The neurocognitive profile of mood disorders - a review of the evidence and methodological issues

Cognitive predictors of response to interpersonal and social rhythm therapy in mood disorders

BACKGROUND

There has been increasing interest in examining the potential moderating effects that cognitive functioning has on treatment outcome in bipolar disorder (BD) and major depressive disorder (MDD). Therefore, the aim of this exploratory study was to examine the relationship between baseline cognitive function and treatment outcome in individuals with mood disorders who completed 12 months of interpersonal and social rhythm therapy (IPSRT), and were randomised to receive adjunctive cognitive remediation (CR) or no additional intervention.

METHODS

Fifty-eight patients with mood disorders (BD, n = 36, MDD, n = 22), who were randomised to IPSRT-CR or IPSRT, underwent cognitive testing at baseline and completed follow-up mood measures after 12 months. General linear modelling was used to examine the relationship between baseline cognitive function (both objective and subjective) and change in mood symptom burden, and functioning, from baseline to treatment-end.

RESULTS

Poorer baseline attention/executive function was associated with less change in mood symptom burden, particularly depressive symptoms, at treatment-end. Additionally, slower psychomotor speed at baseline was associated with less improvement in mania symptom burden. Subjective cognitive function at baseline was not related to change in mood symptom burden at treatment-end, and neither objective nor subjective cognitive function was associated with functional outcome.

LIMITATIONS

Due to the exploratory nature of the study, there was no correction for multiple comparisons.

CONCLUSION

Aspects of objective cognitive function were associated with treatment outcomes following psychotherapy. Further large-scale research is required to examine the role that cognitive function may have in determining various aspects of mood disorder recovery.

Processing speed and sustained attention in bipolar disorder and major depressive disorder: A systematic review and meta-analysis

OBJECTIVES

Cognitive impairment is a core feature of bipolar disorder (BD) and major depressive disorder (MDD). Deficits in processing speed (PS) and sustained attention (SA) may be particularly impaired and may underpin a broader profile of deficits, however current knowledge of the nature of these impairments is limited by heterogeneous results in the literature. Few reviews to date have attempted to disentangle sources of heterogeneity to assess the presence and magnitude of impairments in PS and SA in BD and MDD.

METHODS

One hundred and three studies were reviewed to examine performance in tests of PS and SA in BD (n = 3452) and MDD (n = 5461) compared to healthy controls (n = 8016). Neuropsychological methodology used in the literature was summarised. Data were meta-analysed to assess impairments in PS and SA for each neuropsychological test separately. Subgroup analysis was performed across mood states to investigate sources of heterogeneity.

RESULTS

Impairments were found across most neuropsychological tests, with small to large effect sizes for BD (range: d = 0.19-0.96) and MDD (range: d = 0.29-0.86). Impairments were present in symptomatic states and euthymia in most cases. Some outcome measures were not impaired in euthymia. Heterogeneity was observed for most neuropsychological tests and remained after separating by mood state. There inadequate data to meta-analyse some outcome measures, particularly for symptomatic groups.

CONCLUSION

Impairments in PS and SA in BD and MDD can be observed across most neuropsychological tests. Future research should further investigate the nature of these impairments across mood states, controlling for clinical confounds.

Impulsivity, decision-making, and risk behavior in bipolar disorder and major depression from bipolar multiplex families

OBJECTIVES

Bipolar disorder (BD) and major depressive disorder (MDD) are characterized by specific alterations of mood. In both disorders, alterations in cognitive domains such as impulsivity, decision-making, and risk-taking have been reported. Identification of similarities and differences of these domains in BD and MDD could give further insight into their etiology. The present study assessed impulsivity, decision-making, and risk-taking behavior in BD and MDD patients from bipolar multiplex families.

METHODS

Eighty-two participants (BD type I, n = 25; MDD, n = 26; healthy relatives (HR), n = 17; and healthy controls (HC), n = 14) underwent diagnostic interviews and selected tests of a cognitive battery assessing neurocognitive performance across multiple subdomains including impulsivity (response inhibition and delay aversion), decision-making, and risk behavior. Generalized estimating equations (GEEs) were used to analyze whether the groups differed in the respective cognitive domains.

RESULTS

Participants with BD and MDD showed higher impulsivity levels compared to HC; this difference was more pronounced in BD participants. BD participants also showed lower inhibitory control than MDD participants. Overall, suboptimal decision-making was associated with both mood disorders (BD and MDD). In risk-taking behavior, no significant impairment was found in any group.

LIMITATIONS

As sample size was limited, it is possible that differences between BD and MDD may have escaped detection due to lack of statistical power.

CONCLUSIONS

Our findings show that alterations of cognitive domains-while present in both disorders-are differently associated with BD and MDD. This underscores the importance of assessing such domains in addition to mere diagnosis of mood disorders.

Can cognitive inflexibility reduce symptoms of anxiety and depression? Promoting the structural nested mean model in psychotherapy research

OBJECTIVE

To estimate the causal effect of executive functioning on the remission of depression and anxiety symptoms in an observational dataset from a vocational rehabilitation program. It is also an aim to promote a method from the causal inference literature and to illustrate its value in this setting.

METHOD

With longitudinal (four-time points over 13 months) data from four independent sites, we compiled a dataset with 390 participants. At each time point, participants were tested on executive function and self-reported symptoms of anxiety and depression. We used g-estimation to evaluate whether objectively tested cognitive flexibility affected depressive/anxious symptoms and tested for moderation. Multiple imputations were used to handle missing data.

RESULTS

The g-estimation showed a strong causal effect of cognitive inflexibility reducing depression and anxiety and modified by education level. In a counterfactual framework, a hypothetical intervention that could lower cognitive flexibility seemed to cause improvement in mental distress at the subsequent time-point (negative sign) for low education. The less flexibility, the larger improvement. For high education, the same but weaker effect was found, with a change in sign, negative during the intervention and positive during follow-up.

DISCUSSION

An unexpected and strong effect was found from cognitive inflexibility on symptom improvement. This study demonstrates how to estimate causal psychological effects with standard software in an observational dataset with substantial missing and shows the value of such methods.

A Review on Smartphone Keystroke Dynamics as a Digital Biomarker for Understanding Neurocognitive Functioning

Can digital technologies provide a passive unobtrusive means to observe and study cognition outside of the laboratory? Previously, cognitive assessments and monitoring were conducted in a laboratory or clinical setting, allowing for a cross-sectional glimpse of cognitive states. In the last decade, researchers have been utilizing technological advances and devices to explore ways of assessing cognition in the real world. We propose that the virtual keyboard of smartphones, an increasingly ubiquitous digital device, can provide the ideal conduit for passive data collection to study cognition. Passive data collection occurs without the active engagement of a participant and allows for near-continuous, objective data collection. Most importantly, this data collection can occur in the real world, capturing authentic datapoints. This method of data collection and its analyses provide a more comprehensive and potentially more suitable insight into cognitive states, as intra-individual cognitive fluctuations over time have shown to be an early manifestation of cognitive decline. We review different ways passive data, centered around keystroke dynamics, collected from smartphones, have been used to assess and evaluate cognition. We also discuss gaps in the literature where future directions of utilizing passive data can continue to provide inferences into cognition and elaborate on the importance of digital data privacy and consent.

Childhood trauma and cognitive functioning in mood disorders: A systematic review

BACKGROUND

Cognitive impairment is a core feature of mood disorders and has been identified as an important treatment target. A better understanding of the factors contributing to cognitive impairment in mood disorders would be beneficial in developing interventions to address cognitive impairment. One key factor is childhood trauma. The aim of this review was to systematically synthesise and review research examining associations between reported childhood trauma and cognitive functioning in mood disorders.

METHODS

Studies in adult samples examining the relationship between objective cognitive function and reported childhood trauma in major depressive disorder and/or bipolar disorder (in-episode or euthymia) were identified. Searches were conducted on PubMed, Embase and PsycINFO until January 2022. A narrative review technique was used due to the heterogeneity of group comparisons, cognitive tests and data analysis across studies.

RESULTS

Seventeen studies met the criteria for inclusion (mood disorders N = 1723, healthy controls N = 797). Evidence for childhood trauma being related to poorer cognitive functioning was consistent across global cognitive functioning and executive function domains for euthymic patients and psychomotor speed for in-episode patients. There was mixed evidence for verbal learning and memory and executive function for in-episode patients. Identification of patterns within other domains was difficult due to limited number of studies.

