessed using sucrose preference test while the forced swimming test (FST) was used to assess sustained antidepressant-effect after treatment discontinuation. Moreover, changes in prefrontal cortex (PFC) and hippocampal serotonin (5-HT) levels were evaluated using enzyme-linked immunosorbent assay (ELISA). The effect of treatment on the profile of the gut microbiota of the groups was elucidated using 16S rRNA Oxford Nanopore sequencing. MOE and reference drugs reversed the depression-associated reduction in sucrose preference when compared to VEH-S. MOE (with peak effect at 30 mg/kg) reduced immobility while increasing swimming and climbing behaviors. MOE reversed CUMS-induced reduction of 5-HT concentration in PFC and hippocampus. The behavioral effects of MOE were associated with shifts in the gut microbiota of CUMS-exposed mice. The study has provided seminal evidence that MOE ameliorates CUMS-induced depressive symptoms by modulating gut microbiota and increasing brain 5-HT levels.

Exploring the role of affective temperaments: predicting major depressive disorder in the context of borderline personality disorder

PURPOSE

Major depressive disorder (MDD) is a complex condition believed to arise from a multifaceted interplay of genetic, environmental, and biological factors. In the pursuit of understanding its etiology, two elements that warrant investigation are borderline personality disorder (BPD) and affective temperaments. We aim to gain deeper insights into the mechanisms underlying this debilitating mental health condition.

METHOD

The dataset comprises individuals who sought assistance from psychiatry outpatient clinics for diverse reasons during the period spanning from 2018 to 2022. These individuals underwent SCID-II assessments to diagnose borderline personality disorder (BPD) and also completed the TEMPS-A temperament tests.

RESULTS

The mean years of schooling was lower in the MDD group (p = 0.014). Two groups are compared in terms of affective temperament. Depressive (p < 0.0001), cyclothymic (p < 0.0001), anxious (p = 0.001), and irritable (p < 0.0001) temperament scores were statistically higher in the MDD group. Apart from the scale scores, the prevalence of affective temperament was evaluated and the same temperaments (depressive (p < 0.0001), cyclothymic (p < 0.0001), anxious (p = 0.001), and irritable (p < 0.0001)) were found to be significantly higher in the MDD group. Diagnosis of BPD is higher in the MDD group (p = 0.002). Binary logistic regression analysis revealed that the presence of cyclothymic temperament and marital status may be predictor factors for the development of MDD (p < 0.0001, CI: 0.001-0.121 and p = 0.002, CI: 1.550-7.172, respectively).

CONCLUSION

Notably, higher scores in cyclothymic temperament and experiencing loneliness have been identified as significantly associated with MDD. Interestingly, in patients with comorbid BPD-MDD, the presence of cyclothymic temperament appears to be a more critical factor than personality traits. This finding underscores the potential role of cyclothymic temperament in contributing to the co-occurrence of BPD and MDD.

Facts and myths about use of esketamine for treatment-resistant depression: a narrative clinical review

Introduction and aims

Treatment-resistant depression (TRD) occurs when at least two different antidepressants, taken at the right dosage, for adequate period of time and with continuity, fail to give positive clinical effects. Esketamine, the S-enantiomer of ketamine, was recently approved for TRD treatment from U.S. Food and Drug Administration and European Medicine Agency. Despite proved clinical efficacy, many misconceptions by clinicians and patients accompany this medication. We aimed to review the most common "false myths" regarding TRD and esketemine, counterarguing with evidence-based facts.

Methods

The keywords "esketamine", "treatment resistance depression", "depression", "myth", "mythology", "pharmacological treatment", and "misunderstanding" were entered in the main databases and combined through Boolean operators.

Results

Misconceptions regarding the TRD prevalence, clinical features and predictors have been found. With respect of esketamine, criteria to start treatment, dissociative symptoms, potential addiction and aspects of administration and monitoring, were found to be affected by false beliefs by clinicians and patients.

Discussion and conclusion

TRD represents a challenging condition, requiring precise diagnosis in order to achieve patient's full recovery. Esketamine has been proved as an effective medication to treat TRD, although it requires precautions. Evidence can inform clinical practice, in order to offer this innovative treatment to all patients with TRD.

[Clinical management of treatment-resistant depression]

Treatment-resistant depression (TRD) is a complex disorder. Although no standardized definition has been established to date, there are promising and well-established treatment options for the condition. Looking at the current pharmacological and neuromodulatory strategies, there is an urgent need for fast-acting and well-tolerated treatment options. The search for new mechanisms of action goes beyond the monoamine hypothesis. For example, esketamine is already an established treatment method that is fast-acting and well tolerated, while psychedelics or esmethadone are currently still undergoing clinical trials. Compounds that can be used off-label, such as dextromethorphan or anti-inflammatory strategies are also presented. Pharmacological approaches that focus on the modulation of the glutamatergic system or belong to the class of psychedelics, appear to be of particular importance for current research and development. These particularly include substances that rapidly exert clinical effects and have a favorable side-effect profile.

Biological correlates of treatment resistant depression: a review of peripheral biomarkers

Introduction

Many patients fail to respond to multiple antidepressant interventions, being defined as "treatment-resistant depression" (TRD) patients. TRD is usually associated with increased severity and chronicity of symptoms, increased risk of comorbidity, and higher suicide rates, which make the clinical management challenging. Efforts to distinguish between TRD patients and those who will respond to treatment have been unfruitful so far. Several studies have tried to identify the biological, psychopathological, and psychosocial correlates of depression, with particular attention to the inflammatory system. In this paper we aim to review available studies assessing the full range of biomarkers in TRD patients in order to reshape TRD definition and improve its diagnosis, treatment, and prognosis.

Methods

We searched the most relevant medical databases and included studies reporting original data on possible biomarkers of TRD. The keywords "treatment resistant depression" or "TRD" matched with "biomarker," "inflammation," "hormone," "cytokine" or "biological marker" were entered in PubMed, ISI Web of Knowledge and SCOPUS databases. Articles were included if they included a comparison with healthy controls (HC).

Results

Of the 1878 papers identified, 35 were included in the present study. Higher plasma levels of IL-6 and TNF-α were detected in TRD patients compared to HC. While only a few studies on cortisol have been found, four papers showed elevated levels of C-reactive protein among these patients and four articles focused on immunological cells. Altered kynurenine metabolism in TRD patients was reported in two studies, while contrasting results were found with regard to BDNF.

Conclusion

Only a few biological alterations correlate with TRD. TNF-α seems to be the most relevant biomarker to discriminate TRD patients from both HC and treatment-responsive MDD patients. Moreover, several discrepancies among studies have been found, due to methodological differences and the lack of a standardized diagnostic definition of TRD.

Machine learning prediction will be part of future treatment of depression

Machine learning (ML) is changing the way that medicine is practiced. While already clinically utilised in diagnostic radiology and outcome prediction in intensive care unit, ML approaches in psychiatry remain nascent. Implementing ML algorithms in psychiatry, particularly in the treatment of depression, is significantly more challenging than other areas of medicine in part because of the less demarcated disease nosology and greater variability in practice. Given the current exiguous capacity of clinicians to predict patient and treatment outcomes in depression, there is a significantly greater need for better predictive capability. Early studies have shown promising results. ML predictions were significantly better than chance within the sequenced treatment alternatives to relieve depression (STAR*D) trial (accuracy 64.6%, p < 0.0001) and combining medications to enhance depression outcomes (COMED) randomised Controlled Trial (RCT) (accuracy 59.6%, p = 0.043), with similar results found in larger scale, retrospective studies. The greater flexibility and dimensionality of ML approaches has been demonstrated in studies incorporating diverse input variables including electroencephalography scans, achieving 88% accuracy for treatment response, and cognitive test scores, achieving up to 72% accuracy for treatment response. The predicting response to depression treatment (PReDicT) trial tested ML informed prescribing of antidepressants against standard therapy and found there was both better outcomes for anxiety and functional endpoints despite the algorithm only having a balanced accuracy of 57.5%. Impeding the progress of ML algorithms in psychiatry are pragmatic hurdles, including accuracy, expense, acceptability and comprehensibility, and ethical hurdles, including medicolegal liability, clinical autonomy and data privacy. Notwithstanding impediments, it is clear that ML prediction algorithms will be part of depression treatment in the future and clinicians should be prepared for their arrival.

Structural and functional features of treatment-resistant depression: A systematic review and exploratory coordinate-based meta-analysis of neuroimaging studies

OBJECTIVES

A third of people suffering from major depressive disorder do not experience a significant improvement in their symptoms even after adequate treatment with two different antidepressant medications. This common condition, termed treatment-resistant depression (TRD), severely affects the quality of life of millions of people worldwide, causing long-lasting interpersonal problems and social costs. Given its epidemiological and clinical relevance and the little consensus on whether the neurobiological underpinnings of TRD differ from treatment-sensitive depression (TSD), we sought to highlight the convergent morphometric and functional neuroimaging correlates of TRD.

METHODS

We systematically reviewed the published literature on structural and resting-state functional neuroimaging of TRD compared to TSD and healthy controls (HC) and performed exploratory coordinate-based meta-analyses (CBMA) of significant results separately for each modality and multimodally ("all-effects"). CBMAs were also performed for each direction and combining both directions of group contrasts.

RESULTS

Out of the initial 1929 studies, only eight involving 555 participants (189 patients with TRD, 156 with TSD, and 210 HC) were included. In all-effects CBMA, precentral/superior frontal gyrus showed a significant difference between TRD and HC. Functional and structural imaging meta-analyses did not yield statistically significant results. A marginally significant cluster of altered intrinsic activity was found between TRD and HC in the cerebellum/pons.

CONCLUSIONS

Frontal, cerebellar, and brainstem functions can be involved in the pathophysiology of TRD. However, the design and heterogeneity of the (scarce) published literature hinder the generalizability of the findings.

The update of self-identity: Importance of assessing autobiographical memory in major depressive disorder

Major depressive disorder is a leading global cause of disability. There is a growing interest for memory in mood disorders since it might constitute an original tool for prevention, diagnosis, and treatment. MDD is associated with impaired autobiographical memory characterized by a tendency to overgeneral memory, rather than vivid episodic self-defining memory, which is mandatory for problem-solving and projection in the future. This memory bias is maintained by three mechanisms: ruminations, avoidance, and impaired executive control. If we adopt a broader and comprehensive perspective, we can hypothesize that all those alterations have the potential to impair self-identity updating. We posit that this update requires a double referencing process: (1) to internalized self-representation and (2) to an externalized framework dealing with the representation of the consequence of actions. Diagnostic and therapeutic implications are discussed in the light of this model and the importance of assessing autobiographical memory in MDD is highlighted. This article is categorized under: Psychology > Memory Psychology > Brain Function and Dysfunction Neuroscience > Clinical.

Association of Treatment-Resistant Depression With Patient Outcomes and Health Care Resource Utilization in a Population-Wide Study

Importance

The totality of the societal and individual impact of treatment-resistant depression (TRD) is unknown, as is the potential to prognosticate TRD. The generalizability of many observational studies on TRD is limited.

Objective

To estimate the burden of TRD in a large population-wide cohort in an area with universal health care by including data from both health care types (psychiatric and nonpsychiatric) and, further, to develop a prognostic model for clinical use.

Design, Setting, and Participants

This cohort study, a population-based observational study, assessed data from the Stockholm MDD Cohort for episodes of major depressive disorder (MDD) between 2010 and 2017 that fulfilled predefined criteria for TRD (≥3 consecutive antidepressant treatments). Data analysis was performed from August 2020 to May 2022.

