Pharmacologic treatment of dimensional anxious depression: a review

Does depression with current suicidal ideation lead to treatment-resistant depression? Two large naturalistic cohorts of outpatients with depression and current suicidal ideation

As treatment-resistant depression (TRD) is linked to suicidal behaviors and suicidal risk is a predictor of TRD, depression with current suicidal ideation (SI) may lead to TRD. Early identification of TRD risk factors in patients with depression and current SI is crucial. The aims of our study were: i) to identify risk factors for depression non-remission and TRD in patients with depression and current SI; ii) to assess if SI at baseline mediated the relationship between depression severity at baseline and depression remission at week 6. We analyzed data from two large, prospective, naturalistic French cohorts of adult outpatients with depression (DSM-IV criteria) followed for 6 weeks after starting or changing antidepressants (LUEUR and GENESE). Sociodemographic and clinical characteristics, along with early symptom improvement, were compared between patients with and without current SI using logistic regression models (univariate and multivariate). Patients with antidepressant change or initiation were analyzed separately. Those without depression remission at week 6 after an antidepressant change were considered TRD cases. In patients with antidepressant change, the major predictor of non-remission was poorer early improvement (at week 2) of anxiety. For patients with treatment initiation, SI at baseline mediated the relation between depression severity at baseline and depression remission. Depression severity at baseline alone did not explain depression remission. Clinicians should systematically target with specific pharmacological and non-pharmacological treatments anxiety and SI and assess their changes in the short term to increase the chance of depression remission in depressed patients with current SI.

The Effects of Variation in the GABAA Receptor Gene on Anxious Depression are Mediated by the Functional Connectivity Between the Amygdala and Middle Frontal Gyrus

Background

γ-aminobutyric acid (GABA) and its main receptor, the GABAA receptor, are implicated in major depressive disorder (MDD). Anxious depression (AD) is deemed to be a primary subtype of MDD. The amygdala and the dorsolateral prefrontal cortex (DLPFC) are key brain regions involved in emotional regulation. These regions contain the most GABAA receptors. Although the GABAergic deficit hypothesis of MDD is generally accepted, few studies have demonstrated how GABAA receptor gene polymorphisms affect the functions of specific brain regions, in particular, the amygdala and the DLPFC.

Methods

The sample comprised 83 patients with AD, 70 patients with non-anxious depression (NAD), and 62 healthy controls (HC). All participants underwent genotyping for polymorphisms of GABAA receptor subunit genes, followed by a resting-state fMRI scan. The HAMD-17 was used to evaluate the severity of MDD. ANOVA was performed to obtain the difference in the imaging data, GABAA receptor multi-locus genetic profile scores (MGPS), and HAMD-17 scores among three groups, then the significant differences between AD and NAD groups were identified. Mediating effect analysis was used to explore the role of functional connectivity (FC) between the amygdala and DLPFC in the association between the GABAA receptor gene MGPS and AD clinical features.

Results

Compared with the NAD group, the AD group had a higher GABAA receptor MGPS. AD patients exhibited a negative correlation between the MGPS and FC of the right centromedial (CM) subregion, and the right middle frontal gyrus (MFG). A negative correlation was also observed between the MGPS and anxiety/somatic symptoms. More importantly, the right CM and right MFG connectivity mediated the association between the GABAA receptor MGPS and anxiety/somatic symptoms in patients with AD.

Conclusion

The decreased FC between the right MFG and right CM subregion mediates the association between GABAA receptor MGPS and AD.

The Clinical Characteristics and Manifestation of Anxious Depression Among Patients With Major Depressive Disorders-Results From a Taiwan Multicenter Study

OBJECTIVE

Anxious depression is a prevalent characteristic observed in Asian psychiatric patients diagnosed with major depressive disorder (MDD). This study aims to investigate the prevalence and clinical presentation of anxious depression in Taiwanese individuals diagnosed with MDD.

METHODS

We recruited psychiatric outpatients aged over 18 who had been diagnosed with MDD through clinical interviews. This recruitment took place at five hospitals located in northern Taiwan. We gathered baseline clinical and demographic information from the participants. Anxious depression was identified using a threshold of an anxiety/somatization factor score ≥7 on the 21-item Hamilton Rating Scale for Depression (HAM-D).

RESULTS

In our study of 399 patients (84.21% female), 64.16% met the criteria for anxious depression. They tended to be older, married, less educated, with more children, and an older age of onset. Anxious depression patients had higher HAM-D and Clinical Global Impression-Severity scale score, more panic disorder (without agoraphobia), and exhibited symptoms like agitation, irritability, concentration difficulties, psychological and somatic anxiety, somatic complaints, hypochondriasis, weight loss, and increased insight. Surprisingly, their suicide rates did not significantly differ from non-anxious depression patients. This highlights the importance of recognizing and addressing these unique characteristics.

CONCLUSION

Our study findings unveiled that the prevalence of anxious depression among Taiwanese outpatients diagnosed with MDD was lower compared to inpatients but substantially higher than the reported rates in European countries and the United States. Furthermore, patients with anxious depression exhibited a greater occurrence of somatic symptoms.

The unique face of anxious depression: Increased sustained threat circuitry response during fear acquisition

Background

Sensitivity to threat with dysregulation of fear learning is thought to contribute to the development of psychiatric disorders, including anxiety disorders (AD) and major depressive disorder (MDD). However, fewer studies have examined fear learning in MDD than in AD. Nearly half of individuals with MDD have an AD and the comorbid diagnosis has worse outcomes. The current study used propensity matching to examine the hypothesis that AD+MDD shows greater neural correlates of fear learning than MDD, suggesting that the co-occurrence of AD+MDD is exemplified by exaggerated defense related processes.

Methods

195 individuals with MDD (N = 65) or AD+MDD (N=130) were recruited from the community and completed multi-level assessments, including a Pavlovian fear learning task during functional imaging.

Results

MDD and AD+MDD showed significantly different patterns of activation for [CSplus-CSminus] in the medial amygdala (ηp2=0.009), anterior insula (ηp2=0.01), dorsolateral prefrontal cortex (ηp2=0.002), dorsal anterior cingulate cortex (ηp2=0.01), mid-cingulate cortex (ηp2=0.01) and posterior cingulate cortex (ηp2=0.02). These differences were driven by greater activation to the CS+ in late conditioning phases in ADD+MDD relative to MDD.

Conclusions

AD+MDD showed a pattern of increased sustained activation in regions identified with fear learning. Effects were consistently driven by the threat condition, further suggesting fear signaling as the emergent target process. Differences emerged in regions associated with salience processing, attentional orienting/conflict, and self-relevant processing.These findings help to elucidate the fear signaling mechanisms involved in the pathophysiology of comorbid anxiety and depression, thereby highlighting promising treatment targets for this prevalent treatment group.

Dexmedetomidine in the Treatment of Depression: An Up-to-date Narrative Review

Depressive disorders (DD) are common, and their prevalence is expected to rise over the next decade. Depressive disorders are linked to significant morbidity and mortality. The clinical conundrum of depressive disorders lies in the heterogeneity of their phenomenology and etiology. Further, the currently available antidepressants have several limitations, including a delayed onset of action, limited efficacy, and an unfavorable side effect profile. In this review, Dexmedetomidine (DEX), a highly selective and potent α2-adrenergic receptor (α2-AR) agonist, is proposed as a potentially novel antidepressant with multiple mechanisms of action targeting various depression pathophysiological processes. These mechanisms include modulation of the noradrenergic system, regulation of neuroinflammation and oxidative stress, influence on the Brain-Derived Neurotrophic Factor (BDNF) levels, and modulation of neurotransmitter systems, such as glutamate. The review begins with an introduction before moving on to a discussion of DEX's pharmacological features. The pathophysiological and phenomenological targets of DD are also explored, along with the review of the existing preclinical and clinical evidence for DEX's putative anti-depressant effects. Finally, the review ends by presenting the pertinent conclusions and future directions.

The unique face of comorbid anxiety and depression: increased interoceptive fearfulness and reactivity

Anxiety and depression commonly co-occur, yet the underlying brain and behavioral processes are poorly understood. Here we examined the hypothesis that individuals with comorbid anxiety and depression would show increased fearful reactivity to an aversive interoceptive perturbation relative to depressed-only individuals. One-hundred and eighty anxious and/or depressed participants from the Tulsa 1000 study completed multi-level behavioral or functional magnetic resonance imaging assessments of interoception and nociception including breath-hold and cold-pressor challenges, and heartbeat perception and interoceptive attention tasks. One-hundred and four individuals with comorbid depression and anxiety disorders (Dep+Anx) were propensity matched with 52 individuals with depression-only (Dep). Data were analyzed using mixed-effects linear regression. The Dep+Anx group showed significantly greater self-reported fear of suffocation during breath holding (Wilcoxon r = 0.23) and reduced cold pain tolerance (R ² = 0.027) signified by hand removal during immersion. However, these groups did not differ with respect to neutrally-valenced behavioral indices of heartbeat perception or neural indices of interoceptive attention. Individuals with comorbid depression and anxiety, vs. those with only depression, show increased respiratory fearfulness and nociceptive reactivity during perturbations of these signals, whilst showing similar interoceptive awareness in the absence of perturbation. Our findings suggest that individuals with comorbid anxiety and depression process aversive interoceptive and nociceptive signals differently than those with depression alone, providing support for a process model of increased threat sensitivity and hyperarousal in anxious depression.

Antidepressant side effects and their impact on treatment outcome in people with major depressive disorder: an iSPOT-D report

Side effects to antidepressant medications are common and can impact the prognosis of successful treatment outcome in people with major depressive disorder (MDD). However, few studies have investigated the severity of side effects over the course of treatment and their association with treatment outcome. Here we assessed the severity of side effects and the impact of treatment type and anxiety symptoms over the course of treatment, as well as whether side effects were associated with treatment outcome. Participants were N = 1008 adults with a current diagnosis of single-episode or recurrent, nonpsychotic MDD. Participants were randomised to receive escitalopram, sertraline, or venlafaxine-extended release with equal probability and reassessed at 8 weeks regarding Hamilton Rating Scale Depression (HRSD₁₇) and Quick Inventory of Depressive Symptomatology (QIDS-SR₁₆) remission and response. Severity of side effects were assessed using the Frequency, Intensity, and Burden of Side Effects Rating (FIBSER) scale and assessed at day 4 and weeks 2, 4, 6, and 8. Frequency, intensity, and burden of side effects were greatest at week 2, then only frequency and intensity of side effects gradually decreased up to week 6. Treatment type and anxiety symptoms did not impact the severity of side effects. A greater burden-but not frequency or intensity-of side effects was associated with poorer treatment outcome and as early as 4 days post-treatment. Together, this work provides an informative mapping of the progression of side effects throughout the treatment course and their association with treatment outcome. Importantly, the burden of side effects that are present as early as 4 days post-treatment predicts poorer treatment outcome and should be monitored closely. iSPOT-D: Registry name: ClinicalTrials.gov. Registration number: NCT00693849.

Common and Specific Alterations of Amygdala Subregions in Major Depressive Disorder With and Without Anxiety: A Combined Structural and Resting-State Functional MRI Study

Anxious major depressive disorder is a common subtype of major depressive disorder; however, its unique neural mechanism is not well-understood currently. Using multimodal MRI data, this study examined common and specific alterations of amygdala subregions between patients with and without anxiety. No alterations were observed in the gray matter volume or intra-region functional integration in either patient group. Compared with the controls, both patient groups showed decreased functional connectivity between the left superficial amygdala and the left putamen, and between the right superficial amygdala and the bilateral anterior cingulate cortex and medial orbitofrontal cortex, while only patients with anxiety exhibited decreased activity in the bilateral laterobasal and superficial amygdala. Moreover, the decreased activity correlated negatively with the Hamilton depression scale scores in the patients with anxiety. These findings provided insights into the pathophysiologic processes of anxious major depressive disorder and may help to develop new and effective treatment programs.

Updated Review and Meta-Analysis of Probiotics for the Treatment of Clinical Depression: Adjunctive vs. Stand-Alone Treatment

Recent years have seen a rapid increase in the use of gut microbiota-targeting interventions, such as probiotics, for the treatment of psychiatric disorders. The objective of this update review was to evaluate all randomised controlled clinical trial evidence on the efficacy of probiotics for clinical depression. Cochrane guidelines for updated reviews were followed. By searching PubMed and Web of Science databases, we identified 546 new records since our previous review. A total of seven studies met selection criteria, capturing 404 people with depression. A random effects meta-analysis using treatment type (stand-alone vs. adjunctive) as subgroup was performed. The results demonstrated that probiotics are effective in reducing depressive symptoms when administered in addition to antidepressants (SMD = 0.83, 95%CI 0.49-1.17), however, they do not seem to offer significant benefits when used as stand-alone treatment (SMD = -0.02, 95%CI -0.34-0.30). Potential mechanisms of action may be via increases in brain-derived neurotrophic factor (BDNF) and decreases in C-reactive protein (CRP), although limited evidence is available at present. This review offers stronger evidence to support the clinical use of probiotics in depressed populations and provides an insight into the mode of administration more likely to yield antidepressant effects.

A Preliminary Randomized Controlled Trial of Different Treatment Regimens for Melancholic Depression

BACKGROUND

Fluoxetine, bupropion, cognitive behavioral therapy (CBT), and physical therapies (modified electroconvulsive treatment or repetitive transcranial magnetic stimulation) can be used to manage melancholic depression.

OBJECTIVE

To compare the efficacy and safety of various treatments in patients with melancholic depression.

METHODS

This was a preliminary multicenter randomized controlled trial that included patients with depression in their first or recurrent acute episode between September 2016 and June 2019, and randomized to fluoxetine, fluoxetine+CBT, fluoxetine+bupropion, and fluoxetine+bupropion+brain stimulation. The primary endpoint was the decrease in the 17-item Hamilton Depression Rating Scale (17-HDRS). The secondary endpoint included the scores from the Quick Inventory of Depressive Symptomatology (QIDS-SR), QOL-6, and safety. Adverse events (AEs) were monitored. The follow-ups were performed at the end of the 0th, 2nd, 4th, 6th, 8th, and 12th weeks of treatment.

RESULTS

Finally, 113 patients were included in the analyses: fluoxetine (n=37), fluoxetine+CBT (n=27), fluoxetine+bupropion (n=34), and fluoxetine+bupropion+brain stimulation (n=15). The 17-HDRS and QIDS-SR scores decreased in all four groups (all P<0.05). There were no differences in the 17-HDRS scores among the four groups at the end of treatment (P=0.779), except for fluoxetine alone showing a better response regarding self-consciousness than fluoxetine+bupropion. The QOL-6 scores increased in all four groups. The occurrence of AEs among the four groups showed no significant difference (P=0.053).

CONCLUSION

This preliminary trial suggests that all four interventions (fluoxetine, fluoxetine+CBT, fluoxetine+bupropion, and fluoxetine+bupropion+brain stimulation) achieved similar response and remission rates in patients with melancholic depression, but that fluoxetine had a better effect on self-consciousness than fluoxetine+bupropion. The safety profile was manageable.

Increased Hypocretin (Orexin) Plasma Level in Depression, Bipolar Disorder Patients

As hypocretin can markedly affect neurophysiological and behavioural processes in mood disorders. However, few studies have measured changes in hypocretin levels in patients with mood disorders. We estimated the hypocretin-1 plasma levels in mood disorder patients and controls (CON) using an enzyme-linked immunosorbent assay. Results: (i) The hypocretin-1 plasma level was significantly higher in major depressive disorder (MDD) patients [59.04 (35.78-80.12) pg/ml, P < 0.001] and bipolar disorder (BD) patients [65.50 (58.46-74.57) pg/ml, P < 0.001] patients than in CON [49.25 (28.51-80.40) pg/ml]. Moreover, the plasma hypocretin-1 levels in the BD group were significantly higher than those in the MDD group (P < 0.001). (ii). In the MDD group, patients with higher suicidal ideation had higher hypocretin-1 levels [62.09 (38.23-80.12) pg/ml] than those with lower suicidal ideation [59.63 (35.79-77.37) pg/ml), P = 0.032]. (iii). Plasma hypocretin-1 levels were increased in both female and male mood disorder patients compared to CON [male: MDD 60.51 (35.79-80.12) pg/ml; BD 65.40 (58.76-74.14) pg/ml; CON 45.63 (28.51-62.05) pg/ml; all P < 0.016; female: MDD 57.37 (34.59-80.40) pg/ml; BD 65.61 (58.46-74.57) pg/ml; CON 52.92 (38.23-78.89) pg/ml; all P < 0.015]. (iv). In CON, we found a significant negative correlation between plasma hypocretin-1 levels and age (rho = -0.251, P = 0.032), while this negative correlation was absent in the MDD and BD groups. Limitations may partly arise from the relatively small sample size and the medication history of patients participating in our research. We concluded that the clear changes found in plasma hypocretin-1 levels might be applied in the diagnosis of depression and the differential diagnosis of MDD and BD. The clear suicidal-ideation-related change found in hypocretin-1 levels in depression might be taken into account in the prevention of suicidal behaviour and further study of hypocretin-targeted therapies.