CONCLUSION

Findings from this review suggest childhood trauma is associated with poorer cognitive functioning in people with mood disorders. Targeted interventions to improve cognition may be warranted for this group.

Lower memory specificity in individuals with dysphoria is not specific to autobiographical memory

BACKGROUND

A core cognitive attribute of depression is lower specificity in the expression of autobiographical memories. Despite interventions targeting memory specificity in depression, its underlying mechanisms are not yet fully understood. Depression also relates to poorer memory for episodic details; here we examine whether reduced specificity might simply reflect broader episodic memory deficits and weakened memory traces with the passage of time.

METHODS

Undergraduate students with and without symptoms of depression completed the Autobiographical Interview and prose-reading episodic memory tasks to assess both same-day and delayed memory.

RESULTS

Dysphoria and nondysphoria groups performed similarly on the tasks of immediate episodic and autobiographical memory; notably, the dysphoria group did not display evidence of lower specificity at this time point. After a delay, however, both groups demonstrated less specific memory responses on both memory tasks, and these declines were more pronounced in the group with dysphoria. That is, after a delay, individuals high in dysphoria showed a greater decrease in the quantity of specific event details reported on both the episodic and the autobiographical memory task. Additional analyses incorporating other clinical and cognitive measures indicated that these relations are largely unique to symptoms of depression.

LIMITATIONS

The sample comprised mostly female students; the study should be replicated with more diverse samples.

CONCLUSIONS

These findings support the claim that lower memory specificity is not peculiar to autobiographical memory, but rather, reflects impoverished memory more generally. This is an important consideration for theories and remedial strategies targeting memory specificity.

Validation of the Longitudinal Interval Follow-Up Evaluation for the Long-Term Measurement of Mood Symptoms in Bipolar Disorder

The long-term burden of symptoms is an important outcome in bipolar disorder (BD). A method which has minimal burden of assessment uses a retrospective interview, the Longitudinal Interval Follow-up Examination (LIFE), although this may be subject to problems with recall. This study examines the relationship between the retrospective LIFE scale and concurrently-rated mood rating scales in two clinical trials of 18 months of psychotherapy for patients with BD. The Montgomery-Asberg Depression Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) were administered every eight to nine weeks and the LIFE was carried out every 6 months. Correlations between scores on mood rating scales and at equivalent times on the LIFE were examined, as well as of potential clinical moderators. There were significant correlations between LIFE depression ratings and concurrent MADRS score (r = 0.57) and between LIFE mania ratings and YMRS score (r = 0.40). In determining "mild depression" on the MADRS, a receiver operating characteristics (ROC) analysis showed an AUC of 0.78 for LIFE scores. Correlations, particularly for depression scores, were high even when the LIFE rating was several months before the interview, suggesting that the LIFE has validity in examining the burden of mood symptoms over time, with relatively little burden of assessment. Future research should examine the relationship between symptom burden and quality of life measured in this way.

Relationship between baseline cognition and 18-month treatment response in bipolar disorder

BACKGROUND

To date, few studies have examined baseline cognitive function as a predictor of clinical outcome following treatment in bipolar disorder (BD). The aim of this analysis was therefore to examine the relationship between baseline cognitive function and treatment outcome in a sample of young adults with BD receiving Interpersonal Social Rhythm Therapy (IPSRT) or Specialist Supportive Care (SSC) with adjunctive pharmacotherapy.

METHODS

Eighty-six BD patients underwent baseline cognitive testing and completed 18 months of IPSRT or SCC. Univariate analyses examined the relationship between baseline cognitive function (global and individual cognitive domains) and change in mood symptom burden, and psychosocial functioning, from baseline to treatment-end.

RESULTS

Baseline global cognition was not predictive of change in mood symptom burden over 18 months of treatment. However, poorer baseline psychomotor speed performance was associated with less improvement in mood symptom burden at treatment-end. Neither baseline global cognition nor individual cognitive domain scores were associated with change in psychosocial functioning.

LIMITATIONS

Due to the exploratory nature of the study, correction was not made for multiple comparisons. Data was obtained from a relatively small sample and has been the subject of prior analysis, thereby increasing the likelihood of chance findings.

CONCLUSION

Although global cognition was not associated with outcome, when examining individual domains, poorer baseline psychomotor speed predicted less change in mood symptom burden following 18-months of psychotherapy and pharmacotherapy. This suggests that pre-treatment measures of psychomotor speed may help to identify those who require additional, and more targeted, intervention. Further large-scale research is required.

Speech Understanding in Manic and Depressive Episodes of Mood Disorders

OBJECTIVE

The aim of this study was to assess the perception of speech in adverse acoustic conditions during manic and depressive episodes of mood disorders.

METHODS

Forty-three patients with bipolar disorder (mania, N=20; depression, N=23) and 32 patients with unipolar depression were included for analyses. Thirty-five participants served as the control group. The study of speech understanding was carried out using the Polish Sentence Matrix Test, allowing for the determination of the speech reception threshold (SRT). The test was performed in the clinical groups both during an acute episode and remission; during remission, patients underwent audiometric evaluation.

RESULTS

Compared with control subjects, patients with mood disorders had worse speech understanding (higher SRT), regardless of the episode or remission. A manic episode in the course of bipolar disorder was not associated with worse speech understanding compared with remission of mania. However, an episode of depression in the course of both bipolar disorder and unipolar depression was associated with worse speech understanding compared with remission of depression. In bipolar depression, this correlated with age, duration of the disorder, number of episodes, and number of hospitalizations, as well as in remission with age and duration of illness. In unipolar depression, poor speech understanding was more severe in individuals with hearing impairment.

CONCLUSIONS

These findings revealed that patients with mood disorders had impaired speech understanding, even while in remission, and manic episodes in the course of bipolar disorder were not associated with impaired speech understanding compared with mania remission.

Current Evidence and Theories in Understanding the Relationship between Cognition and Depression in Childhood and Adolescence: A Narrative Review

The present narrative review has covered the current evidence regarding the role of cognitive impairments during the early phase of major depressive disorder (MDD), attempting to describe the cognitive features in childhood, adolescence and in at-risk individuals. These issues were analyzed considering the trait, scar and state hypotheses of MDD by examining the cold and hot dimensions, the latter explained in relation to the current psychological theoretical models of MDD. This search was performed on several electronic databases up to August 2022. Although the present review is the first to have analyzed both cold and hot cognitive impairments considering the trait, scar and state hypotheses, we found that current evidence did not allow to exclusively confirm the validity of one specific hypothesis since several equivocal and discordant results have been proposed in childhood and adolescence samples. Further studies are needed to better characterize possible cognitive dysfunctions assessing more systematically the impairments of cold, hot and social cognition domains and their possible interaction in a developmental perspective. An increased knowledge on these topics will improve the definition of clinical endophenotypes of enhanced risk to progression to MDD and, to hypothesize preventive and therapeutic strategies to reduce negative influences on psychosocial functioning and well-being.

Can cognition help predict suicide risk in patients with major depressive disorder? A machine learning study

BACKGROUND

Previous studies suggest that deficits in cognition may increase the risk of suicide. Our study aims to develop a machine learning (ML) algorithm-based suicide risk prediction model using cognition in patients with major depressive disorder (MDD).

METHODS

Participants comprised 52 depressed suicide attempters (DSA) and 61 depressed non-suicide attempters (DNS), and 98 healthy controls (HC). All participants were required to complete a series of questionnaires, the Suicide Stroop Task (SST) and the Iowa Gambling Task (IGT). The performance in IGT was analyzed using repeated measures ANOVA. ML with extreme gradient boosting (XGBoost) classification algorithm and locally explanatory techniques assessed performance and relative importance of characteristics for predicting suicide attempts. Prediction performances were compared with the area under the curve (AUC), decision curve analysis (DCA), and net reclassification improvement (NRI).

RESULTS

DSA and DNS preferred to select the card from disadvantageous decks (decks "A" + "B") under risky situation (p = 0.023) and showed a significantly poorer learning effect during the IGT (F = 2.331, p = 0.019) compared with HC. Performance of XGBoost model based on demographic and clinical characteristics was compared with that of the model created after adding cognition data (AUC, 0.779 vs. 0.819, p > 0.05). The net benefit of model was improved and cognition resulted in continuous reclassification improvement with NRI of 5.3%. Several clinical dimensions were significant predictors in the XGBoost classification algorithm.

LIMITATIONS

A limited sample size and failure to include sufficient suicide risk factors in the predictive model.

