Neurocognitive profiles in bipolar I and bipolar II disorder: differences in pattern and magnitude of dysfunction

Violent Offending in Males With or Without Schizophrenia: A Role for Social Cognition?

BACKGROUND AND HYPOTHESIS

Reduced social cognition has been reported in individuals who have committed interpersonal violence. It is unclear if individuals with schizophrenia and a history of violence have larger impairments than violent individuals without psychosis and non-violent individuals with schizophrenia. We examined social cognition in two groups with violent offenses, comparing their performance to non-violent individuals with schizophrenia and healthy controls.

STUDY DESIGN

Two social cognitive domains were assessed in four groups: men with a schizophrenia spectrum disorder with (SSD-V, n = 27) or without (SSD-NV, n = 42) a history of violence, incarcerated men serving preventive detention sentences (V, n = 22), and healthy male controls (HC, n = 76). Theory of mind (ToM) was measured with the Movie for the Assessment of Social Cognition (MASC), body emotion perception with Emotion in Biological Motion (EmoBio) test.

STUDY RESULTS

Kruskal-Wallis H-tests revealed overall group differences for social cognition. SSD-V had a global and clinically significant social cognitive impairment. V had a specific impairment, for ToM. Binary logistic regressions predicting violence category membership from social cognition and psychosis (SSD status) were conducted. The model with best fit, explaining 18%-25% of the variance, had ToM as the only predictor.

CONCLUSIONS

Social cognitive impairment was present in individuals with a history of violence, with larger and more widespread impairment seen in schizophrenia. ToM predicted violence category membership, psychosis did not. The results suggest a role for social cognition in understanding interpersonal violence.

Clinical neuropsychological characteristics of bipolar disorder, with a focus on cognitive and linguistic pattern: a conceptual analysis

Neuropsychology is an academic discipline that investigates the intricate interplay between the brain, mind, and behavior. It accomplishes this by examining the underlying structure and activities of the brain, with a particular focus on psychological phenomena such as language, motivation, memory, attention, thinking, consciousness, learning, and efficacy. The assessment of neuropsychological changes in individuals diagnosed with bipolar disorder has received limited attention in comparison to other psychiatric conditions, such as schizophrenia, for instance. Nevertheless, there has been a growing interest in the etiological implications, therapies, preventions, and prognostic factors related to social competence and the quality of life of patients. The objective of this review is to compile and analyze the existing research conducted thus far on the association between cognitive abnormalities and bipolar disorder. This study has examined research conducted across many stages of the condition, including depression and mania. Additionally, it has explored comparative studies involving people with schizophrenia, as well as the potential impact of psychopharmaceutical interventions.

Status of Type II vs. Type I Bipolar Disorder: Systematic Review with Meta-Analyses

LEARNING OBJECTIVES AFTER PARTICIPATING IN THIS CME ACTIVITY, THE PSYCHIATRIST SHOULD BE BETTER ABLE TO

• Analyze and compare the different bipolar disorder (BD) types.• Identify markers that distinguish BD types and explain how the DSM-IV defines the disorder.

ABSTRACT

Since the status of type II bipolar disorder (BD2) as a separate and distinct form of bipolar disorder (BD) remains controversial, we reviewed studies that directly compare BD2 to type I bipolar disorder (BD1). Systematic literature searching yielded 36 reports with head-to-head comparisons involving 52,631 BD1 and 37,363 BD2 patients (total N = 89,994) observed for 14.6 years, regarding 21 factors (with 12 reports/factor). BD2 subjects had significantly more additional psychiatric diagnoses, depressions/year, rapid cycling, family psychiatric history, female sex, and antidepressant treatment, but less treatment with lithium or antipsychotics, fewer hospitalizations or psychotic features, and lower unemployment rates than BD1 subjects. However, the diagnostic groups did not differ significantly in education, onset age, marital status, [hypo]manias/year, risk of suicide attempts, substance use disorders, medical comorbidities, or access to psychotherapy. Heterogeneity in reported comparisons of BD2 and BD1 limits the firmness of some observations, but study findings indicate that the BD types differ substantially by several descriptive and clinical measures and that BD2 remains diagnostically stable over many years. We conclude that BD2 requires better clinical recognition and significantly more research aimed at optimizing its treatment.

Mitochondria dysfunction and bipolar disorder: From pathology to therapy

Bipolar disorder (BD) is one of the major psychiatric diseases in which the impairment of mitochondrial functions has been closely connected or associated with the disease pathologies. Different lines of evidence of the close connection between mitochondria dysfunction and BD were discussed with a particular focus on (1) dysregulation of energy metabolism, (2) effect of genetic variants, (3) oxidative stress, cell death and apoptosis, (4) dysregulated calcium homeostasis and electrophysiology, and (5) current as well as potential treatments targeting at restoring mitochondrial functions. Currently, pharmacological interventions generally provide limited efficacy in preventing relapses or recovery from mania or depression episodes. Thus, understanding mitochondrial pathology in BD will lead to novel agents targeting mitochondrial dysfunction and formulating new effective therapy for BD.

Correlation between cognitive performance and structural neuroanatomy in patients with type I bipolar affective disorder treated with and without lithium

INTRODUCTION

Lithium treatment of bipolar disorder (BD) has been associated with less cognitive impairment and fewer changes in structural brain anatomy compared to other treatments. However, the studies are heterogeneous and few assess whether these effects are related. The objective of this study was to evaluate and relate cognitive performance and structural neuroanatomy in patients treated with and without lithium.

METHODS

Cross-sectional study that included 48 subjects with BD-I, of which 22 were treated with lithium and 26 without lithium. Performance was assessed on Wechsler III (WAIS III), TMT A and B (Trial Making Test) neuropsychological tests, California verbal learning test (CVLT), Rey complex figure test and Wisconsin card sorting test. Brain structures obtained by magnetic resonance imaging (MRI) were evaluated. The standardised mean difference (SMD) between both groups was calculated, adjusted for confounding variables using a propensity score, and the Spearman correlation coefficient (ρ) was used to assess the relationship between cognitive performance and neuroanatomical regions.

RESULTS

Compared to the group without lithium, the group with lithium had fewer perseverative errors in the Wisconsin test (SMD = -0.69) and greater left and right cortical areas (SMD = 0.85; SMD = 0.92); greater surface area in the left anterior cingulate (SMD = 1.32), right medial orbitofrontal cortex (SMD = 1.17), right superior frontal gyrus (SMD = 0.82), and right and left precentral gyrus (SMD = 1.33; SMD = 0.98); greater volume of the right amygdala (SMD = 0.57), right hippocampus (SMD = 0.66), right putamen (SMD = 0.87) and right thalamus (SMD = .67). In the lithium group, a correlation was found with these errors and the thickness of the left precentral gyrus (ρ = -0.78), the volume of the right thalamus (ρ = -0.44), and the right amygdala (ρ = 0.6).

CONCLUSIONS

The lithium group had better cognitive flexibility and greater dimension in some frontal and subcortical cortical regions. Furthermore, there was a moderate to high correlation between performance in this executive function and the thickness of the right precentral gyrus, and the volumes of the thalamus and the right amygdala. These findings could suggest a neuroprotective effect of lithium.

Visual Event-Related Potentials under External Emotional Stimuli in Bipolar I Disorder with and without Hypersexuality

Hypersexuality is related to functions of personality and emotion and is a salient symptom of bipolar I disorder especially during manic episode. However, it is uncertain whether bipolar I disorder with (BW) and without (BO) hypersexuality exhibits different cerebral activations under external emotion stimuli. In 54 healthy volunteers, 27 BW and 26 BO patients, we administered the visual oddball event-related potentials (ERPs) under external emotions of Disgust, Erotica, Fear, Happiness, Neutral, and Sadness. Participants’ concurrent states of mania, hypomania, and depression were also evaluated. The N1 latencies under Erotica and Happiness were prolonged, and the P3b amplitudes under Fear and Sadness were decreased in BW; the P3b amplitudes under Fear were increased in BO. The parietal, frontal, and occipital activations were found in BW, and the frontal and temporal activations in BO under different external emotional stimuli, respectively. Some ERP components were correlated with the concurrent affective states in three groups of participants. The primary perception under Erotica and Happiness, and voluntary attention under Fear and Sadness, were impaired in BW, while the voluntary attention under Fear was impaired in BO. Our study indicates different patterns of visual attentional deficits under different external emotions in BW and BO.

A meta-analysis comparing cognitive function across the mood/psychosis diagnostic spectrum

BACKGROUND

The nature and degree of cognitive impairments in schizoaffective disorder is not well established. The aim of this meta-analysis was to characterise cognitive functioning in schizoaffective disorder and compare it with cognition in schizophrenia and bipolar disorder. Schizoaffective disorder was considered both as a single category and as its two diagnostic subtypes, bipolar and depressive disorder.

METHODS

Following a thorough literature search (468 records identified), we included 31 studies with a total of 1685 participants with schizoaffective disorder, 3357 with schizophrenia and 1095 with bipolar disorder. Meta-analyses were conducted for seven cognitive variables comparing performance between participants with schizoaffective disorder and schizophrenia, and between schizoaffective disorder and bipolar disorder.

RESULTS

Participants with schizoaffective disorder performed worse than those with bipolar disorder (g = -0.30) and better than those with schizophrenia (g = 0.17). Meta-analyses of the subtypes of schizoaffective disorder showed cognitive impairments in participants with the depressive subtype are closer in severity to those seen in participants with schizophrenia (g = 0.08), whereas those with the bipolar subtype were more impaired than those with bipolar disorder (g = -0.23) and less impaired than those with schizophrenia (g = 0.29). Participants with the depressive subtype had worse performance than those with the bipolar subtype but this was not significant (g = 0.25, p = 0.05).

CONCLUSION

Cognitive impairments increase in severity from bipolar disorder to schizoaffective disorder to schizophrenia. Differences between the subtypes of schizoaffective disorder suggest combining the subtypes of schizoaffective disorder may obscure a study's results and hamper efforts to understand the relationship between this disorder and schizophrenia or bipolar disorder.

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

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

Neurocognition Function of Patients With Bipolar Depression, Unipolar Depression, and Depression With Bipolarity

Much evidence shows that some Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5)-defined unipolar depression (UD) with bipolarity manifests bipolar diathesis. Little is known about the cognitive profiles of patients with depression with bipolarity (DWB). The study aimed to investigate the differences in cognitive profiles among patients with bipolar depression (BD), major depressive disorder (namely, UD), and DWB. Drug-naïve patients with BD, UD, and DWB and healthy controls (HC) were recruited (30 cases in each group). Cognitive function was evaluated by THINC-it (THINC-intelligent tool), Wisconsin Card Sorting Test (WCST), and continuous performance test (CPT). For THINC-it, no significant differences of the Z-scores in both objective and subjective factors were found between the DWB group and BD group, but the Z-scores in the BD group were significantly lower than those in the UD group. For WCST, significant differences were found between the BD group and DWB group in the number of responses, categories completed, trails to completed first category, perseverative responses, and perseverative errors. All the indices of WCST in the DWB group were significantly worse than those in the UD group except for trails to completed first category and total number of response correct. For CPT, only scores of leakage responses and false responses in the four-digit number in the BD group and DWB group were significantly higher than those in the UD group; no significant difference was found between the BD group and DWB group. The results indicated that patients with DWB might perform differently from those with UD but similarly to those with BD with cognition impairment.

An exploration of theory of mind performance among men convicted of rape

Several of the known risk factors for sexual violence concern a lack of capacity for engaging in mutually satisfying interpersonal relationships. Socio-cognitive deficits may be approached from a theory of mind (ToM) perspective, where lack of ability to attribute mental states to others is seen as the core feature. This study focuses on imprisoned men (n = 26) convicted of rape against an adult. A video-based measure of ToM (MASC) was applied, depicting social interaction in a dynamic real-life setting. The results showed that the rape-convicted men have a markedly inferior ability to infer the mental states of others. Clinical as well as theoretical implications of the findings are discussed.

Pediatric bipolar disorder: Executive, linguistic, mnemonic, and cognitive efficiency mapping

Neuropsychological assessment can enrich our understanding of Pediatric Bipolar Disorder (PB). This study aimed to: (1) analyze the occurrence of neuropsychological frequency of deficits and difficulties in children with PB; (2) verify whether there is a performance difference between PB type I (PB-I) and PB type II (PB-II)/unspecified, and between PB with and without ADHD; and (3) verify the cognitive efficiency differences within the PB group and control groups, and among clinical subgroups. Participants in the study were 16 children diagnosed with PB and 40 children with typical development (6-12 years old). The results indicated a high frequency of deficits/difficulties in verbal fluency, cognitive efficiency in performing basic abilities, inhibitory control, cognitive flexibility, and working memory, with emphasis on verbal and executive losses. There were indications that type PB-I and comorbidity with ADHD negatively impact a child's neuropsychological development. The clinical group showed more cognitive efficiency losses compared with the control group, and greater losses were observed in PB-I and in PB with ADHD. The role of neuropsychological evaluation in multidomain and nonlinear statistical analysis is critical to gaining an understanding of the clinical and cognitive heterogeneity of PB.

Correlation Between Cognitive Performance and Structural Neuroanatomy in Patients with Type I Bipolar Affective Disorder Treated with and Without Lithium

INTRODUCTION

Lithium treatment of bipolar disorder (BD) has been associated with less cognitive impairment and fewer changes in structural brain anatomy compared to other treatments. However, the studies are heterogeneous and few assess whether these effects are related. The objective of this study was to evaluate and relate cognitive performance and structural neuroanatomy in patients treated with and without lithium.

METHODS

Cross-sectional study that included 48 subjects with BD-I, of which 22 were treated with lithium and 26 without lithium. Performance was assessed on Wechsler III (WAIS III), TMT A and B (Trial Making Test) neuropsychological tests, California verbal learning test (CVLT), Rey complex figure test and Wisconsin card sorting test. Brain structures obtained by magnetic resonance imaging (MRI) were evaluated. The standardised mean difference (SMD) between both groups was calculated, adjusted for confounding variables using a propensity score, and the Spearman correlation coefficient (ρ) was used to assess the relationship between cognitive performance and neuroanatomical regions.

RESULTS

Compared to the group without lithium, the group with lithium had fewer perseverative errors in the Wisconsin test (SMD = -0.69) and greater left and right cortical areas (SMD = 0.85; SMD = 0.92); greater surface area in the left anterior cingulate (SMD = 1.32), right medial orbitofrontal cortex (SMD = 1.17), right superior frontal gyrus (SMD = 0.82), and right and left precentral gyrus (SMD = 1.33; SMD = 0.98); greater volume of the right amygdala (SMD = 0.57), right hippocampus (SMD = 0.66), right putamen (SMD = 0.87) and right thalamus (SMD=.67). In the lithium group, a correlation was found with these errors and the thickness of the left precentral gyrus (ρ = -0.78), the volume of the right thalamus (ρ =-0.44), and the right amygdala (ρ = 0.6).

CONCLUSIONS

The lithium group had better cognitive flexibility and greater dimension in some frontal and subcortical cortical regions. Furthermore, there was a moderate to high correlation between performance in this executive function and the thickness of the right precentral gyrus, and the volumes of the thalamus and the right amygdala. These findings could suggest a neuroprotective effect of lithium.

Effects of mood episodes and comorbid anxiety on neuropsychological impairment in patients with bipolar spectrum disorder

OBJECTIVES

Cases of patients with bipolar disorder (BD) having neuropsychological impairment have been reported, although inconsistently. The possibility of comorbidity with anxiety disorder (AD) has been suggested. The association between mood episodes and AD comorbidity on neuropsychological performance is unclear and thus was investigated in the current study.

METHODS

All participants were informed about and agreed to participate in this study. Patients with BD were recruited from outpatient and inpatient settings, and healthy controls (HCs) were recruited as a comparison group. Six hundred and twenty-eight participants (175 HCs and 453 BD-56 BDI and 397 BDII) were studied based on their current mood episode, namely, depressive (BD_d ), manic/hypomanic (BDm), mixed (BDmix), and euthymic (BDeu), compared with/without AD comorbidity (164 with AD).

RESULTS

Compared to HCs, all BD groups had significantly more impaired neuropsychological profiles, but the BDeu group was found to have less impairment in memory and executive function than the episodic BD groups. The percentage of AD comorbidity in BDd, BDm, BDmix, and BDeu was 33.9%, 40.3%, 33.0%, and 35.6%, respectively (χ²  = 1.61, p > .05). The results show that AD plays a different role in neuropsychological impairment across various mood episodes in BD.

CONCLUSION

Memory impairment and executive dysfunction may be state-like cognitive phenotypes and are affected by AD comorbidity during mixed and depressive episodes in BD, while sustained attention deficiencies are more like trait markers, regardless of mood episodes, and persist beyond the course of the illness. The AD comorbidity effect on attentional deficit is greater when suffering from a manic episode.

The social cognitive ability in Han Chinese euthymic patients with bipolar I and bipolar II disorder

BACKGROUND/PURPOSE

Although social cognitive deficits were found in euthymic patients of bipolar disorder (BD), the characteristics of social cognition in Han Chinese euthymic BD patients remain obscure. This study aimed to examine social cognition in Han Chinese euthymic BD patients relative to healthy controls (HC). Moreover, we explore the differences in social cognition between euthymic BD I and BD II patients.

METHODS

43 Han Chinese BD patients (BD-I:25, BD-II:18) and 28 HC were recruited. All patients were euthymic (Young Mania Rating Scale (YMRS) ≤ 7 and Hamilton Depression Rating Scale (HDRS) ≤ 7). Social cognitive ability was measured using Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT), including 4 branches: perceiving emotions, facilitating emotions, understanding emotions, and managing emotions. Continuous performance Test (CPT) and Wisconsin Card Sorting Test (WCST) were used to examine attention and executive function.

RESULTS

Significant difference in understanding emotions branch of MSCEIT was found between BD patients and HCs (Mann-Whitney U test, p = 0.005). Besides, BD patients had significantly worse performance in WCST and CPT. However, the differences in WCST, CPT, MSCEIT total scores and its subscales were not significant between BD I and BD II patients.

CONCLUSION

Euthymic Han Chinese BD patients exhibit significant social cognitive deficits in understanding emotion and cognitive dysfunction in attention and executive function. Furthermore, Han Chinese BD I patients showed similar social cognitive and general cognitive ability as compared with BD II patients. Social cognitive rehabilitation on both euthymic BD I and II patients should be considered.

The GLP-1 receptor agonist liraglutide reverses mania-like alterations and memory deficits induced by D-amphetamine and augments lithium effects in mice: Relevance for bipolar disorder

Metabolic and psychiatric disorders present a bidirectional relationship. GLP-1 system, known for its insulinotropic effects, has also been associated with numerous regulatory effects in cognitive and emotional processing. GLP-1 receptors (GLP-1R) agonists present neuroprotective and antidepressant/anxiolytic properties. However, the effects of GLP-1R agonism in bipolar disorder (BD) mania and the related cognitive disturbances remains unknown. Here, we investigated the effects of the GLP-1R agonist liraglutide (LIRA) at monotherapy or combined with lithium (Li) against D-amphetamine (AMPH)-induced mania-like symptoms, brain oxidative and BDNF alterations in mice. Swiss mice received AMPH 2 mg/kg or saline for 14 days. Between days 8-14, they received LIRA 120 or 240 μg/kg, Li 47.5 mg/kg or the combination Li + LIRA, on both doses. After behavioral evaluation the brain areas prefrontal cortex (PFC), hippocampus and amygdala were collected. AMPH induced hyperlocomotion, risk-taking behavior and multiple cognitive deficits which resemble mania. LIRA reversed AMPH-induced hyperlocomotion, working and recognition memory impairments, while Li + LIRA240 rescued all behavioral changes induced by AMPH. LIRA reversed AMPH-induced hippocampal oxidative and neurotrophic changes. Li + LIRA240 augmented Li antioxidant effects and greatly reversed AMPH-induced BDNF changes in PFC and hippocampus. LIRA rescued the weight gain induced by Li in the course of mania model. Therefore, LIRA can reverse some mania-like behavioral alterations and combined with Li augmented the mood stabilizing and neuroprotective properties of Li. This study points to LIRA as a promising adjunctive tool for BD treatment and provides the first rationale for the design of clinical trials investigating its possible antimanic effect.

Impact of metabolic syndrome and clinical features on functioning in patients with bipolar disorder: a cross-sectional study

Objective:

The metabolic syndrome (MS) is highly prevalent among patients with bipolar disorder (BD), and may affect progression, functioning, and comorbid conditions in BD. The aim of this study was to investigate the effect of clinical variables and MS on overall functioning and specific areas of functioning in patients with BD.

Methods:

A total of 210 participants (140 participants with BD I and BD II in remission and 70 non-psychiatric control subjects) were included. The investigators administered the Young Mania Rating Scale (YMRS), the Bipolar Depression Rating Scale (BDRS), the Global Assessment of Functioning Scale (GAF), and the Bipolar Disorder Functioning Scale (BDFS). The participants completed the Beck Depression Scale (BDS) and the Beck Anxiety Scale (BAS). MS was diagnosed according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Hierarchical regression analysis was used to investigate potential correlations of comorbid MS with clinical variables and level of functioning.

Results:

Level of functioning did not differ between patients with and without MS. However, there were significant correlations between the level of functioning subscales and the number of depressive episodes (p = 0.033), level of general functioning (p = 0.012), duration of illness (p = 0.012), BDS (p = 0.005), BDRS (p = 0.021), BAS total scores (p = 0.021), number of hypomanic episodes (p = 0.022), number of hospitalizations (p = 0.003), employment status (p = 0.032), and diagnosis of BD I (p = 0.007) and BD II (p = 0.044).

Conclusion:

Our findings suggest that clinical variables had a greater effect on functioning than MS in BD patients.

Elated or sad mood induction affects the attention of patients with a bipolar disorder less than that of patients with a depressive disorder

Introduction: The role of acute mood states as mediating factors in cognitive impairment in patients with mania or depression is not sufficiently clear. Similarly, the extent to which cognitive impairment is trait or state-specific remains an open question. Therefore, the aim of this study was to investigate the effect of a mood-induction on attention in patients with an affective disorder.Methods: Twenty-two depressed bipolar patients, 10 manic bipolar patients, 17 with a depressive episode (MDE), and 24 healthy controls performed the Attention-Network-Test (ANT). In a within-participants design, elated and sad moods were induced by an autobiographic recall and measured on a self-report scale. Subsequently, participants performed the ANT again.Results: The modulating effect of the elated mood induction on attention was small. Only the MDE group displayed moderate improvements in selective attention and tonic alertness. Surprisingly, after the sad mood induction, patients with MDE improved moderately on phasic and tonic alertness. Phasic alertness was also enhanced in patients with mania. Finally, after the mood induction, patients with MDE showed the largest variability in attentional performance.Conclusions: Results showed only small effects of mood induction on attention. This supports the view that attention deficits reflect trait variables.

Autobiographical memory deficits in remitted patients with bipolar disorder I: The effect of impaired memory retrieval

Autobiographical memory (AM) has been studied extensively in different psychiatric disorders. However, less is known about AM in bipolar disorder (BD). Aim of the present study was to investigate BD patients' ability to recall episodic and semantic autobiographical memories after controlling for the effect of other possible neurocognitive deficits. Participants included 30 clinically remitted outpatients with BD type I and 30 healthy controls, matched for age, gender and educational level. Autobiographical memory was examined by the Questionnaire of Autobiographical Memory. Premorbid intellectual functioning, verbal memory, verbal fluency, attention and working memory were also assessed. Bipolar patients were impaired in both episodic and semantic AM, compared with healthy individuals. Deficits involved recall of memories from childhood-adolescence, early adulthood and recent life. Additionally, patients were impaired in verbal memory compared with controls. Differences between study groups in both episodic and semantic AM remained significant even after controlling for the effect of verbal memory deficits. Remitted BD-I patients showed deficits in recalling personal episodic memories and facts dating to three different life periods. These deficits were independent of patients' lower verbal memory performance. Additional research is required to gain a better understanding of the pattern and the mechanisms underlying AM impairment in BD.

Cognitive variability in bipolar I disorder: A cluster-analytic approach informed by resting-state data

BACKGROUND

While the presence of cognitive performance deficits in bipolar disorder I (BD-I) is well established, there is no consensus about which cognitive abilities are affected. Heterogeneous phenotypes displayed in BD-I further suggest the existence of subgroups among the disorder. The present study sought to identify different cognitive profiles among BD-I patients as well as potentially underlying neuronal network changes.

METHODS

54 euthymic BD-I patients underwent cognitive testing and resting state neuroimaging. Hierarchical cluster-analysis was performed on executive function scores of bipolar patients. The derived clusters were compared against 54 age-, gender- and IQ-matched healthy controls (HC) to facilitate the interpretation of results. Further, resting state network properties were compared to identify differences probably underlying cognitive profiles.

RESULTS

A three-cluster solution emerged. Cluster 1 (n = 22) was characterized by deficits in cognitive flexibility and motor inhibition, cluster 2 (n = 12) displayed impulsive decision-making, while cluster 3 (n = 20) showed good visuospatial planning. Weaker connections in cluster 1 compared to cluster 2 were found between regions activated during tasks cluster 1 showed deficits on. Cluster 3 had a higher modularity than cluster 2, which correlated positively with problem solving performance and risk-taking in this cluster.

CONCLUSION

Obtained clusters showed distinct cognitive profiles, characterized by deficits and strengths, most of which remained precluded in a general comparison. Weaker interregional connections and separated subnetworks might underly behavioral deficits and strengths, respectively. The findings help explain the phenotypic heterogeneity observed in BD-I. This article is part of the Special Issue entitled 'Current status of the neurobiology of aggression and impulsivity'.

Genome-wide analysis reveals extensive genetic overlap between schizophrenia, bipolar disorder, and intelligence

Schizophrenia (SCZ) and bipolar disorder (BD) are severe mental disorders associated with cognitive impairment, which is considered a major determinant of functional outcome. Despite this, the etiology of the cognitive impairment is poorly understood, and no satisfactory cognitive treatments exist. Increasing evidence indicates that genetic risk for SCZ may contribute to cognitive impairment, whereas the genetic relationship between BD and cognitive function remains unclear. Here, we combined large genome-wide association study data on SCZ (n = 82,315), BD (n = 51,710), and general intelligence (n = 269,867) to investigate overlap in common genetic variants using conditional false discovery rate (condFDR) analysis. We observed substantial genetic enrichment in both SCZ and BD conditional on associations with intelligence indicating polygenic overlap. Using condFDR analysis, we leveraged this enrichment to increase statistical power and identified 75 distinct genomic loci associated with both SCZ and intelligence, and 12 loci associated with both BD and intelligence at conjunctional FDR < 0.01. Among these loci, 20 are novel for SCZ, and four are novel for BD. Most SCZ risk alleles (61 of 75, 81%) were associated with poorer cognitive performance, whereas most BD risk alleles (9 of 12, 75%) were associated with better cognitive performance. A gene set analysis of the loci shared between SCZ and intelligence implicated biological processes related to neurodevelopment, synaptic integrity, and neurotransmission; the same analysis for BD was underpowered. Altogether, the study demonstrates that both SCZ and BD share genetic influences with intelligence, albeit in a different manner, providing new insights into their genetic architectures.

Memory Impairment and Plasma BDNF Correlates of the BDNF Val66Met Polymorphism in Patients With Bipolar II Disorder

Studies suggest that a functional polymorphism of brain-derived neurotrophic factor (BDNF), polymorphism BDNF Val⁶⁶Met affects cognitive functions, however, the effect is unclear in bipolar II (BD-II) disorder. We used the Wechsler Memory Scale-third edition (WMS-III), the presence of the BDNF Val⁶⁶Met polymorphism, and plasma concentrations of BDNF to investigate the association between memory impairment and BDNF in BD-II disorder. We assessed the memory functions of 228 BD-II patients and 135 healthy controls (HCs). BD-II patients had significantly lower scores on five of the eight WMS-III subscales. In addition to education, the BDNF polymorphism were associated with the following subscales of WMS-III, auditory delayed memory, auditory delayed recognition memory and general memory scores in BD-II patients, but not in HC. Moreover, BD-II patients with the Val-homozygote scored significantly higher on the visual immediate memory subscale than did those with the Met/Met and Val/Met polymorphisms. The significantly positive effect of the Val-homozygote did not have a significantly positive effect on memory in the HC group, however. We found no significant association between BDNF polymorphisms and plasma concentrations of BDNF. The plasma BDNF was more likely to be associated with clinical characteristics than it was with memory indices in the BD-II group. The impaired memory function in BD-II patients might be dependent upon the association between the BDNF Val⁶⁶Met polymorphism and peripheral BDNF levels.

ALDH2 modulated changes in cytokine levels and cognitive function in bipolar disorder: A 12-week follow-up study

OBJECTIVES

We investigated the association of the aldehyde dehydrogenase 2 ( ALDH2) polymorphism (rs671), which is involved with the dopaminergic function, and with changes in cytokine levels and cognitive function, in a 12-week follow-up study in patients with bipolar disorder.

METHODS

Patients with a first diagnosis of bipolar disorder were recruited. Symptom severity and levels of plasma cytokines (tumor necrosis factor α, C-reactive protein, interleukin 6 and transforming growth factor β1) were examined during weeks 0, 1, 2, 4, 8 and 12. Neurocognitive function was evaluated at baseline and endpoint. The ALDH2 polymorphism genotype was determined.

RESULTS

A total of 541 patients with bipolar disorder were recruited, and 355 (65.6%) completed the 12-week follow-up. A multiple linear regression analysis showed a significant ( p = 0.000226) association between the ALDH2 polymorphism and changes in C-reactive protein levels. Different aspects of cognitive function improved in patients with different ALDH2 genotypes. Only patients with the ALDH2*1*1 genotype showed significant correlations between improvement of cognitive function and increased transforming growth factor -β1.

CONCLUSION

The ALDH2 gene might influence changes in cytokine levels and cognitive performance in patients with bipolar disorder. Additionally, changes in cytokine levels and cognitive function were correlated only in patients with specific ALDH2 genotypes.

Neurocognitive features in clinical subgroups of bipolar disorder: A meta-analysis

OBJECTIVE

There is a significant cognitive heterogeneity in bipolar disorder (BD). The aim of this systematic review was to examine the potential distinctive neuropsychological of features of clinical subgroups of BD. A literature search investigating cognitive differences between potential subtypes of BD was conducted.

METHODS

It was possible to conduct a meta-analysis of studies investigating the relationship between cognitive deficits and subgroups of DSM-IV BD (type I (BD-I) and type II (BD-II)), subgroups based on history of psychosis (PBD and NPBD). The cognitive domains investigated in this meta-analysis included verbal memory, visual memory, processing speed, executive functions speed (EF-speed), EF-accuracy, attention, working memory, social cognition. Current meta-analysis included 48 reports and compared cognitive performances of 1211 BD-I and 836 BD-II patients. It also compared cognitive functioning in 1017 PBD and 744 NPBD patients.

RESULTS

Both history of psychosis (d = 0.19) and BD-I (d = 0.17) diagnosis were associated with modestly more pronounced global cognitive impairment. In specific domains, BD-I significantly underperformed BD-II in verbal memory, processing speed, EF-speed, EF-accuracy (d = 0.15-0.26). PBD was associated with significantly impaired cognition compared to NPBD in verbal memory, processing speed, EF-speed, EF-accuracy, working memory and social cognition (d = 0.12-0.28).

CONCLUSION

In BD, history of psychosis and full-manic episode are modestly associated with increased cognitive deficits. Neurocognitive differences between clinical subtypes of BD are quite subtle and are not distinctive. Furthermore, other factors reflecting differences in illness severity can explain observed between-group differences. Most of the cognitive heterogeneity in BD cannot be explained by proposed subtypes of BD.

The aldehyde dehydrogenase 2 polymorphisms on neuropsychological performance in bipolar II disorder with or without comorbid anxiety disorder

Anxiety disorders (ADs), the most common comorbid illnesses with bipolar disorder (BP) has been reported to associate with dopamine system. Dopamine, metabolized to 3,4-dihydroxyphenylacetic acid (DOPAC) by aldehyde dehydrogenase 2 (ALDH2), and the distribution of the ALDH2*1/*1, and ALDH2*1/*2+ALDH*2/*2 alleles in the Han Chinese general population is relatively equal. The association between dopamine metabolic enzymes and cognitive performance in patients with bipolar II disorder (BP-II) comorbid with AD is unclear. This study proposed to explore the role of ALDH2 polymorphisms on neuropsychological performance between BP-II comorbid with or without AD. One hundred ninety-seven BP-II patients with and without a comorbid AD were recruited and compared with 130 healthy controls (HCs). A polymerase chain reaction and a restriction fragment length polymorphism analysis were used to determine genotypes for ALDH2, and study participants underwent neuropsychological tests. An interaction between AD comorbidity and the ALDH2 polymorphisms was found in different domain of cognitive dysfunction in the BP-II patients. The ALDH2 polymorphisms might have different effects on the neuropsychological performance of BP-II patients with and without comorbid AD.

Diffusion imaging study of the Corpus Callosum in bipolar disorder

Structural and diffusion imaging studies have provided some evidence of abnormal organization of Corpus Callosum (CC) in Bipolar Disorder (BD). Therefore, by using Diffusion Weighted Imaging (DWI), which allows to build subtle prediction models of fiber integrity for white matter (WM) tracts, this study aims to further explore the microstructure integrity of CC in BD patients compared to matched healthy controls. Twenty-four chronic patients with BD and 35 healthy controls were included in the study. Circular regions of interest were placed, on diffusion images, in the left and right side of callosal regions (i.e. rostrum/genu, anterior body, posterior body, splenium) and the Apparent Diffusion Coefficient (ADC) was then calculated. Significantly increased ADC values were found in right anterior body and in right splenium in BD patients compared to healthy controls (all p < 0.05, Bonferroni corrected). In this study, we found abnormally increased ADC callosal values in BD suggesting microstructural anomalies specifically in the right hemisphere. Interestingly, this finding further supports the presence of an altered inter-hemispheric communication between frontal and temporo-parietal association areas in patients with BD, which may ultimately result in clinical symptoms and cognitive deficits.

Investigating gaze processing in euthymic bipolar disorder: Impaired ability to infer mental state and intention, but preservation of social attentional orienting

Euthymic bipolar disorder (BD) has been associated with subtle impairment in face processing. However, it is not known whether their difficulties extend to the processing of gaze. In the present study, two tasks, both of which rely on the ability to make use of the eye region of a pictured face, were used: the Reading the Mind in the Eyes test and the Eye-gaze cueing task. Compared to healthy controls, BD patients were impaired at judging mental state from images of the face but showed normal susceptibility to the direction of gaze as an attentional cue. These findings suggest that BD patients present selective gaze processing impairment, limited to the sensitivity to intention and emotion. This impairment could account at least partially for the higher levels of interpersonal problems generally observed in BD.

Evaluation of the interaction between genetic variants of GAD1 and miRNA in bipolar disorders

BACKGROUND

Glutamic acid dehydrogenase 1 (GAD1) serves as the rate-limiting enzyme for synthesizing GABA, and is reported to be associated with several psychiatric disorders. The present study examined the effects of GAD1 genetic variants on bipolar disorder (BD) and its subtypes. Moreover, we investigated functional interactions between genetic variants and miRNAs via algorithm prediction and experimental validation.

METHODS

A case-control study was conducted with 280 BD patients and 200 healthy controls. Eight tag SNPs in GAD1 were genotyped. For associated markers, we performed in silico prediction for their potential functions through SNP-miRNA interactions by establishing a scoring system to combine information from several miRNA predictive algorithms. We then tested allelic expression differences using Dual-Glo luciferase reporter assays for the selected SNP-miRNA pair. Lastly, we examined the associations of the GAD1 gene and BD in two additional independent datasets with a few thousand samples for replication.

RESULTS

Marker rs3749034 was associated with BD, in particular the BD-II subtype. According to our scoring system, several candidate miRNAs were predicted to interact with rs3749034, and hsa-miR-504 had the highest score. Findings from an in vitro experiment revealed a non-statistically significant trend for lower gene expression level with the A allele of rs3749034 compared with the G allele. The association between rs3749034 and BD was not replicated in either of the independent datasets. Instead, other rarer genetic variants in GAD1 showed suggestive signals (e.g. rs575441409, p-value = 3.8*10^-4, D' = 1 with rs3749034) with BD in the Taiwanese dataset.

LIMITATIONS

The present study considered common genetic variants only. In addition, we only used a 293T cell-line in conducting luciferase reporter assays, as no primary cell-lines from patient samples were available to differentiate the effects between BD subtypes.

CONCLUSIONS

Our results demonstrate a weak effect of the GAD1 gene on the risk of bipolar illness, and the associated marker might represent a proxy for real signals of rare variants.

Neurocognition in patients with psychotic and non-psychotic bipolar I disorder. A comparative study with individuals with schizophrenia

BACKGROUND

It has been suggested that patients with bipolar disorder with psychotic symptoms (BD-P) have larger neurocognitive impairment than patients with bipolar disorder without a history of psychotic symptoms (BD-NP). The objective of this study was to compare neurocognitive performance of BD-P and BD-NP relative to a group of patients with schizophrenia (SZ), and healthy controls (HC).

METHODS

Neurocognitive function was examined in 100 subjects with bipolar I disorder (50 BD-P, 50 BD-NP), 50 SZ, and 51 HC. All patients with BD fulfilled criteria for euthymia, while all SZ patients were stabilised for at least the previous 3 months.

RESULTS

Patients with BD-P and BD-NP performed worse than HC in all neurocognitive measures, except for sustained attention. Differences between BD-P and BD-NP were subtle and circumscribed to the working memory domain (effect size: 0.29). SZ performed worse than BD-NP in the neurocognitive composite index (NCI) and in the working memory domain. There were no differences between SZ and BD-P in any neurocognitive measure.

LIMITATIONS

The relatively small sample size, the cross-sectional design and, that patients were receiving pharmacological treatment are the main limitations of this study.

CONCLUSIONS

Our findings show that the three groups of patients have a large neurocognitive impairment. Differences are quantitative and only present in some neurocognitive domains, such as working memory. These results suggest that patients with BD and SZ can benefit from the same strategies of cognitive remediation.

Classification of cognitive performance in bipolar disorder

OBJECTIVE

To understand the etiology of cognitive impairment associated with bipolar disorder, we need to clarify potential heterogeneity in cognitive functioning. To this end, we used multivariate techniques to study if the correlation structure of cognitive abilities differs between persons with bipolar disorder and controls.

METHOD

Clinically stable patients with bipolar disorder (type I: n = 64; type II: n = 44) and healthy controls (n = 86) were assessed with a wide range of cognitive tests measuring executive function, speed, memory, and verbal skills. Data were analysed with multivariate techniques.

RESULTS

A distinct subgroup (∼30%) could be identified that performed significantly poorer on tests concerning memory function. This cognitive phenotype subgroup did not differ from the majority of bipolar disorder patients with respect to other demographic or clinical characteristics.

CONCLUSIONS

Whereas the majority of patients performed similar to controls, a subgroup of patients with bipolar disorder differed substantially from healthy controls in the correlation pattern of low-level cognitive abilities. This suggests that cognitive impairment is not a general trait in bipolar disorder but characteristic of a cognitive subgroup. This has important clinical implications for cognitive rehabilitation and remediation.

Disentangling Working Memory Functioning in Mood States of Bipolar Disorder: A Systematic Review

Working memory (WM) deficits are often reported in patients with Bipolar Disorder (BD). However, it is not clear about the nature of these WM deficits (update or serial order processes) and their association with each BD states (euthymic, mania, and depressive). This review investigated the association between BD patient's states and the functioning of WM components. For this purpose, we carried out a systematic review fulfilling a search in the databases Medline, Scopus, SciELO, and Web of Science using specific terms in the abstracts of the articles that generated 212 outcomes in the restricted period from 2005 to 2016. Twenty-three papers were selected, completely read, and analyzed using PICOS strategy. The mood episodes predicted deficits in different components of WM in BD patients (the phonological loop or visuospatial sketchpad) and were associated with different WM processes (updating and serial recall). Lower cognitive scores persist even in remission of symptoms. This result suggests that WM deficit apparently is stage-independent in BD patients. Furthermore, findings suggest that the neutral point on Hedonic Detector component of WM could be maladjusted by BD.

Course of neurocognitive function in first treatment bipolar I disorder: One-year follow-up study

Neurocognitive impairment has been found to be a marked feature in bipolar disorder (BD), also in the early phase of the illness. The longitudinal course of neurocognitive functioning, however, remains sparsely investigated. The aims of the study were to investigate the course of neurocognitive function in BD I, and to what degree neurocognitive change or stability is observed also on the individual level. Forty-two patients and 153 comparable healthy controls were assessed at baseline and one-year follow-up. Compared to the healthy control (HC) group BD I patients perform significantly poorer at both baseline and follow-up across all neurocognitive domains and on most neurocognitive subtests. Neurocognitive impairment remained stable for most patients from baseline to follow-up, both on a group level and when investigating individual trajectories, indicative of a relatively stable course of neurocognitive functioning in the early phase of BD I.

Facial emotion labeling in unaffected offspring of adults with bipolar I disorder

BACKGROUND

Young people 'at risk' for developing Bipolar Disorder have been shown to have deficits in facial emotion labeling across emotions with some studies reporting deficits for one or more particular emotions. However, these have included a heterogeneous group of young people (siblings of adolescents and offspring of adults with bipolar disorder), who have themselves diagnosed psychopathology (mood disorders and neurodevelopmental disorders including ADHD).

METHODS

24 offspring of adults with bipolar I disorder and 34 offspring of healthy controls were administered the Diagnostic Analysis of Non Verbal Accuracy 2 (DANVA 2) to investigate the ability of participants to correctly label 4 emotions: happy, sad, fear and anger using both child and adult faces as stimuli at low and high intensity.

RESULTS

Mixed effects modelling revealed that the offspring of adults with bipolar I disorder made more errors in both the overall recognition of facial emotions and the specific recognition of fear compared with the offspring of healthy controls. Further more errors were made by offspring that were male, younger in age and also in recognition of emotions using 'child' stimuli.

LIMITATIONS

The sample size, lack of blinding of the study team and the absence of any stimuli that assess subjects' response to a neutral emotional stimulus are limitations of the study.

CONCLUSIONS

Offspring (with no history of current or past psychopathology or psychotropic medication) of adults with bipolar I disorder displayed facial emotion labeling deficits (particularly fear) suggesting facial emotion labeling may be an endophenotype for bipolar disorder.

Associations between mood instability and emotional processing in a large cohort of bipolar patients

BACKGROUND

Aberrant emotional biases have been reported in bipolar disorder (BD), but results are inconsistent. Despite the clinical relevance of chronic mood variability in BD, there is no previous research investigating how the extent of symptom fluctuations in bipolar disorder might relate to emotional biases. This exploratory study investigated, in a large cohort of bipolar patients, whether instability in weekly mood episode symptoms and other clinical and demographic factors were related to emotional bias as measured in a simple laboratory task.

METHOD

Participants (N = 271, BDI = 206, BDII = 121) completed an 'emotional categorization and memory' task. Weekly self-reported symptoms of depression and mania were collected prospectively. In linear regression analyses, associations between cognitive bias and mood variability were explored together with the influence of demographic and clinical factors, including current medication.

RESULTS

Greater accuracy in the classification of negative words relative to positive words was associated with greater instability in depressive symptoms. Furthermore, greater negative bias in free recall was associated with higher instability in manic symptoms. Participants diagnosed with BDII, compared with BDI, showed overall better word recognition and recall. Current antipsychotic use was associated with reduced instability in manic symptoms but this did not impact on emotional processing performance.

CONCLUSIONS

Emotional processing biases in bipolar disorder are related to instability in mood. These findings prompt further investigation into the underpinnings as well as clinical significance of mood instability.

Cognitive reserve in bipolar disorder: relation to cognition, psychosocial functioning and quality of life

OBJECTIVE

Cognitive reserve (CR) is a concept that was postulated as a protective factor for some clinical symptoms after the observation that there is not a direct relationship between the degree of brain damage and its clinical manifestation. This study aimed to explore the association between CR and the main outcomes in bipolar disorder (BD): cognitive functions, psychosocial functioning and perceived quality of life.

METHOD

A sample of 224 euthymic bipolar patients was assessed with a neuropsychological battery, the Functioning Assessment Short Test and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). CR was calculated through three proxies: estimated premorbid Intelligent Quotient, educational level and occupational attainment. Relationships between CR and cognitive functions, psychosocial functioning and quality of life were assessed by multiple linear regression models.

RESULTS

Higher CR was associated with better cognitive functioning (P < 0.001 in processing speed, working memory, verbal and visual memory, and executive function; P = 0.026 in attention) and better psychosocial functioning (P = 0.008). For quality of life, CR was positively associated with the physical component of the SF-36 (P = 0.016) but negatively associated with the mental component (P = 0.004).

CONCLUSION

The results suggest that CR may play an important role in the course and prognosis of bipolar patients and it should be considered in both clinical and research settings related to BD.

Cognitive variability in bipolar II disorder: who is cognitively impaired and who is preserved

OBJECTIVES

Although it is well established that euthymic patients with bipolar disorder can have cognitive impairment, substantial heterogeneity exists and little is known about the extent and severity of impairment within the bipolar II disorder subtype. Therefore, the main aim of this study was to analyze cognitive variability in a sample of patients with bipolar II disorder.

METHODS

The neuropsychological performance of 116 subjects, including 64 euthymic patients with bipolar II disorder and 52 healthy control subjects, was examined and compared by means of a comprehensive neurocognitive battery. Neurocognitive data were analyzed using a cluster analysis to examine whether there were specific groups based on neurocognitive patterns. Subsequently, subjects from each cluster were compared on demographic, clinical, and functional variables.

RESULTS

A three-cluster solution was identified with an intact neurocognitive group (n = 29, 48.3%), an intermediate or selectively impaired group (n = 24, 40.0%), and a globally impaired group (n = 7, 11.6%). Among the three clusters, statistically significant differences were observed in premorbid intelligence quotient (p = 0.002), global functional outcome (p = 0.021), and leisure activities (p = 0.001), with patients in the globally impaired cluster showing the lowest attainments. No differences in other clinical characteristics were found among the groups.

CONCLUSIONS

These results confirm that neurocognitive variability is also present among patients with bipolar II disorder. Approximately one-half of the patients with bipolar II disorder were cognitively impaired, and among them 12% were severely and globally impaired. The identification of different cognitive profiles may help to develop cognitive remediation programs specifically tailored for each cognitive profile.

A pilot study of a combined group and individual functional remediation program for patients with bipolar I disorder

BACKGROUND

Bipolar disorder has been associated with a decrease in cognitive functioning affecting the functional outcome of patients independent of mood states. However, there have only been few attempts to investigate the effects of functional remediation for patients with bipolar disorder. The current study investigates the feasibility and effectiveness of a combined group and individual functional remediation program for bipolar disorder, including both patients and their caregivers.

METHODS

Twelve participants diagnosed with bipolar I disorder, and their caregivers, were treated with a combined group and individual functional remediation program. The feasibility of the program was evaluated by dropout rates and participants' evaluations of the program. The effectiveness of the program was explored through the assessment of functional outcome at baseline, immediately post-treatment, and follow-up three months later.

RESULTS

The results indicate a high degree of satisfaction and a low dropout rate with the current program. Assessment of outcomes suggests improved functioning in the areas of autonomy and occupational functioning, evolving from baseline to follow-up.

LIMITATIONS

Due to a small sample size and the lack of a control group the results are preliminary.

CONCLUSIONS

This relatively brief intervention offers a more tailor-made approach to functional remediation and shows good feasibility, acceptability and improvement of functioning in patients with bipolar I disorder.

Bipolar Depression and Cognitive Impairment: Shared Mechanisms and New Treatment Avenues

Depression and cognitive impairment are pervasive and highly disabling aspects of bipolar disorder. Although cognitive impairment is partially independent from mood episodes, depressive symptoms may increase the risk of cognitive impairment in bipolar disorder through inflammatory processes as well as health risks such as obesity and sedentary behavior. Novel treatment avenues at the intersection of bipolar depression and cognitive impairment target inflammation directly or indirectly health behaviors such as diet, physical activity, and sleep hygiene.

History of psychosis and previous episodes as potential explanatory factors for neurocognitive impairment in first-treatment bipolar I disorder

OBJECTIVES

Explanatory factors for the observed neurocognitive impairment in early-stage bipolar I disorder (BD-I) have received little attention. The current study investigated neurocognitive functioning in first-treatment (FT) BD-I compared to FT schizophrenia (SCZ), and healthy controls (HCs), and the effect of history of psychosis and previous episodes in the two clinical groups.

METHODS

A total of 202 FT patients with BD-I (n = 101) and SCZ spectrum disorder (n = 101), in addition to HCs (n = 101), were included. A comprehensive neurocognitive test battery was used to assess verbal learning and memory, executive functioning, processing speed, and attention and working memory. Neurocognitive functioning and the effect of history of psychosis and number of previous episodes were analyzed using separate multivariate analyses of variance and correlation analysis.

RESULTS

FT patients with BD-I performed intermediately between FT SCZ spectrum patients and HCs on all measures. Compared to HCs, FT BD-I showed impaired functioning across all neurocognitive domains. No differences in neurocognitive functioning were observed in psychotic versus nonpsychotic FT patients with BD-I. With the exception of an association between number of manic episodes and two measures of executive function in FT BD-I, no associations were found between number of episodes and neurocognitive performance.

CONCLUSIONS

Neurocognitive impairments were present in FT BD-I, and were not explained by history of psychosis or number of previous psychotic or depressive episodes. There were indications that executive function could be associated with number of previous manic episodes.

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

BACKGROUND

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

METHOD

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

RESULTS

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

LIMITATIONS

No control of pharmacological variables, clinical or demographic characteristics.

CONCLUSIONS

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

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

OBJECTIVES

Cognitive abnormalities are an established part of the symptomatology of mood disorders. However, questions still exist regarding the exact profile of these deficits in terms of the domains most affected, their origins, and their relationship to clinical subtypes. This review aims to examine the current state of the evidence and to examine ways in which the field may be advanced.

METHODS

Studies examining cognitive function in bipolar disorder (BD) and unipolar major depression (MDD) were examined. Given the number and variability of such studies, particular attention was paid to meta-analyses and to meta-regression analyses which examined the possible mediators of cognitive impairment.

RESULTS

Meta-analyses are available for MDD and BD in both depression and euthymia. Several analyses examine mediators. Results do not support the presence of domain specific deficits but rather a moderate deficit across a range of domains in BD and in MDD. The data on clinical mediators is inconsistent, even with regard to the effect of mood state.

CONCLUSIONS

A two-tiered approach, with the broad-based application of standardized measures on a large-scale, and the refined application of theoretically driven experimental development would significantly further our understanding of neurocognitive processing in mood disorder.

Executive dysfunction in bipolar disorder and borderline personality disorder

Objective

The boundary between bipolar disorder (BD) and borderline personality disorder is a controversial one. Despite the importance of the topic, few studies have directly compared these patient groups. The aim of the study was to compare the executive functioning profile of BD and BPD patients.

Method

Executive functioning (sustained attention, problem-solving, planning, strategy formation, cognitive flexibility and working memory) was assessed in BD (n= 30) and BPD outpatients (n= 32) using a computerized assessment battery (Cambridge Neuropsychological Test Automated Battery, CANTAB). The groups were compared to one another as well as to healthy controls.

Results

BD patients showed deficits in strategy formation and in planning (indicated by longer execution time in the ToL task) in comparison to BPD patients and healthy controls. BPD patients showed deficits in planning (short deliberation time in the ToL task) in comparison to BD patients and in comparison to healthy controls. In comparison to healthy controls, BPD patients displayed deficits in problem-solving.

Conclusions

Differences in executive dysfunction between BD and BPD patients suggest that this cognitive dimension may be relevant for the clarification of the boundary between the disorders.

Verbal learning impairment in euthymic bipolar disorder: BDI v BDII

OBJECTIVES

Cognitive impairment is known to occur in bipolar disorder (BD), even in euthymic patients, with largest effect sizes often seen in Verbal Learning and Memory Tasks (VLT). However, comparisons between BD Type-I and Type-II have produced inconsistent results partly due to low sample sizes.

METHODS

This study compared the performance of 183 BDI with 96 BDII out-patients on an adapted version of the Rey Verbal Learning Task. Gender, age, years of education, mood scores and age at onset were all used as covariates. Current medication and a variety of illness variables were also investigated for potential effects on VLT performance.

RESULTS

BDI patients were significantly impaired relative to BDII patients on all five VLT outcome measures after controlling for the other variables [Effect Sizes=.13-.17]. The impairments seem to be unrelated to drug treatment and largely unrelated to illness variables, although age of onset affected performance on three outcome measures and number of episodes of mood elevation affected performance on one.

LIMITATIONS

This study used historical healthy controls. Analysis of potential drug effects was limited by insufficient participants not being drug free. Cross-sectional nature of the study limited the analysis of the potential effect of illness variables.

CONCLUSIONS

This study replicates earlier findings of increased verbal learning impairment in BDI patients relative to BDII in a substantially larger sample. Such performance cannot be wholly explained by medication effects or illness variables. Thus, the cognitive impairment is likely to reflect a phenotypic difference between bipolar sub-types.

Emotion regulation deficits in euthymic bipolar I versus bipolar II disorder: a functional and diffusion-tensor imaging study

OBJECTIVES

Emotion regulation deficits are a core feature of bipolar disorder. However, their potential neurobiological underpinnings and existence beyond bipolar I disorder remain unexplored. Our main goal was to investigate whether both individuals with bipolar I and bipolar II disorder show deficits in emotion regulation during an attention control task, and to explore the neurophysiological underpinnings of this potential deficit.

METHODS

Twenty healthy controls, 16 euthymic participants with bipolar I disorder, and 19 euthymic participants with bipolar II disorder completed psychometric and clinical assessments, a neuroimaging emotion regulation paradigm, and an anatomical diffusion-weighted scan. Groups were matched for age, gender, and verbal IQ.

RESULTS

During the presence of emotional distracters, subjects with bipolar I disorder showed slowed reaction times to targets, and increased blood oxygenation level-dependent (BOLD) responses in the amygdala, accumbens, and dorsolateral prefrontal cortex, but not increased inverse functional connectivity between these prefrontal and subcortical areas, and altered white matter microstructure organization in the right uncinate fasciculus. Subjects with bipolar II disorder showed no altered reaction times, increased BOLD responses in the same brain areas, increased inverse functional connectivity between the prefrontal cortex and amygdala, and no abnormalities in white matter organization.

CONCLUSIONS

Participants with bipolar I disorder showed abnormalities in functional and anatomical connectivity between prefrontal cortices and subcortical structures in emotion regulation circuitry. However, these deficits did not extend to subjects with bipolar II disorder, suggesting fundamental differences in the pathophysiology of bipolar disorder subtypes.

[Validation of the Cognitive Impairment in Psychiatry (SCIP-S) Screen Scale in Patients with Bipolar Disorder I]

BACKGROUND

The Spanish version of the cognitive impairment in psychiatry scale screening scale has been developed as a response to the needs arising in clinical practice during the evaluation of mental illness patients, but the performance is not known in the Colombian population with bipolar disorder I. This paper tries to establish construct validity and stability of the scale in patients with bipolar disorder I in the city of Manizales.

METHODS

Construct validity was estimated by comparing the measurement in two divergent groups, a control group and a group with bipolar disorder I. It was also compared to a Neuropsychological battery measuring the same scale domains. The correlation between each one of the sub-tests of the scale and stability was evaluated through the reliability test-retest in the group with bipolar disorder I.

RESULTS

The scale showed discriminatory capacity in cognitive functioning between the control group and the group with bipolar disorder I. The correlation with the neuropsychological battery was estimated by the Spearman test showing results between 0.36 and 0.77, and the correlation between each sub-test of the scale showed correlations between 0.39 and 0.72. Test-retest was measured with the intraclass correlation coefficient (ICC) and their values were between 0.77 and 0.91.

CONCLUSIONS

The Spanish version of screening scale in the cognitive disorder in psychiatry shows acceptable validity and reliability as a measurement tool in clinical psychiatric practice.

Cognitive functioning in clinically stable patients with bipolar disorder I and II

OBJECTIVES

Bipolar disorder is accompanied by cognitive impairments, which persists during euthymic phases. The purpose of the present study was to identify those neuropsychological tests that most reliably tell euthymic bipolar patients and controls apart, and to clarify the extent to which these cognitive impairments are clinically significant as judged from neuropsychological norms.

METHODS

Patients with bipolar disorder (type I: n = 64; type II: n = 44) and controls (n = 86) were examined with a comprehensive neuropsychological test battery yielding 47 measures of executive functioning, speed, memory, and verbal skills. