Psychosocial and neurocognitive functioning in unipolar and bipolar depression: a 12-month prospective study

Identifying the core residual symptom in patients with major depressive disorder using network analysis and illustrating its association with prognosis: A study based on the national cohorts in China

OBJECTIVE

To identify the core residual symptom of MDD and assess its relationship with patients' long-term outcomes.

METHOD

All patients were administered antidepressants during the acute phase and treated continuously. The 521 patients remitted at month 6 of a multicenter prospective project were included. Remission was defined as a Quick Inventory of Depressive Symptoms-Self-Report total score of ≤5. Functional impairments were measured with the Sheehan Disability Scale, quality of life with the Quality of Life Enjoyment and Satisfaction Questionnaire - short form, and family burden with the Family Burden Scale of Disease. Visits were scheduled at baseline, weeks 2, 8, 12, and month 6.

RESULTS

Difficulty with concentration/decision making was the core residual symptom of MDD, determined with the centrality measure of network analysis. It was positively associated with functional impairments and family burden (r = 0.35, P < 0.01 and r = 0.31, P < 0.01, respectively) and negatively associated with life satisfaction (r = -0.29, P < 0.01). The exhibition of this residual symptom was associated with a family history of psychiatric disorders (OR = 2.610 [1.242-5.485]).

CONCLUSIONS

The core residual symptom of MDD, difficulty with concentration/decision making, is associated with poorer social functioning, heavier family burden, and lower life satisfaction. Early detection and intervention of this symptom may be beneficial.

CLINICAL TRIALS REGISTRATION NUMBER

(Chinese Clinical Trials.gov identifier) ChiCTR-OOC-17012566 and ChiCTR-INR-17012574.

Common mental health disorders and cognitive decline in a longitudinal Down syndrome cohort

BACKGROUND

Down syndrome is the most common genetic cause of intellectual disability and Alzheimer's disease. In the general population, common mental disorders (CMDs), including anxiety, depression and obsessive-compulsive disorder, are linked to cognitive decline and higher risk for dementia. It is not known how CMDs affect longer-term cognitive outcomes in Down syndrome, and there is often diagnostic uncertainty in older people with Down syndrome and psychiatric comorbidity.

AIMS

To study the influence of CMDs on cognitive ability and whether they are related longitudinally to development of clinical signs of Alzheimer's disease in Down syndrome.

METHOD

We followed 115 individuals with Down syndrome, 27 of whom were diagnosed with a CMD, over approximately 3 years. Changes in cognitive and behavioural outcomes between baseline and follow-up assessment were analysed, with comparisons made between those with and without a comorbid CMD. Age, gender, apolipoprotein E status and level of intellectual disability were included as covariates.

RESULTS

No significant association between presence of a CMD and poorer performance on cognitive tasks or informant-rated decline over time was observed (P > 0.05).

CONCLUSIONS

Our results suggest that a diagnosis of a CMD does not have a significant negative effect on long-term cognitive or behavioural outcomes in individuals with Down syndrome. In individuals with stable or treated CMD, subsequent cognitive decline is likely indicative of Alzheimer's disease rather than a consequence of mental disorder.

If you feel you can't, you won't: the role of subjective and objective cognitive competence on psychosocial functioning in depression

BACKGROUND

The purpose of this exploratory study is to examine the role of sociodemographic, clinical, and cognitive - both objective and subjective - factors in overall and in specific domains of psychosocial functioning, in patients with depression at different clinical states of the disease (remitted and non-remitted).

METHODS

A sample of 325 patients with major depressive disorder, 117 in remission and 208 in non-remission, were assessed with a semi-structured interview collecting sociodemographic, clinical, cognitive (with neuropsychological tests and the Perceived Deficit Questionnaire), and functional (Functioning Assessment Short Test) characteristics. Backward regression models were conducted to determine associations of global and specific areas of functioning with independent factors, for both clinical states.

RESULTS

Residual depressive symptomatology and self-appraisal of executive competence were significantly associated with psychosocial functioning in remitted patients, in overall and some subdomains of functioning, particularly cognitive and interpersonal areas. While depressive symptoms, executive deficits and self-appraisal of executive function were significantly related to functional outcomes in non-remitted patients, both in overall functioning and in most of subdomains.

DISCUSSION

This study evidences the strong association of one's appraisal of executive competence with psychosocial functioning, together with depressive symptoms, both in remitted and non-remitted patients with depression. Therefore, to achieve full recovery, clinical management of patients should tackle not only the relief of core depressive symptoms, but also the cognitive ones, both those that are objectified with neuropsychological tests and those that are reported by the patients themselves.

Differences in Selective Attention and Inhibitory Control in Patients with Major Depressive Disorder and Healthy Controls Who Do Not Engage in Sufficient Physical Activity

BACKGROUND

Patients with major depressive disorder (MDD) are characterized by neurocognitive impairments and show deficits in various cognitive performance indicators, including executive function. We examined whether sustained attention and inhibitory control differ between patients with MDD and healthy controls, and whether differences exist between patients with mild, moderate, and severe depression.

METHODS

Clinical in-patients (N = 212) aged 18-65 years with a current diagnosis of MDD and 128 healthy controls were recruited. Depression severity was assessed using the Beck Depression Inventory, and sustained attention and inhibitory control were assessed using the oddball and flanker tasks. The use of these tasks promises insights into executive function in depressive patients that are not biased by verbal skills. Group differences were tested via analyses of covariance.

RESULTS

Patients with MDD showed slower reaction times in both the oddball and flanker task, independent of the executive demands of the trial types. Younger participants achieved shorter reaction times in both inhibitory control tasks. After correcting for age, education, smoking, BMI, and nationality, only differences in reaction times in the oddball task were statistically significant. In contrast, reaction times were not sensitive to the symptom severity of depression.

CONCLUSION

Our results corroborate deficits in basic information processing and specific impairments in higher-order cognitive processes in MDD patients. As difficulties in executive function underlie problems in planning, initiating, and completing goal-directed activities, they may jeopardize in-patient treatment and contribute to the recurrent nature of depression.

Neurocognition and Depressive Symptoms have Unique Pathways to Predicting Different Domains of Functioning in Major Depressive Disorder

BACKGROUND

Research has established the independent relationships between depressive symptoms to cognition and functioning in depression; however, little is known about the role of mediators in this relationship. We explored the role of neurocognitive abilities, depressive symptom severity, dysfunctional attitudes, and functional capacity in predicting two dimensions of daily functioning in individuals with major depressive disorder (MDD).

METHODS

One hundred and twenty-four participants (mean age  =  46.26, SD  =  12.27; 56% female) with a diagnosis of MDD were assessed on a standard neurocognitive battery, self-reported depressive symptoms, dysfunctional attitudes, and clinician-rated functional impairment. They completed a performance-based assessment of functional competence.

RESULTS

Confirmatory path analyses were used to model the independent and mediated effects of variables on two domains of functioning: social (relationships and social engagement) and productive (household and community activities). Cognition and depressive symptoms both predicted productive functioning, and dysfunctional attitudes mediated each of these relationships. Functional competence was a significant mediator in the relationship between neurocognition and productive functioning. Depressive symptoms and cognition were direct predictors of social functioning with no significant mediators.

CONCLUSIONS

There are divergent pathways to different dimensions of daily functioning in MDD. Measurement implications include the consideration of multiple levels of predicting productive activities and more direct relationships with social outcomes. Treatments that directly target depressive symptoms and cognition might not generalize to improvements in everyday functioning if additional pathways to functioning are not addressed.

Predictors of functional outcome in patients with major depression and bipolar disorder: A dynamic network approach to identify distinct patterns of interacting symptoms

The purpose of this study is to use a dynamic network approach as an innovative way to identify distinct patterns of interacting symptoms in patients with Major Depressive Disorder (MDD) and patients with Bipolar Type I Disorder (BD). More precisely, the hypothesis will be testing that the phenotype of patients is driven by disease specific connectivity and interdependencies among various domains of functioning even in the presence of underlying common mechanisms. In a prospective observational cohort study, hundred-forty-three patients were recruited at the Psychiatric Clinic "Villa dei Gerani" (Catania, Italy), 87 patients with MDD and 56 with BD with a depressive episode. Two nested sub-groups were treated for a twelve-week period, which allowed us to explore differences in the pattern of symptom distribution (central vs. peripheral) and their connectedness (strong vs weak) before (T0) and after (T1) treatment. All patients underwent a complete neuropsychological evaluation at baseline (T0) and at T1. A network structure was computed for MDD and BD patients at T0 and T1 from a covariance matrix of 17 items belonging to three domains-neurocognitive, psychosocial, and mood-related (affective) to identify what symptoms were driving the networks. Clinically relevant differences were observed between MDD and BD, at T0 and after 12 weeks of pharmacological treatment. At time T0, MDD patients displayed an affective domain strongly connected with the nodes of psychosocial functioning, while direct connectivity of the affective domain with the neurocognitive cluster was absent. The network of patients with BD, in contrast, revealed a cluster of highly interconnected psychosocial nodes but was guided by neurocognitive functions. The nodes related to the affective domain in MDD are less connected and placed in the periphery of the networks, whereas in BD they are more connected with psychosocial and neurocognitive nodes. Noteworthy is that, from T0 to T1 the "Betweenness" centrality measure was lower in both disorders which means that fewer "shortest paths" between nodes pass through the affective domain. Moreover, fewer edges were connected directly with the nodes in this domain. In MDD patients, pharmacological treatment primarily affected executive functions which seem to improve with treatment. In contrast, in patients with BD, treatment resulted in improvement of overall connectivity and centrality of the affective domain, which seems then to affect and direct the overall network. Though different network structures were observed for MDD and BD patients, data suggest that treatment should include tailored cognitive therapy, because improvement in this central domain appeared to be fundamental for better outcomes in other domains. In sum, the advantage of network analysis is that it helps to predict the trajectory of future phenotype related disease manifestations. In turn, this allows new insights in how to balance therapeutic interventions, involving different fields of function and combining pharmacological and non-pharmacological treatment modalities.

Convergent and divergent cognitive impairment of unipolar and bipolar depression: A magnetoencephalography resting-state study

BACKGROUND

Unipolar depression (UD) and bipolar depression (BD) showed convergent and divergent cognitive impairments. Neural oscillations are linked to the foundational cognitive processes. We aimed to investigate the underpinning spectral neuronal power patterns by magnetoencephalography (MEG), which combinates high spatial and temporal resolution. We hypothesized that patients with UD and BD exhibit common and distinct patterns, which may contribute to their cognitive impairments.

METHODS

Group cognitive tests were performed. Eyes closed resting-state MEG data were collected from 61 UD, 55 BD, and 52 healthy controls (HC). Nonparametric cluster-based permutation tests were performed to deal with the multiple comparison problem on channel-frequency MEG data. Correlation analysis of cognitive dysfunction scores and MEG oscillation were conducted by Spearman or partial correlation analysis.

RESULTS

Wisconsin Card Sorting Test showed similar cognitive impairment in patients with UD and BD. Moreover, patients with BD exhibited extensive cognitive deficits in verbal executive functions and visuospatial processing. Compare to HC, both patients with UD and BD showed increased frontal-central beta power while high gamma power was decreased in UD groups during the resting-state. The significant correlations between cognitive function and average beta power were observed.

CONCLUSIONS

Patients with BD had more cognitive impairments on different dimensions than those with UD, involving disrupted beta power modulations. Our investigation provides a better understanding of the neuroelectrophysiological process underlying cognitive impairments in patients with UD and BD.

The prevalence and characteristics of MCCB cognitive impairment in unmedicated patients with bipolar II depression and major depressive disorder

BACKGROUND

Cognitive impairment has been acknowledged as a core clinical manifestation of bipolar disorder (BD) as well as major depressive disorder (MDD). Determining the prevalence and characteristics of cognitive impairment is important for clinical interventions. This study investigated the prevalence and characteristics of cognitive impairment based on the Measurement and Treatment Research to Improve Cognition Schizophrenia Consensus Cognitive Battery (MCCB) in both BD and MDD.

METHOD

One hundred and forty-nine BD II depression, 147 MDD, and 124 demographically matched healthy controls (HC) underwent MCCB cognitive assessment. The prevalence of MCCB cognitive impairment and group difference comparisons were performed. Additionally, association analysis was performed to investigate the relationship between cognitive performance and clinical variables.

RESULTS

Compared to the HC group, both BD II depression and MDD groups had a significantly reduced performance for all MCCB cognitive domains (all p < 0.05). The numerical scores for visual learning were lower in the BD II depression group compared to the MDD group. 32.89% of the BD II depression patients had clinically significant impairment (>1.5 SD below the normal mean) in two or more MCCB domains compared to 23.13% for MDD patients.

CONCLUSIONS

A high percent of patients in the BD II depression and MDD group exhibited MCCB cognitive impairments with clinical significance. Cognitive impairments were more common in BD II depression patients compared to MDD patients, particularly for visual learning. These findings suggest that clinicians should be aware of the severe cognitive impairment in mood disorders and establish effective cognitive screening and intervention strategies.

Socioeconomic and substance use changes in emerging adults and their relationship with mood disorders in a population-based cohort

In this report, we aim to assess the interaction of bipolar disorder and major depressive disorder with the evolution of social roles, economic classification, and substance misuse in emerging adults. This is a longitudinal population-based study (n = 231 at baseline), in which participants were reassessed at a mean of 5 years after baseline. A structured clinical interview was used to diagnose the participants with bipolar disorder and major depression; a control group without mood disorders was included. Men with mood disorders were less likely to be married in the beginning of the study and less likely to work in the follow-up. Women with major depression were less likely to study and more likely to be in a lower economic class at the beginning of the study. In comparison, women with bipolar disorder were less likely to live with their parents and more likely to live with their children in the first wave of the study. Substance misuse was more likely in people with mood disorders, especially in men, and women with bipolar disorder had the highest likelihood in the follow-up. Albeit longitudinal analyses were limited by a possibly insufficient sample size and mediating mechanisms for change, such as stigma, were not explored, the study suggests sex-related specificities regarding the change in social roles and substance use in people with mood disorders. Emerging adults, especially those with mood disorders, are in a period of change and instability and at a greater risk for substance use and abuse.

Behavioural and neurophysiological differences in working memory function of depressed patients and healthy controls

OBJECTIVE

Major depressive disorder (MDD) is associated with deficits in working memory. Several cognitive subprocesses interact to produce working memory, including attention, encoding, maintenance and manipulation. We sought to clarify the contribution of functional deficits in these subprocesses in MDD by varying cognitive load during a working memory task.

METHODS

41 depressed participants and 41 age and gender-matched healthy controls performed the n-back working memory task at three levels of difficulty (0-, 1-, and 2-back) in a pregistered study. We assessed response times, accuracy, and event-related electroencephalography (EEG), including P2 and P3 amplitudes, and frontal theta power (4-8 Hz).

RESULTS

MDD participants had prolonged response times and more positive frontal P3 amplitudes (i.e., Fz) relative to controls, mainly in the most difficult 2-back condition. Working memory accuracy, P2 amplitudes and frontal theta event-related synchronisation did not differ between groups at any level of task difficulty.

CONCLUSIONS

Depression is associated with generalized psychomotor slowing of working memory processes, and may involve compensatory hyperactivity in frontal and parietal regions.

SIGNIFICANCE

These findings provide insights into MDD working memory deficits, indicating that depressed individuals dedicate greater levels of cortical processing and cognitive resources to achieve comparable working memory performance to controls.

Cognitive Profile and Relationship with Quality of Life and Psychosocial Functioning in Mood Disorders

BACKGROUND

Comparisons between healthy controls (HCs) and individuals with mood disorders have shown more cognitive dysfunction among the latter group, in particular in bipolar disorder (BD). This study aimed to characterize the pattern of cognitive function of BD and major depressive disorder (MDD) and compare them to HC using the (CogState Research Battery) CSRB™.

METHOD

Participants were tested, comprising the following domains: processing speed, attention, working memory, visual memory, executive functions, and verbal memory. Quality of life and functionality were also assessed. Multiple linear regression models were performed to examine the effect of demographic characteristics and functionality on cognitive outcomes separately for BD and MDD.

RESULTS

Ninety individuals participated in the study, of which 32 had BD, 30 had MDD, and 28 were HC. Differences were found between both BD and MDD and HC for the composite cognitive score, with significant differences between BD and HC (Diff = -5.5, 95% CI = [-9.5, -1.5], p = 0.005), and MDD and HC (Diff = -4.6, 95% CI = [-8.6, -0.5], p = 0.025). There were overall significant differences in five cognitive domains: processing speed (p = 0.001 and p = 0.004), attention (p = 0.002), working memory (p = 0.02), visual memory (p = 0.021), and verbal memory (p = 0.007). BD also presented worse performance than both MDD and HC, and MDD presented better performance than BD but worse than HC in quality of life and functionality. Multiple linear regression models were significative for education (p < 0.001) and age (p = 0.004) for BD and education (p < 0.001) for MDD.

CONCLUSION

In general, cognition is more affected in BD than MDD, which could be associated with functional and quality of life impairment.

Psychosocial remediation in depressive disorders: A systematic review

BACKGROUND

Social functioning impairment has been described in several psychiatric illness, including depressive disorders. It is associated with a deterioration in global functioning and quality of life, thus there is a growing interest in psychosocial functioning remediation interventions. This systematic review aims to review all psychotherapeutic, pharmacological and biological social functioning interventions in depressive disorders.

METHODS

A systematic search was conducted on PubMed, PsycINFO and Scopus from the first articles to 2019 following the PRISMA guidelines. 72 original papers were extracted from an initial number of 1827, based on the selected eligibility criteria.