Blockade of NOP receptor modulates anxiety-related behaviors in mice exposed to inescapable stress

RATIONALE

Depression and anxiety frequently co-occur, and this has important clinical implications. Previous studies showed that activation of the nociceptin/orphanin FQ receptor (NOP) elicits anxiolytic effects, while its blockade promotes consistent antidepressant actions. NOP antagonists are effective in reversing footshock-induced depressive-like behaviors, but their effects on stress-induced anxiety are still unclear.

OBJECTIVE

This study aimed to investigate the effects of the NOP antagonist SB-612111 on footshock stress-induced anxiety behaviors.

METHODS

Male Swiss mice were exposed to inescapable electric footshock stress, and behavioral phenotype was screened based on the ability to escape from footshock (i.e., helpless or non-helpless). Animals were then treated with diazepam (1 mg/kg) and SB-612111 (0.1-10 mg/kg), and their behavior was assessed in the elevated plus-maze (EPM) and open field test.

RESULTS

When compared with non-stressed mice, helpless, but not non-helpless, animals displayed significant reductions in the time spent in and entries into open arms in the EPM. Diazepam significantly increased open arms exploration in helpless, non-helpless, and non-stressed mice. However, treatment with the NOP antagonist SB-612111 was inactive in naive mice, while it reversed anxiogenic-related behaviors in helpless mice and increased anxiety states in non-helpless mice. No effects on locomotion were observed.

CONCLUSION

Helpless mice displayed increased anxiety compared to non-stressed and non-helpless animals, thus supporting use of this approach as an animal model to investigate anxiety/depression comorbidity. Additionally, SB-612111 modulated anxiety-like behaviors in male mice depending on individual stress susceptibility. Ultimately, NOP antagonists could be useful for treating anxiety in depressed patients.

Personalized Psychiatry and Depression: The Role of Sociodemographic and Clinical Variables

Despite several pharmacological options, the clinical outcomes of major depressive disorder (MDD) are often unsatisfactory. Personalized psychiatry attempts to tailor therapeutic interventions according to each patient's unique profile and characteristics. This approach can be a crucial strategy in improving pharmacological outcomes in MDD and overcoming trial-and-error treatment choices. In this narrative review, we evaluate whether sociodemographic (i.e., gender, age, race/ethnicity, and socioeconomic status) and clinical [i.e., body mass index (BMI), severity of depressive symptoms, and symptom profiles] variables that are easily assessable in clinical practice may help clinicians to optimize the selection of antidepressant treatment for each patient with MDD at the early stages of the disorder. We found that several variables were associated with poorer outcomes for all antidepressants. However, only preliminary associations were found between some clinical variables (i.e., BMI, anhedonia, and MDD with melancholic/atypical features) and possible benefits with some specific antidepressants. Finally, in clinical practice, the assessment of sociodemographic and clinical variables considered in our review can be valuable for early identification of depressed individuals at high risk for poor responses to antidepressants, but there are not enough data on which to ground any reliable selection of specific antidepressant class or compounds. Recent advances in computational resources, such as machine learning techniques, which are able to integrate multiple potential predictors, such as individual/ clinical variables, biomarkers, and genetic factors, may offer future reliable tools to guide personalized antidepressant choice for each patient with MDD.

Antidepressive Mechanisms of Probiotics and Their Therapeutic Potential

The accumulating knowledge of the host-microbiota interplay gives rise to the microbiota-gut-brain (MGB) axis. The MGB axis depicts the interkingdom communication between the gut microbiota and the brain. This communication process involves the endocrine, immune and neurotransmitters systems. Dysfunction of these systems, along with the presence of gut dysbiosis, have been detected among clinically depressed patients. This implicates the involvement of a maladaptive MGB axis in the pathophysiology of depression. Depression refers to symptoms that characterize major depressive disorder (MDD), a mood disorder with a disease burden that rivals that of heart diseases. The use of probiotics to treat depression has gained attention in recent years, as evidenced by increasing numbers of animal and human studies that have supported the antidepressive efficacy of probiotics. Physiological changes observed in these studies allow for the elucidation of probiotics antidepressive mechanisms, which ultimately aim to restore proper functioning of the MGB axis. However, the understanding of mechanisms does not yet complete the endeavor in applying probiotics to treat MDD. Other challenges remain which include the heterogeneous nature of both the gut microbiota composition and depressive symptoms in the clinical setting. Nevertheless, probiotics offer some advantages over standard pharmaceutical antidepressants, in terms of residual symptoms, side effects and stigma involved. This review outlines antidepressive mechanisms of probiotics based on the currently available literature and discusses therapeutic potentials of probiotics for depression.

Translational Studies in the Complex Role of Neurotransmitter Systems in Anxiety and Anxiety Disorders

Discovery of innovative anxiolytics is severely hampering. Existing anxiolytics are developed decades ago and are still the therapeutics of choice. Moreover, lack of new drug targets forecasts a severe jeopardy in the future treatment of the huge population of CNS-diseased patients. We simply lack the knowledge on what is wrong in brains of anxious people (normal and diseased). Translational research, based on interacting clinical and preclinical research, is extremely urgent. In this endeavor, genetic and genomic approaches are part of the spectrum of contributing factors. We focus on three druggable targets: serotonin transporter, 5-HT_1A, and GABA_A receptors. It is still uncertain whether and how these targets are involved in normal and diseased anxiety processes. For serotonergic anxiolytics, the slow onset of action points to indirect effects leading to plasticity changes in brain systems leading to reduced anxiety. For GABA_A benzodiazepine drugs, acute anxiolytic effects are found indicating primary mechanisms directly influencing anxiety processes. Close translational collaboration between fundamental academic and discovery research will lead to badly needed breakthroughs in the search for new anxiolytics.

Management of Treatment-Resistant Depression: Challenges and Strategies

Treatment-resistant depression (TRD) is a subset of Major Depressive Disorder which does not respond to traditional and first-line therapeutic options. There are several definitions and staging models of TRD and a consensus for each has not yet been established. However, in common for each model is the inadequate response to at least 2 trials of antidepressant pharmacotherapy. In this review, a comprehensive analysis of existing literature regarding the challenges and management of TRD has been compiled. A PubMed search was performed to assemble meta-analyses, trials and reviews on the topic of TRD. First, we address the confounds in the definitions and staging models of TRD, and subsequently the difficulties inherent in assessing the illness. Pharmacological augmentation strategies including lithium, triiodothyronine and second-generation antipsychotics are reviewed, as is switching of antidepressant class. Somatic therapies, including several modalities of brain stimulation (electroconvulsive therapy, repetitive transcranial magnetic stimulation, magnetic seizure therapy and deep brain stimulation) are detailed, psychotherapeutic strategies and subsequently novel therapeutics including ketamine, psilocybin, anti-inflammatories and new directions are reviewed in this manuscript. Our review of the evidence suggests that further large-scale work is necessary to understand the appropriate treatment pathways for TRD and to prescribe effective therapeutic options for patients suffering from TRD.

Treatment resistant depression in women with peripartum depression

BACKGROUND

Peripartum depression is a leading cause of disease burden for women and yet there is little evidence as to how often peripartum depression does not respond to treatment and becomes treatment resistant depression. We sought to determine the incidence of treatment resistant depression (TRD) in women with peripartum depression.

METHODS

Population based retrospective cohort study using a large US claims database. Peripartum depression was defined as having a depression diagnosis during pregnancy or up to 6 months after the end of pregnancy. We included women with prevalent or incident depression. The outcome was the development of TRD within 1 year after the diagnosis of peripartum depression. TRD was defined as having 3 distinct antidepressants or 1 antidepressant and 1 antipsychotic in 1 year. Women with peripartum depression may not be exposed to pharmacological treatments early in pregnancy, therefore we created two groups: 1. women with peripartum depression, and 2. women with peripartum depression diagnosed 3 months before a live birth delivery or within 6 months after that delivery.

RESULTS

There were 3,207,684 pregnant women, of whom 2.5% had peripartum depression. Of these women half had incident depression during pregnancy. Five percent of women with peripartum depression developed TRD within 1 year of the depression diagnosis. The risk of developing TRD was 50% higher in women with prevalent depression than in women with incident peripartum depression (P < 0.0001). Results were similar in women with peripartum depression diagnosed later in their pregnancy. Women who went on to develop TRD had more substance use disorders, anxiety, insomnia and painful conditions.

CONCLUSIONS

TRD occurs in approximately 5% of women with peripartum depression. The risk of TRD is higher in pregnant women with a history of depression. Women who went on to develop TRD had more psychiatric comorbidities and painful conditions than women who did not.

Characterising anxiety in major depressive disorder and its use in predicting antidepressant treatment outcome: An iSPOT-D report

OBJECTIVE

Major depressive disorder commonly co-occurs with one or more anxiety disorders or with clinically significant levels of anxiety symptoms. Although evidence suggests that anxious forms of depression are prognostic of poorer antidepressant outcomes, there is no clear definition of anxious depression, and inferences about clinical outcomes are thus limited. Our objective was to compare and evaluate definitions of anxious depression and anxiety-related scales according to clinical and antidepressant outcome criteria.

METHOD

A total of 1008 adults with a current diagnosis of single-episode or recurrent, nonpsychotic, major depressive disorder were assessed at baseline on clinical features. Participants were then randomised to one of three antidepressants and reassessed at 8 weeks regarding remission and response of the 17-item Hamilton Rating Scale Depression (HRSD₁₇) and the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR₁₆). Anxious depression was defined as major depressive disorder with one or more anxiety disorders or major depressive disorder with a HRSD₁₇ anxiety/somatisation factor score ⩾7. Anxiety-related scales included the HRSD₁₇ anxiety/somatisation factor and the 42-item Depression Anxiety Stress Scales (DASS₄₂) anxiety and stress subscales.