CONCLUSION

This study demonstrate that cognitive deficits may serve as an important risk factor to predict suicide attempts in patients with MDD. Combined with other demographic characteristics and attributes drawn from clinical questionnaires, cognitive function can improve the predictive effectiveness of the ML model. Additionally, explanatory ML models can help clinicians detect specific risk factors for each suicide attempter within MDD patients. These findings may be helpful for clinicians to detect those at high risk of suicide attempts quickly and accurately, and help them make proactive treatment decisions.

Depressive-like behavior accompanies neuroinflammation in an animal model of bipolar disorder symptoms induced by ouabain

INTRODUCTION

A previous study from our Laboratory showed no alteration in inflammatory parameters seven days after ouabain (OUA) administration, a Na⁺K⁺ATPase inhibitor, which was previously considered only a mania model. However, the administration of OUA in rats was recently validated as a model of bipolar disorder (BD) symptoms, demonstrating that 14 days after single intracerebroventricular (ICV) administration, OUA also induces depressive-like behavior. Therefore, it is important to investigate the long-term effect of OUA on inflammatory parameters since this mechanism seems to play a key role in BD physiopathology.

METHODS

Adult male Wistar rats received a single ICV administration of OUA or artificial cerebrospinal fluid (aCSF). From the fourth day after the ICV infusion, the rats received saline or Lithium (Li) for 14 days. The open-field test was performed on the 7th day after OUA. On the 14th day, locomotion was re-evaluated, and the forced swimming test (FST) was used to evaluate depressive-like behavior. Inflammatory parameters were assessed in the frontal cortex and hippocampus.

RESULTS

OUA increased the locomotion of rats after seven days, considered a mania-like behavior. In the FST, OUA increased the time of immobility on the 14th day, considered a depressive-like behavior. Li reversed the mania-like behavior and partially reversed the depressive-like behavior. Furthermore, OUA increased the levels of interleukin (IL)-1β, IL-6, IL-10, TNF-α, and CINC-1 in the frontal cortex and hippocampus. Li treatment reverses all these inflammatory alterations.

CONCLUSION

This study suggests that the long-term Na⁺K⁺ATPase inhibition effects induce depressive-like behavior, which was accompanied by inflammation in the BD symptoms model.

Computerized Working Memory Training in Remission From Major Depressive Disorder: Effects on Emotional Working Memory, Processing Speed, Executive Functions, and Associations With Symptoms

Introduction

Remission from major depressive disorder (MDD) is associated with residual symptoms related to reduced functioning, quality of life, and relapse risk. Previous studies have raised questions about mechanisms involved-in and affected by cognitive training. This study investigated the associations and changes among depressive symptoms, rumination, processing speed (PS), executive functioning (EF), and emotional working memory (e-WM) pre- post computerized working memory training (CWMT).

Method

Twenty-nine remitted participants were included in a pre- post pilot study of within-subject effects of online CWMT. A total of 20 participants completed the intervention and pre- post tests of EF and PS, e-WM, in addition to symptom and rumination measures. Associations between changes in symptoms and cognition were investigated pre- post. Associations between improvements in CWMT, depression history, and changes in cognition were explored. Hypotheses and statistics were preregistered before data were analyzed.

Results

Manipulation of negatively valanced stimuli in e-WM showed an inverse association with rumination pre-intervention, but the association disappeared post-intervention. Cognitive functioning improved in most conditions with largest effects in EF. Symptoms did not change in the remitted sample. CWMT improvements were related to improvements in some aspects of EF and PS, but also to worse self-reported attention. Depression history was related to less improvement in EF.

Limitations

Sample size was small and there was dropout from the study. There was no control group, thus precluding practice and placebo effects and causal relationships.

Conclusions

Computerized WM training improves cognitive functions and could influence associations between e-WM and rumination. This could counteract functional impairment following MDD.

Impact of cognitive remediation on the prediction of employment outcomes in severe mental illness

OBJECTIVE

Cognitive functioning is a potent predictor of work in people with a severe mental illness, including those receiving vocational services. Cognitive remediation has been shown to improve cognitive functioning and work outcomes in people receiving vocational services. However, it is unknown whether it reduces the strength of cognitive functioning as a predictor of work outcomes compared to people receiving vocational services alone.

METHOD

Data were pooled from five randomized controlled trials evaluating the effects of adding cognitive remediation to vocational rehabilitation vs. vocational services alone. A battery of baseline cognitive functioning measures was examined to identify predictors of competitive work outcomes over the following two years. Study condition (i.e., receipt of cognitive remediation) was included in the analyses to evaluate whether cognitive functioning was a weaker predictor of work outcomes in people receiving cognitive remediation compared to those receiving vocational services alone.

RESULTS

Cognitive functioning was a stronger predictor of wages earned and weeks worked in participants receiving vocational services alone than those who also received cognitive remediation. Cognitive functioning did not predict job acquisition in either study condition.

CONCLUSION

Cognitive remediation may improve employment outcomes in people receiving vocational services in part by reducing the adverse effects of impaired cognitive functioning on work performance.

A randomised controlled trial of psychotherapy and cognitive remediation to target cognition in mood disorders

OBJECTIVE

To examine the impact of a treatment package combining Interpersonal and Social Rhythm Therapy (IPSRT) and cognitive remediation (CR), vs IPSRT alone, on cognition, functioning, and mood disturbance outcomes in mood disorders.

METHODS

A pragmatic randomised controlled trial in adults with bipolar disorder (BD) or major depressive disorder (MDD), recently discharged from mental health services in Christchurch, New Zealand, with subjective cognitive difficulties. Individuals were randomised to a 12-month course of IPSRT with CR (IPSRT-CR), or without CR (IPSRT). In IPSRT-CR, CR was incorporated into therapy sessions from approximately session 5 and continued for 12 sessions. The primary outcome was change in Global Cognition (baseline to 12 months).

RESULTS

Sixty-eight individuals (BD n = 26, MDD n = 42; full/partial remission n = 39) were randomised to receive IPSRT-CR or IPSRT (both n = 34). Across treatment arms, individuals received an average of 23 IPSRT sessions. Change in Global Cognition did not differ between arms from baseline to treatment-end (12 months). Psychosocial functioning and longitudinal depression symptoms improved significantly more in the IPSRT compared with IPSRT-CR arm over 12 months, and all measures of functioning and mood symptoms showed moderate effect size differences favouring IPSRT (0.41-0.60). At 18 months, small to moderate, non-significant benefits (0.26-0.47) of IPSRT vs IPSRT-CR were found on functioning and mood outcomes.

CONCLUSIONS

Combining two psychological therapies to target symptomatic and cognitive/functional recovery may reduce the effect of IPSRT, which has implications for treatment planning in clinical practice and for CR trials in mood disorders.

Randomised controlled trial of Interpersonal and Social Rhythm Therapy and group-based Cognitive Remediation versus Interpersonal and Social Rhythm Therapy alone for mood disorders: study protocol

BACKGROUND

Individuals with mood disorders frequently experience cognitive impairment, which impacts on the long-term trajectory of the disorders, including being associated with persisting difficulties in occupational and psychosocial functioning, residual mood symptoms, and relapse. Current first-line treatments for mood disorders do little to improve cognitive function. Targeting cognition in clinical research is thus considered a priority. This protocol outlines a prospectively-registered randomised controlled trial (RCT) which examines the impact of adding group-based Cognitive Remediation (CR) to Interpersonal and Social Rhythm Therapy (IPSRT-CR) for individuals with mood disorders.

METHODS

This is a pragmatic, two-arm, single-blinded RCT comparing IPSRT-CR with IPSRT alone for adults (n = 100) with mood disorders (Major Depressive Disorder or Bipolar Disorder) with subjective cognitive difficulties, on discharge from Specialist Mental Health Services in Christchurch, New Zealand. Both treatment arms will receive a 12-month course of individual IPSRT (full dose = 24 sessions). At 6 months, randomisation to receive, or not, an 8-week group-based CR programme (Action-based Cognitive Remediation - New Zealand) will occur. The primary outcome will be change in Global Cognition between 6 and 12 months (treatment-end) in IPSRT-CR versus IPSRT alone. Secondary outcomes will be change in cognitive, functional, and mood outcomes at 6, 12, 18, and 24 months from baseline and exploratory outcomes include change in quality of life, medication adherence, rumination, and inflammatory markers between treatment arms. Outcome analyses will use an intention-to-treat approach. Sub-group analyses will assess the impact of baseline features on CR treatment response. Participants' experiences of their mood disorder, including treatment, will be examined using qualitative analysis.

