Identifying and treating cognitive impairment in bipolar disorder

New Advances in the Pharmacology and Toxicology of Lithium: A Neurobiologically Oriented Overview

Over the last six decades, lithium has been considered the gold standard treatment for the long-term management of bipolar disorder due to its efficacy in preventing both manic and depressive episodes as well as suicidal behaviors. Nevertheless, despite numerous observed effects on various cellular pathways and biologic systems, the precise mechanism through which lithium stabilizes mood remains elusive. Furthermore, there is recent support for the therapeutic potential of lithium in other brain diseases. This review offers a comprehensive examination of contemporary understanding and predominant theories concerning the diverse mechanisms underlying lithium's effects. These findings are based on investigations utilizing cellular and animal models of neurodegenerative and psychiatric disorders. Recent studies have provided additional support for the significance of glycogen synthase kinase-3 (GSK3) inhibition as a crucial mechanism. Furthermore, research has shed more light on the interconnections between GSK3-mediated neuroprotective, antioxidant, and neuroplasticity processes. Moreover, recent advancements in animal and human models have provided valuable insights into how lithium-induced modifications at the homeostatic synaptic plasticity level may play a pivotal role in its clinical effectiveness. We focused on findings from translational studies suggesting that lithium may interface with microRNA expression. Finally, we are exploring the repurposing potential of lithium beyond bipolar disorder. These recent findings on the therapeutic mechanisms of lithium have provided important clues toward developing predictive models of response to lithium treatment and identifying new biologic targets. SIGNIFICANCE STATEMENT: Lithium is the drug of choice for the treatment of bipolar disorder, but its mechanism of action in stabilizing mood remains elusive. This review presents the latest evidence on lithium's various mechanisms of action. Recent evidence has strengthened glycogen synthase kinase-3 (GSK3) inhibition, changes at the level of homeostatic synaptic plasticity, and regulation of microRNA expression as key mechanisms, providing an intriguing perspective that may help bridge the mechanistic gap between molecular functions and its clinical efficacy as a mood stabilizer.

Association between abnormal brain oscillations and cognitive performance in patients with bipolar disorder; Molecular mechanisms and clinical evidence

Brain oscillations have gained great attention in neuroscience during recent decades as functional building blocks of cognitive-sensory processes. Research has shown that oscillations in "alpha," "beta," "gamma," "delta," and "theta" frequency windows are highly modified in brain pathology, including in patients with cognitive impairment like bipolar disorder (BD). The study of changes in brain oscillations can provide fundamental knowledge for exploring neurophysiological biomarkers in cognitive impairment. The present article reviews findings from the role and molecular basis of abnormal neural oscillation and synchronization in the symptoms of patients with BD. An overview of the results clearly demonstrates that, in cognitive-sensory processes, resting and evoked/event-related electroencephalogram (EEG) spectra in the delta, theta, alpha, beta, and gamma bands are abnormally changed in patients with BD showing psychotic features. Abnormal oscillations have been found to be associated with several neural dysfunctions and abnormalities contributing to BD, including abnormal GABAergic neurotransmission signaling, hippocampal cell discharge, abnormal hippocampal neurogenesis, impaired cadherin and synaptic contact-based cell adhesion processes, extended lateral ventricles, decreased prefrontal cortical gray matter, and decreased hippocampal volume. Mechanistically, impairment in calcium voltage-gated channel subunit alpha1 I, neurotrophic tyrosine receptor kinase proteins, genes involved in brain neurogenesis and synaptogenesis like WNT3 and ACTG2, genes involved in the cell adhesion process like CDH12 and DISC1, and gamma-aminobutyric acid (GABA) signaling have been reported as the main molecular contributors to the abnormalities in resting-state low-frequency oscillations in BD patients. Findings also showed the association of impaired synaptic connections and disrupted membrane potential with abnormal beta/gamma oscillatory activity in patients with BD. Of note, the synaptic GABA neurotransmitter has been found to be a fundamental requirement for the occurrence of long-distance synchronous gamma oscillations necessary for coordinating the activity of neural networks between various brain regions. This article is protected by copyright. All rights reserved.

Convergence between behavioral, neural, and self-report measures of cognitive control: The Frontal Systems Behavior Scale in bipolar disorder

The Frontal Systems Behavior Scale (FrSBe) is a self-report measure that assesses difficulties with cognitive and emotional control such as apathetic behavior, lack of inhibitory control, and executive dysfunction. Previous neuroimaging studies highlight the involvement of the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), and dorsolateral prefrontal cortex (DLPFC) in these processes. In this study, we investigated whether there was convergence across subjective and objective measures of apathy, disinhibition, and executive dysfunction. Specifically, we studied whether ACC, OFC, and DLPFC activation during a modified version of the Multi-Source Interference Task (MSIT), is associated with FrSBe apathy, disinhibition, and executive dysfunction scores, in healthy controls (HC) and individuals with Bipolar Disorder (BD), who commonly exhibit difficulties in these domains. Individuals with BD (n = 31) and HCs (n = 31) with no current or past psychiatric illness completed the FrSBe and the MSIT during fMRI scanning. We investigated task-specific changes in the ACC, DLPFC, and OFC and their correlations with FrSBe apathy, disinhibition, and executive dysfunction subscale scores, respectively. Individuals with BD and the HC group demonstrated greater ACC, DLPFC, and OFC activation during MSIT interference conditions compared with non-interference conditions. Furthermore, there was a significant negative correlation between OFC activation and disinhibition scores, which remained significant after accounting for medication load. Together, these results demonstrate the FrSBe disinhibition subscale, in particular, can be a self-report measure that converges with behavioral and neural markers of disinhibition in BD.

Characterizing mood disorders in the AFFECT study: a large, longitudinal, and phenotypically rich genetic cohort in the US

There has recently been marked progress in identifying genetic risk factors for major depression (MD) and bipolar disorder (BD); however, few systematic efforts have been made to elucidate heterogeneity that exists within and across these diagnostic taxa. The Affective disorders, Environment, and Cognitive Trait (AFFECT) study presents an opportunity to identify and associate the structure of cognition and symptom-level domains across the mood disorder spectrum in a prospective study from a diverse US population.Participants were recruited from the 23andMe, Inc research participant database and through social media; self-reported diagnosis of MD or BD by a medical professional and medication status data were used to enrich for mood-disorder cases. Remote assessments were used to acquire an extensive range of phenotypes, including mood state, transdiagnostic symptom severity, task-based measures of cognition, environmental exposures, personality traits. In this paper we describe the study design, and the demographic and clinical characteristics of the cohort. In addition we report genetic ancestry, SNP heritability, and genetic correlations with other large cohorts of mood disorders.A total of 48,467 participants were enrolled: 14,768 with MD, 9864 with BD, and 23,835 controls. Upon enrollment, 47% of participants with MD and 27% with BD indicated being in an active mood episode. Cases reported early ages of onset (mean = 13.2 and 14.3 years for MD and BD, respectively), and high levels of recurrence (78.6% and 84.9% with >5 episodes), psychotherapy, and psychotropic medication use. SNP heritability on the liability scale for the ascertained MD participants (0.19-0.21) was consistent with the high level of disease severity in this cohort, while BD heritability estimates (0.16-0.22) were comparable to reports in other large scale genomic studies of mood disorders. Genetic correlations between the AFFECT cohort and other large-scale cohorts were high for MD but not for BD. By incorporating transdiagnostic symptom assessments, repeated measures, and genomic data, the AFFECT study represents a unique resource for dissecting the structure of mood disorders across multiple levels of analysis. In addition, the fully remote nature of the study provides valuable insights for future virtual and decentralized clinical trials within mood disorders.

Web-Based Cognitive Testing in Psychiatric Research: Validation and Usability Study

Background

Cognitive impairments are features of many psychiatric disorders and affect functioning. A barrier to cognitive research on psychiatric disorders is the lack of large cross-disorder data sets. However, the collection of cognitive data can be logistically challenging and expensive. Web-based collection may be an alternative; however, little is known about who does and does not complete web-based cognitive assessments for psychiatric research.