RESULTS

A growing body of research was observed in the last 10 years, with most studies showing a low level of scientific evidence. The main diagnosis found was major depressive disorder and the principal social cognition domains assessed were emotional processing and attributional style. The type of intervention most found was the pharmacological one, followed by psychotherapeutic interventions classified as "non-specific. The efficacy of treatments showed an improvement in depressive symptoms and positive results for emotional processing and attributional style.

LIMITATIONS

Because there is a lack of well-controlled designs and really few interventions focusing on its remediation, and low homogeneity on the assessment of social aspects across, a comparison of results and the extraction of general conclusions is quite difficult.

CONCLUSIONS

Although a promising body of literature has been developed in recent years on the improvement of psychosocial functioning in patients with depressive disorders, more studies are needed to clarify relevant aspects in this area.

The neurocognitive profile of post-traumatic stress disorder (PTSD), major depressive disorder (MDD), and PTSD with comorbid MDD

OBJECTIVE

Neurocognitive dysfunction has been associated with post-traumatic stress disorder (PTSD) and major depressive disorder (MDD). However, although PTSD is often comorbid with MDD, there is little neurocognitive work to date on individuals who suffer from both PTSD and MDD. Here, we compared neurocognitive domains in individuals with PTSD, MDD, and comorbid PTSD and MDD with those of healthy controls.

METHODS

Participants comprised of mothers enrolled in the Drakenstein Child Health Study, a study exploring child health determinants in the Drakenstein district, Western Cape. N = 175 mothers (between 18 and 50 years) were recruited and divided into 4 groups: PTSD, MDD, PTSD with MDD, and healthy controls. Participants were assessed using the computerized NIH Toolbox, and paper and pencil neurocognitive tests. Domains assessed included executive function, memory, attention, learning, and processing speed.

RESULTS

Distinct patterns of neurocognitive dysfunction were observed in this sample. PTSD was associated with more intrusion errors and MDD was associated with delayed recall impairment, relative to healthy controls. PTSD with comorbid MDD was associated with processing speed impairments, relative to healthy controls, and monodiagnostic groups. No group differences were observed on measures of attention and executive function.

CONCLUSION

Distinct patterns of neurocognitive dysfunction were associated with diagnoses of MDD and PTSD. Greater anticipated dysfunction and impairment in comorbid PTSD and MDD was not observed, however. Further work is needed to replicate and extend these findings.

Using prefrontal and midline right frontal EEG-derived theta cordance and depressive symptoms to predict the differential response or remission to antidepressant treatment in major depressive disorder

There is a growing need for optimizing treatment selection and response prediction in individuals with major depressive disorder (MDD). Prior investigations have shown that changes in electroencephalographic (EEG)-based measures precede symptom improvement and could serve as biomarkers of treatment outcome. One such method is cordance, a computation of regional brain activity based on a combination of absolute and relative resting EEG activity. Specifically, early reduction in prefrontal (PF) and midline right frontal (MRF) theta (4-8Hz) cordance has been shown to predict response to various antidepressants, though replication is required. Thus, this study examined early changes (baseline to week 1) in PF and MRF cordance in 47 MDD patients undergoing antidepressant treatment. Early changes in cordance and in Montgomery Åsberg Depression Rating Scale (MADRS) scores were assessed alone, and in combination, to predict eventual (by week 12) treatment response and remission. Models combining early changes in theta cordance (PF and MRF) and depressive symptoms were most predictive of response to treatment at week 12; remission models (cordance, MADRS, and their combination) were weaker, though provided modest prediction values. These results suggest that antidepressant response may be optimally predicted by combining both EEG and symptom-based measures after one week of treatment.

Interactive effects of gender and sexual orientation on cortical thickness, surface area and gray matter volume: a structural brain MRI study

Background

Testosterone is thought to play a crucial role in sexual differentiation of the brain, and sexual orientation is programmed into our brain structures even when we are still fetuses. Although gender and sexual orientation differences have been shown respectively in many brain structures, the mechanism underlying the sexual differentiation of the brain is still unknown. The study is to investigate the interactive effects of gender and sexual orientation on cerebral structures in homosexual and heterosexual people.

Methods

Sexual orientation was evaluated by the Kinsey scale. We collected structural magnetic resonance image (MRI) data of local cortical thickness, surface area, and gray matter volume in all the subjects (29 homosexual and 29 heterosexual men, 17 homosexual and 17 heterosexual women). Statistical maps were generated using a general linear model (GLM) using FreeSurfer's Query, Design, Estimate, Contrast (QDEC) interface. We had sexual orientation and gender as 2 discrete factors with 2 levels, allowing for the generation of the interaction between sexual orientation and gender: homosexual women and heterosexual men versus heterosexual women and homosexual men. Coordinates were in Talairach space. All the cluster sizes were calculated with a P value of 0.01.

Results

Results revealed interactions concerning the area and gray matter volume between the factors of sexual orientation and gender. Regarding the thickness, an interaction was not found in any regions of the clusters. Regarding the area, an interaction was found in region of left middle temporal lobe, inferior temporal lobe, lateral occipital lobe, fusiform [(-58.1, -38.6, -14.7), maximum vertex-wise (MV) log₁₀(P) =3.30, cluster size (CS) =1,286.90 mm²], and left rostral middle frontal lobe, pars opercularis, caudal middle frontal lobe [(-37.3, 23.6, 24.8), MV log₁₀(P) =2.92, CS =1,194.40 mm²]. Regarding the gray matter volume, an interaction was found in the region of the left pars opercularis (inferior frontal gyrus) [(-42.9, 6.3, 18.5), MV log₁₀(P) =1.31, CS =526.79 mm²].

Conclusions

The present study extends our understandings of how structural features differ in homosexual men, heterosexual men, homosexual women, and heterosexual women. Furthermore, it highlights the interactions between sexual orientation and gender in the left inferior frontal gyrus, bilateral temporal lobe, and the right rostral anterior cingulate cortex, which are suggested to play a critical role in the sexual differentiation of the human brain.

Self-reported social impairments predict depressive disorder in adults with autism spectrum disorder

In adults with autism spectrum disorder, co-occurring psychiatric conditions are prevalent, and depression is one of the most common co-occurring disorders. This study examined the relationship between depression and cognitive ability, autism symptom severity, and self-reported social impairments in autism spectrum disorder. A total of 33 adults with autism spectrum disorder and 28 adults with typical development completed a standardized psychiatric interview, cognitive test, measure of clinician-rated autism symptom severity, and self-report of social impairments. Nine participants with autism spectrum disorder (27%) met the criteria for a depressive disorder (autism spectrum disorder + depressive disorder). Relatively more females with autism spectrum disorder had a co-occurring depressive disorder. The typical development group had a higher intelligence quotient than the autism spectrum disorder group, but the autism spectrum disorder + depressive disorder group did not differ from the typical development or autism spectrum disorder group. While the autism spectrum disorder + depressive disorder group had lower clinician-rated autism symptom severity than the autism spectrum disorder group, the autism spectrum disorder + depressive disorder group reported more social impairments than the autism spectrum disorder group. Self-reported social impairments predicted depression in adults with autism spectrum disorder when accounting for symptom severity and cognitive ability. These findings suggest that more self-perceived social impairments are related to depressive disorders in autism spectrum disorder, and may help clinicians identify individuals who are vulnerable in developing a co-occurring depressive disorder. Future directions include follow-up studies with larger cohorts and longitudinal designs to support inferences regarding directionality of these relationships.

The association of cognitive deficits with mental and physical Quality of Life in Major Depressive Disorder

BACKGROUND

Patients with Major Depressive Disorder experience significantly reduced subjective Quality of Life (QOL), including impaired social and emotional functioning and greater fatigue and physical pain. Mounting evidence suggests that cognitive dysfunction (e.g., deficits in memory, executive function) contributes independently to the onset of reduced QOL, however the domain-specific nature of this relationship has not been investigated. The present study examined the relationship between specific cognitive domains (e.g., attention, spatial cognition) and specific deficits in mental and physical QOL in subjects with lifetime MDD, as well as acutely depressed, remitted and healthy participants.

METHODS

Data were obtained (N = 387) from the Cognitive Function and Mood Study (COFAMS), a cross-sectional study of emotional, functional and cognitive status in individuals with mood disorders. Participants' (acutely depressed n = 93, remitted n = 170, and healthy control n = 124) QOL was assessed with the 36-Item Short Form Health Survey (SF-36) and cognitive functioning was evaluated with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Colorado Assessment Tests (CATs) and the Psychology Experiment Building Language (PEBL).

RESULTS

Analyses revealed that poor immediate and delayed memory were associated with reduced mental QOL in individuals with lifetime MDD, acutely depressed, and healthy controls. In contrast, cognitive functioning was not associated with mental QOL in remitted patients. No cognitive domains were significantly related to physical QOL in any participant group.

CONCLUSIONS

The result suggests that deficits in immediate and delayed memory may contribute to reduced mental QOL in acute MDD, whereas cognition does not appear to play a role in physical QOL. Memory should be considered important cognitive treatment targets for MDD patients suffering specifically from reduced mental QOL.