RESULTS

Anxious depression definitions showed poor agreement (κ = 0.15) and the HRSD₁₇ anxiety/somatisation factor was weakly correlated with both DASS₄₂ anxiety (r = 0.24) and stress subscales (r = 0.20). Anxious depression definitions were also associated with few impairments on clinical features and did not predict poorer antidepressant treatment outcome. However, higher DASS₄₂ anxiety predicted poorer HRSD₁₇ and QIDS-SR₁₆ remission, and item-level analysis found higher scores on items 9 (situational anxiety) and 23 (somatic anxiety) of the DASS₄₂ predicted poorer treatment outcome, even after adjusting for covariates and multiple comparisons.

CONCLUSION

Common definitions of anxious depression show poor agreement and do not predict poorer treatment outcome. Anxiety symptoms may be better characterised dimensionally using DASS₄₂ when predicting treatment outcome.

The role of anxious distress in immune dysregulation in patients with major depressive disorder

Although depression with anxious distress appears to be a clinically relevant subtype of major depressive disorder (MDD), whether it involves specific pathophysiology remains unclear. Inflammation has been implicated, but not comprehensively studied. We examined within a large MDD sample whether anxious distress and related anxiety features are associated with differential basal inflammation and innate cytokine production capacity. Data are from 1078 MDD patients from the Netherlands Study of Depression and Anxiety. In addition to the DSM-5 anxious distress specifier, we studied various dimensional anxiety scales (e.g. Inventory of Depressive Symptomatology anxiety arousal subscale [IDS-AA], Beck Anxiety Inventory [BAI], Mood and Anxiety Symptoms Questionnaire Anxious Arousal scale [MASQ-AA]). The specifier was constructed using five self-report items from the IDS and BAI. Basal inflammatory markers included C-reactive protein (CRP), interleukin (IL)-6 and tumor necrosis factor (TNF)-α. Innate production capacity was assessed by 13 lipopolysaccharide (LPS)-stimulated inflammatory markers. Basal and LPS-stimulated inflammation index scores were created. Basal inflammation was not associated with anxious distress (prevalence = 54.3%) in MDD patients, except for a modest positive association for BAI score. However, anxious distress was associated with higher LPS-stimulated levels (interferon-γ, IL-6, monocyte chemotactic protein (MCP)-1, macrophage inflammatory protein (MIP)-1α, matrix metalloproteinase (MMP)-2, TNF-α, LPS-stimulated index). Other anxiety indicators (anxious distress specifier score, BAI, MASQ-AA) were also associated with increased innate production capacity. Within a large MDD sample, the anxious distress specifier was associated with increased innate cytokine production capacity but not with basal inflammation. Results from dimensional anxiety indicators largely confirm these results. These findings provide new insight into the pathophysiology of anxious depression.

Experimental medication treatment approaches for depression

Depression is one of the most common psychiatric conditions. Symptoms can lead to significant disability, which result in impairments in overall quality of life. Though there are many approved antidepressant treatments for depression-including selective serotonin reuptake inhibitors, tricyclic antidepressants and monoamine oxidase inhibitors-about a third of patients do not respond to these medications. Therefore, it is imperative for drug discovery to continue towards the development of novel and rapidly acting compounds, especially for patients with treatment-resistant depression. After a brief review of the efficacy of approved antidepressant therapies, we will discuss experimental medication treatments for depression. Specifically, we examine novel medications that are thought to primarily modulate the glutamatergic, cholinergic and opioid systems to achieve antidepressant efficacy. We also give examples of anti-inflammatories, neurokinin-1 modulators, vasopressin antagonists and neurogenesis enhancers that may have a therapeutic role in treatment-resistant depression. The current pipeline of antidepressant treatments is shifting towards medications with novel mechanisms, which may lead to important, life-changing discoveries for patients with severe disease.

The Role of Chronic Stress in Anxious Depression

Depression is a heterogeneous disease with many different subtypes. Patients with the anxious depression-a common subtype of major depression-are at an increased risk for treatment-resistance to standard antidepressants, with resultant increases in morbidity. However, the underlying pathophysiology of anxious depression remains unknown. Without such knowledge, the development of targeted treatments towards this specific depression subtype will likely remain elusive. One method by which research into the neurobiology of anxious depression may prove fruitful is with the research domain criteria (RDoC). RDoC provides a framework for investigation into the underlying pathophysiology of mental illness. By studying disorders in terms of RDoC constructs-such as the sustained threat construct of the negative valence system-new insights may be gained into neurobiological mechanisms of disease. These mechanisms may be useful for the development of novel antidepressants that are based on specific brain targets. Specifically, we review the impact that sustained threat-or chronic stress-has on the eventual development of depression (especially anxious depression) through pathological changes to molecules, cells, neurocircuitry, physiology, and behavior.

Ziprasidone augmentation for anxious depression

Previously, we found an anxiolytic effect of ziprasidone augmentation to escitalopram (compared with placebo augmentation) in patients with depression in an 8-week, randomized, double-blind, parallel-group, placebo-controlled trial. Here, we carried out a post-hoc analysis, comparing changes in the Hamilton Depression and Anxiety Rating Scales between patients with anxious depression versus nonanxious depression, using a moderator analysis. Hamilton Depression Rating Scales total change scores from baseline and endpoint were not significantly different (interaction term P=0.91) in patients with anxious depression on ziprasidone augmentation (n=19; -9.1±4.9) or placebo (n=19; -6.1±8.9) versus patients without anxious depression on ziprasidone (n=52; -5.5±6.7) or placebo (n=49; -2.3±4.5). There was a trend toward statistical significance (interaction term P=0.1) in favor of patients without anxious depression for a difference in Hamilton Anxiety Rating Scale total change scores from baseline to endpoint [patients with anxious depression on ziprasidone augmentation (n=19; -2.7±5.3) or placebo (n=19; -3.3±5.8) versus patients without anxious depression on ziprasidone (n=51; -3.9±6.6) or placebo (n=44; -0.9±4.7)]. Ziprasidone augmentation was equally efficacious in treating depression in patients with versus without anxious depression. However, the observed anxiolytic effect for patients with higher anxiety was not clinically significant.