Main Outcomes and Measures

Outcomes were psychiatric and nonpsychiatric comorbid conditions, antidepressant treatments, health care resource utilization, lost workdays, all-cause mortality, and intentional self-harm and, in the prognostic model, TRD.

Results

A total of 158 169 unipolar MDD episodes (in 145 577 patients) were identified between January 1, 2012, and December 31, 2017 (64.7% women; median [IQR] age, 42 years [30-56]). Of these, 12 793 episodes (11%) fulfilled criteria for TRD. The median (IQR) time from the start of MDD episode to TRD was 552 days (294-932). Selective serotonin reuptake inhibitor was the most common class of antidepressant treatment in all treatment steps, and 5907 patients (46.2%) received psychotherapy at some point before initiation of the third pharmacological antidepressant treatment. Compared with matched non-TRD episodes, TRD episodes had more inpatient bed-days (mean, 3.9 days; 95% CI, 3.6-4.1, vs 1.3 days; 95% CI, 1.2-1.4) and more lost workdays (mean, 132.3 days; 95% CI, 129.5-135.1, vs 58.7 days; 95% CI, 56.8-60.6) 12 months after the index date. Anxiety, stress, sleep disorder, and substance use disorder were all more common comorbid conditions in TRD episodes. Intentional self-harm was more than 4 times more common in TRD episodes. The all-cause mortality rate for patients with MDD with TRD episodes was 10.7/1000 person-years at risk, compared with 8.7/1000 person-years at risk for patients with MDD without TRD episodes (hazard ratio, 1.23; 95% CI, 1.07-1.41). Median time from start of the first antidepressant treatment to start of the second, and from start of the second antidepressant treatment to start of the third, was 165 and 197 days, respectively. The severity of MDD, defined using the self-rating Montgomery-Åsberg Depression Rating Scale (MADRS-S) at time of MDD diagnosis, was found to be the most important prognostic factor for TRD (C index = 0.69).

Conclusions and Relevance

In this cohort study, TRD was a common variant of MDD when including patients from both health care types, which is associated with a high disease burden for both patients and society. The median time between initiation of new antidepressant treatments was longer than recommended in current treatment guidelines, suggesting room for more structured and timely depression care.

The Effectiveness of Mindful Hypnotherapy on Depression, Self-Compassion, and Psychological Inflexibility in Females with Major Depressive Disorder: A Single-Blind, Randomized Clinical Trial

The effectiveness of the novel intervention mindful hypnotherapy on depression, self-compassion, and psychological inflexibility in females with major depressive disorder was examined in a randomized, clinical trial. Thirty-four participants were randomly allocated into mindful hypnotherapy and waitlist control groups. The intervention group was treated in 8 face-to-face, 60-minute weekly therapy sessions along with mindful hypnosis audio tapes to be used daily. The results of analysis of covariance indicated that there were significant differences between the mindful hypnotherapy and waitlist control groups after intervention and at 2-month follow-up (p < .001). The between-subject test of repeated measures ANOVAs also indicated a clinically significant difference between groups across time (baseline, postintervention, and 2-month follow-up) in depression, F = 53.86, p < .001, effect size = .65, and in self-compassion, F = 33.18, p < .001, effect size = .53, as well as psychological inflexibility, F = 26.84, p < .001, effect size = .48. In conclusion, this study indicates that mindful hypnotherapy is an effective intervention for treating depression as well as reducing psychological inflexibility and improving self-compassion for patients with major depressive disorder.

Transcutaneous auricular vagus nerve immediate stimulation treatment for treatment-resistant depression: A functional magnetic resonance imaging study

Objective

Transcutaneous auricular vagus nerve stimulation (taVNS) is effective for treatment-resistant depression (TRD). In the current study, we observed the immediate modulating brain effect of taVNS in patients with TRD using rest-state functional magnetic resonance imaging (rs-fMRI).

Method

Forty patients with TRD and forty healthy controls (HCs) were recruited. Rs-fMRI was performed before and after 30 min of taVNS at baseline. The brain regions that presented significantly different the Regional Homogeneity (ReHo) between the TRD patients and HCs were selected as the ROI to calculate the functional connectivity (FC) of full brain. The correlations were estimated between the clinical scales' score and the functional brain changes.

Results

Following taVNS stimulation treatment, TRD patients showed significantly reduced ReHo in the medial orbital frontal cortex (mOFC) (F = 18.06, P < 0.0001), ANCOVA of the mOFC-Based FC images revealed a significant interaction effect on the left inferior parietal gyrus (IPG) and left superior marginal gyrus (SMG) (F = 11.6615, P<0.001,F = 16.7520, P<0.0001). Among these regions, the HAMD and HAMA scores and ReHo/FC changes were not correlated.

Conclusion

This study applied rs-fMRI technology to examine the effect of taVNS stimulation treatment on the brain activity of TRD. These results suggest that the brain response of TRD patients to taVNS treatment may be associated with the functional modulation of cortical regions including the medial orbital frontal cortex, the left inferior parietal gyrus, and the left superior marginal regions. Changes in these neuroimaging indices may represent the neural mechanisms underlying taVNS Immediate Stimulation treatment in TRD.