DISCUSSION

This will be the first RCT to combine group-based CR with an evidence-based psychotherapy for adults with mood disorders. The trial may provide valuable information regarding how we can help promote long-term recovery from mood disorders. Many issues have been considered in developing this protocol, including: recruitment of the spectrum of mood disorders, screening for cognitive impairment, dose and timing of the CR intervention, choice of comparator treatment, and choice of outcome measures.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry, ACTRN12619001080112 . Registered on 6 August 2019.

A scoping review of near infrared spectroscopy studies employing a verbal fluency task in bipolar disorder

BACKGROUND

Deficits in cognitive functioning, including attention, memory, and executive functions, along with impairments in language production, are present in patients with bipolar disorder (BD) patients during mood phases, but also during euthymia.Verbal fluency tasks (VFTs), being able to evaluate integrity of a wide range of cognitive domains and represent, can be used to screen for these disturbances. Neuroimaging studies, including Near-InfraRed Spectroscopy (NIRS), have repeatedly showed widespread alterations in the prefrontal and temporal cortex during the performance of VFTs in BD patients. This review aims to summarize the results of NIRS studies that evaluated hemodynamic responses associated with the VFTs in prefrontal and temporal regions in BD patients.

METHODS

We performed a scoping review of studies evaluating VFT-induced activation in prefrontal and temporal regions in BD patients, and the relationship between NIRS data and various clinical variables.

RESULTS

15 studies met the inclusion criteria. In BD patients, compared to healthy controls, NIRS studies showed hypoactivation of the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and anterior temporal regions. Moreover, clinical variables, such as depressive and social adaptation scores, were negatively correlated with hemodynamic responses in prefrontal and temporal regions, while a positive correlation were reported for measures of manic symptoms and impulsivity.

LIMITATIONS

The heterogeneity of the studies in terms of methodology, study design and clinical characteristics of the samples limited the comparability of the findings.

CONCLUSIONS

Given its non-invasiveness, good time-resolution and no need of posturalconstraint, NIRS technique could represent a useful tool for the evaluation of prefrontal and temporal haemodynamic correlates of cognitive performances in BD patients.

The relationship between physical activity, BMI, circadian rhythm, and sleep with cognition in bipolar disorder

BACKGROUND

Cognitive deficits affect a significant proportion of patients with bipolar disorder (BD). Problems with sustained attention have been found independent of mood state and the causes are unclear. We aimed to investigate whether physical parameters such as activity levels, sleep, and body mass index (BMI) may be contributing factors.

METHODS

Forty-six patients with BD and 42 controls completed a battery of neuropsychological tests and wore a triaxial accelerometer for 21 days which collected information on physical activity, sleep, and circadian rhythm. Ex-Gaussian analyses were used to characterise reaction time distributions. We used hierarchical regression analyses to examine whether physical activity, BMI, circadian rhythm, and sleep predicted variance in the performance of cognitive tasks.

RESULTS

Neither physical activity, BMI, nor circadian rhythm predicted significant variance on any of the cognitive tasks. However, the presence of a sleep abnormality significantly predicted a higher intra-individual variability of the reaction time distributions on the Attention Network Task.

CONCLUSIONS

This study suggests that there is an association between sleep abnormalities and cognition in BD, with little or no relationship with physical activity, BMI, and circadian rhythm.

Neuropsychological predictors of vocational rehabilitation outcomes in individuals with major depression: A scoping review

BACKGROUND

Major depression is one of the leading causes of disability and limited capacity to work. Neuropsychological impairment is a common symptom in acute and remitted major depression and is associated with poor psychosocial functioning. This scoping review aimed to identify research on the role of neuropsychological functioning in outcomes of vocational rehabilitation programs in individuals with depression.

METHODS

We report on the conduct of this pre-registered (https://osf.io/5yrnf) scoping review in accordance with PRISMA-ScR guidelines. PubMed and PsychInfo were systematically searched for English or German research articles published between 1990 and September 2021 that studied objective neuropsychological tests as predictors of vocational rehabilitation interventions and included participants with depression.

RESULTS

The systematic literature search yielded no studies that specifically targeted subjects with major depression. However, eight articles published since 2016 were included in the review, analyzing data from five trials that evaluated the effectiveness of supported employment in North America and Europe in severe mental illnesses. An estimated 31% of the total number of participants included (n = 3,533) had major depression. Using a variety of cognitive tests and covariates, seven articles found that neuropsychological functioning - especially global cognition scores, verbal and visual learning and memory - significantly predicted vocational outcomes of rehabilitation programs.

CONCLUSION

Despite a lack of studies specifically targeting major depressive disorder, the identified literature suggests that higher baseline neuropsychological functioning predicts better vocational outcomes of supported employment programs in individuals with depression. In clinical practice, additional neuropsychological modules during return-to-work interventions might be helpful for vocational outcomes of such programs.

Changes in Mood, Anxiety, and Cognition with Polycystic Ovary Syndrome Treatment: A Longitudinal, Naturalistic Study

PURPOSE

Individuals with polycystic ovary syndrome (PCOS) are at increased risk of depression and anxiety symptoms and impairment in aspects of cognitive function. However, there is little evidence regarding effects of standard treatment for PCOS on these features of the syndrome. The aim of this study was to examine the effect of 12 weeks of naturalistic treatment of PCOS, with usual medications, on depression symptoms, anxiety symptoms and cognitive function.

PATIENTS AND METHODS

Thirty-three participants with PCOS received 12 weeks of individualised treatment based on clinical presentation. Changes in depression and anxiety symptoms were assessed with the self-report Hospital Anxiety and Depression Scale at baseline and 12 weeks, and cognitive function was assessed at the same time-points with a battery of tests spanning cognitive domains of verbal learning and memory, visuospatial learning and memory, psychomotor speed, attention and executive function. Outcomes were compared with a control group of 40 healthy participants.

RESULTS

Participants with PCOS (mean age = 29.2 years; mean Body Mass Index = 27.4) were treated with a variety of medications, predominantly spironolactone (n = 22) and oral contraceptives (n = 16). Depression and anxiety symptoms improved significantly over the course of treatment, with moderate effect sizes (Cohen's d 0.43-0.55, p < 0.05). Effect sizes of the difference in change from that of the control group were moderate but did not reach statistical significance. Women undergoing PCOS treatment demonstrated significant improvements in aspects of cognitive function, but improvement did not differ significantly from controls and effect size changes were similar, suggesting practise effects in both groups.

CONCLUSION

Our study provides preliminary evidence that treatment of PCOS may be associated with improvement in psychiatric aspects of the syndrome, particularly depressive symptoms.

Cognitive Impairment and Neurocognitive Profiles in Major Depression-A Clinical Perspective

Increasingly, studies have investigated cognitive functioning from the perspective of acute state- to remitted phases of Major Depressive Disorder (MDD). Some cognitive deficits observed in the symptomatic phase persist in remission as traits or scars. The etiological origin and clinical consequences of the neurocognitive profiles reported in the literature are still unclear and may vary across populations. Deficits are suspected to influence the association between MDD and neurodegenerative disorders and could thus be of particular clinical consequence. The aim of this review is to describe the clinical neuropsychological profile in MDD and how it is related to research during the past decade on cognitive deficits in MDD from a state, trait, and scar perspective. This review, with a clinical perspective, investigates research from the past decade regarding cognitive functioning in MDD in a long-term perspective. We focus on the clinical manifestation of deficits, and the potential neurodegenerative consequences of the neurocognitive profile in MDD. Searches in Medline, PsycINFO and Embase were conducted targeting articles published between 2010 and 2020. Examination of the evidence for long-lasting neurocognitive deficits in major depression within the cognitive domains of Memory, Executive Functions, Attention, and Processing Speed was conducted and was interpreted in the context of the State, Scar and Trait hypotheses. Defining the neurocognitive profiles in MDD will have consequences for personalized evaluation and treatment of residual cognitive symptoms, and etiological understanding of mood disorders, and treatments could potentially reduce or delay the development of neurodegenerative disorders.