Recognition of emotional facial expressions in anxious and nonanxious depression

BACKGROUND

Anxiety and depression have each been independently associated with impairments in emotional face recognition. However, little is known about the nature of these impairments when anxiety and depression co-occur.

METHODS

This post-hoc analysis evaluated the relationship between anxiety status and performance on the Emotional Expression Multimorph Task within a clinical sample of individuals with major depressive disorder (MDD).

RESULTS

Participants with anxious depression (n=14) and nonanxious depression (n=14) completed the Emotional Expression Multimorph Task. Those with anxious depression required greater intensity of emotion to identify both happy (p=.01) and sad (p=.04) facial expressions than those with nonanxious depression. Severity of anxiety also correlated with greater intensity of emotion required to detect sad faces. Contrary to prediction, hypervigilance to angry and fearful facial expressions was not observed in anxious depression.

LIMITATIONS

The present study did not include an anxiety-only group for comparison, and did not assess state anxiety at time of administration. In addition, the extent to which the experimental task correlates with social functioning is not fully understood.

CONCLUSIONS

These findings suggest a diminished sensitivity to happy and sad facial expressions specific to anxious depression, but not a hypervigilance toward threatening facial expressions. Further research on the nature of emotion recognition in anxiety and depression may inform improved clinical interventions.

Adjunctive brexpiprazole in patients with major depressive disorder and anxiety symptoms: an exploratory study

BACKGROUND

Major depressive disorder (MDD) with concurrent anxiety symptoms may signal a difficult-to-treat patient. Brexpiprazole is a serotonin-dopamine activity modulator: a partial agonist at 5-HT_1A and dopamine D₂ receptors at similar potency, and an antagonist at 5-HT_2A and noradrenaline alpha_1B/2C receptors. The objective of this Phase IIIb study was to explore effectiveness, safety, and tolerability of brexpiprazole adjunctive to antidepressant (ADT) monotherapy in patients with MDD and anxiety symptoms (NCT02013531).

METHODS

Patients with MDD, Hamilton Anxiety Rating Scale (HAM-A) total score ≥ 20, and inadequate response to current ADT received open-label brexpiprazole 1-3 mg day^-1 (target dose 2 mg day^-1) + ADT for 6 weeks. Efficacy endpoints included change from baseline at Week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score, HAM-A total score, and Sheehan Disability Scale (SDS). Safety and tolerability assessments included adverse events (AEs).

RESULTS

Of 37 participants enrolled, 32 (86.5%) completed the study. Baseline mean (SD) MADRS total score was 30.1 (5.1); mean HAM-A total score was 26.9 (5.0). Improvements from baseline were observed at Week 6 for least squares mean change in MADRS total score (-19.6, p < .0001 vs. baseline), HAM-A total score (-17.8, p < .0001) and mean (SD) SDS mean score [-3.6 (2.6)]. Brexpiprazole was well tolerated. The most frequent treatment-emergent AEs were increased appetite (13.5%) and diarrhea, dry mouth, and dizziness (all 10.8%).

CONCLUSIONS

These open-label results support the anxiolytic effects of adjunctive brexpiprazole in the treatment of patients with MDD.

Pharmacological approaches to the challenge of treatment-resistant depression

Although monoaminergic antidepressants revolutionized the treatment of Major Depressive Disorder (MDD) over a half-century ago, approximately one third of depressed patients experience treatment-resistant depression (TRD). Such patients account for a disproportionately large burden of disease, as evidenced by increased disability, cost, human suffering, and suicide. This review addresses the definition, causes, evaluation, and treatment of unipolar TRD, as well as the major treatment strategies, including optimization, augmentation, combination, and switch therapies. Evidence for these options, as outlined in this review, is mainly focused on large-scale trials or meta-analyses. Finally, we briefly review emerging targets for antidepressant drug discovery and the novel effects of rapidly acting antidepressants, with a focus on ketamine.

A randomized, placebo-controlled pilot trial of the delta opioid receptor agonist AZD2327 in anxious depression

RATIONALE

Patients with anxious major depressive disorder (AMDD) have more severe symptoms and poorer treatment response than patients with non-AMDD. Increasing evidence implicates the endogenous opioid system in the pathophysiology of depression. AZD2327 is a selective delta opioid receptor (DOR) agonist with anxiolytic and antidepressant activity in animal models.

OBJECTIVE

This double-blind, parallel group design, placebo-controlled pilot study evaluated the safety and efficacy of AZD2327 in a preclinical model and in patients with AMDD.

METHODS

We initially tested the effects of AZD2327 in an animal model of AMDD. Subsequently, 22 subjects with AMDD were randomized to receive AZD2327 (3 mg BID) or placebo for 4 weeks. Primary outcome measures included the Hamilton Depression Rating Scale (HAM-D) and the Hamilton Anxiety Rating Scale (HAM-A). We also evaluated neurobiological markers implicated in mood and anxiety disorders, including vascular endothelial growth factor (VEGF) and electroencephalogram (EEG).