Recognizing the importance of childhood maltreatment as a critical factor in psychiatric diagnoses, treatment, research, prevention, and education

Childhood maltreatment is the most important preventable risk factor for psychiatric disorders. Maltreated individuals typically develop psychiatric disorders at an earlier age, have a more pernicious course, more comorbidities, greater symptom severity, and respond less favorably to treatments than non-maltreated individuals with the same primary DSM-5 diagnosis. Furthermore, maltreated individuals have alterations in stress-susceptible brain regions, hypothalamic-pituitary-adrenal response, and inflammatory marker levels not discernible in their non-maltreated counterparts. Hence, maltreated and non-maltreated individuals with the same primary DSM-5 diagnoses appear to be clinically and neurobiologically distinct. The failure to embody this distinction in DSM-5 has interfered with our ability to discover novel treatments, to recommend currently available treatments most likely to be efficacious, and has been a largely unrecognized confound that has thwarted our ability to identify the biological basis for major psychiatric disorders. Incorporating this distinction into DSM will help transform this sign and symptom-based classification system to a more etiologically informed nosology. We discuss several diagnostic alternatives and recommend the inclusion of a Developmental Trauma Disorder diagnosis for severely dysregulated individuals, of all ages, with numerous comorbidities, who experienced interpersonal victimization and disruptions in attachment, such as emotional maltreatment or neglect. For less severely affected maltreated individuals, we suggest using conventional diagnostic categories, such as major depression, but with an essential modifier indicating a history of childhood maltreatment, or early life stress, to delineate the ecophenotypic variant. Implementing this strategy should improve our ability to effectively diagnose and treat individuals with psychiatric disorders and to accelerate discovery.

Clinical and Biological Factors Are Associated with Treatment-Resistant Depression

Background: Treatment-resistant depression (TRD) is a debilitating condition associated with unmet clinical needs. Few studies have explored clinical characteristics and serum biomarkers associated with TRD. Aims: We investigated whether there were differences in clinical and biochemical variables between patients affected by TRD than those without. Methods: We recruited 343 patients (165 males and 178 females) consecutively hospitalized for MDD to the inpatient clinics affiliated to the Fondazione IRCCS Policlinico, Milan, Italy (n = 234), and ASST Monza, Italy (n = 109). Data were obtained through a screening of the clinical charts and blood analyses conducted during the hospitalization. Results: TRD versus non-TRD patients resulted to be older (p = 0.001), to have a longer duration of illness (p < 0.001), to be more currently treated with a psychiatric poly-therapy (p < 0.001), to have currently more severe depressive symptoms as showed by the Hamilton Depression Rating Scale (HAM-D) scores (p = 0.016), to have lower bilirubin plasma levels (p < 0.001). In addition, more lifetime suicide attempts (p = 0.035), more antidepressant treatments before the current episode (p < 0.001), and a lower neutrophil to lymphocyte ratio at borderline statistically significant level (p = 0.060) were all associated with the TRD group. Conclusion: We identified candidate biomarkers associated with TRD such as bilirubin plasma levels and NLR, to be confirmed by further studies. Moreover, TRD seems to be associated with unfavorable clinical factors such as a predisposition to suicidal behaviors. Future research should replicate these results to provide robust data in support of the identification of new targets of treatment and implementation of prevention strategies for TRD.

Glutamatergic System in Depression and Its Role in Neuromodulatory Techniques Optimization

Depressive disorders are among the most common psychiatric conditions and contribute to significant morbidity. Even though the use of antidepressants revolutionized the management of depression and had a tremendous positive impact on the patient's outcome, a significant proportion of patients with major depressive disorder (MDD) show no or partial or response even with adequate treatment. Given the limitations of the prevailing monoamine hypothesis-based pharmacotherapy, glutamate and glutamatergic related pathways may offer an alternative and a complementary option for designing novel intervention strategies. Over the past few decades, there has been a growing interest in understanding the neurobiological underpinnings of glutamatergic dysfunctions in the pathogenesis of depressive disorders and the development of new pharmacological and non-pharmacological treatment options. There is a growing body of evidence for the efficacy of neuromodulation techniques, including transcranial magnetic stimulation, transcutaneous direct current stimulation, transcranial alternating current stimulation, and photo-biomodulation on improving connectivity and neuroplasticity associated with depression. This review attempts to revisit the role of glutamatergic neurotransmission in the etiopathogenesis of depressive disorders and review the current neuroimaging, neurophysiological and clinical evidence of these neuromodulation techniques in the pathophysiology and treatment of depression.

Inflammatory cytokines, cognition, and response to antidepressant treatment in patients with major depressive disorder

BACKGROUND

Inflammation and cognition are related to major depressive disorder (MDD), but the role in treatment response remains unclear. In this study, we investigated correlation between inflammatory cytokines and cognition in MDD patients treated with antidepressant medication.

METHODS

The participants were 149 MDD patients. Cytokines before therapy, cognitive assessments and severity of depression before and after therapy were tested. Logistic regression was used to explore underlying risks treatment response.

RESULTS

There were significant differences in smoking, alcohol drinking, and Stroop Color Test(SCT), Stroop Color-Word Test (SCWT), and Continuous Performance Test(CPT) scores between response group (RG) and non-response group (NRG) at baseline. Performance of patients in RG improved more in Brief Assessment of Cognition in Schizophrenia (BACS), Color Trial Test-I (CTT-I), SCT and SCWT after treatment. Levels of baseline IL-18 were associated with baseline learning and memory, and executive function. Treatment response was associated with drinking, performance of CPT and SCT.

CONCLUSION

MDD patients with different treatment responses have different cognitive defects, especially in speed of processing and executive function. Expression of cytokines is associated with cognition and may influence treatment response. Better speed of processing and executive function, and poorer attention at baseline may respond better to antidepressant treatment.

Change in Interpersonal and Metacognitive Skills During Treatment With Cognitive Behavioral Analysis System of Psychotherapy and Metacognitive Therapy: Results From an Observational Study

Background: Interpersonal skills deficits and dysfunctional metacognitive beliefs have been implicated in the etiology and maintenance of depression. This study aimed to investigate the association between changes in these skills deficits and change in depressive symptoms over the course of treatment with Cognitive Behavioral Analysis System of Psychotherapy (CBASP) and Metacognitive Therapy (MCT). Methods: In this prospective, parallel group observational study, data was collected at baseline and after 8 weeks of an intensive day clinic psychotherapy program. Based on a shared decision between patients and clinicians, patients received either CBASP or MCT. Ninety patients were included in the analyses (CBASP: age M = 38.7, 40.5% female, MCT: age M = 44.7, 43.3% female). Interpersonal deficits were assessed with the short-form of the Luebeck Questionnaire for Recording Preoperational Thinking (LQPT-SF) and the Impact Message Inventory (IMI-R). Metacognitive beliefs were assessed with the Metacognition Questionnaire-30 (MCQ-30). The Quick Inventory of Depressive Symptomatology (QIDS-SR16) was utilized to assess depressive symptoms. A regression analysis was conducted to assess variables associated with outcome. ANCOVAs were utilized to investigate whether improvement in skills deficits is dependent on type of treatment received. Results: Improvements in preoperational thinking and increases in friendly-dominant behavior were associated with change in depressive symptoms. There was no association between reductions in dysfunctional metacognitive beliefs and a decrease in depressive symptoms. While both treatment groups showed significant improvements in interpersonal and metacognitive skills, there was no significant between-group difference in the change scores for either of these skills. Conclusion: Our findings suggest that changes in interpersonal skills seem to be of particular relevance in the treatment of depression. These results have to be replicated in a randomized-controlled design before firm conclusions can be drawn.

Healthcare Resource Consumption and Related Costs of Patients Estimated with Treatment-Resistant Depression in Italy

Purpose

To analyse the healthcare resource consumption and related costs for the Italian National Health System of patients estimated to be affected by treatment-resistant depression (TRD) in Italy.

Patients and Methods

This was an observational retrospective study based on administrative databases, including those related to residential/semiresidential structures, of Veneto Region and the Local Health Unit of Bergamo in Italy (for a total of around 6 million health-assisted subjects). Between July 2011 and December 2017, all adult patients with a third antidepressant (AD) after ≥2 AD (each one with at least ≥4 weeks duration, ≥1 prescription at maximum dosage reported in datasheets, a grace period ≤30 days when switching AD and treatment maintained ≥9 months) were included. Overall and psychiatry-related healthcare resources consumption and related costs were estimated on a 12-months based analysis. Data were re-proportioned to the Italian population.

Results

We have previously estimated a total of 101,455 patients with TRD in Italy (130,049 considering the mean maximum dosage of AD). Of them, 44.2% had at least a psychiatric hospitalization/visit or accessed a residential/semiresidential structure, and 31% added another AD or a mood stabilizer/antipsychotic drug. Patients with at least one psychiatry-related hospitalization increased over the number of antidepressant lines from 12.0% during first line up to 24.5% during fourth line. Direct healthcare costs increased from €4,405 for first line to €9,251 from fifth line onwards. Psychiatry-related costs went from €1,817 (first line) to €4,606 (fifth line onwards) and were mainly driven by residential/semiresidential structures and hospitalizations.

Conclusion

An upward trend with number of AD lines was observed for all healthcare resource utilization and consequently for all direct costs, thus indicating an increasing burden for patients as they move forward AD lines.

Genetic and clinical characteristics of treatment-resistant depression using primary care records in two UK cohorts

Treatment-resistant depression (TRD) is a major contributor to the disability caused by major depressive disorder (MDD). Primary care electronic health records provide an easily accessible approach to investigate TRD clinical and genetic characteristics. MDD defined from primary care records in UK Biobank (UKB) and EXCEED studies was compared with other measures of depression and tested for association with MDD polygenic risk score (PRS). Using prescribing records, TRD was defined from at least two switches between antidepressant drugs, each prescribed for at least 6 weeks. Clinical-demographic characteristics, SNP-based heritability (h²_SNP) and genetic overlap with psychiatric and non-psychiatric traits were compared in TRD and non-TRD MDD cases. In 230,096 and 8926 UKB and EXCEED participants with primary care data, respectively, the prevalence of MDD was 8.7% and 14.2%, of which 13.2% and 13.5% was TRD, respectively. In both cohorts, MDD defined from primary care records was strongly associated with MDD PRS, and in UKB it showed overlap of 71-88% with other MDD definitions. In UKB, TRD vs healthy controls and non-TRD vs healthy controls h²_SNP was comparable (0.25 [SE = 0.04] and 0.19 [SE = 0.02], respectively). TRD vs non-TRD was positively associated with the PRS of attention deficit hyperactivity disorder, with lower socio-economic status, obesity, higher neuroticism and other unfavourable clinical characteristics. This study demonstrated that MDD and TRD can be reliably defined using primary care records and provides the first large scale population assessment of the genetic, clinical and demographic characteristics of TRD.

Does continuous positive airways pressure treatment improve clinical depression in obstructive sleep apnea? A randomized wait-list controlled study

BACKGROUND

Obstructive sleep apnea (OSA) is a highly prevalent sleep disorder that is associated with a range of adverse daytime sequelae, including significantly higher rates of clinical depression than is seen in the general community. Improvements in depressive symptoms occur after treatment of the primary sleep disorder, suggesting that comorbid depression might be an intrinsic feature of OSA. However, there are limited data on whether treatment for OSA in patients diagnosed with clinical depression improves mood symptoms meaningfully enough to lead to the remission of the psychiatric diagnosis.

METHODS

N = 121 untreated OSA patients were randomized to either continuous positive airway pressure (CPAP) treatment or waitlist control, and depressive symptoms, sleepiness and clinical depression (using a structured clinical interview) were assessed at baseline and 4 months. Linear and logistic regression analyses were conducted, controlling for baseline scores, stratification factors and antidepressant use.