Objective

The aims of this study are to develop a web-based cognitive battery for use in psychiatric research, validate the battery against the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery, and compare the characteristics of the participants who chose to take part with those of the individuals who did not participate.

Methods

Tasks were developed by The Many Brains Project and selected to measure the domains specified by the MATRICS initiative. We undertook a cross-validation study of 65 participants with schizophrenia, bipolar disorder, depression, or no history of psychiatric disorders to compare the web-based tasks with the MATRICS Consensus Cognitive Battery. Following validation, we invited participants from 2 large ongoing genetic studies, which recruited participants with psychiatric disorders to complete the battery and evaluated the demographic and clinical characteristics of those who took part.

Results

Correlations between web-based and MATRICS tasks ranged between 0.26 and 0.73. Of the 961 participants, 887 (92.3%) completed at least one web-based task, and 644 (67%) completed all tasks, indicating adequate completion rates. Predictors of web-based participation included being female (odds ratio [OR] 1.3, 95% CI 1.07-1.58), ethnicity other than White European (OR 0.66, 95% CI 0.46-0.96), higher levels of education (OR 1.19, 95% CI 1.11-1.29), diagnosis of an eating disorder (OR 2.17, 95% CI 1.17-4) or depression and anxiety (OR 5.12, 95% CI 3.38-7.83), and absence of a diagnosis of schizophrenia (OR 0.59, 95% CI 0.35-0.94). Lower performance on the battery was associated with poorer functioning (B=−1.76, SE 0.26; P<.001).

Conclusions

Our findings offer valuable insights into the advantages and disadvantages of testing cognitive function remotely for mental health research.

Obesity and overweight among children and adolescents with bipolar disorder from the general population: A review of the scientific literature and a meta-analysis

There is substantial evidence of the high prevalence of obesity (OB) and overweight (OW) and their association with increased medical and psychiatric burden among adults with bipolar disorder (BD). However, little is known regarding its prevalence among young people with BD, other than the risk from psychotropic medication, which has been the focus of research in this population. We present a systematic review and meta-analysis of the literature on prevalence and correlates of OB and OW children and adolescents with BD using a different perspective than impact of medication. Four studies met inclusion criteria. The prevalence of OB in children and adolescents with BD was 15% (95% CI 11-20%). We observed a higher prevalence of OB in comparison to the general population. Different studies found significant associations between OB, OW, and BD in young populations including non-Caucasian race, physical abuse, suicide attempts, self-injurious behaviours, psychotropic medication, and psychiatric hospitalizations.

Brain Derived Neurotrophic Factor and Cognitive Dysfunction in the Schizophrenia-Bipolar Spectrum: A Systematic Review and Meta-Analysis

BACKGROUND

Cognitive impairment is a core feature of disorders on the schizophrenia-bipolar spectrum, i.e., schizophrenia, bipolar disorder, and schizoaffective disorder. Brain-derived neurotrophic factor (BDNF) has been proposed to be a biomarker of cognitive impairment in these disorders as it plays a critical role in neuroplasticity and proposed to mediate some of the psychotropic effects of medication. However, despite numerous studies investigating the association between circulating BDNF and these disorders, no solid conclusions have been drawn regarding its involvement in cognitive impairment.

OBJECTIVES

The current systematic review and meta-analysis aims to examine blood BDNF levels and cognitive dysfunction in patients on the schizophrenia-bipolar spectrum as well as to evaluate whether circulating BDNF measurements can act as a biomarker for cognitive dysfunction.

METHODS

Studies were identified by searching Embase and Medline databases for English language articles published in peer-reviewed journals between 2000 January and 2021 June according to the PRISMA guidelines. A total of 815 articles were identified of which 32 met the inclusion criteria for the systematic review - reporting on comparisons between blood BDNF levels and cognitive functions of schizophrenia or bipolar disorder patients versus healthy controls (no studies involving schizoaffective patients were specifically obtained for the time being). Twenty-four of these studies (19 with schizophrenia and 5 with bipolar disorder patients) were eligible to be included in the meta-analysis.

RESULTS

Our findings indicated that circulating BDNF levels were significantly reduced in patients experiencing an acute episode of schizophrenia or bipolar disorder compared to healthy controls. Cognitive function was also found to be significantly worse in patients, however, correlations between BDNF levels and cognitive impairment were not always detected. Interventions, especially pharmacotherapy seemed to improve certain aspects of cognition and increase circulating BDNF levels.

CONCLUSION

Circulating BDNF alone does not seem to be a valid biomarker of cognitive dysfunction in patients with disorders on the schizophrenia-bipolar spectrum, owing to several confounding factors. Changes of the circulating levels of BDNF should be evaluated in a wider context of other stress-, immune-, and inflammatory-related factors.

Assessment Tool of Bipolar Disorder for Primary Health Care: The SAEBD

Mixed states are highly prevalent in patients with bipolar disorder and require comprehensive scales. Considering this, the current study aims to develop a measure to assess the full spectrum of clinical manifestations of bipolar disorder. A sample of 88 patients was evaluated; the Hamilton Depression Scale (HAM-D), Montgomery-Asberg Depression Scale (MADRS), and the Young Mania Rating Scale (YMRS) were applied, together with the preliminary version of the Scale for the Assessment of Episodes in Bipolar Disorder (SAEBD). After analyzing the appropriateness and statistical properties of the items, discriminant analysis and analysis of diagnostic capacity were performed. The discriminant functions correctly classified 100% of the cases in euthymia, predominant depressive symptoms or mixed symptoms, as well as 92.3% of the cases with predominant manic symptoms. Overall, the functions correctly classified 98.9% of the cases. The area under the curve (0.935) showed high capacity to discriminate between clinical and non-clinical cases (i.e., in euthymia). The SAEBD sensitivity was 0.95, specificity was 0.71, the Positive Predictive Value (PPV) was 0.88, the Negative Predictive Value (NPV) was 0.87, the Positive Likelihood Ratio (+LR) was 3.33, and the Negative Likelihood Ratio (−LR) was 0.07. In conclusion, the SAEBD is a promising scale that shows high reliability and validity, as well as diagnostic utility as a screening tool for use in diverse health care settings.

Do cognition and other person-level characteristics determine housing outcomes among homeless-experienced adults with serious mental illness?

Objective: Many persons with serious mental illness (SMI) who have experienced homelessness struggle to sustain stable and independent housing. We know little about determinants of this population's housing status. This study aimed to identify person-level determinants of housing status among homeless-experienced veterans with SMI, focused primarily on cognition. Method: We administered cross-sectional surveys and detailed cognitive assessments on a convenience sample of homeless-experienced veterans with SMI (n = 90); we also reviewed these participants' medical records. We captured person-level potential predictors of housing status (demographics, cognition, diagnoses, symptoms, and service utilization) and 2 years of retrospective housing history. Participants' housing status was conceptualized as the setting (stable housing, other sheltered settings, and streets) they lived in for >50% of the past 2 years. We used the chi-square test and analysis of variance to determine how potential predictors differed by housing status. We used recursive partitioning to identify the combination of potential predictors and corresponding scores that best-differentiated participants by housing status. Results: No between-groups differences (p < .05) in cognition, symptoms, or other person-level factors were found among participants grouped by housing status. Recursive partitioning did not yield a stable model to predict housing status from the potential predictor variables. Conclusions and Implications for Practice: These data suggest that clinical interventions addressing studied person-level factors (e.g., cognitive rehabilitation) may not affect housing status for homeless-experienced veterans. As housing is highly influenced by social determinants of health, policies, and practices that affect contextual factors (e.g., affordable housing supply) may be more likely to improve housing status. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cognitive complaints in individuals recently diagnosed with bipolar disorder: A cross-sectional study

AIM

To assess the differences in subjective cognitive dysfunction between major depressive disorder (MDD) and recently diagnosed Bipolar Disorder (BD) across euthymia and mood episodes.

METHODS

This is a cross-sectional study corresponding to the second wave of a longitudinal study. The first wave consisted of subjects aged between 18 and 60 diagnosed with MDD. In the follow up after three years (second wave), conversion from MDD to BD diagnosis was assessed by qualified psychologists using the Mini International Neuropsychiatric Interview (MINI-Plus). Subjects were categorized in four diagnostic groups: euthymic MDD, MDD in a current mood episode, euthymic BD, and BD in a current mood episode. All subjects completed the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA), an instrument specifically designed for detecting subjective cognitive deficits in BD.