RESULTS

Seven (54 %) patients responded to active drug and three (33 %) responded to placebo. No significant main drug effect was found on either the HAM-D (p = 0.39) or the HAM-A (p = 0.15), but the HAM-A had a larger effect size. Levels of AZ12311418, a major metabolite of AZD2327, were higher in patients with an anti-anxiety response to treatment compared to nonresponders (p = 0.03). AZD2327 treatment decreased VEGF levels (p = 0.02). There was a trend (p < 0.06) for those with an anti-anxiety response to have higher EEG gamma power than nonresponders.

CONCLUSION

These results suggest that AZD2327 has larger potential anxiolytic than antidepressant efficacy. Additional research with DOR agonists should be considered.

A Randomized Controlled Trial of Mindfulness-Based Cognitive Therapy for Treatment-Resistant Depression

BACKGROUND

Due to the clinical challenges of treatment-resistant depression (TRD), we evaluated the efficacy of mindfulness-based cognitive therapy (MBCT) relative to a structurally equivalent active comparison condition as adjuncts to treatment-as-usual (TAU) pharmacotherapy in TRD.

METHODS

This single-site, randomized controlled trial compared 8-week courses of MBCT and the Health Enhancement Program (HEP), comprising physical fitness, music therapy and nutritional education, as adjuncts to TAU pharmacotherapy for outpatient adults with TRD. The primary outcome was change in depression severity, measured by percent reduction in the total score on the 17-item Hamilton Depression Rating Scale (HAM-D17), with secondary depression indicators of treatment response and remission.

RESULTS

We enrolled 173 adults; mean length of a current depressive episode was 6.8 years (SD = 8.9). At the end of 8 weeks of treatment, a multivariate analysis showed that relative to the HEP condition, the MBCT condition was associated with a significantly greater mean percent reduction in the HAM-D17 (36.6 vs. 25.3%; p = 0.01) and a significantly higher rate of treatment responders (30.3 vs. 15.3%; p = 0.03). Although numerically superior for MBCT than for HEP, the rates of remission did not significantly differ between treatments (22.4 vs. 13.9%; p = 0.15). In these models, state anxiety, perceived stress and the presence of personality disorder had adverse effects on outcomes.

CONCLUSIONS

MBCT significantly decreased depression severity and improved treatment response rates at 8 weeks but not remission rates. MBCT appears to be a viable adjunct in the management of TRD.

Psychiatric Comorbidity in Alcohol Dependence

We review our clinical studies of psychiatric comorbidity in short-term and long-term abstinent and in treatment naïve alcoholics (STAA, LTAA and TNA). TNA ypically have less severe alcoholism than treated abstinent samples and evidence less severe psychiatric disturbance. Lifetime psychiatric diagnoses are the norm for STAA and LTAA but not for TNA. Individuals with alcohol and drug use disorders show greater antisocial personality disturbance, but do not show differences in the mood or anxiety domains or in borderline personality disorder (BPD) symptoms. The studies show that alcoholics can achieve and maintain abstinence in the face of ongoing mood, anxiety, or BPD problems. By contrast, for ASPD, LTAA essentially stop current antisocial behaviors in all seven domains of antisocial behaviors. We believe that ongoing antisocial behavior is not consistent with maintaining abstinence, and that LTAA modify their antisocial behavior despite continued elevated social deviance proneness and antisocial dispositionality. Abstinent individuals without lifetime psychiatric disorders and TNA show more (subdiagnostic threshold) psychiatric symptoms and abnormal psychological measures than non-alcoholic controls in the mood, anxiety, BPD, and antisocial domains. In summary, our studies show that although LTAA have achieved multi-year abstinence, they still report significant psychological distress compared to NAC. We believe this distress may negatively affect their quality of life. This suggests the importance of developing effective care models to address comorbid mental health problems in LTAA. We also show that antisocial personality disorder symptoms decline to the levels seen in normal controls, and that excluding individuals from research with a psychiatric diagnosis does not control for subdiagnostic psychiatric differences between alcoholics and controls.

Towards new mechanisms: an update on therapeutics for treatment-resistant major depressive disorder

Depression is a devastating disorder that places a significant burden on both the individual and society. As such, the discovery of novel therapeutics and innovative treatments--especially for treatment-resistant depression (TRD)--are essential. Research into antidepressant therapies for TRD has evolved from explorations of antidepressants with primary mechanisms of action on the monoaminergic neurotransmitter system to augmentation agents with primary mechanisms both within and outside of the serotonin/norepinephrine system. Now the field of antidepressant research has changed trajectories yet again; this time, compounds with primary mechanisms of action on the glutamatergic, cholinergic and opioid systems are in the forefront of antidepressant exploration. In this review, we will discuss the most recent research surrounding these novel compounds. In addition, we will discuss novel device-based therapeutics, with a particular focus on transcranial magnetic stimulation. In many cases of antidepressant drug discovery, the role of serendipity coupled with meticulous clinical observation in drug development in medicine was crucial. Moving forward, we must look toward the combination of innovation plus improvements on the remarkable discoveries thus far to advance the field of antidepressant research.

Pharmacological approaches to the challenge of treatment-resistant depression

Although monoaminergic antidepressants revolutionized the treatment of Major Depressive Disorder (MDD) over a half-century ago, approximately one third of depressed patients experience treatment-resistant depression (TRD). Such patients account for a disproportionately large burden of disease, as evidenced by increased disability, cost, human suffering, and suicide. This review addresses the definition, causes, evaluation, and treatment of unipolar TRD, as well as the major treatment strategies, including optimization, augmentation, combination, and switch therapies. Evidence for these options, as outlined in this review, is mainly focused on large-scale trials or meta-analyses. Finally, we briefly review emerging targets for antidepressant drug discovery and the novel effects of rapidly acting antidepressants, with a focus on ketamine.