RESULTS

Depressive symptoms (odds ratio [OR] = -4.19; 95% confidence interval [CI] = -7.25, -1.13; p = .008) and sleepiness (OR = -4.71; 95% CI = -6.26, -3.17; p < .001) were significantly lower at 4 months in the CPAP group compared to waitlist. At 4 months, there was a significant reduction in the proportion of participants in the CPAP group meeting criteria for clinical depression, compared to the waitlist controls (OR = 0.06, 95% CI = 0.01, 0.37; p = .002).

CONCLUSION

Treatment of OSA may be a novel approach for the management and treatment of clinical depression in those with comorbid sleep disordered breathing. Larger trials of individuals with clinical depression and comorbid OSA are needed.

Using a machine learning approach to investigate factors associated with treatment-resistant depression among adults with chronic non-cancer pain conditions and major depressive disorder

OBJECTIVE

Presence of chronic non-cancer pain conditions (CNPC) among adults with major depressive disorder (MDD) may reduce benefits of antidepressant therapy, thereby increasing the possibility of treatment resistance. This study sought to investigate factors associated with treatment-resistant depression (TRD) among adults with MDD and CNPC using machine learning approaches.

METHODS

This retrospective cohort study was conducted using a US claims database which included adults with newly diagnosed MDD and CNPC (January 2007-June 2017). TRD was identified using a clinical staging algorithm for claims data. Random forest (RF), a machine learning method, and logistic regression was used to identify factors associated with TRD. Initial model development included 42 known and/or probable factors that may be associated with TRD. The final refined model included 20 factors.

RESULTS

Included in the sample were 23,645 patients (73% female mean age: 55 years; 78% with ≥2 CNPC, and 91% with joint pain/arthritis). Overall, 11.4% adults (N = 2684) met selected criteria for TRD. The five leading factors associated with TRD were the following: mental health specialist visits, polypharmacy (≥5 medications), psychotherapy use, anxiety, and age. Cross-validated logistic regression model indicated that those with TRD were younger, more likely to have anxiety, mental health specialist visits, polypharmacy, and psychotherapy use with adjusted odds ratios (AORs) ranging from 1.93 to 1.27 (all ps < .001).

CONCLUSION

Machine learning identified several factors that warrant further investigation and may serve as potential targets for clinical intervention to improve treatment outcomes in patients with TRD and CNPC.

Treatment-resistant major depressive disorder: Canadian expert consensus on definition and assessment

BACKGROUND

Treatment-resistant depression (TRD) is a debilitating chronic mental illness that confers increased morbidity and mortality, decreases the quality of life, impairs occupational, social, and offspring development, and translates into increased costs on the healthcare system. The goal of this study is to reach an agreement on the concept, definition, staging model, and assessment of TRD.

METHODS

This study involved a review of the literature and a modified Delphi process for consensus agreement. The Appraisal of Guidelines for Research & Evaluation II guidelines were followed for the literature appraisal. Literature was assessed for quality and strength of evidence using the grading, assessment, development, and evaluations system. Canadian national experts in depression were invited for the modified Delphi process based on their prior clinical and research expertize. Survey items were considered to have reached a consensus if 80% or more of the experts supported the statement.

RESULTS

Fourteen Canadian experts were recruited for three rounds of surveys to reach a consensus on a total of 27 items. Experts agreed that a dimensional definition for treatment resistance was a useful concept to describe the heterogeneity of this illness. The use of staging models and clinical scales was recommended in evaluating depression. Risk factors and comorbidities were identified as potential predictors for treatment resistance.

CONCLUSIONS

TRD is a meaningful concept both for clinical practice and research. An operational definition for TRD will allow for opportunities to improve the validity of predictors and therapeutic options for these patients.

Higher Negative Self-Reference Level in Patients With Personality Disorders and Suicide Attempt(s) History During Biological Treatment for Major Depressive Disorder: Clinical Implications

Objective: The aim of the study was to identify clinical variables associated with changes in specific domains of self-reported depression during treatment by antidepressant and/or repetitive Transcranial Magnetic Stimulation (rTMS) in patients with Major Depressive Disorder (MDD).

Methods: Data from a trial involving 170 patients with MDD receiving either venlafaxine, rTMS or both were re-analyzed. Depressive symptoms were assessed each week during the 2 to 6 weeks of treatment with the 13-item Beck Depression Inventory (BDI₁₃). Associations between depression changes on BDI₁₃ domains (Negative Self-Reference, Sad Mood, and Performance Impairment), treatment arm, time, and clinical variables were tested in a mixed linear model.

Results: A significant decrease of self-reported depressive symptoms was observed over time. The main characteristics associated with persistent higher depressive symptomatology on Negative Self-Reference domain of the BDI₁₃ were personality disorders (+2.1 points), a past history of suicide attempt(s) (+1.7 points), age under 65 years old (+1.5 points), and female sex (+1.1 points).

Conclusions: Early cognitive intervention targeting specifically negative self-referencing process could be considered during pharmacological or rTMS treatment for patients with personality disorders and past history of suicide attempt(s).

A pilot investigation of accelerated deep transcranial magnetic stimulation protocols in treatment-resistant depression

Accelerated repetitive transcranial magnetic stimulation (rTMS) protocols are being increasingly studied because of their potential to provide quicker and enhanced treatment efficacy. However, there is a lack of accelerated deep TMS with H1-coil (adTMS) treatment research. This randomized pilot study investigated the efficacy and safety of adTMS protocols. Twenty-eight TRD patients received 20-min sessions twice daily for 10 or 15 days. Primary outcomes were changes in Hamilton Depression Rating Scale (HDRS) scores and discontinuation because of adverse events (AE). Secondary outcomes were response, remission, daily changes in Beck Depression Inventory-II (BDI-II) scores, and AE incidence. HDRS scores decreased by 13 (95% CI 11-17; 59%, 95% CI 45-73%) and 13 (95% CI 11-14; 62%, 95% CI 54-69%) points in the 10- and 15-day protocols, respectively. The adjusted difference between the two protocols was not significant or clinically relevant. Remission was achieved by 38% and 42% after 10-day and 15-day protocols, respectively. The intervention was discontinued because of AEs in 3/33 (9%) patients. The BDI-II decreases were significant and clinically relevant during the first 8 days. Twice-daily adTMS for 10 days seems to be safe and effective, with rapid clinical benefits during the first week of treatment. These promising results warrant further investigation in larger randomized clinical trials comparing adTMS with the standard dTMS protocol.

Multiple lifestyle factors and depressed mood: a cross-sectional and longitudinal analysis of the UK Biobank (N = 84,860)

BACKGROUND

There is now evolving data exploring the relationship between depression and various individual lifestyle factors such as diet, physical activity, sleep, alcohol intake, and tobacco smoking. While this data is compelling, there is a paucity of longitudinal research examining how multiple lifestyle factors relate to depressed mood, and how these relations may differ in individuals with major depressive disorder (MDD) and those without a depressive disorder, as 'healthy controls' (HC).

METHODS

To this end, we assessed the relationships between 6 key lifestyle factors (measured via self-report) and depressed mood (measured via a relevant item from the Patient Health Questionnaire) in individuals with a history of or current MDD and healthy controls (HCs). Cross-sectional analyses were performed in the UK Biobank baseline sample, and longitudinal analyses were conducted in those who completed the Mental Health Follow-up.

RESULTS

Cross-sectional analysis of 84,860 participants showed that in both MDD and HCs, physical activity, healthy diet, and optimal sleep duration were associated with less frequency of depressed mood (all p < 0.001; ORs 0.62 to 0.94), whereas screen time and also tobacco smoking were associated with higher frequency of depressed mood (both p < 0.0001; ORs 1.09 to 1.36). In the longitudinal analysis, the lifestyle factors which were protective of depressed mood in both MDD and HCs were optimal sleep duration (MDD OR = 1.10; p < 0.001, HC OR = 1.08; p < 0.001) and lower screen time (MDD OR = 0.71; p < 0.001, HC OR = 0.80; p < 0.001). There was also a significant interaction between healthy diet and MDD status (p = 0.024), while a better-quality diet was indicated to be protective of depressed mood in HCs (OR = 0.92; p = 0.045) but was not associated with depressed mood in the MDD sample. In a cross-sectional (OR = 0.91; p < 0.0001) analysis, higher frequency of alcohol consumption was surprisingly associated with reduced frequency of depressed mood in MDD, but not in HCs.

CONCLUSIONS

Our data suggest that several lifestyle factors are associated with depressed mood, and in particular, it calls into consideration habits involving increased screen time and a poor sleep and dietary pattern as being partly implicated in the germination or exacerbation of depressed mood.

A retrospective analysis to estimate the healthcare resource utilization and cost associated with treatment-resistant depression in commercially insured US patients

OBJECTIVE

The economic burden of commercially insured patients in the United States with treatment-resistant depression and patients with non-treatment-resistant major depressive disorder was compared using data from the Optum Clinformatics™ claims database.

METHODS

Patients 18-63 years on antidepressant treatment between 1/1/13 and 9/30/13, who had no treatment claims for depression 6 months before the index date (first antidepressant dispensing), and who had a major depressive disorder or depression diagnosis within 30 days of the index date, were included. Treatment-resistant depression was defined as receiving 3 antidepressant regimens during 1 major depressive disorder episode. Patients with treatment-resistant depression were matched with patients with non-treatment-resistant major depressive disorder at a 1:4 ratio using propensity score matching. The study consisted of 1-year baseline (pre-index) and 2-year follow-up (post index) periods. Cost outcomes were compared using a generalized linear model.

RESULTS

2,370 treatment-resistant depression and 9,289 non-treatment-resistant major depressive disorder patients were included. In year 1 of the follow-up period, compared with non-treatment-resistant major depressive disorder, patients with treatment-resistant depression had: more emergency department visits (odds ratio = 1.39, 95% confidence interval = 1.24-1.56); more inpatient hospitalizations (odds ratio = 1.73, 95% confidence interval = 1.46-2.05); longer hospital stays (mean difference vs non-treatment-resistant major depressive disorder = 2.86, 95% confidence interval = 0.86-4.86 days); and more total healthcare costs (mean difference vs non-treatment-resistant major depressive disorder = US$3,846, 95% confidence interval = $2,855-$4,928). These patterns remained consistent in year 2 of the follow-up period.

CONCLUSION

Treatment-resistant depression was associated with higher healthcare resource utilization and costs versus non-treatment-resistant major depressive disorder in this commercially insured cohort of patients in the United States.

A Tellurium-Based Small Immunomodulatory Molecule Ameliorates Depression-Like Behavior in Two Distinct Rat Models

Major depressive disorder (MDD) is a leading cause of morbidity, and the fourth leading cause of disease burden worldwide. While MDD is a treatable condition for many individuals, others suffer from treatment-resistant depression (TRD). Here, we suggest the immunomodulatory compound AS101 as novel therapeutic alternative. We previously showed in animal models that AS101 reduces anxiety-like behavior and elevates levels of the brain-derived neurotrophic factor (BDNF), a protein that has a key role in the pathophysiology of depression. To explore the potential antidepressant properties of AS101, we used the extensively characterized chronic mild stress (CMS) model, and the depressive rat line (DRL Finally, in Exp. 3 to attain insight into the mechanism we knocked down BDNF in the hippocampus, and demonstrated that the beneficial effect of AS101 was abrogated. Together with the previously established safety profile of AS101 in humans, these results may represent the first step towards the development of a novel treatment option for MDD and TRD.