RESULTS

The total sample (n = 468) included 410 subjects with MDD and 58 individuals recently diagnosed with BD. We subdivided the 2 groups based on their current mood state, and found a significant difference in COBRA total scores between euthymic BD individuals (median 17.00 [IQR: 8.75 - 20.75]) and euthymic MDD subjects (median 8.00 [IRQ: 5.00 - 14.00], p = 0.002), showing higher subjective cognitive dysfunction in individuals recently diagnosed with BD. The differences remained significant after adjusting for the presence of lifetime psychotic symptoms. We found no differences between MDD and BD during an acute mood episode.

LIMITATION

The small sample size of individuals with BD.

CONCLUSION

The findings suggest a higher presence of subjective cognitive complaints among individuals recently diagnosed with BD in comparison to individuals with MDD during euthymia.

Cognitive Impairment Among Tunisian Bipolar Patients: a Case-Control Study

Studies exploring the cognitive performance of bipolar patients have mainly been conducted in Western countries. To our knowledge, no surveys have been reported to date in Tunisia. The present work aimed to evaluate the cognitive functions, in the three domains of memory, attention and executive functions, among a sample of Tunisian individuals with bipolar disorder, during the remission period, compared to healthy control subjects. We found that Cognitive functions in euthymic patients with bipolar disorder were significantly more impaired than in controls, apart from the working memory that did not show a significant difference between the two groups. Our findings confirm cognitive deficits associated with bipolar disorder, even at a distance from the symptomatic phases of the disease. Thus, these anomalies may be considered as a trait marker of the disease. A better understanding of cognitive decline certainly allows for better management of psychiatric pathologies, thus improving patients' social skills and quality of life.

Neurostructural phenotypes of CACNA1C rs1006737 in adolescents with bipolar disorder and healthy controls

OBJECTIVE

Investigate the effects of CACNA1C rs1006737 on cortical and subcortical neurostructural phenotypes in Caucasian bipolar disorder (BD) and healthy control (HC) adolescents.

METHODS

Seventy-one adolescents (14-20 years; 38BD, 33HC) underwent 3-Tesla Magnetic Resonance Imaging (MRI). Region of interest (ROI) and vertex-wise analyses examined cortical volume, surface area (SA), and thickness, as well as subcortical volume. ROIs included the ventromedial prefrontal cortex (vmPFC), ventrolateral prefrontal cortex (vlPFC), anterior cingulate cortex (ACC), putamen, and amygdala. General linear models included main effects of diagnosis and rs1006737, and an interaction term, controlling for age, sex, and total intracranial volume.

RESULTS

Vertex-wise analysis found significant BD-by-rs1006737 interactions for prefrontal and occipital regions such that BD A-carriers were found to have greater SA relative to BD non-carriers, while HC A-carriers had reduced SA relative to HC non-carriers. ROI analysis found an interaction in the ACC such that BD A-carriers were found to have greater SA relative to BD non-carriers, while no significant difference was found in HCs. Main effects of rs1006737 were also found on ACC SA from ROI analysis, and occipital SA from vertex-wise analysis, such that A-carriers had larger SA relative to non-carriers in both of these regions.

CONCLUSIONS

The current study identified neurostructural intermediate phenotypes relevant to the impact of CACNA1C rs1006737 on adolescent BD. Further investigation is warranted into the neurofunctional and neurocognitive relevance of rs1006737 associations with BD-specific elevations in regional SA.

Neurocognitive Impairments (NCI) in bipolar disorder: Comparison with schizophrenia and healthy controls

BACKGROUND

Neurocognitive impairments (NCI) are common in patients with bipolar I disorder. However, reports about the affected domains, outcomes and magnitude have been inconsistent. The aim of this study was to compare the magnitude (severity) and specificity (domains), of (NCI) in euthymic Bipolar I Disorder (BD) patients with a demographically and educationally matched sample of patients with schizophrenia in remission (SC) and healthy controls (HC).

METHODS

The Screen for Cognitive Impairment in Psychiatry (SCIP) was applied in this cross-sectional study, to all consecutive and consenting euthymic outpatients with bipolar I disorder (BD) (n = 76), remitted patients with schizophrenia (n = 130) and age and gender-matched healthy controls (HC) (n = 100). The cognitive tests done included Verbal List Learning-Immediate (VLT-I), Working Memory Test (WMT), Verbal Fluency Test (VFT), Verbal Learning Test-Delayed (VLT-D) and Processing Speed Test (PST). Within the bipolar group, the association between NCI and functioning was assessed.

RESULTS

There was a significant difference in the proportions of participants that had cognitive impairment from the 3 groups (37% (HC) vs. 71.1% (BD) vs. 91.5%(SC) (p=<0.001). The BD group in comparison to the HCs did worse on all domains of the SCIP except WMT and PST. The BD group was not significantly different from the SC group in all neuropsychological domains of the SCIP except WMT. BD group significantly functions better than the SC group. The severity of depressive symptomatology and VLT-I were independent predictors of functioning in the BD group.

CONCLUSION

Cognitive impairment affects almost all the neurocognitive domains of the BD group. The difference in NCI between euthymic BD patients and SC in remission are quantitative rather than qualitative.

Pharmacokinetic and pharmacodynamic of the cognitive enhancer modafinil: Relevant clinical and forensic aspects

Modafinil is a nonamphetamine nootropic drug with an increasingly therapeutic interest due to its different sites of action and behavioral effects in comparison to cocaine or amphetamine. A review of modafinil (and of its prodrug adrafinil and its R-enantiomer armodafinil) chemical, pharmacokinetic, pharmacodynamic, toxicological, clinical and forensic aspects was performed, aiming to better understand possible health problems associated to its unconscious and unruled use. Modafinil is a racemate metabolized mainly in the liver into its inactive acid and sulfone metabolites, which undergo primarily renal excretion. Although not fully clarified, major effects seem to be associated to inhibition of dopamine reuptake and modulation of several other neurochemical pathways, namely noradrenergic, serotoninergic, orexinergic, histaminergic, glutamatergic and GABAergic. Due its wake-promoting effects, modafinil is used for the treatment of daily sleepiness associated to narcolepsy, obstructive sleep apnea and shift work sleep disorder. Its psychotropic and cognitive effects are also attractive in several other pathologies and conditions that affect sleep structure, induce fatigue and lethargy, and impair cognitive abilities. Additionally, in health subjects, including students, modafinil is being used off-label to overcome sleepiness, increase concentration and improve cognitive potential. The most common adverse effects associated to modafinil intake are headache, insomnia, anxiety, diarrhea, dry mouth and raise in blood pressure and heart rate. Infrequently, severe dermatologic effects in children, including maculopapular and morbilliform rash, erythema multiforme and Stevens-Johnson Syndrome have been reported. Intoxication and dependence associated to modafinil are uncommon. Further research on effects and health implications of modafinil and its analogs is steel needed to create evidence-based policies.

Neurocognitive impairment and evidence-based treatment options in Bipolar disorder

BACKGROUND

The current paper briefly summarizes the literature on the neurocognitive deficit and its treatment in BD patients.

METHODS

The material was chosen on the basis of previous systematic reviews the author has taken part in.

RESULTS

The data so far suggest that the deficit is qualitatively similar but quantitatively milder in comparison to schizophrenia, it is present already since the first episode, is weakly related to mood symptoms and somewhat stronger to psychotic symptoms, it probably determines much of the disability and treatment is problematic. This deficit is also present during periods of euthymia. The possible adverse effect of psychotropic medication is rather small if any at all and is confounded by the specific clinical symptoms, for which medication is used for their treatment. This is especially true concerning antipsychotics and psychotic symptoms. The origin and the etiopathogenesis of the core neurocognitive impairment remain elusive. The presence of a neurodegenerative and of a neurodevelopmental component has both data in favor and against and they are both the focus of debate.

CONCLUSIONS

Treatment of the neurocognitive deficit and restoration of functioning is problematic. The data are limited and treatment options are few and with a weak overall effect. Pharmacological treatments, ECT and rTMS present some hard data, while the literature is inconclusive concerning psychotherapeutic interventions.