Intrinsic Functional Brain Connectivity Predicts Onset of Major Depression Disorder in Adolescence: A Pilot Study

Children with familial risk for major depressive disorder (MDD) have elevated risk for developing depression as adolescents. Here, we investigated longitudinally whether resting-state functional connectivity (RSFC) could predict the onset of MDD. In this pilot study, we followed a group of never-depressed children with familial risk for MDD and a group of age-matched controls without familial risk who had undergone an MRI study at 8-14 years of age. Participants were reassessed 3-4 years later with diagnostic interviews. We first investigated group differences in RSFC from regions in the emotion regulation, cognitive control, and default mode networks in the children who later developed MDD (converted), the children who did not develop MDD (nonconverted), and the control group. We then built a prediction model based on baseline RSFC that was independent of the group differences to classify the individuals who later developed MDD. Compared with the nonconverted group, the converted group exhibited hypoconnectivity between subgenual anterior cingulate cortex (sgACC) and inferior parietal lobule (IPL) and between left and right dorsolateral prefrontal cortices. The nonconverted group exhibited higher sgACC-IPL connectivity than did both the converted and control groups, suggesting a possible resilience factor to MDD. Classification between converted and nonconverted individuals based on baseline RSFC yielded high predictive accuracy with high sensitivity and specificity that was superior to classification based on baseline clinical rating scales. Intrinsic brain connectivity measured in healthy children with familial risk for depression has the potential to predict MDD onset, and it can be a useful neuromarker in early identification of children for preventive treatment.

Comparison of cognitive performance in bipolar disorder, major depressive disorder, unaffected first-degree relatives, and healthy controls

AIM

The extent and specifics regarding cognitive dysfunction in patients with bipolar disorder (BD) or major depressive disorder (MDD) and their unaffected first-degree relatives (FDR) have not been addressed in any single study. The present study compared the cognitive function of patients with BD or MDD, their FDR, and healthy control (HC) individuals.

METHODS

The study population comprised adults (aged 18-55 years) with BD, adults with MDD, FDR (children or siblings of patients with BD or MDD), and HC (n = 105, 109, 85, and 95, respectively). The Repeatable Battery for the Assessment of Neuropsychological Status was used to assess neurocognitive functions, with five domains and 12 tests. A Wechsler Adult Intelligence Scale brief form was applied to evaluate IQ. Status of mood was assessed using the Young Mania Rating Scale and the Hamilton Depression Scale.

RESULTS

The mixed model indicated significant variation among the four groups in cognitive function. Cognitive impairments, compared to HC, progressively greater from least to most were found in: FDR, MDD, and BD (F = 32.74, P < 0.001). Years of education correlated with cognitive performance (F = 17.04, P < 0.001), as did IQ (F = 240.63, P < 0.001). The total score for the Hamilton Rating Scale for Depression negatively correlated with cognitive function (F = 5.78, P = 0.017).

CONCLUSION

Among the study groups, patients with BD had the most severe deficits, followed by MDD patients and FDR. Cognitive deficits could not be associated with a specific psychiatric disorder, but differences in degree were noted.

The Direct and Indirect Relationship Between Social Cognition and Psychosocial Dysfunction in Major Depressive Disorder

Background: Recent evidence suggests that depressed patients experience social cognitive deficits (e.g., poor affect recognition). However, very little is known regarding the contribution of social cognitive deficits to psychosocial dysfunction (e.g., occupational functioning). In particular, the mechanistic roles of depression severity and cognitive deficits (e.g., memory) in this domain have not been explored. The current study evaluated the extent to which mood symptoms and cognitive deficits provide a mechanistic explanation for the relationship between social cognitive and psychosocial deficits in major depressive disorder (MDD). Methods: Data were obtained from 111 participants with MDD (75 Female, mean age = 35, 84% Caucasian, 12% Asian, 4% Other) in the Cognitive Function and Mood Study (CoFaM-S), a cross-sectional study of mood, social cognition, cognition, and psychosocial functioning in mood disorders. Social cognitive abilities were assessed using the Social Perception subtest of the Wechsler Adult Intelligence Scale, and psychosocial dysfunction was clinically evaluated with the Functioning Assessment Short Test (FAST). Results: Cognitive deficits and mood symptoms did not significantly mediate relationships between social cognitive ability and psychosocial dysfunction. The exception was executive function, which mediated an indirect relationship between meaning interpretation (i.e., theory of mind) and self-perceived cognitive dysfunction. Conclusion: The results suggest that the relationship between social cognitive deficits and psychosocial dysfunction is not mechanistically explained by mood symptoms or nonsocial cognition. Development of treatment strategies targeting social cognitive deficits in patients with MDD is warranted.

The clinical relationship between cognitive impairment and psychosocial functioning in major depressive disorder: A systematic review

Cognitive deficits are frequently observed in major depressive disorder (MDD), as well as impaired long-term psychosocial functioning. However, the relationship between cognitive deficits and psychosocial functioning in MDD is under-investigated. We aim to systematically review the literature on the relationship between specific cognitive impairments and psychosocial functioning in MDD. We systematically reviewed English-language literature in PubMed, PsychINFO, Scopus and Web of Science using search terms related to psychosocial functioning. Additional studies were identified by searching reference lists. Following our inclusion/exclusion criteria, 28 studies were reviewed. Inclusion criteria included age (> 18), MDD diagnosed by standard tools (e.g., DSM-IV), use of cognitive and psychosocial assessments. Cross-sectional studies indicated that cognitive deficits in domains of executive functioning, attention, memory, and global cognition are associated with psychosocial dysfunction in domains of as quality of life, and social, occupational, and global functioning. The cognition-functioning relationship was also observed in longitudinal studies, showing that only specific cognitive domains affected psychosocial outcomes over the long-term course of illness. Older age and greater MDD symptom severity appear to enhance cognition-psychosocial dysfunction relationship, however little is known regarding the role of a number of other clinical factors (e.g., psychosis, illness duration).

The role of cognitive impairment in psychosocial functioning in remitted depression

BACKGROUND

Cognitive dysfunction is a prevalent and disabling symptom of Major Depressive Disorder (MDD), and is often retained in the remitted stage of illness. Emerging evidence suggests that cognitive impairment may be associated with dysfunction in a number of psychosocial domains (e.g., workplace productivity, social relationships). The current study explored the relationship between cognition and psychosocial functioning in remitted MDD and in healthy controls.

METHODS

Data were obtained from 182 participants of the Cognitive Function and Mood Study (CoFaM-S), a cross-sectional study of cognition, mood, and social cognition in mood disorders. Participants' (Remitted MDD n = 72, Healthy n = 110) cognition was assessed with a battery of cognitive tests including the Repeatable Battery for the Assessment of Neuropsychological Function (RBANS) and other standard measures of cognition (e.g., The Tower of London task). Psychosocial functioning was clinically evaluated with the Functioning Assessment Short Test (FAST).

RESULTS

The results indicated that executive functioning was the strongest independent predictor of functioning in remitted MDD patients, whereas various cognitive domains predicted psychosocial functioning in healthy individuals.

LIMITATIONS

Psychosocial functioning was measured with a clinical interview, and was therefore reliant on clinicians' judgement of impairment, as opposed to more objective measures of functioning.

CONCLUSIONS

These findings suggest that executive cognition plays an important role in functional recovery in remitted depression, and may be a crucial target in adjunctive treatment.

The effects of vortioxetine on cognitive performance in working patients with major depressive disorder: A short-term, randomized, double-blind, exploratory study

BACKGROUND

Major Depressive Disorder (MDD) is a complex disease characterized by emotional, physical and cognitive symptoms. We explored the efficacy of vortioxetine versus placebo on outcomes of cognition, functioning and mood symptoms in working patients with depression, using paroxetine as an active reference.

METHODS

Gainfully employed patients (18-65 years, N = 152) with MDD were randomized 1:1:1 to 8 weeks' double-blind, parallel treatment either with vortioxetine (10mg/day) or paroxetine (20mg/day), or with placebo. The primary efficacy measure was the Digit Symbol Substitution Test (DSST), analyzed using a mixed model for repeated measurements, and the key secondary efficacy measure was the University of San Diego Performance-based Skills Assessment - Brief (UPSA-B), analyzed using analysis of covariance (last observation carried forward).

RESULTS

At week 8, DSST and UPSA-B performance had improved relative to baseline in all treatment groups, with no statistically significant differences between treatment groups. While improvements in mood were comparable for vortioxetine and paroxetine, numerical improvements in cognitive performance (DSST) were larger with vortioxetine. Vortioxetine significantly improved overall cognitive performance and clinician-rated functioning relative to placebo. The majority of adverse events were mild or moderate, with nausea being the most common adverse event for vortioxetine.

LIMITATIONS

Small sample sizes implied limited statistical power.

CONCLUSION

This explorative study showed no significant differences versus placebo in DSST or UPSA-B performance at week 8. However, secondary results support vortioxetine as an effective and well-tolerated antidepressant, supporting an added benefit for cognition and functioning, which could have particular therapeutic relevance for the working patient population.

Network Mechanisms of Clinical Response to Transcranial Magnetic Stimulation in Posttraumatic Stress Disorder and Major Depressive Disorder

BACKGROUND

Repetitive transcranial magnetic stimulation (TMS) therapy can modulate pathological neural network functional connectivity in major depressive disorder (MDD). Posttraumatic stress disorder is often comorbid with MDD, and symptoms of both disorders can be alleviated with TMS therapy. This is the first study to evaluate TMS-associated changes in connectivity in patients with comorbid posttraumatic stress disorder and MDD.

METHODS

Resting-state functional connectivity magnetic resonance imaging was acquired before and after TMS therapy in 33 adult outpatients in a prospective open trial. TMS at 5 Hz was delivered, in up to 40 daily sessions, to the left dorsolateral prefrontal cortex. Analyses used a priori seeds relevant to TMS, posttraumatic stress disorder, or MDD (subgenual anterior cingulate cortex [sgACC], left dorsolateral prefrontal cortex, hippocampus, and basolateral amygdala) to identify imaging predictors of response and to evaluate clinically relevant changes in connectivity after TMS, followed by leave-one-out cross-validation. Imaging results were explored using data-driven multivoxel pattern activation.

RESULTS

More negative pretreatment connectivity between the sgACC and the default mode network predicted clinical improvement, as did more positive amygdala-to-ventromedial prefrontal cortex connectivity. After TMS, symptom reduction was associated with reduced connectivity between the sgACC and the default mode network, left dorsolateral prefrontal cortex, and insula, and reduced connectivity between the hippocampus and the salience network. Multivoxel pattern activation confirmed seed-based predictors and correlates of treatment outcomes.

CONCLUSIONS

These results highlight the central role of the sgACC, default mode network, and salience network as predictors of TMS response and suggest their involvement in mechanisms of action. Furthermore, this work indicates that there may be network-based biomarkers of clinical response relevant to these commonly comorbid disorders.

IDO chronic immune activation and tryptophan metabolic pathway: A potential pathophysiological link between depression and obesity

Obesity and depression are among the most pressing health problems in the contemporary world. Obesity and depression share a bidirectional relationship, whereby each condition increases the risk of the other. By inference, shared pathways may underpin the comorbidity between obesity and depression. Activation of cell-mediated immunity (CMI) is a key factor in the pathophysiology of depression. CMI cytokines, including IFN-γ, TNFα and IL-1β, induce the catabolism of tryptophan (TRY) by stimulating indoleamine 2,3-dioxygenase (IDO) resulting in the synthesis of kynurenine (KYN) and other tryptophan catabolites (TRYCATs). In the CNS, TRYCATs have been related to oxidative damage, inflammation, mitochondrial dysfunction, cytotoxicity, excitotoxicity, neurotoxicity and lowered neuroplasticity. The pathophysiology of obesity is also associated with a state of aberrant inflammation that activates aryl hydrocarbon receptor (AHR), a pathway involved in the detection of intracellular or environmental changes as well as with increases in the production of TRYCATs, being KYN an agonists of AHR. Both AHR and TRYCATS are involved in obesity and related metabolic disorders. These changes in the TRYCAT pathway may contribute to the onset of neuropsychiatric symptoms in obesity. This paper reviews the role of immune activation, IDO stimulation and increased TRYCAT production in the pathophysiology of depression and obesity. Here we suggest that increased synthesis of detrimental TRYCATs is implicated in comorbid obesity and depression and is a new drug target to treat both diseases.

Prefrontal activation during a working memory task differs between patients with unipolar and bipolar depression: A preliminary exploratory study

BACKGROUND

To identify bipolar disorder during the initial stages of a depressive episode has always been a great clinical challenge. Patterns of functional brain activity may underlie the differences in the neural mechanisms of bipolar depression (BD) and unipolar depression (UD). This study aimed to investigate the differences in neural activity between BD and UD patients during executive task.

METHODS

We performed a 52-channel near-infrared spectroscopy (NIRS) scan in 39 patients with BD, 35 patients with UD, and 36 healthy controls (HCs). The relative concentration changes in oxygenated hemoglobin ([oxy-Hb]) and deoxygenated hemoglobin ([deoxy-Hb]) during a 1-back working memory task were measured for each channel. Clinical characteristics including current mood were evaluated within one week prior to NIRS examination.

RESULTS

Compared to HCs, BD (CH34: Z = -2.354, P = 0.019) and UD patients (CH18: Z = -2.358, P = 0.018; CH30: Z = -2.174, P = 0.030; CH34: Z = -1.990, P = 0.047) showed reduced activation of [oxy-Hb] in the inferior prefrontal region. Compared to patients with UD, patients with BD showed less decreased [oxy-Hb] changes in the left frontopolar cortex (FPC) (CH18: Z = -2.366, P = 0.018), left pars opercularis and pars triangularis (POPE/PTRI) regions (Broca's area) (CH30: Z = -2.333, P = 0.020). No correlation existed between clinical characteristics and NIRS measurements.

LIMITATIONS

The effect of medication could not be excluded, and behavioral data was not systematically collected.

CONCLUSION

The results from this preliminary exploratory study suggest distinct prefrontal activation patterns underlie BD and UD, especially in the left frontopolar region and Broca's area. The NIRS-based prefrontal activation measurement may serve as a potential marker to aid in differentiating bipolar from unipolar depression.

Leveraging Machine Learning Approaches for Predicting Antidepressant Treatment Response Using Electroencephalography (EEG) and Clinical Data

Background: Individuals with major depressive disorder (MDD) vary in their response to antidepressants. However, identifying objective biomarkers, prior to or early in the course of treatment that can predict antidepressant efficacy, remains a challenge. Methods: Individuals with MDD participated in a 12-week antidepressant pharmacotherapy trial. Electroencephalographic (EEG) data was collected before and 1 week post-treatment initiation in 51 patients. Response status at week 12 was established with the Montgomery-Asberg Depression Scale (MADRS), with a ≥50% decrease characterizing responders (N = 27/24 responders/non-responders). We used a machine learning (ML)-approach for predicting response status. We focused on Random Forests, though other ML methods were compared. First, we used a tree-based estimator to select a relatively small number of significant features from: (a) demographic/clinical data (age, sex, individual item/total MADRS scores at baseline, week 1, change scores); (b) scalp-level EEG power; (c) source-localized current density (via exact low-resolution electromagnetic tomography [eLORETA] software). Second, we applied kernel principal component analysis to reduce and map important features. Third, a set of ML models were constructed to classify response outcome based on mapped features. For each dataset, predictive features were extracted, followed by a model of all predictive features, and finally by a model of the most predictive features. Results: Fifty eLORETA features were predictive of response (across bands, both time-points); alpha₁/theta eLORETA features showed the highest predictive value. Eighty-eight scalp EEG features were predictive of response (across bands, both time-points), with theta/alpha₂ being most predictive. Clinical/demographic data consisted of 31 features, with the most important being week 1 "concentration difficulty" scores. When all features were included into one model, its predictive utility was high (88% accuracy). When the most important features were extracted in the final model, 12 predictive features emerged (78% accuracy), including baseline scalp-EEG frontopolar theta, parietal alpha₂ and frontopolar alpha₁. Conclusions: These findings suggest that ML models of pre- and early treatment-emergent EEG profiles and clinical features can serve as tools for predicting antidepressant response. While this must be replicated using large independent samples, it lays the groundwork for research on personalized, "biomarker"-based treatment approaches.

Executive Function and Spatial Cognition Mediate Psychosocial Dysfunction in Major Depressive Disorder

Background: Cognitive and psychosocial dysfunction are prevalent and disabling features of Major Depressive Disorder (MDD). Emerging evidence suggests that poor cognitive functioning mediates the negative effect of MDD on psychosocial function. However, there is a lack of research examining the domain-specific nature of this relationship. The current study evaluated whether the relationship between MDD and specific psychosocial subdomains (e.g., autonomy, occupational functioning) was mediated by domain-specific cognitive deficits. Methods: Data from 155 participants was obtained from the Cognitive Function and Mood Study (CoFaMS), a cross-sectional analysis of mood, cognition, social cognition, and functioning in individuals with MDD. Cognitive functioning was assessed (Current MDD n = 45, Healthy n = 110), with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Colorado Assessment Tests (CATs), and the Psychology Experiment Building Language (PEBL). Psychosocial functioning was clinically evaluated with the Functioning Assessment Short Test (FAST). Results: The results indicated that spatial cognition and executive functioning partially mediated the negative effect of MDD on overall psychosocial functioning, autonomy, and subjective cognition. In contrast, spatial and executive domains showed divergent mediation patterns on interpersonal relationships and leisure time. Conclusions: The findings suggest that executive and spatial cognition play an important role in the pathology of overall psychosocial functioning, and specific functional issues in MDD. Treatments targeting psychosocial recovery in MDD may be improved by emphasizing executive and spatial cognitive remediation.