Emotional cognition subgroups in mood disorders: Associations with familial risk

Patients with mood disorders show heterogeneity in non-emotional cognition. However, it is unclear whether emotional cognition (EC) is characterised by similar heterogeneity. We aimed to investigate the heterogeneity in EC among remitted patients with mood disorders and explore its association with familial risk. Data from 269 partially or fully remitted patients with mood disorders, 87 of their unaffected relatives (UR) and 203 healthy controls (HC) were pooled from two cohort studies. Hierarchical cluster analysis was conducted using the EC data from patients. UR were categorised into groups consistent with their affected relatives' cluster assignment. Clusters were compared to HC on EC, non-emotional cognition, clinical characteristics and functioning.  We identified three clusters: an 'emotionally preserved' (57%), an 'emotionally blunted' (26%) and an 'emotionally volatile' cluster (17%). 'Emotionally blunted' and 'emotionally volatile' patients also presented more deficits in non-emotional cognition (global cognition read z=-0.3 and -0.5 respectively). Relatives of 'emotionally preserved' patients were more successful at dampening negative emotions (p=.01, d=0.39, 95% CI [-0.76,-0.09]), whereas UR of 'emotionally impaired' patients underperformed in verbal fluency (p=.03, d=0.46, 95% CI [.03, 0.68]) compared to HC. The existence of impaired EC groups in remitted mood disorder highlights a need to screen for and treat EC in mood disorders. Improved ability to dampen emotions in UR of 'emotionally preserved' patients may reflect a resilience marker while impaired verbal fluency in UR of 'emotionally impaired' patients may reflect distinct genetic risk profiles in these EC subgroups.

Systematic review of the effects of evidence-based psychotherapies on neurocognitive functioning in mood disorders

OBJECTIVE

Neurocognitive impairment is considered a core feature of mood disorders. Research has shown that neurocognitive impairment often persists beyond mood symptom resolution and can have significant deleterious effects on interpersonal relationships, academic achievement, occupational functioning and independent living. As such, neurocognitive impairment has become an important target for intervention. In this systematic review, we aimed to examine the extant literature to ascertain whether current standard evidence-based psychotherapies can improve neurocognitive functioning in mood disorders.

METHOD

Studies examining changes in neurocognitive functioning following evidence-based psychotherapy were identified using MEDLINE, PsycINFO and Web of Science databases. Given the heterogeneity of study procedures, treatment protocols and patient samples, a narrative rather than meta-analytic review technique was employed.

RESULTS

Nineteen studies (21 articles) met inclusion criteria. There was preliminary evidence of improved executive functioning following evidence-based psychotherapy for Major Depressive Disorder and Bipolar Disorder. There was also some signal of reduced negative biases in emotional information processing following psychotherapy in depression. Due to methodological variability across studies however, it was difficult to draw clear conclusions.

CONCLUSION

Findings from the current review suggest that evidence-based psychotherapies may influence some aspects of neurocognitive functioning in mood disorders. This continues to be an ongoing area of importance and warrants further research.

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.

The Cognitive Difficulties Scale (CDS): Psychometric Characteristics in a Clinical Referral Sample

OBJECTIVE

To evaluate the psychometric characteristics of the Cognitive Difficulties Scale (CDS), a 39-item Likert-type self-report instrument that requires a fifth grade reading level. The CDS is a popular instrument that has been shown to predict cognitive decline in older persons.

METHOD

Participants were 512 consecutive outpatient referrals (71% women, mean age 60.6, and education 14.6 years) for a neuropsychological examination in a memory disorders clinic as part of a broader neurodiagnostic workup for cognitive decline. A principal components analysis was followed by a varimax rotation (Kaiser). Factor scores were investigated in relation to multiple internal and external criteria including demographics, Cronbach's alpha, Digit Span, and Wechsler Memory Scale-IV Logical Memory (LM) and Visual Reproduction (VR), and Minnesota Multiphasic Personality Inventory (MMPI)-2 measures of depression, anxiety, somatic preoccupations, and thought disturbance.

RESULTS

Six dimensions of cognitive complaint emerged accounting for 64% of the variance: attention/concentration, praxis, prospective memory, speech problems, memory for people's names, and temporal orientation. The factors showed good internal consistency (alphas > .850). Correlations with Digit Span, LM, and VR were all nonsignificant. CDS scores were associated with MMPI-2 measures of anxiety, depression, somatic preoccupation, and thought disturbance. Percentiles and T-scores were derived for raw scores on the CDS and its six component subscales.

CONCLUSION

The CDS is a multidimensional measure of subjective cognitive complaints that provides clinicians with a psychometrically sound basis for deriving a profile with six subscale scores. The test has clinical utility and is a potentially useful tool in research involving age-related cognitive changes and meta-cognition.

Associations between cognitive impairment and illness awareness in fully remitted bipolar outpatients

The euthymic state of bipolar disorder is often characterized by impaired cognitive function. In this investigation, we hypothesized that subjective cognitive function is impaired and illness awareness is inadequate and we further explored the associations among cognitive complaints, objective cognitive functions, and current illness awareness in Japanese patients. Twenty-seven patients in remission and 27 healthy subjects were recruited in this study. The Japanese version of the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) and Scale to Assess Unawareness in Mental Disorders (Japanese, SUMD-J) were used to assess each patient. All patients underwent neuropsychological tests for the assessment of objective cognitive functions. Only SUMD2.C (current awareness of the effects of medication) was significantly correlated with COBRA, and the objective cognitive assessments, Word Fluency Test and Stroop Test Reaction Time, represented significant correlations with SUMD1.C (current awareness of mental illness). In remitted bipolar outpatients, both the objective and subjective cognitive functions were found to be associated with illness awareness. However, subjective and objective cognitive functions differed in the related illness awareness subscales in fully remitted bipolar outpatients.

The 2020 Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders

OBJECTIVES

To provide advice and guidance regarding the management of mood disorders, derived from scientific evidence and supplemented by expert clinical consensus to formulate s that maximise clinical utility.

METHODS

Articles and information sourced from search engines including PubMed, EMBASE, MEDLINE, PsycINFO and Google Scholar were supplemented by literature known to the mood disorders committee (e.g. books, book chapters and government reports) and from published depression and bipolar disorder guidelines. Relevant information was appraised and discussed in detail by members of the mood disorders committee, with a view to formulating and developing consensus-based recommendations and clinical guidance. The guidelines were subjected to rigorous consultation and external review involving: expert and clinical advisors, key stakeholders, professional bodies and specialist groups with interest in mood disorders.

RESULTS

The Royal Australian and New Zealand College of Psychiatrists mood disorders clinical practice guidelines 2020 (MDcpg²⁰²⁰) provide up-to-date guidance regarding the management of mood disorders that is informed by evidence and clinical experience. The guideline is intended for clinical use by psychiatrists, psychologists, primary care physicians and others with an interest in mental health care.

CONCLUSION

The MDcpg²⁰²⁰ builds on the previous 2015 guidelines and maintains its joint focus on both depressive and bipolar disorders. It provides up-to-date recommendations and guidance within an evidence-based framework, supplemented by expert clinical consensus.

MOOD DISORDERS COMMITTEE

Gin S Malhi (Chair), Erica Bell, Darryl Bassett, Philip Boyce, Richard Bryant, Philip Hazell, Malcolm Hopwood, Bill Lyndon, Roger Mulder, Richard Porter, Ajeet B Singh and Greg Murray.

Influence of the GABA Receptor Subunit Gene Polymorphism and Childhood Sexual Abuse on Processing Speed in Major Depression and Suicide Attempt

Background: Suicide is moderately heritable and also more common in those who report childhood abuse. Previously, it was found that allele A of GABRG2 (GABA A receptor subunit gamma2) polymorphism rs211034 was protective in a suicide attempt (SA). Hence, it was proposed that rs211034 may interact with childhood trauma to influence cognitive deficits related to SA or depression risk. Genetic variants may predict the benefits of certain cognitive treatments. Methods: A total of 52 individuals who had attempted suicide, 59 individuals with major depressive disorder (MDD) or bipolar depression who had not previously attempted suicide, and 90 healthy volunteers were subjected to the modified Suicide Stroop task and were clinically assessed using the Childhood Trauma Questionnaire (CTQ) and Hamilton Depression Scale-24 items (HAMD-24). rs211034 was genotyped using Sanger sequencing. Results: After correcting for covariates, depressed participants displayed longer reaction times for all emotional conditions, including suicide-related words, compared with healthy controls. Depressed suicide attempters displayed longer reaction times for negative words than depressed non-attempters. Depressed non-attempters displayed higher interference scores for negative words compared with healthy controls. There was an interaction between rs211034 risk allele and the effects of reported childhood sexual abuse (CSA) on reaction time for all emotional words and suicide-related words. Carriers of the rs211034 risk allele A exhibited shorter reaction times, but the protective effects of this allele were eliminated in those exposed to reported CSA. Conclusion: Only limited results were found regarding effects of a past suicide attempt on response times to emotional and suicide-related words, but there was an overall effect of major depression on slower response time. Protective genetic effects of the rs211034 A allele on this slowing were eliminated in those with a history of sexual abuse during childhood. Further research is needed to better characterize the mechanisms underlying the effects of childhood trauma on these genetic effects.

A Longitudinal 5-Year Follow-Up Study of Cognitive Function After First Episode Major Depressive Disorder: Exploring State, Scar and Trait Effects

Major depression (MDD) is associated with cognitive deficits in processing speed and executive function (EF) following first episode (FE). It is unclear whether deficits are state or trait related. Studies following FE MDD over longer periods are lacking, making it uncertain how cognition and symptoms develop after the initial episode. The present study assessed cognitive function and symptoms 5 years following FE MDD. In addition, the study explored relationships between MDD symptoms, rumination, and cognitive deficits with regards to the trait, state, and scar perspective. Twenty-three participants with previous FE MDD, and 20 matched control participants were compared on Delis-Kaplan Executive Function System measures of processing speed and EF, in a 5-year longitudinal follow-up study. Correlations between current symptoms- and history of MDD, rumination, cognition were investigated. Findings indicated that cognitive deficits persisted with no clear signs of exacerbation after initial episode. Inhibition appeared independent of current and previous symptoms of depression. Processing speed was related to depressive- symptoms and rumination. In conclusion, results indicated persisting, stable deficits in both EFs and processing speed. Findings further suggest that depressive symptoms could be related to deficits in processing speed, indicating state effects. There was limited support for worsening of cognition after initial episode. Some aspects of EF like Inhibition could show persistent deficits independent of depressive symptoms indicating trait effects.

Emotion processing in depression and anxiety disorders in older adults: systematic review

BACKGROUND

Emotional cognition and effective interpretation of affective information is an important factor in social interactions and everyday functioning, and difficulties in these areas may contribute to aetiology and maintenance of mental health conditions. In younger people with depression and anxiety, research suggests significant alterations in behavioural and brain activation aspects of emotion processing, with a tendency to appraise neutral stimuli as negative and attend preferentially to negative stimuli. However, in ageing, research suggests that emotion processing becomes subject to a 'positivity effect', whereby older people attend more to positive than negative stimuli.

AIMS

This review examines data from studies of emotion processing in Late-Life Depression and Late-Life Anxiety to attempt to understand the significance of emotion processing variations in these conditions, and their interaction with changes in emotion processing that occur with ageing.

METHOD

We conducted a systematic review following PRISMA guidelines. Articles that used an emotion-based processing task, examined older persons with depression or an anxiety disorder and included a healthy control group were included.

RESULTS

In Late-Life Depression, there is little consistent behavioural evidence of impaired emotion processing, but there is evidence of altered brain circuitry during these processes. In Late-Life Anxiety and Post-Traumatic Stress disorder, there is evidence of interference with processing of negative or threat-related words.

CONCLUSIONS

How these findings fit with the positivity bias of ageing is not clear. Future research is required in larger groups, further examining the interaction between illness and age and the significance of age at disease onset.

Verbal Memory Performance in Depressed Children and Adolescents: Associations with EPA but Not DHA and Depression Severity

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been described as positively associated with cognitive functioning. Current meta-analyses have identified eicosapentaenoic acid (EPA) as potentially more effective than docosahexaenoic acid (DHA). An especially vulnerable subgroup that might benefit from these beneficial effects are depressed youths. In this study, we examined associations between red blood cell (RBC) DHA and EPA levels and depression severity and verbal memory performance in a sample of 107 moderately (n = 63) and severely (n = 44) depressed youths. The findings showed that youths with high RBC EPA levels had steeper learning curves compared to those with moderate or low RBC EPA levels (Pillai's Trace = 0.195, p = 0.027, η_p² = 0.097). No associations between RBC DHA levels or depression severity and verbal memory performance were observed. Our results further confirm previous findings indicating a more important role of EPA compared to DHA in relation to cognitive functioning. Future research should further investigate the differential role of EPA and DHA concerning cognitive functioning in depressed youths. Evidence supporting beneficial supplementation effects could potentially establish a recommendation for a natural and easily accessible intervention for cognitive improvement or remission.

Baseline predictors of cognitive change in the treatment of major depressive episode: systematic review

BACKGROUND

Cognitive impairment is a core feature of depression and has a negative effect on a person's functioning, in psychosocial and interpersonal areas, and on workforce performance. Cognitive impairment often persists, even with the remittance of mood symptoms. One potential way of improving treatment of cognitive impairment would be to identify variables that predict cognitive change in patients with depression.

AIMS

To systematically examine findings from studies that investigate baseline variables and how they predict, or correlate with, cognitive change in mood disorders, and to examine methodological issues from these studies.

METHOD

Studies that directly measured associations between at least one baseline variable and change in cognitive outcome in patients with current major depressive episode were identified using PubMed and Web of Science databases. Narrative review technique was used because of the heterogeneity of patient samples, outcome measures and study procedures. The review was registered on PROSPERO with registration number CRD42020150975.

RESULTS

Twenty-four studies met the inclusion criteria. Evidence from the present review for prediction of cognitive change from baseline variables was limited for demographic factors, with some preliminary evidence for depression, cognitive and biological factors. Identification of patterns across studies was difficult because of methodological variability across studies.

CONCLUSIONS

Findings from the present review suggest there may be some baseline variables that are useful in predicting cognitive change in mood disorders. This is an area warranting further research focus.

Neurophysiological markers of attention distinguish bipolar disorder and unipolar depression

BACKGROUND

Attentional deficits are common in both symptomatic and symptom-remitted patients with bipolar disorder (BP) and major depressive disorder (MDD). However, whether the level of neurocognitive impairment in attentional processing is different between these two disorders, or not, is still unclear. Thus, we investigated the P300 event-related potential component as a biomarker of cognitive dysfunction to differentiate BP and MDD.

METHODS

Twenty-three age and gender matched BP, 20 MDD and 23 healthy controls (HC) were part of a discovery cohort to identify neurophysiological differences between groups and build a classification model of these disorders. The replication of this model was then tested in an independent second cohort of 17 BP, 19 MDD and 19 HC. All participants were symptom-remitted for at least two weeks. We compared neural responses to target stimuli during an auditory oddball task, computing peak amplitude and latency of the P300 component extracted from the midline centro-parietal electrode.

RESULTS

BP had significantly smaller P300 amplitudes compared to both MDD and HC, whereas there were no differences between MDD and HC. The differences between groups were replicated in the second cohort, however the accuracy level of the classification model was only 53.5%.

LIMITATIONS

Small sample sizes may have led to low accuracy levels of the classification model.

CONCLUSION

Specific neural mechanisms of attention and context updating seem not to recover with symptom remission in BP. These findings contribute to the detection of a potential electrophysiological marker for BP, which may allow its differentiation from unipolar major depressive disorder.

S100B and brain derived neurotrophic factor in monozygotic twins with, at risk of and without affective disorders

BACKGROUND

The calcium binding protein S100B and brain derived neurotrophic factor (BDNF) are both biomarkers implicated in neuronal processes in the central nervous system and seem to be associated with affective disorders. Here we investigated both markers in a sample of monozygotic (MZ) twins with, at risk of and without affective disorders, aiming to evaluate whether these markers have a role as causal factors- or trait markers for affective disorders.

METHOD

We measured serum S100B and plasma BDNF levels in 204 monozygotic twins (MZ) with unipolar or bipolar disorder in remission or partial remission (affected), their unaffected co-twins (high-risk) and twins with no personal or family history of affective disorder (low-risk).

RESULTS

No significant group differences in S100B and BDNF levels were found between the three groups. Exploratory analysis revealed that higher S100B levels were correlated with lower cognitive performance.

LIMITATIONS

The cross-sectional design cannot elucidate the two neuronal biomarkers role as causal factors. We would have preferred a higher sample size in the high- and low-risk groups.

CONCLUSION

The present result did not support a role for S100B and BDNF as neither causal factors nor trait markers for affective disorders. Elevated S100B levels may associate with impaired cognition, but further studies are warranted.