FKBP5 Gene Variants May Modulate Depressive Features in Bipolar Disorder

BACKGROUND

Previous evidence suggested the possible association of FK506 binding protein 5 (FKBP5) gene variants in bipolar disorder (BPD).

OBJECTIVE

Given the need of refinement of the findings obtained in large but poorly phenotyped samples, this study investigated the possible role of variants within FKBP5 in a small but deeply phenotyped BPD sample.

METHODS

A sample (N = 131) of bipolar patients were investigated with 10 polymorphisms within the FKBP5 gene. A control sample (N = 65) was also used for the analyses. Treatment response and remission of symptoms were evaluated using of the Hamilton Depression Rating Scale (HDRS), Hamilton Anxiety Rating Scale (HARS), and Young Mania Rating Scale (YMRS). The same analyses were also performed on the depressive subsample of BPD (D.BPD).

RESULTS

rs3800373 was associated with disorder risk in the depressive BPD subsample with the G allele being more frequent in subjects with a D.BPD phenotype. This was the only association that survived statistical correction.

CONCLUSIONS

rs3800373 FKBP5 may increase the risk of developing predominantly depressed BPD, probably through the creation of an enhancer consensus sequence in the 3'UTR of the gene, thus potentially increasing its expression. This finding seems to be partially supported by literature data, which evidenced increased levels of FKBP5 in psychiatric subjects.

Identifying cognitive subgroups in bipolar disorder: A cluster analysis

BACKGROUND

Evidence has shown heterogeneity of cognitive function among patients with bipolar disorder (BD). Our study aims to replicate recent findings of cognitive subgroups, as well as we assessed subjective cognitive difficulties and functioning in each cluster.

METHODS

Hierarchical cluster analysis was conducted to examine whether there were distinct neurocognitive subgroups based on neurocognitive battery. Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) and Functioning Assessment Short Test (FAST) were used to assess subjective cognitive difficulties and functional impairment.

RESULTS

We found three distinct subgroups: a first cluster with intact cognition (n = 30, 43.5%), a second cluster with selective cognitive impairment (n = 23, 33.3%), and a third cluster with globally cognitive impairment (n = 16, 23.3%). The intact group had more years of education (p < .001) and higher estimated IQ (p < .001) than globally and selectively impaired subgroups. Additionally, they were younger (p = .011), had an earlier age at bipolar diagnosis (p < .037) and earlier age of first hospitalization (p < .035) compared to individuals with globally cognitive impairment.

LIMITATIONS

This is a cross-sectional design with a small sample including only patients from a tertiary hospital.

CONCLUSION

Our results give support to the existence of a continuum of severity from patients without impairment to those with poor cognitive functioning. Patients in the intact group seem to have higher cognitive reserve than other two groups. However, they also experienced cognitive complaints and some degree of functional impairment. These findings suggest the importance of using a combo of instruments (e.g., objective and subjective cognitive measures plus functioning instruments) for a complete assessment of patients with BD.

Bottom-up gamma and bipolar disorder, clinical and neuroepigenetic implications

OBJECTIVES

This limited review examines the role of the reticular activating system (RAS), especially the pedunculopontine nucleus (PPN), one site of origin of bottom-up gamma, in the symptoms of bipolar disorder (BD).

METHODS

The expression of neuronal calcium sensor protein 1 (NCS-1) in the brains of BD patients is increased. It has recently been found that all PPN neurons manifest intrinsic membrane beta/gamma frequency oscillations mediated by high threshold calcium channels, suggesting that it is one source of bottom-up gamma. This review specifically addresses the involvement of these channels in the manifestation of BD.

RESULTS

Excess NCS-1 was found to dampen gamma band oscillations in PPN neurons. Lithium, a first line treatment for BD, was found to decrease the effects of NCS-1 on gamma band oscillations in PPN neurons. Moreover, gamma band oscillations appear to epigenetically modulate gene transcription in PPN neurons, providing a new direction for research in BD.

CONCLUSIONS

This is an area needing much additional research, especially since the dysregulation of calcium channels may help explain many of the disorders of arousal in, elicit unwanted neuroepigenetic modulation in, and point to novel therapeutic avenues for, BD.

Effectiveness of smartphone-based ambulatory assessment (SBAA-BD) including a predicting system for upcoming episodes in the long-term treatment of patients with bipolar disorders: study protocol for a randomized controlled single-blind trial

BACKGROUND

The detection of early warning signs is essential in the long-term treatment of bipolar disorders. However, in bipolar patients' daily life and outpatient treatment the assessment of upcoming state changes faces several difficulties. In this trial, we examine the effectiveness of a smartphone based automated feedback about ambulatory assessed early warning signs in prolonging states of euthymia and therefore preventing hospitalization. This study aims to assess, whether patients experience longer episodes of euthymia, when their treating psychiatrists receive automated feedback about changes in communication and activity. With this additional information an intervention at an earlier stage in the development of mania or depression could be facilitated. We expect that the amount of time will be longer between affective episodes in the intervention group.

METHODS/DESIGN

The current study is designed as a randomized, multi-center, observer-blind, active-control, parallel group trial within a nationwide research project on the topic of innovative methods for diagnostics, prevention and interventions of bipolar disorders. One hundred and twenty patients with bipolar disorder will be randomly assigned to (1) the experimental group with included automated feedback or (2) the control group without feedback. During the intervention phase, the psychopathologic state of all participants is assessed every four weeks over 18 months. Kaplan-Meier estimators will be used for estimating the survival functions, a Log-Rank test will be used to formally compare time to a new episode across treatment groups. An intention-to-treat analysis will include data from all randomized patients.

DISCUSSION

This article describes the design of a clinical trial investigating the effectiveness of a smartphone-based feedback loop. This feedback loop is meant to elicit early interventions at the detection of warning signs for the prevention of affective episodes in bipolar patients. This approach will hopefully improve the chances of a timely intervention helping patients to keep a balanced mood for longer periods of time. In detail, if our hypothesis can be confirmed, clinical practice treating psychiatrists will be enabled to react quickly when changes are automatically detected. Therefore, outpatients would receive an even more individually tailored treatment concerning time and frequency of doctor's appointments.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT02782910 : Title: "Smartphone-based Ambulatory Assessment of Early Warning Signs (BipoLife_A3)". Registered May 25 2016. Protocol Amendment Number: 03. Issue Date: 26 March 2018. Author(s): ES.

Current Status of Cognitive Remediation for Psychiatric Disorders: A Review

Cognition is an important factor that affects daily functioning and quality of life. Impairment in cognitive function is a common symptom present in various psychological disorders, which hinders patients from functioning normally. Given that cognitive impairment has devastating effects, enhancing this in patients should lead to improvements in compromised quality of life and functioning, including vocational functioning. Over the past 50 years, several attempts have been made to improve impaired cognition, and empirical evidence for cognitive remediation (CR) has accumulated that supports its efficacy for treating schizophrenia. More recently, CR has been successfully applied in the treatment of depressive disorders, bipolar disorders, attention deficit/hyperactivity disorder, and anorexia nervosa. This study critically reviews recent CR studies and suggests their future direction. This study aimed to provide a modern definition of CR, and examine the current status of empirical evidence and representative CR programs that are widely used around the world.

Sex-specific effects of Cacna1c haploinsufficiency on object recognition, spatial memory, and reversal learning capabilities in rats

The CACNA1C gene is strongly implicated in the etiology of multiple major neuropsychiatric disorders, such as bipolar disorder, major depression, and schizophrenia, with cognitive deficits being a common feature. It is unclear, however, by which mechanisms CACNA1C variants advance the risk of developing neuropsychiatric disorders. This study set out to investigate cognitive functioning in a newly developed genetic Cacna1c rat model. Specifically, spatial and reversal learning, as well as object recognition memory were assessed in heterozygous Cacna1c^+/- rats and compared to wildtype Cacna1c^+/+ littermate controls in both sexes. Our results show that both Cacna1c^+/+ and Cacna1c^+/- animals were able to learn the rewarded arm configuration of a radial maze over the course of seven days. Both groups also showed reversal learning patterns indicative of intact abilities. In females, genotype differences were evident in the initial spatial learning phase, with Cacna1c^+/- females showing hypo-activity and fewer mixed errors. In males, a difference was found during probe trials for both learning phases, with Cacna1c^+/- rats displaying better distinction between previously baited and non-baited arms; and regarding cognitive flexibility in favor of the Cacna1c^+/+ animals. All experimental groups proved to be sensitive to reward magnitude and fully able to distinguish between novel and familiar objects in the novel object recognition task. Taken together, these results indicate that Cacna1c haploinsufficiency has a minor, but positive impact on (spatial) memory functions in rats.