Alterations of mental defeat and cognitive flexibility during cognitive behavioral therapy in patients with major depressive disorder: a single-arm pilot study

Objective

Mental defeat affects the occurrence and chronicity of depression and cognitive flexibility. This study aimed to examine changes in mental defeat and cognitive flexibility scores after cognitive behavioral therapy including IR. In the intervention group, patients with depression (n = 18, mean age = 37.89 years) received 15 cognitive behavioral therapy sessions. Patients completed the Beck Depression Inventory-II; Mental Defeat Scale; Cognitive Flexibility Scale; EuroQol five dimensions questionnaire; Patient Health Questionnaire-9 and seven-item Generalized Anxiety Disorder Scale before the intervention, after six sessions, and post-intervention. The healthy control group (n = 33, mean age = 37.91) completed all scales once and did not receive treatment.

Results

Post-cognitive behavioral therapy, a significant decrease was observed in Beck Depression Inventory-II, Mental Defeat Scale, Cognitive Flexibility Scale, and Patient Health Questionnaire-9 scores. Although mental defeat and cognitive flexibility did not reach the level of the healthy control group, they demonstrated improvement. Therefore, when treating depression, mental defeat and cognitive flexibility should be measured in addition to depressive symptoms.

Trial registration This study was registered retrospectively in the national UMIN Clinical Trials Registry on July 25, 2016 (registration ID: UMIN000023320)

Prevalence of obstructive sleep apnea in suicidal patients with major depressive disorder

In this paper, we report the rate of previously undiagnosed obstructive sleep apnea (OSA) in a randomized clinical trial (RCT) of suicidal patients with major depressive disorder (MDD). One hundred and twenty-five suicidal adults with MDD were recruited into a RCT. None were suspected to have OSA. Fourteen percent met diagnostic criteria for OSA. The Apnea Hypopnea Index (AHI) was predicted by increasing age, male sex, and higher Body Mass Index. However, neither the degree of daytime sleepiness nor the degree of insomnia predicted AHI severity. A high degree of suspicion is warranted for OSA in suicidal patients with MDD, and for patients with treatment-resistant depression. ClinicalTrials.gov identifier: NCT01689909.

All-cause mortality in patients with treatment-resistant depression: a cohort study in the US population

BACKGROUND

Treatment-resistant depression (TRD) may represent a substantial proportion of major depressive disorder (MDD); however, the risk of mortality in TRD is still incompletely assessed.

METHODS

Data were obtained from Optum Clinformatics™ Extended, a US claims database. Date of the first antidepressant (AD) dispensing was designated as the index date for study entry and 6 months prior to that was considered the baseline period. Patients with MDD aged ≥ 18 years, index date between January 1, 2008 and September 30, 2015, no AD claims during baseline, and continuous enrollment in the database during baseline were included. Patients who started a third AD regimen after two regimens of appropriate duration were included in the TRD cohort. All-cause mortality was compared between patients with TRD and non-TRD MDD using a proportional hazards model and Kaplan-Meier estimate with TRD status being treated as a time-varying covariate. The model was adjusted for study year, age, gender, depression diagnosis, substance use disorder, psychiatric comorbidities, and Charlson comorbidity index.

RESULTS

Out of 355,942 patients with MDD, 34,176 (9.6%) met the criterion for TRD. TRD was associated with a significantly higher mortality compared with non-TRD MDD (adjusted HR: 1.29; 95% CI 1.22-1.38; p < 0.0001). Survival time was significantly shorter in the TRD cohort compared with the non-TRD MDD cohort (p < 0.0001).

CONCLUSIONS

Patients with TRD had a higher all-cause mortality compared with non-TRD MDD patients.

Adjunctive S-adenosylmethionine (SAMe) in treating non-remittent major depressive disorder: An 8-week double-blind, randomized, controlled trial<sup/>

There has been increasing interest in nutraceutical augmentation strategies to boost the efficacy of antidepressants. This study assessed whether S-adenosylmethionine (SAMe), a methyl donor that occurs naturally in the body, may be of such benefit. We conducted an 8-week, double-blind RCT in which 107 treatment non-remittent outpatients with DSM-5 diagnosed Major Depressive Disorder (MDD) were randomized to either SAMe or placebo adjunctively to antidepressants. One-carbon cycle nutrients, pertinent single nucleotide polymorphisms (SNPs), and BDNF were also analysed as potential moderators of response. A linear mixed-effects model revealed a significant overall reduction in Montgomery-Asberg Depression Rating Scale (MADRS) score across time, however there was no significant between-group difference observed (p = 0.51). Response rates at Week 8 were 54.3% in the SAMe group and 50.0% in the placebo group, with remission rates 43.5% for SAMe and 38.3% for placebo (all results NS). No effect of SAMe was found on any secondary outcome. Differential response to SAMe was not modified by a range of key genotypes (e.g. COMT), nor reflected in a change of homocysteine, red cell folate, or BDNF. Use of SAMe elicited no significant adverse effects beyond placebo, however it was implicated in one case of serotonin syndrome-like symptoms. This study concludes that 800 mg/day of SAMe is not an effective adjunctive treatment in MDD, and no obvious biomarker reflected any differential response to treatment. Due to such a distinctly high placebo-response (despite rigorous screening), future studies should employ a placebo run-in period and other strategies to minimize placebo response.

Vagus Nerve Stimulation (VNS) and Other Augmentation Strategies for Therapy-Resistant Depression (TRD): Review of the Evidence and Clinical Advice for Use

In addition to electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS), vagus nerve stimulation (VNS) is one of the approved neurostimulation tools for treatment of major depression. VNS is particularly used in therapy-resistant depression (TRD) and exhibits antidepressive and augmentative effects. In long-term treatment, up to two-thirds of patients respond. This mini-review provides a comprehensive overview of augmentation pharmacotherapy and neurostimulation-based treatment strategies, with a special focus on VNS in TRD, and provides practical clinical advice for how to select TRD patients for add-on neurostimulation treatment strategies.