Executive Subdomains Are Differentially Associated With Psychosocial Outcomes in Major Depressive Disorder

Background: Deficits in executive functioning are frequently associated with poor psychosocial outcomes in Major Depressive Disorder (MDD). However, there is a poor understanding of the domain-specific relationships between executive subdomains (e.g., forward planning, decision making) and specific psychosocial issues (e.g., occupational functioning, social relationships). The current study explored these relationships across currently depressed and remitted MDD patients, as well as a healthy control group. Methods: Data from 142 participants were obtained from the Cognitive Functioning and Mood Study (CoFaM-S), a cross sectional study of mood, cognition, and psychosocial functioning in mood disorders. Participants' [current depression n = 31, remitted depression n = 52, healthy controls (HC) n = 59] executive functioning was evaluated with well-established tests of executive subdomains (i.e., Tower of London, card sorting, Stroop task). The Functioning Assessment Short Test (FAST) was employed to clinically evaluate psychosocial dysfunction. Results: The results indicated that forward planning was most strongly associated with psychosocial issues in the current depression group as compared to HCs, while cognitive updating was primary in the remitted group vs. HC. Conclusions: These findings suggest that executive subdomains are deferentially associated with psychosocial issues across different stages of depressive illness, and that forward planning and cognitive updating should be considered in adjunctive cognitive treatment.

Short- and Long-term Cognitive Outcomes in Patients With Major Depression Treated With Electroconvulsive Therapy

OBJECTIVES

The risk of cognitive impairment is a concern for patients with major depressive disorder receiving electroconvulsive therapy (ECT). Here, we evaluate the acute, short-term and long-term effects of ECT on tests of processing speed, executive function, memory, and attention.

METHODS

Forty-four patients with major depressive disorder receiving ECT (61% right unilateral, 39% mixed right unilateral-bitemporal, left unilateral, and/or bitemporal lead placement) underwent a cognitive battery prior to ECT (T1), after 2 sessions (T2), and at the end of the index (T3). Thirty-two patients returned for a 6-month follow-up (T4). Thirty-three control subjects were assessed at 2 times approximately 4 weeks apart (C1 and C2).

RESULTS

At baseline, patients showed deficits in processing speed, executive function, and memory compared with control subjects. Including depression severity and lead placement covariates, linear mixed-model analysis showed significant improvement in only processing speed between T1 and T3 and between T1 and T4 in patients. An acute decline in attention and verbal memory was observed at T2, but performance returned to baseline levels at T3. Longitudinal cognitive outcomes did not differ in patients defined as ECT responders/nonresponders.

LIMITATIONS

Episodic memory was not measured, and medications were not controlled between T3 and T4. Control subjects also showed improvements in processing speed, suggesting practice effects for some measures.

CONCLUSIONS

In this naturalistic ECT treatment study, results show that the initiation of ECT may transiently affect memory and executive function, but cognition is largely unaffected during and after ECT. Whereas some functions might improve, others will at least remain stable up to 6 months following the ECT index.

Modafinil Improves Episodic Memory and Working Memory Cognition in Patients With Remitted Depression: A Double-Blind, Randomized, Placebo-Controlled Study

Background

Cognitive dysfunction is a core feature of depression and tends to persist even after mood symptoms recover, leading to detrimental effects on clinical and functional outcomes. However, most currently available treatments have not typically addressed cognition. Modafinil has been shown to have beneficial effects on cognitive function and therefore has the potential to improve cognition in depression. The objective of this double-blind, placebo-controlled study was to investigate the effects of modafinil on cognitive functions in patients with remitted depression.

Methods

In total, 60 patients with remitted depression participated in the study. Cognitive functions were evaluated with tests of working memory, planning, attention, and episodic memory from the Cambridge Neuropsychological Test Automated Battery at the baseline session and after treatment. A double-blind, randomized, placebo-controlled, parallel groups design was used to assess the effects of single-dose (200 mg) modafinil (n = 30) or placebo (n = 30) on cognition and fatigue. The main outcome measures were neurocognitive test scores from the Cambridge Neuropsychological Test Automated Battery. Visual analogue scales for subjective feelings and fatigue were used as secondary measures.

Results

The modafinil group had significantly better performance on tests of episodic memory (p = .01, η_p² = .10) and working memory (p = .04, η_p² = .06). Modafinil did not improve planning or sustained attention.

Conclusions

This study suggested that modafinil (200 mg) could improve episodic memory and working memory performance in patients with remitted depression. Modafinil may have potential as a therapeutic agent to help remitted depressed patients with persistent cognitive difficulties.

Neurocognitive Predictors of Response in Treatment Resistant Depression to Subcallosal Cingulate Gyrus Deep Brain Stimulation

Background: Deep brain stimulation (DBS) is a neurosurgical intervention with demonstrated effectiveness for treatment resistant depression (TRD), but longitudinal studies on the stability of cognitive parameters following treatment are limited. The objectives of this study are to (i) identify baseline cognitive predictors of treatment response to subcallosal cingulate gyrus (SCG) DBS for unipolar TRD and (ii) compare neurocognitive performance prior to and 12 months after DBS implantation.

Methods: Twenty unipolar TRD patients received SCG DBS for 12 months. A standardized neuropsychological battery was used to assess a range of neurocognitive abilities at baseline and after 12 months. Severity of depression was evaluated using the 17 item Hamilton Rating Scale for Depression.

Results: Finger Tap-Dominant Hand Test and total number of errors made on the Wisconsin Card Sorting Test predicted classification of patients as treatment responders or non-responders, and were independent of improvement in mood. Change in verbal fluency was the only neuropsychological test that correlated with change in mood from baseline to the follow up period. None of the neuropsychological measures displayed deterioration in cognitive functioning from baseline to repeat testing at 12 months.

Limitations: This was an open label study with a small sample size which limits predictive analysis. Practice effects of the neuropsychological testing could explain the improvement from baseline to follow up on some tasks. Replication using a larger sample of subjects who received neuropsychological testing before and at least 12 months after DBS surgery is required.

Conclusion: These preliminary results (i) suggest that psychomotor speed may be a useful baseline predictor of response to SCG DBS treatment and (ii) support previous suggestions that SCG DBS has no deleterious effects on cognition.

Psychosocial Dysfunction in Major Depressive Disorder-Rationale, Design, and Characteristics of the Cognitive and Emotional Recovery Training Program for Depression (CERT-D)

INTRODUCTION

Psychosocial dysfunction is associated with poor longitudinal course of depression and is not sufficiently addressed by existing pharmaceutical or psychological treatments. The aim of the current study is to evaluate the efficacy of a novel intervention designed to improve psychosocial function in depressed individuals. Impaired cognition, emotion processing, and social cognition appear to underlie (i.e., cause) psychosocial dysfunction in depression. The current treatment will target functioning in these domains (i.e., cognition, emotion, social cognition) with repeated training tasks, following the rationale that therapeutic benefits will arise in psychosocial functioning. It is expected that personalizing treatment by participants' baseline functioning will enhance clinical efficacy, by comparison with standard treatment in which baseline functioning is not considered.

METHODS

The study is a randomized, controlled treatment (RCT), in which the efficacy of a personalized and standard intervention will be compared. Sixteen treatment sessions will be administered over an 8-week period. These treatments are designed to improve cognition, emotion processing and social cognition. Assessments of psychosocial functioning, as well as a number of secondary outcomes, will occur at baseline, 4 weeks (mid-RCT), 8 weeks (end of RCT), and in the observational period at baseline (week 9) and 3 and 6 months post-RCT. Recruitment will commence in July 2017, including subjects diagnosed with major depressive disorder according to DSM-IV-TR criteria.

DISCUSSION

This research will provide new insight into the roles of cognition, emotion processing, and social cognition in psychosocial dysfunction in depression. In addition, the relative clinical efficacy of personalized versus standard treatment approaches will be assessed.

ETHICS AND DISSEMINATION

This study has been approved by the human research ethics committees of the Royal Adelaide Hospital and the University of Adelaide (ethics code: R20170611). The study has been registered with the Australia and New Zealand Clinical Trials Registry Registration number: ACTRN12617000899347, web link: http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12617000899347p. The results of the current study will be published in academic journals following completion of recruitment in 2019. Data will be owned and retained by the University of Adelaide, with access restricted to the research team responsible for the study.

Cognitive dysfunction in major depression and bipolar disorder: Assessment and treatment options

Cognitive dysfunction is a recognized feature of mood disorders, including major depressive disorder (MDD) and bipolar disorder (BD). Cognitive impairment is associated with poor overall functional outcome and is therefore an important feature of illness to optimize for patients' occupational and academic outcomes. While generally people with BD appear to have a greater degree of cognitive impairment than those with MDD, direct comparisons of both patient groups within a single study are lacking. There are a number of methods for the assessment of cognitive function, but few are currently used in clinical practice. Current symptoms, past course of illness, clinical features, such as the presence of psychosis and comorbid conditions, may all influence cognitive function in mood disorders. Despite the general lack of assessment of cognitive function in clinical practice, clinicians are increasingly targeting cognitive symptoms as part of comprehensive treatment strategies. Novel pharmacological agents may improve cognitive function, but most studies of standard mood stabilizers, such as lithium and the anticonvulsants, have focused on whether or not the medications impair cognition. Non-pharmacological strategies, such as cognitive remediation and exercise, are increasingly studied in patients with mood disorders. Despite the growing interest in strategies to manage cognitive function, there is a paucity of high-quality trials examining either pharmacological or non-pharmacological modes of intervention.

[Cognition - the core of major depressive disorder]

Cognitive deficits have been only recently recognized as a major phenotype determinant of major depressive disorder, although they are an integral part of the definition of the depressive state. Congruent evidence suggest that these cognitive deficits persist beyond the acute phase and may be identified at all ages. The aim of the current study was to review the main meta-analyses on cognition and depression, which encompasses a large range of cognitive domains. Therefore, we discuss the "cold" (attention, memory, executive functions) and "hot" (emotional bias) cognitive impairments in MDD, as well as those of social cognition domains (empathy, theory of mind). Several factors interfere with cognition in MDD such as clinical (melancholic, psychotic...) features, age, age of onset, illness severity, medication and comorbid condition. As still debated in the literature, the type of relationship between the severity of cognitive symptoms and functioning in depression is detailed, thus highlighting their predictive value of functional outcome, independently of the affective symptoms. A better identification of the cognitive deficits in MDD and a monitoring of the effects of different treatments require appropriate instruments, which may be developed by taking advantage of the increasing success of computing tools. Overall, current data suggest a core role for different cognitive deficits in MDD, therefore opening new perspectives for optimizing the treatment of depression.

Impact of psychotic symptoms on cognitive functioning in child and adolescent psychiatric inpatients with severe mood disorders

Despite established differences in cognitive functioning of adults with mood disorder-related psychosis and those with non-affective psychotic disorders, there is limited evidence of the impact of psychotic symptoms on the cognitive functioning of children and adolescents with mood disorders. This study investigates IQ, working memory, and processing speed scores in 80 child and adolescent inpatients discharged from an intermediate care state psychiatric hospital, using a retrospective chart review. Associations between diagnosis based on DSM-IV criteria (7 with Major Depression- MDD; 43 with Bipolar Disorders-BD, and 30 with Mood Disorders Not Otherwise Specified-NOS), presence of current psychotic features, and cognitive functioning (WISC-IV IQ, Coding, Symbol Search, and Digit Span) were investigated using Multivariate Analyses of Variance. No differences were found in cognitive functioning between patients with MDD and BD, or between those with severe Mood Disorders (MDD or BD) and those with NOS, when controlling for age, gender, and presence of psychotic features. However, patients with severe mood disorders and psychotic features showed lower IQs and greater working memory deficits than those without psychotic features or NOS. Results are discussed in terms of treatment planning for children and adolescents at risk for developing psychotic symptoms and severe mood disorders.

Clinical, Functional, and Biological Correlates of Cognitive Dimensions in Major Depressive Disorder - Rationale, Design, and Characteristics of the Cognitive Function and Mood Study (CoFaM-Study)

Cross-sectional and longitudinal studies exploring clinical, functional, and biological correlates of major depressive disorder are frequent. In this type of research, depression is most commonly defined as a categorical diagnosis based on studies using diagnostic instruments. Given the phenotypic and biological heterogeneity of depression, we chose to focus the phenotypic assessments on three cognitive dimensions of depression including (a) cognitive performance, (b) emotion processing, and (c) social cognitive functioning. Hence, the overall aim of the study is to investigate the long-term clinical course of these cognitive dimensions in depression and its functional (psychosocial) correlates. We also aim to identify biological "genomic" correlates of these three cognitive dimensions of depression. To address the above overall aim, we created the Cognition and Mood Study (CoFaMS) with the key objective to investigate the clinical, functional, and biological correlates of cognitive dimensions of depression by employing a prospective study design and including a healthy control group. The study commenced in April 2015, including patients with a primary diagnosis of a major depressive episode of major depressive disorder or bipolar disorder according to DSM-IV-TR criteria. The assessments cover the three cognitive dimensions of depression (cognitive performance, emotion processing, and social cognition), cognitive function screening instrument, plus functional scales to assess general, work place, and psychosocial function, depression symptom scales, and clinical course of illness. Blood is collected for comprehensive genomic discovery analyses of biological correlates of cognitive dimensions of depression. The CoFaM-Study represents an innovative approach focusing on cognitive dimensions of depression and its functional and biological "genomic" correlates. The CoFaMS team welcomes collaborations with both national and international researchers.

Bipolar Disorder and Inflammation

The pathophysiology of bipolar disorder (BD) remains poorly understood. Current psychopharmacologic treatments are often poorly tolerated and carry high rates of treatment resistance. Mounting evidence has suggested that innate immune system dysfunction may play a role in the pathophysiology of BD. Elevated proinflammatory cytokine levels have been identified. The innate immune system is a novel therapeutic target in BD. Lithium has been shown to have antiinflammatory properties. Further research is needed to establish the role of antiinflammatory agents in the treatment of BD; however, evidence from several clinical trials indicates that antiinflammatory agents may be incorporated into clinical practice soon.

Cognitive Deficits as a Mediator of Poor Occupational Function in Remitted Major Depressive Disorder Patients

Cognitive deficits in major depressive disorder (MDD) patients have been described in numerous studies. However, few reports have aimed to describe cognitive deficits in the remitted state of MDD and the mediational effect of cognitive deficits on occupational outcome. The aim of the current review is to synthesize the literature on the mediating and moderating effects of specific domains of cognition on occupational impairment among people with remitted MDD. In addition, predictors of cognitive deficits found to be vocationally important will be examined. Upon examination of the extant literature, attention, executive function and verbal memory are areas of consistent impairment in remitted MDD patients. Cognitive domains shown to have considerable impact on vocational functioning include deficits in memory, attention, learning and executive function. Factors that adversely affect cognitive function related to occupational accommodation include higher age, late age at onset, residual depressive symptoms, history of melancholic/psychotic depression, and physical/psychiatric comorbidity, whereas higher levels of education showed a protective effect against cognitive deficit. Cognitive deficits are a principal mediator of occupational impairment in remitted MDD patients. Therapeutic interventions specifically targeting cognitive deficits in MDD are needed, even in the remitted state, to improve functional recovery, especially in patients who have a higher risk of cognitive deficit.

Executive function impairments in depression and bipolar disorder: association with functional impairment and quality of life

BACKGROUND

The neuropsychological correlates of major depressive (MDD) and bipolar disorder (BD), and their association with quality of life (QOL) and functioning, have not been sufficiently studied in the literature. The present study aimed to compare executive functions, attention, processing speed, QOL and disability between patients with BD type I, BD type II, MDD and healthy controls.

METHOD

205 participants (n=37 BDI, 81% female; n=35 BDII, 80% female; n=45 MDD, 69% female; n=89C, 46% female) aged between 18 and 67 years were administered an extensive neurocognitive battery consisting of widely used standardized measures such as the Trail Making Test, the Stroop Color-Word Test and a modified version of the Wisconsin Card Sorting Task. Z-scores were compared between groups by ANCOVA. The prevalence of impairments on each measure (Z-score<1.5) was compared between groups using chi-square tests. The associations between cognition, quality of life and functioning were evaluated through correlational analysis.

RESULTS

Patients with MDD showed poor selective and sustained attention, and exhibited impairments in timed tasks, suggesting low efficiency of executive processing. Patients with BDI displayed more widespread cognitive impairment than the remaining groups, and performed worse than subjects with MDD on measures of sustained attention and inhibitory control. Decision-making ability and attentional control were able to distinguish between patients with BDI and BDII. QOL and disability were most impaired in patients with BDI, and more closely associated with cognitive impairment than in the remaining groups.

LIMITATIONS

No control of pharmacological variables, clinical or demographic characteristics.

CONCLUSIONS

Our results provide important information regarding the nature and severity of the cognitive alterations associated with different mood disorders, and may contribute to the diagnosis, rehabilitation and treatment of these conditions.

Cognitive function in euthymic bipolar disorder (BP I) patients with a history of psychotic symptoms vs. schizophrenia

Patients with bipolar disorder show cognitive deficits including executive function, which appear to be related to social functioning and outcome. However, subgroups within the spectrum as well as psychopathological features, current mood state/euthymia and disease stage might be confounding factors. We analysed data tests from the Wechsler Intelligence Scale (WIE), verbal fluency (COWA) and trail making tests (TMT-A and TMT-B) obtained in a selected subgroup of currently bipolar I disorder patients, who were currently euthymic and had a history of psychotic symptoms, and compared them to patients with schizophrenia (in remission) and healthy controls, all matched for age, gender, and handedness. Schizophrenia patients showed more severe cognitive impairment, including digit symbol and arithmetic tests, as well as TMT-B (compared to healthy controls), but bipolar patients had stronger impairment on the letter number sequencing test, an indicator of working memory and processing speed. There were no group effects on most verbal fluency tasks (except impairment of schizophrenia patients on one subscale of category fluency). Within the limitations of the study design, our results suggest that even in subgroups of presumably more severely impaired bipolar patients, some cognitive dimensions might achieve remission, possibly related to considerable state effects at testing.

The prevalence, measurement, and treatment of the cognitive dimension/domain in major depressive disorder

Insufficient outcomes amongst adults with major depressive disorder (MDD) provide the impetus to identify and refine therapeutic targets that are most critical to outcome from patient, provider, and societal perspectives. Towards this aim, a pivotal shift towards the transnosological domain, cognition, is occurring in the study of MDD and other brain disorders. This paper aims to provide a framework for conceptualizing and prioritizing cognitive function amongst adults with MDD with a particular view to provide a conceptual framework for research and clinical priorities. We also summarize extant data pertaining to psychotropic effects, notably antidepressants, on the cognitive dimension/domain. This narrative review was based on articles identified through a PubMed/MEDLINE search of all English-language articles published between January 1966 and October 2014. The search words were major depressive disorder, depression, unipolar depression, cognition, cognitive dysfunction, cognitive deficit, and cognitive function. The search was supplemented with a manual review of relevant references. The selection of articles for inclusion in this review was based on overall methodological quality as well as on their pertinence to informing the framework described herein. Cognitive dysfunction in MDD is a discrete domain subserved by discrete yet overlapping substrates. There is a need to provide a glossary of terms commonly employed in the cognition literature for consensus as to the appropriate screening, measurement, and monitoring tools. The guiding principle of measurement-based care should include systematic assessment and measurement of cognition in subpopulations with MDD, as a tactic to improve outcome. Relatively few treatment strategies have demonstrated efficacy specifically for the cognitive domain in MDD. The antidepressant vortioxetine has replicated evidence of specific pro-cognitive effects in adults with MDD across multiple subdomains of cognitive function. Vortioxetine is a novel antidepressant that is hypothesized to act through a combination of direct effects on receptor activity and serotonin receptor inhibition, as well as other systems. Pro-cognitive effects for other US FDA-approved agents are suggested, but pseudospecificity has not been excluded as a possible explanation of their beneficial effects on cognitive function. A disparate assortment of other agents are currently under investigation for possible benefit in mitigating cognitive deficits and improving cognitive performance (e.g., intranasal insulin, erythropoietin, anti-inflammatory agents). Non-pharmacological approaches including, but not limited to, cognitive remediation (CR), aerobic exercise, and neuromodulation are promising.

Cognitive and Functional Impairment in Stroke Survivors with Basilar Artery Occlusive Disease

Background. Despite growing literature on posterior vascular disease, specific information about the cognitive and functional profiles of patients with basilar artery occlusion disease (BAOD) is scarce. The aims of this study were (1) to compare the cognitive statuses of BAOD survivors versus healthy controls and (2) to correlate the functional capacity outcomes with the cognitive profiles of BAOD patients. Methods. Comprehensive cognitive and functional assessments were carried out in 28 patients with BAOD and 27 age- and education level-matched healthy controls. Results. Compared to matched controls, patients presented impairments in selective, sustained, and set-shifting attention, processing speed, visuospatial skills, mental flexibility, and monitoring rules. There were significant deficits in verbal episodic memory (immediate and delayed recall) and visuospatial episodic memory (immediate and delayed recall and recognition). Functional capacity outcomes were significantly related to the cognitive test results. Seventy-five percent of patients had a Modified Rankin Scale score of 0 or 1. Conclusions. Our results indicate good functional outcomes in a selected group of BAOD survivors, despite the presence of subnormal performance on some cognitive tests, including tests of attention, executive function, and long-term memory.

Gender differences and disabilities of perceived depression in the workplace

BACKGROUND

Few studies have investigated gender difference and associated disability among workers. Comprehensive investigations concerning the occurrence and consequences of depression in workplace are scarce. The study aims to evaluate how workers perceive depression in workplace, as well as to examine depression-related disabilities by gender.

METHODS

This is a cross-sectional web-based survey of 1000 Brazilian workers recruited from Internet sources. Participants answered an online questionnaire about depressive symptoms and related consequences in the workplace.

RESULTS

Common symptoms attributable to depression were crying, loss of interest, and sadness. Almost one in five (18.9%) participants reported had ever been "labeled" by a health professional as suffering from depression. However, the majority of ever-depressed workers (73.5%) remained working. Performance-related impairments were reported by around 60% of depressed workers who continued working. Over half of them also complained about cognitive symptoms (concentration difficulties, indecisiveness, forgetfulness), with men reporting more cognitive dysfunctions than women. One in three workers had taken off work due to depression (mean 65.7 out-of-role days), with these periods being lengthier for men than women.

LIMITATIONS

Some depressive events might have occurred before working age, since the participants have self-reported the diagnosis of health professionals in past timeframe. The representativeness of recruited workers was reliant upon the availability of Internet service.

CONCLUSIONS

The findings suggest that identification and management of symptoms of depression should be set as a priority in worker׳s health care. General and gender-related strategies to handle depression in the workplace are recommended.

Audiovisual emotional processing and neurocognitive functioning in patients with depression

Alterations in the processing of emotional stimuli (e.g., facial expressions, prosody, music) have repeatedly been reported in patients with major depression. Such impairments may result from the likewise prevalent executive deficits in these patients. However, studies investigating this relationship are rare. Moreover, most studies to date have only assessed impairments in unimodal emotional processing, whereas in real life, emotions are primarily conveyed through more than just one sensory channel. The current study therefore aimed at investigating multi-modal emotional processing in patients with depression and to assess the relationship between emotional and neurocognitive impairments. Fourty one patients suffering from major depression and 41 never-depressed healthy controls participated in an audiovisual (faces-sounds) emotional integration paradigm as well as a neurocognitive test battery. Our results showed that depressed patients were specifically impaired in the processing of positive auditory stimuli as they rated faces significantly more fearful when presented with happy than with neutral sounds. Such an effect was absent in controls. Findings in emotional processing in patients did not correlate with Beck's depression inventory score. Furthermore, neurocognitive findings revealed significant group differences for two of the tests. The effects found in audiovisual emotional processing, however, did not correlate with performance in the neurocognitive tests. In summary, our results underline the diversity of impairments going along with depression and indicate that deficits found for unimodal emotional processing cannot trivially be generalized to deficits in a multi-modal setting. The mechanisms of impairments therefore might be far more complex than previously thought. Our findings furthermore contradict the assumption that emotional processing deficits in major depression are associated with impaired attention or inhibitory functioning.

The effect of bupropion XL and escitalopram on memory and functional outcomes in adults with major depressive disorder: results from a randomized controlled trial

Decrements in cognitive function are a common feature of Major Depressive Disorder (MDD), and whether distinct classes of antidepressants differentially affect memory in these individuals has not been sufficiently evaluated. In this study we sought to determine the effect of escitalopram and bupropion XL on memory and psychosocial function. Forty-one individuals (18-50 years) with MDD were enrolled in an 8-week, double-blind, double-dummy, randomized controlled comparative trial of bupropion XL and escitalopram. Thirty-six participants completed pre and post memory assessments. Verbal, non-verbal and working memory were evaluated with a comprehensive neuropsychological battery. Psychosocial function was assessed with the Sheehan Disability Scale and Endicott Work Productivity Scale. Escitalopram and bupropion XL significantly improved immediate as well as delayed verbal and nonverbal memory, global function (all p≤0.001), and work productivity (p=0.045), with no significant between-group differences. Improvement in immediate verbal memory exerted a direct influence on improvement in global function (p=0.006). Treatment with either escitalopram or bupropion XL was associated with improvement in memory and psychosocial function in adults with MDD.

Pharmacological and non-pharmacological interventions to improve cognitive dysfunction and functional ability in clinical depression--a systematic review

Cognitive dysfunction is of clinical significance and exerts longstanding implication on patients׳ function. Pharmacological and non-pharmacological treatments of cognitive dysfunction are emerging. This review evaluates pharmacological and non-pharmacological treatments of cognitive impairment primarily in the domains of memory, attention, processing speed and executive function in clinical depression. A total of 35 studies were retrieved from Pubmed, PsycInfo and Scopus after applying inclusion and exclusion criteria. Results show that various classes of antidepressants exert improving effects on cognitive function across several cognitive domains. Specifically, studies suggest that SSRIs, the SSRE tianeptine, the SNRI duloxetine, vortioxetine and other antidepressants such as bupropion and moclobemide may exert certain improving effects on cognitive function in depression, such as in learning and memory and executive function. Class-specific cognitive domains or specific dose-response relationships were not identified yet. The few non-pharmacological studies conducted employing cognitive orientated treatments and cognitive remediation therapy show promising results for the improvement of cognitive impairment in depression. However, several methodological constraints of studies limit generalizability of the results and caution the interpretation. Future direction should consider the development of a neuropsychological consensus cognitive battery to support the discovery, clinical assessment, comparison of studies and registration of new agents in clinical depression.