[Neuropsychological Profile and Working Memory in Bipolar Disorder]

According to the World Health Organization (WHO), the bipolar disorder is one of the ten costliest and most incapacitating diseases in the world. Management of this pathology usually involves a psychiatric follow-up at a pace adapted to the thymic state, and the initiating of a mood-stabilizing treatment. However, what will become of patients with bipolar disorder remains unsatisfying. Psychosocial impacts, increased by often present physical and psychological comorbidities are important (Bonnin et al., 2010) and can be incapacitating: socioprofessional deintegration, social withdrawal, family-related repercussions, low socioeconomic status, lesser quality of life. A functional impairment is found in acute decompensation phases, but also in intercritical periods where different factors might be involved: thymic or cognitive residual symptomatology, as episode consequences, presence of comorbidities…Actually, in this stage of the disease, 30% of bipolar patients present cognitive impairments, that neuropsychological testing can objectify (Gualtieri and Morgan, 2008). Almost 2 thirds present subjective cognitive complaints (Martinez-Aran et al., 2005) that are negatively correlated with quality of life. Among these impairments, harm to working memory is reported in several studies (Bora et al., 2009; Robinson et al., 2006), and seems to play a leading role in functional impairment. Managing cognitive impairments seems an important issue to improve patient functioning, quality of life and disorder stability. However, cognitive remediation techniques, largely developed for patients with schizophrenia, remain limited in bipolar disorder, in spite of the great impact of cognitive impairments in this disorder. This objective of this article was an update on bipolar patient neuropsychological profile in an intercritical period, while putting forward working memory critical role in functional impairment. We will also discuss current therapeutic advances allowing to manage these impairments and improve patient functioning.

Gender differences in C-reactive protein and homocysteine modulation of cognitive performance and real-world functioning in bipolar disorder

BACKGROUND

Cognitive and psychosocial impairment has been associated with increased levels of C-reactive protein (CRP) and homocysteine in bipolar disorder, but gender differences have seldom been studied.

METHODS

Two hundred and twenty-four bipolar outpatients were included. Cognitive performance was assessed through the Screen for Cognitive Impairment in Psychiatry (SCIP). Psychosocial functioning was evaluated using the Functioning Assessment Short Test (FAST) and the General Assessment of Functioning (GAF). Homocysteine and CRP levels were determined. Separate analyses were performed by gender. Partial correlations were calculated to test for associations between biomarkers and cognitive and psychosocial functioning. Hierarchical multiple regression was used to assess factors predicting cognitive and psychosocial functioning. Covariates were: age, education, duration of illness, hospital admissions, depressive symptoms, tobacco consumption, and BMI.

RESULTS

A better performance was noted in women in delayed verbal learning (p = 0.010), along with better occupational functioning (p = 0.027) and greater leisure time impairment (p = 0.034). In men, CRP and homocysteine levels were associated with psychosocial dysfunction (interpersonal relationships and financial functioning, respectively). In women, CRP levels correlated with cognitive performance (SCIP total raw score, immediate and delayed verbal learning, and verbal fluency). CRP was a predictor of cognitive performance in women only.

LIMITATIONS

The choice of the cognitive scale and covariates and the lack of a control group may be the main limitations.

CONCLUSIONS

A gender difference was found in biomarker modulation of cognition and psychosocial functioning. A gender-based approach to cognition and real-world functioning should be considered in bipolar disorder to ensure an optimal outcome.

Cognitive function, treatment response to lithium, and social functioning in Japanese patients with bipolar disorder

OBJECTIVES

Patients with bipolar disorder often suffer from cognitive impairment that significantly influences their functional outcome. However, it remains unknown whether lithium has a central role in cognition and functional outcome. We examined whether cognition and functional outcome were predicted by demographic and clinical variables, including the response to lithium, in lithium-treated patients with bipolar disorder.

METHODS

We evaluated 96 lithium-treated euthymic patients with bipolar disorder and 196 age- and-gender-matched healthy controls, using the Brief Assessment of Cognition in Schizophrenia (BACS). The patients were also assessed using the Social Functioning Scale (SFS) and "The Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder" (Alda) scale, which was evaluated as either a continuous measure of the total scale or a dichotomous criterion.

RESULTS

Multiple regression analysis revealed two key findings: first, that the premorbid intelligence quotient, age, and number of mood episodes were predictors of the BACS composite score; and, second, that the BACS composite score, negative symptoms, and continuous measure on the total Alda scale (but not its dichotomy) predicted the total SFS score. Structural equation modeling (SEM) was used to confirm these findings, and additionally revealed that the Alda scale was significantly associated with negative symptoms and also the number of mood episodes, regardless of how it was evaluated.

CONCLUSIONS

SEM delineated how demographic and clinical variables, cognitive performance, and response to lithium treatment were causally associated with, and converged on, social function. The putative role of the Alda scale for social function warrants further study.

Clinical and treatment-related predictors of cognition in bipolar disorder: focus on visual paired associative learning

Bipolar disorder (BD) is associated with impairment in cognitive domains such as verbal memory and executive functions. However, visual paired associative learning (PAL) has been far less researched. Neurocognitive dysfunction in BD patients has been related to several clinical factors, but data on the effect of medication are relatively scarce and inconsistent. The aim of our study was to explore the effect of clinical and treatment-related parameters on executive functions and visual memory/learning, including PAL, in BD. Cognitive performance of 60 bipolar I patients and 30 healthy subjects was evaluated by using CANTAB battery tasks targeting spatial recognition memory, PAL and executive functions (set shifting, planning, inhibitory control). Bipolar patients showed poorer performance in PAL, set shifting, planning and inhibitory control than healthy subjects; however, only differences in PAL and planning survived correction for multiple comparisons. Number of previous manic episodes and illness duration predicted worse performance in set shifting and PAL, respectively, whereas current treatment with valproate predicted better performance in PAL. This is one of the first studies to assess clinical and treatment-related predictors of PAL in BD. We report a possibly beneficial effect of valproate on PAL, which warrants further investigation.

Validity and reliability of the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) in Japanese patients with bipolar disorder

In Japan, there are currently no reliable rating scales for the evaluation of subjective cognitive impairment in patients with bipolar disorder. We studied the relationship between the Japanese version of the Cognitive Complaints in Bipolar Disorder Rating Assessment (COBRA) and objective cognitive assessments in patients with bipolar disorder. We further assessed the reliability and validity of the COBRA. Forty-one patients, aged 16-64, in a remission period of bipolar disorder were recruited from Hokkaido University Hospital in Sapporo, Japan. The COBRA (Japanese version) and Frankfurt Complaint Questionnaire (FCQ), the gold standard in subjective cognitive assessment, were administered. A battery of neuropsychological tests was employed to measure objective cognitive impairment. Correlations among the COBRA, FCQ, and neuropsychological tests were determined using Spearman's correlation coefficient. The Japanese version of the COBRA had high internal consistency, good retest reliability, and concurrent validity-as indicated by a strong correlation with the FCQ. A significant correlation was also observed between the COBRA and objective cognitive measurements of processing speed. These findings are the first to demonstrate that the Japanese version of the COBRA may be clinically useful as a subjective cognitive impairment rating scale in Japanese patients with bipolar disorder.