Associations between cognitive impairment and P300 mean amplitudes in individuals with bipolar disorder in remission

Cognitive functions are often affected during the euthymic state of bipolar disorder (BD). In this study, we investigated the associations among cognitive complaints, objective cognitive functions, and the mean amplitudes of the P300 event-related potential (ERP) wave in individuals with BD. The study population comprised 33 individuals with BD who were in remission and was conducted at Hokkaido University Hospital, Sapporo, Japan. Cognitive complaints were assessed using the Japanese version of the tool named "cognitive complaints in bipolar disorder rating assessment (COBRA)", whereas objective cognitive functions were measured by neuropsychological tests. P300 mean amplitudes were investigated during two- and three-stimulus oddball tasks and showed significant correlations with neuropsychological test scores at all electrode locations, confirming that ERPs and objective cognitive tests that assessed attention and memory function tend to coincide; however, neither P300 amplitudes nor neuropsychological test scores were correlated with COBRA scores. ERPs most likely represent the neurophysiological basis for objective rather than subjective cognitive function in euthymic individuals. Thus, our results suggest that objective cognitive function is related more to P300 mean amplitude scores than subjective cognitive function in individuals with BD.

Cognitive Remediation for Outpatients With Recurrent Mood Disorders: A Feasibility Study

Current first-line treatments for mood disorders often improve mood symptoms but do little to reduce cognitive and functional impairment. This 10-week, uncontrolled, feasibility study evaluated a cognitive remediation (CR) intervention for individuals with recurrent mood disorders. Adults with recurrent major depressive disorder or bipolar disorder, who had recently been treated and discharged from specialized mental health services, were eligible for inclusion. Twenty patients completed the CR intervention, which involved weekly individual sessions with a therapist, as well as the practice of computerized CR exercises between sessions. The study assessed the acceptability of the assessment and treatment as well as outcomes in terms of mood symptoms, general functioning, and cognitive functioning. Patients reported that they were generally satisfied with the CR intervention and were close to reaching the recommended amount of practice between therapist-led sessions. The retention rate from baseline to posttreatment was 87%. When within-group effects were examined, large effect sizes over time (>0.9) were seen for 2 cognitive variables that measured executive function: Category Switching-Total Words and Total Switching Score. Findings from the current feasibility study will inform the development of a large randomized controlled trial of an adapted version of the CR intervention for mood disorders assessed in this preliminary study, with the goal of translating the intervention into clinical practice.

Investigating the neural basis of cognitive control dysfunction in mood disorders

OBJECTIVES

Dysfunction of cognitive control is a feature of both bipolar disorder (BP) and major depression (MDD) and persists through to remission. However, it is unknown whether these disorders are characterized by common or distinct disruptions of cognitive control function and its neural basis. We investigated this gap in knowledge in asymptomatic BP and MDD participants, interpreted within a framework of normative function.

METHODS

Participants underwent fMRI scans engaging cognitive control through a working memory task and completed a cognitive battery evaluating performance across multiple subdomains of cognitive control, including attention, impulsivity, processing speed, executive function, and memory. Analysis was performed in two stages: (i) cognitive control-related brain activation and deactivation were correlated with cognitive control performance in 115 healthy controls (HCs), then, (ii) significantly correlated regions from (i) were compared between 25 asymptomatic BP, 25 remitted MDD, and with 25 different HCs, matched for age and gender.

RESULTS

Impulsivity and executive function performance were significantly worse in BP compared to both MDD and HCs. Both BP and MDD had significantly poorer memory performance compared to HCs. Greater deactivation of the medial prefrontal cortex (MPFC) during the fMRI task was associated with better executive function in healthy controls. Significantly less deactivation in this region was present in both BP and MDD compared to HCs.

CONCLUSIONS

Failure to deactivate the MPFC, a key region of the default mode network, during working memory processing is a shared neural feature present in both bipolar and major depression and could be a source of common cognitive dysfunction.

The Relationship between Performance of Attention Task and Suicidal Ideation in Korean Patients with Mood Disorders

OBJECTIVE

We examined the performance of attention tests related to suicidal ideation in mood disorder patients and to explain the difference of attention test performance in relation to suicidal ideation after controlling clinical and psychological variables of mood disorder patients.

METHODS

Seventy-three in- and outpatients with major depressive disorder (n=41) or bipolar disorder (n=32) completed a self-rating questionnaire assessing socio-demographic characteristics, and clinical and psychological variables. Comprehensive Attention Test (CAT) also was conducted.

RESULTS

Thirty-three patients were the high-suicidal ideation (SI) group, and forty patients were the low-SI group. The errors of commission (CEs) of visual sustained attention in the high-SI group was 6.3 times higher on average than that of the low-SI group. After controlling for sex, age, and diagnosis, a higher number of CEs on visual sustained attention tasks predicted higher SI score. However, after controlling for sex, age, diagnosis, and depressive mood, this predictive ability was no longer observed.

CONCLUSION

This study showed that CE on the visual sustained attention task seems to influence suicidal ideation as a result of interaction with depressive symptoms.

Improvement in cognitive function in young people with bipolar disorder: Results from participants in an 18-month randomised controlled trial of adjunctive psychotherapy

OBJECTIVE

To examine the effects of 18 months of intensive stabilisation with medication management and Interpersonal and Social Rhythm Therapy or Non-specific Supportive Clinical Management on cognitive function in young people with bipolar disorder. Determinants of change in cognitive function over the 18 months of the trial were also examined.

METHOD

Patients aged 15-36 years with Bipolar I Disorder, Bipolar II Disorder and Bipolar Not Otherwise Specified were recruited. From a battery of cognitive tests, change scores for pre-defined domains of cognitive function were created based on performance at baseline and follow-up. Change was compared between the two therapy groups. Regression analysis was used to determine the impact of a range of clinical variables on change in cognitive performance between baseline and follow-up.

RESULTS

One hundred participants were randomised to Interpersonal and Social Rhythm Therapy (n = 49) or Non-specific Supportive Clinical Management (n = 51). Seventy-eight patients underwent cognitive testing at baseline and 18 months. Across both groups, there were significant improvements in a Global Cognitive Composite score, Executive Function and Psychomotor Speed domains from baseline to 18 months. Lower scores at baseline on all domains were associated with greater improvement over 18 months. Overall, there was no difference between therapies in change in cognitive function, either in a global composite score or change in domains.

CONCLUSION

While there was no difference between therapy groups, intensive stabilisation with psychological therapy was associated with improved cognitive function, particularly in those patients with poorer cognitive function at baseline. However, this was not compared with treatment as usual so cannot be attributed necessarily to the therapies.

Inflammation, brain structure and cognition interrelations among individuals with differential risks for bipolar disorder

Neuro-inflammation might impact on clinical manifestations and cognition function via changing the volumes of key brain structures such as the anterior cingulate cortex (ACC) in bipolar disorder (BD). In this study, we investigated the interrelations among interleukin (IL)-6 cytokine level, grey matter (GM) volume of the anterior cingulated cortex (ACC), and attention function among offspring of parents diagnosed with BD. The offspring were categorized as being either asymptomatic or symptomatic based on whether they manifested pre-defined sub-threshold mood symptoms. We found that the symptomatic offspring showed significantly higher serum levels of IL-6 than the asymptomatic offspring (F_{(1, 59)} = 67.65, p < 0.001). On the brain level, we obtained significant interactive effect of group and IL6 level on the ACC GM (P_FWE = 0.017). Specifically, the GM volume of the rostral ACC was negatively associated with the levels of IL-6 in the asymptomatic offspring (P_FWE = 0.021), but not the symptomatic offspring (P_FWE > 0.05). Mediation analyses revealed that the GM volume of the rostral ACC significantly mediated the negative association between the IL-6 levels and attention performance in the asymptomatic offspring (bootstrapping Confidence Interval (CI) = -6.0432 to -0.0731) but not the symptomatic offspring (bootstrapping CI = -0.3197 to 1.3423). Our data suggest that the asymptomatic and symptomatic bipolar offspring may exhibit different neurocognitive-inflammatory profiles, which could be further validated as viable biosignatures for BD risk and resilience.

Cognitive functioning as a predictor of response to comprehensive cognitive remediation

Cognitive remediation is aimed at reducing cognitive impairments in severe mental illnesses such as schizophrenia, but little is known about whether severity of cognitive impairment predicts benefit from this intervention. To address this question, this study aggregated data from five randomized controlled trials (N = 300) of a standardized comprehensive, multimodal outpatient cognitive remediation program, the Thinking Skills for Work program, and evaluated whether baseline level of cognitive impairment differentially predicted improvement in cognitive functioning following cognitive remediation vs. usual services. Using standardized scores of neuropsychological functioning to designate "low average," "moderate," and "severe" levels of cognitive impairment, participants with greater cognitive impairment were found to benefit differentially more from cognitive remediation than usual services compared to less cognitively impaired participants. The findings were unaffected by statistically controlling for participant demographic and clinical characteristics. The findings suggest that individuals with the greatest cognitive impairment, for whom cognitive remediation was developed, are also most likely to benefit from this intervention.

[Depressed, biased, forgetful: The interaction of emotional and cognitive dysfunctions in depression]

Major depressive disorder is characterized by changes in the emotional state, e. g. the diminished experience of positive emotions, as well as cognitive impairments such as concentration and memory difficulties. These emotional and cognitive dysfunctions are closely interrelated and play a key role for the development and maintenance of depressive symptoms. For instance, patients with depression show negatively biased information processing that affects attention and memory as well as their reaction to feedback. In addition, there is an increased motivation to avoid negatively evaluated conditions and at the same time a reduced motivation to approach positive goals. Furthermore, depressed patients often show a specific style of thinking, called rumination, which involves repeated, intensive thinking about the causes, consequences and symptoms of one's own negative feelings. In this review, the different relationships between emotional, motivational and cognitive symptoms of depressive patients will be presented and the influence of their interaction on cognitive performance will be discussed. The highlighted clinical relevance of emotional-cognitive dysfunctions should be considered more often in therapeutic interventions for depressed patients.

Structural changes in the hippocampus as a biomarker for cognitive improvements in neuropsychiatric disorders: A systematic review

Cognitive impairments are a core feature of several neuropsychiatric disorders. A common biomarker for pro-cognitive effects may provide a much-needed tool to select amongst candidate treatments targeting cognition. The hippocampus is a promising biomarker for target-engagement due to the illness-associated morphological hippocampal changes across unipolar disorder (UD), bipolar disorder (BD) and schizophrenia (SCZ). Following the PRISMA guidelines, we searched PubMed and Embase, for clinical trials targeting cognition across neuropsychiatric disorders, with longitudinal structural magnetic resonance imaging (MRI) measures of the hippocampus. Five randomized and three open-label trials were included. Hippocampal volume increases were associated with treatment-related cognitive improvement following treatment with erythropoietin across UD, BD and SCZ, lithium treatment in BD and aerobic exercise in SCZ. Conversely, an exercise intervention in UD showed no effect on hippocampal volume or cognition. Together, these observations point to hippocampal volume change as a putative biomarker-model for cognitive improvement. Future cognition trials are encouraged to include MRI assessments pre- and post-treatment to assess the validity of hippocampal changes as a biomarker for pro-cognitive effects.

Impairments in cognitive performance in chronic fatigue syndrome are common, not related to co-morbid depression but do associate with autonomic dysfunction

Objectives

To explore cognitive performance in chronic fatigue syndrome (CFS) examining two cohorts. To establish findings associated with CFS and those related to co-morbid depression or autonomic dysfunction.

Methods

Identification and recruitment of participants was identical in both phases, all CFS patients fulfilled Fukuda criteria. In Phase 1 (n = 48) we explored cognitive function in a heterogeneous cohort of CFS patients, investigating links with depressive symptoms (HADS). In phase 2 (n = 51 CFS & n = 20 controls) participants with co-morbid major depression were excluded (SCID). Furthermore, we investigated relationships between cognitive performance and heart rate variability (HRV).

Results

Cognitive performance in unselected CFS patients is in average range on most measures. However, 0–23% of the CFS sample fell below the 5th percentile. Negative correlations occurred between depressive symptoms (HAD-S) with Digit-Symbol-Coding (r = -.507, p = .006) and TMT-A (r = -.382, p = .049). In CFS without depression, impairments of cognitive performance remained with significant differences in indices of psychomotor speed (TMT-A: p = 0.027; digit-symbol substitution: p = 0.004; digit-symbol copy: p = 0.007; scanning: p = .034) Stroop test suggested differences due to processing speed rather than inhibition.

Both cohorts confirmed relationships between cognitive performance and HRV (digit-symbol copy (r = .330, p = .018), digit-symbol substitution (r = .313, p = .025), colour-naming trials Stroop task (r = .279, p = .050).

Conclusion

Cognitive difficulties in CFS may not be as broad as suggested and may be restricted to slowing in basic processing speed. While depressive symptoms can be associated with impairments, co-morbidity with major depression is not itself responsible for reductions in cognitive performance. Impaired autonomic control of heart-rate associates with reductions in basic processing speed.

Activation therapy for the treatment of inpatients with depression - protocol for a randomised control trial compared to treatment as usual

BACKGROUND

Inpatients with depression have a poor long term outcome with high rates of suicide, high levels of morbidity and frequent re-admission. Current treatment often relies on pharmacological intervention and focuses on observation to maintain safety. There is significant neurocognitive deficit which is linked to poor functional outcomes. As a consequence, there is a need for novel psychotherapeutic interventions that seek to address these concerns.

METHODS

We combined cognitive activation and behavioural activation to create activation therapy (AT) for the treatment of inpatient depression and conducted a small open label study which demonstrated acceptability and feasibility. We propose a randomised controlled trial which will compare treatment as usual (TAU) with TAU plus activation therapy for adult inpatients with a major depressive episode. The behavioural activation component involves therapist guided re-engagement with previously or potentially rewarding activities. The cognitive activation aspect utilises computer based exercises which have been shown to improve cognitive function.

DISCUSSION

The proposed randomised controlled trial will examine whether or not the addition of this therapy to TAU will result in a reduced re-hospitalisation rate at 12 weeks post discharge. Subjective change in activation and objectively measured change in activity levels will be rated, and the extent of change to neurocognition will be assessed.

TRIAL REGISTRATION

Unique trial number: U1111-1190-9517. Australian New Zealand Clinical Trials Registry (ANZCTR) number: ACTRN12617000024347p .

Associations between cognitive impairment and quality of life in euthymic bipolar patients

During the euthymic state in bipolar disorder, cognitive functions often remain affected. Specifically, subjective and objective cognitive impairment might distinctly affect patients' quality of life (QoL); however, this question had not been examined previously in Japanese patients. Therefore, the current study investigated the associations between cognitive complaints, QoL, and objective cognitive functions. Forty patients in remission were recruited from the Hokkaido University Hospital, Sapporo, Japan and assessed with the translated version of the cognitive complaints in bipolar disorder rating assessment (COBRA), medical outcomes study 36-item short-form health survey version 2 (SF-36v2), and Sheehan disability scale (SDS). The Japanese adult reading scale, Wisconsin card sorting test, word fluency, continuous performance test, trail making test (TMT), auditory verbal learning, and Stroop test evaluated objective cognitive functions. Significant correlations were observed between the COBRA, SF-36v2, and SDS results, as well as the TMT scores. Overall, euthymic patients were aware of their cognitive dysfunction, which could be understood in relation to the decrease in satisfaction in their daily life. Therefore, even mild cognitive impairments can have ramifications for patients in the euthymic state of bipolar disorder.

Empirical evidence for discrete neurocognitive subgroups in patients with non-psychotic major depressive disorder: clinical implications

BACKGROUND

Neuropsychological deficits are present across various cognitive domains in major depressive disorder (MDD). However, a consistent and specific profile of neuropsychological abnormalities has not yet been established.

METHODS

We assessed cognition in 170 patients with non-psychotic MDD using the Brief Assessment of Cognition in Schizophrenia and the scores were compared with those of 42 patients with schizophrenia as a reference for severity of cognitive impairment. Hierarchical cluster analysis was conducted to determine whether there are discrete neurocognitive subgroups in MDD. We then compared the subgroups in terms of several clinical factors and social functioning.

RESULTS

Three distinct neurocognitive subgroups were found: (1) a mild impairment subgroup with near-normative performance and mild dysfunction in motor speed; (2) a selective impairment subgroup, which exhibited preserved working memory and executive function, but moderate to severe deficits in verbal memory, motor speed, verbal fluency, and attention/information processing speed; and (3) a global impairment subgroup with moderate to severe deficits across all neurocognitive domains, comparable with deficits in schizophrenia. The global impairment subgroup was characterized by lower pre-morbid intelligence quotient (IQ). Moreover, a significant difference between groups was observed in premorbid IQ (p = 0.003), antidepressant dose (p = 0.043), antipsychotic dose (p = 0.013), or anxiolytic dose (p < 0.001).

CONCLUSIONS

These results suggest the presence of multiple neurocognitive subgroups in non-psychotic MDD with unique profiles, one of which exhibits deficits comparable to those of schizophrenia. The results of the present study may help guide future efforts to target these disabling symptoms using different treatments.