Interaction between neuronal calcium sensor protein 1 and lithium in pedunculopontine neurons

Bipolar disorder is characterized by sleep dysregulation, suggesting a role for the reticular activating system (RAS). Postmortem studies showed increased expression of neuronal calcium sensor protein 1 (NCS-1) in the brains of some bipolar disorder patients, and reduced or aberrant gamma band activity is present in the same disorder. Lithium (Li+) has been shown to effectively treat the mood disturbances in bipolar disorder patients. We previously showed that NCS-1 at low levels increased, and at high levels decreased, gamma oscillations in RAS pedunculopontine neurons (PPN), and that Li+ decreased these oscillations. We previously described the effects of each agent on oscillations, G-protein mechanisms, and Ca2+ currents. However, we designed the present experiments to determine the nature of the interaction of NCS-1 and Li+ at physiological concentrations that would have an effect within minutes of application. As expected, Li+ decreased gamma oscillation amplitude, while NCS-1 increased the amplitude of gamma oscillations. We identified NCS-1 at 2 μmol/L as a concentration that increased gamma oscillations within 5-10 min, and Li+ at 10 μmol/L as a concentration that decreased gamma oscillations within 5 min. The combined application of NCS-1 and Li+ at these concentrations showed that Li+ reduced the effects of NCS-1 on oscillation amplitude within 5-10 min. These results demonstrate that at physiological levels, Li+ acts to reduce the effects of NCS-1 so that, given over expression of NCS-1, Li+ would have salutary effects.

Controlled Study of Obesity Among Adolescents with Bipolar Disorder

OBJECTIVE

Despite numerous studies regarding obesity (OB) in adult bipolar disorder (BP), there are few studies on this topic among adolescents. The current study attempts to extend the literature on prevalence and correlates of OB in adolescent BP by including control participants, and determining OB by direct measurement.

METHODS

Participants were 75 treatment-seeking adolescents, ages 13-19 years, with BP-I, -II, or -not otherwise specified, and 47 adolescents without major psychiatric illness. Diagnoses and clinical characteristics were assessed using the Kiddie Schedule for Affective Disorders and Schizophrenia for School Age Children, Present and Lifetime version (KSADS-PL). Family psychiatric history was assessed using the Family History Screen. OB was defined as adjusted body-mass index ≥95th percentile. Variables associated with OB in univariate analyses informed variable selection for within-group logistic regression analysis among BP adolescents.

RESULTS

BP participants had a significantly higher rate of OB (18%) compared to controls (4%; χ² = 5.3; p = 0.02). BP remained a significant predictor for OB when controlling for race (odds ratio [OR] = 5.1, 95% confidence interval [CI] = 1.1-24.0, p = 0.04). In univariate analyses among BP adolescents, OB was significantly associated with suicide attempt, self-injurious behavior, and oppositional defiant disorder. In multivariable analyses, suicide attempt and antidepressants that were not selective serotonin reuptake inhibitors were significantly associated with OB.

CONCLUSIONS

OB is excessively prevalent among adolescents with BP and is associated with proxies for illness severity, including suicide attempts. Additional research is warranted to identify strategies to prevent and treat OB among BP adolescents, and to elucidate processes underlying the elevated risk of suicide attempts.

The International College of Neuro-Psychopharmacology (CINP) Treatment Guidelines for Bipolar Disorder in Adults (CINP-BD-2017), Part 2: Review, Grading of the Evidence, and a Precise Algorithm

Background

The current paper includes a systematic search of the literature, a detailed presentation of the results, and a grading of treatment options in terms of efficacy and tolerability/safety.

Material and Methods

The PRISMA method was used in the literature search with the combination of the words 'bipolar,' 'manic,' 'mania,' 'manic depression,' and 'manic depressive' with 'randomized,' and 'algorithms' with 'mania,' 'manic,' 'bipolar,' 'manic-depressive,' or 'manic depression.' Relevant web pages and review articles were also reviewed.

Results

The current report is based on the analysis of 57 guideline papers and 531 published papers related to RCTs, reviews, posthoc, or meta-analysis papers to March 25, 2016. The specific treatment options for acute mania, mixed episodes, acute bipolar depression, maintenance phase, psychotic and mixed features, anxiety, and rapid cycling were evaluated with regards to efficacy. Existing treatment guidelines were also reviewed. Finally, Tables reflecting efficacy and recommendation levels were created that led to the development of a precise algorithm that still has to prove its feasibility in everyday clinical practice.

Conclusions

A systematic literature search was conducted on the pharmacological treatment of bipolar disorder to identify all relevant random controlled trials pertaining to all aspects of bipolar disorder and graded the data according to a predetermined method to develop a precise treatment algorithm for management of various phases of bipolar disorder. It is important to note that the some of the recommendations in the treatment algorithm were based on the secondary outcome data from posthoc analyses.

The Five-Choice Continuous Performance Task (5C-CPT): A Cross-Species Relevant Paradigm for Assessment of Vigilance and Response Inhibition in Rodents

Deficits in the domains of attention and response inhibition are central to many psychiatric disorders. As such, animal models of disorders purporting to replicate these behavioral deficits first require tests that can accurately assess the behaviors with high fidelity. The gold-standard clinical test of attention and response inhibition is the continuous performance test (CPT). Although there are a number of CPTs, all share the premise of responding to target stimuli and inhibiting from responding to non-target stimuli. The recently developed rodent five-choice CPT (5C-CPT) requires similar behavioral responses, enabling signal detection parameter calculations. With demonstrable feasibility for rodent testing, the 5C-CPT permits/facilitates: (1) delineation of neural mechanisms underlying these behaviors; (2) multifactorial analyses of the complex interplay between genetic and environmental manipulations relevant to psychiatric disorders; and hence (3) development of novel targeted treatments. All data to date indicate that the rodent 5C-CPT described here has direct translatability to clinical CPTs, producing equivalent measures of behavior in experimental animals to those assessed in humans. The 5C-CPT task provides an important tool toward delineating these mechanisms and developing treatments. However, it is also complex, with long training times and nuances requiring a thorough understanding before utilization. This unit will enable researchers to avoid potential missteps, greatly increasing the likelihood of success. © 2017 by John Wiley & Sons, Inc.

Role of calcium channels in bipolar disorder

Bipolar disorder is characterized by a host of sleep-wake abnormalities that suggests that the reticular activating system (RAS) is involved in these symptoms. One of the signs of the disease is a decrease in high frequency gamma band activity, which accounts for a number of additional deficits. Bipolar disorder has also been found to overexpress neuronal calcium sensor protein 1 (NCS-1). Recent studies showed that elements in the RAS generate gamma band activity that is mediated by high threshold calcium (Ca2+) channels. This mini-review provides a description of recent findings on the role of Ca2+ and Ca2+ channels in bipolar disorder, emphasizing the involvement of arousal-related systems in the manifestation of many of the disease symptoms. This will hopefully bring attention to a much-needed area of research and provide novel avenues for therapeutic development.

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.

A preliminary longitudinal study on the cognitive and functional outcome of bipolar excellent lithium responders

BACKGROUND

Neurocognitive dysfunction in bipolar disorder represents a possible marker of underlying pathophysiology, but to date, most studies are cross-sectional and heterogeneous with regard to pharmacological treatments. In the present study we investigated the 6-year cognitive and functional outcome of a sample of euthymic excellent lithium responders (ELR).

METHOD

A total sample of twenty subjects was assessed at baseline and 6years later: ten diagnosed of bipolar disorder according to DSM-IV criteria and ten healthy matched controls. The sample size was enough to find statistical differences between groups, with a statistical power of 0.8. Bipolar patients were on lithium treatment during all this follow-up period and fulfilled ELR criteria as measured by the Alda scale. A neuropsychological test battery tapping into the main cognitive domains was used at baseline and at after 6-year of follow-up. Functional outcome was evaluated by means of the Functioning Assessment Short Test at study endpoint.

RESULTS

Repeated measures multivariate analyses of variance showed that bipolar patients were cognitively impaired in the executive functioning, inhibition, processing speed and verbal memory domains (p<0.03) compared to controls and such deficits were stable over time. Longer duration of illness and lower psychosocial outcome were significantly related to cognitive impairment (p<0.05).

CONCLUSIONS

Cognitive dysfunction was present even in euthymic ELR. These deficits remain stable over the long term, and are basically associated with greater symptoms and poorer psychosocial adjustment.

Stress and reward processing in bipolar disorder: a functional magnetic resonance imaging study

OBJECTIVES

A link between negative life stress and the onset of mood episodes in bipolar disorder (BD) has been established, but processes underlying such a link remain unclear. Growing evidence suggests that stress can negatively affect reward processing and related neurobiological substrates, indicating that a dysregulated reward system may provide a partial explanation. The aim of this study was to test the impact of stress on reward-related neural functioning in BD.

METHODS

Thirteen euthymic or mildly depressed individuals with BD and 15 controls performed a Monetary Incentive Delay (MID) task while undergoing functional magnetic resonance imaging during no-stress and stress (negative psychosocial stressor involving poor performance feedback and threat of monetary deductions) conditions.

RESULTS

In hypothesis-driven region-of-interest analyses, a significant group-by-condition interaction emerged in the amygdala during reward anticipation. Relative to controls, while anticipating a potential reward, subjects with BD were characterized by amygdalar hyperactivation in the no-stress condition but hypoactivation during stress. Moreover, relative to controls, subjects with BD had significantly larger amygdala volumes. After controlling for structural differences, the effects of stress on amygdalar function remained, whereas groups no longer differed during the no-stress condition. During reward consumption, a group-by-condition interaction emerged in the putamen due to increased putamen activation in response to rewards in participants with BD during stress, but an opposite pattern in controls.

CONCLUSIONS

Overall, findings highlight possible impairments in using reward-predicting cues to adaptively engage in goal-directed actions in BD, combined with stress-induced hypersensitivity to reward consumption. Potential clinical implications are discussed.

Increased Beta Frequency (15-30 Hz) Oscillatory Responses in Euthymic Bipolar Patients Under Lithium Monotherapy

The effect of lithium on neurocognition is not still fully explored. Brain oscillatory activity is altered in bipolar disorder. We aimed to assess the oscillatory responses of euthymic bipolar patients and how they are affected by lithium monotherapy. Event-related oscillations in response to visual target stimulus during an oddball paradigm in 16 euthymic drug-free and 13 euthymic lithium-treated bipolar patients were compared with 16 healthy controls. The maximum peak-to-peak amplitudes were measured for each subject's averaged beta (15-30 Hz) responses in the 0- to 300-ms time window over frontal (F3, Fz, F4), central (C3, Cz, C4), temporal (T7, T8), temporo-parietal (TP7, TP8), parietal (P3, Pz, P4), and occipital (O1, Oz, O2) areas. Patients under lithium monotherapy had significantly higher beta responses to visual target stimuli than healthy controls (P=.017) and drug-free patients (P=.015). The increase in beta response was observed at all electrode locations, however, the difference was statistically significant for the left (T7; P=.016) and right (T8; P=.031) temporal beta responses. Increased beta responses in drug-free patients and further significant increase in lithium-treated patients may be indicative of a core pathophysiological process of bipolar disorder and how it is affected by lithium. Whether the finding corresponds to lithium's corrective effect on the underlying pathology or to its neurocognitive side effect remains to be further explored. In either case, the finding is a sign that the oscillatory activity may be useful in tracking medication effect in bipolar disorder.

The TLX-miR-219 cascade regulates neural stem cell proliferation in neurodevelopment and schizophrenia iPSC model

Dysregulated expression of miR-219, a brain-specific microRNA, has been observed in neurodevelopmental disorders, such as schizophrenia (SCZ). However, its role in normal mammalian neural stem cells (NSCs) and in SCZ pathogenesis remains unknown. We show here that the nuclear receptor TLX, an essential regulator of NSC proliferation and self-renewal, inhibits miR-219 processing. miR-219 suppresses mouse NSC proliferation downstream of TLX. Moreover, we demonstrate upregulation of miR-219 and downregulation of TLX expression in NSCs derived from SCZ patient iPSCs and DISC1-mutant isogenic iPSCs. SCZ NSCs exhibit reduced cell proliferation. Overexpression of TLX or inhibition of miR-219 action rescues the proliferative defect in SCZ NSCs. Therefore, this study uncovers an important role for TLX and miR-219 in both normal neurodevelopment and in SCZ patient iPSC-derived NSCs. Moreover, this study reveals an unexpected role for TLX in regulating microRNA processing, independent of its well-characterized role in transcriptional regulation.

Dysregulation of microRNAs has been implicated in neurodevelopmental disorders, including schizophrenia. Here the authors show that the TLX-miR-219 cascade regulates the proliferation of neural stem cells during normal development, and this pathway is dysregulated in a schizophrenia iPSC model.

Lithium decreases the effects of neuronal calcium sensor protein 1 in pedunculopontine neurons

Human postmortem studies reported increased expression of neuronal calcium sensor protein 1 (NCS-1) in the brains of some bipolar disorder patients, and reduced or aberrant gamma band activity is present in the same disorder. Bipolar disorder is characterized by sleep dysregulation, suggesting a role for the reticular activating system (RAS). Lithium (Li(+)) has been shown to effectively treat the mood disturbances in bipolar disorder patients and was proposed to act by inhibiting the interaction betweenNCS-1 and inositol 1,4,5-triphosphate receptor protein (InsP3R).NCS-1 is known to enhance the activity of InsP3R, and of Ca(2+)-mediated gamma oscillatory activity in the pedunculopontine nucleus (PPN), part of theRAS This study aimed to determine the nature of some of the intracellular mechanisms of Li(+)on ratPPNcells and to identify the interaction between Li(+)andNCS-1. Since Li(+)has been shown to act by inhibiting the enhancing effects ofNCS-1, we tested the hypothesis that Li(+)would reduced the effects of overexpression ofNCS-1 and prevent the downregulation of gamma band activity. Li(+)decreased gamma oscillation frequency and amplitude by downregulating Ca(2+)channel activity, whereasNCS-1 reduced the effect of Li(+)on Ca(2+)currents. These effects were mediated by a G-protein overinhibition of Ca(2+)currents. These results suggest that Li(+)affected intracellular pathways involving the activation of voltage-gated Ca(2+)channels mediated by an intracellular mechanism involving voltage-dependent activation of G proteins, thereby normalizing gamma band oscillations mediated by P/Q-type calcium channels modulated byNCS-1.

Comparative neurocognitive effects of lithium and anticonvulsants in long-term stable bipolar patients

BACKGROUND

The aim of choosing a mood-stabilizing drug (lithium or anticonvulsants) or a combination of them with minimal neurocognitive effects is to stimulate the development of criteria for a therapeutic adequacy, particularly in Bipolar Disorder (BD) patients who are clinically stabilized.

METHOD

Three groups of BD patients were established according to their treatment: (i) lithium monotherapy (n=29); (ii) lithium together with one or more anticonvulsants (n=28); and (iii) one or more anticonvulsants (n=16). A group of healthy controls served as the control (n=25). The following tests were applied: Wechsler Adult Intelligence Scale, Trail Making Test, Wechsler Memory Scale, Rey Complex Figure Test, Stroop color-word test, Wisconsin Card Sorting Test, Tower of Hanoi, Frontal Assessment Battery, and Reading the Mind in the Eyes Test.

RESULTS

Relative to healthy controls, BD patients showed the following: (i) those on lithium monotherapy, but not other BD groups, had preserved short-term auditory memory, long-term memory, and attention; (ii) those who took only anticonvulsants showed worse findings in short-term visual memory, working memory, and several executive functions; and (iii) all BD patients showed worse performance in processing speed, resistance to interference, and emotion recognition.

LIMITATIONS

Medication alone cannot explain why all BD patients showed common cognitive deficits despite different pharmacological treatment.

CONCLUSION

The impairment on some executive functions and emotion recognition is an inherent trait in BD patients, regardless of their pharmacological treatment. However, while memory, attention, and most of the executive functions are preserved in long-term stable BD patients, these cognitive functions are impaired in those who take anticonvulsants.

Optimising screening for cognitive dysfunction in bipolar disorder: Validation and evaluation of objective and subjective tools

INTRODUCTION

Cognitive impairment is common in bipolar disorder and contributes to socio-occupational difficulties. The objective was to validate and evaluate instruments to screen for and monitor cognitive impairments, and improve the understanding of the association between cognitive measures and socio-occupational capacity.

METHODS

Patients with bipolar disorder in partial or full remission (n=84) and healthy controls (n=68) were assessed with the Screen for Cognitive Impairment in Psychiatry (SCIP), Cognitive Complaints in Bipolar Disorder Rating Scale (COBRA), and established neuropsychological tests and subjective rating scales. Socio-occupational function and affective symptoms were evaluated with the Functional Assessment Short Test, and the Hamilton Depression Rating Scale 17-items and Young Mania Rating Scale, respectively. Concurrent validity of the SCIP and COBRA were assessed by correlation with established objective and subjective cognitive measures, and decision validity was determined with Receiver-Operating-Characteristic analyses. Correlations and linear regression analyses were conducted to determine the associations between objective and subjective cognitive impairment, and socio-occupational difficulties.

RESULTS

The SCIP and COBRA correlated strongly with established objective and subjective cognitive measures, respectively. The SCIP yielded higher sensitivity and specificity for detection of cognitive dysfunction than the COBRA or a combined SCIP-COBRA measure. Correlations between objective and subjective cognitive impairment were weak but both were associated with socio-occupational difficulties.

LIMITATIONS

Influence of ageing was not investigated.

CONCLUSIONS

The SCIP and COBRA are valid for detection of objective and subjective cognitive impairment in bipolar disorder. Screening for cognitive dysfunction should be conducted with an objective measure like the SCIP.

A report on older-age bipolar disorder from the International Society for Bipolar Disorders Task Force

OBJECTIVES

In the coming generation, older adults with bipolar disorder (BD) will increase in absolute numbers as well as proportion of the general population. This is the first report of the International Society for Bipolar Disorder (ISBD) Task Force on Older-Age Bipolar Disorder (OABD).

METHODS

This task force report addresses the unique aspects of OABD including epidemiology and clinical features, neuropathology and biomarkers, physical health, cognition, and care approaches.

RESULTS

The report describes an expert consensus summary on OABD that is intended to advance the care of patients, and shed light on issues of relevance to BD research across the lifespan. Although there is still a dearth of research and health efforts focused on older adults with BD, emerging data have brought some answers, innovative questions, and novel perspectives related to the notion of late onset, medical comorbidity, and the vexing issue of cognitive impairment and decline.

CONCLUSIONS

Improving our understanding of the biological, clinical, and social underpinnings relevant to OABD is an indispensable step in building a complete map of BD across the lifespan.

Assessment of subjective and objective cognitive function in bipolar disorder: Correlations, predictors and the relation to psychosocial function

Cognitive dysfunction is prevalent in bipolar disorder (BD). However, the evidence regarding the association between subjective cognitive complaints, objective cognitive performance and psychosocial function is sparse and inconsistent. Seventy seven patients with bipolar disorder who presented cognitive complaints underwent assessment of objective and subjective cognitive function and psychosocial functioning as part of their participation in two clinical trials. We investigated the association between global and domain-specific objective and subjective cognitive function and between global cognitive function and psychosocial function. We also identified clinical variables that predicted objective and subjective cognitive function and psychosocial functioning. There was a correlation between global subjective and objective measures of cognitive dysfunction but not within the individual cognitive domains. However, the correlation was weak, suggesting that cognitive complaints are not an assay of cognition per se. Self-rated psychosocial difficulties were associated with subjective (but not objective) cognitive impairment and both subjective cognitive and psychosocial difficulties were predicted by depressive symptoms. Our findings indicate that adequate assessment of cognition in the clinical treatment of BD and in drug trials targeting cognition requires implementation of not only subjective measures but also of objective neuropsychological tests.

Connectome signatures of neurocognitive abnormalities in euthymic bipolar I disorder

OBJECTIVES

Connectomics have allowed researchers to study integrative patterns of neural connectivity in humans. Yet, it is unclear how connectomics may elucidate structure-function relationships in bipolar I disorder (BPI). Expanding on our previous structural connectome study, here we used an overlapping sample with additional psychometric and fMRI data to relate structural connectome properties to both fMRI signals and cognitive performance.

METHODS

42 subjects completed a neuropsychological (NP) battery covering domains of processing speed, verbal memory, working memory, and cognitive flexibility. 32 subjects also had fMRI data performing a Go/NoGo task.

RESULTS

Bipolar participants had lower NP performance across all domains, but only working memory reached statistical significance. In BPI participants, processing speed was significantly associated with both white matter integrity (WMI) in the corpus callosum and interhemispheric network integration. Mediation models further revealed that the relationship between interhemispheric integration and processing speed was mediated by WMI, and processing speed mediated the relationship between WMI and working memory. Bipolar subjects had significantly decreased BA47 activation during NoGo vs. Go. Significant predictors of BA47 fMRI activations during the Go/NoGo task were its nodal path length (left hemisphere) and its nodal clustering coefficient (right hemisphere).

CONCLUSIONS

This study suggests that structural connectome changes underlie abnormalities in fMRI activation and cognitive performance in euthymic BPI subjects. Results support that BA47 structural connectome changes may be a trait marker for BPI. Future studies are needed to determine if these "connectome signatures" may also confer a biological risk and/or serve as predictors of relapse.

Effects of Short-Term Cognitive Remediation on Cognitive Dysfunction in Partially or Fully Remitted Individuals with Bipolar Disorder: Results of a Randomised Controlled Trial

INTRODUCTION

Cognitive dysfunction is common in bipolar disorder (BD) but is not sufficiently addressed by current treatments. Cognitive remediation (CR) may improve cognitive function in schizophrenia but no randomised controlled trial has investigated this intervention in BD. The present study aimed to investigate the effects of CR on persistent cognitive dysfunction in BD.

METHOD

Patients with BD in partial remission with cognitive complaints were randomised to 12 weeks group-based CR (n=23) or standard treatment (ST) (n=23). Outcomes were improved verbal memory (primary), sustained attention, executive and psychosocial function (secondary) and additional measures of cognitive and psychosocial function (tertiary). Participants were assessed at baseline and weeks 12 and 26.

RESULTS

Of the 46 randomised participants five dropped out and one was excluded after baseline. CR (n=18) had no effect on primary or secondary measures of cognitive or psychosocial function compared with ST (n=22). However, CR improved subjective sharpness at week 12, and quality of life and verbal fluency at week 26 follow-up (tertiary outcomes). Although the trial turned out to have suboptimal statistical power for the primary outcome analysis, calculation of the 95% confidence interval showed that it was highly unlikely that an increase in sample size would have rendered any beneficial effects of CR vs. ST on the verbal memory.

CONCLUSIONS

Short-term group-based CR did not seem to improve overall cognitive or psychosocial function in individuals with BD in full or partial remission. The present findings suggest that that longer-term, more intensive and individualised CR may be necessary to improve cognition in BD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01457235.

Low-dose add-on memantine treatment may improve cognitive performance and self-reported health conditions in opioid-dependent patients undergoing methadone-maintenance-therapy

An important interaction between opioid and dopamine systems has been indicated, and using opioids may negatively affect cognitive functioning. Memantine, a medication for Alzheimer's disease, increasingly is being used for several disorders and maybe important for cognitive improvement. Opioid-dependent patients undergoing methadone-maintenance-therapy (MMT) and healthy controls (HCs) were recruited. Patients randomly assigned to the experimental (5 mg/day memantine (MMT+M) or placebo (MMT+P) group: 57 in MMT+M, 77 in MMT+P. Those completed the cognitive tasks at the baseline and after the 12-week treatment were analyzed. Thirty-seven age- and gender-matched HCs, and 42 MMT+P and 39 MMT+M patients were compared. The dropout rates were 49.4% in the MMT+P and 26.3% in the MMT+M. Both patient groups' cognitive performances were significantly worse than that of the HCs. After the treatment, both patient groups showed improved cognitive performance. We also found an interaction between the patient groups and time which indicated that the MMT+M group's post-treatment improvement was better than that of the MMT+P group. Memantine, previously reported as neuroprotective may attenuate chronic opioid-dependence-induced cognitive decline. Using such low dose of memantine as adjuvant treatment for improving cognitive performance in opioid dependents; the dose of memantine might be a worthy topic in future studies.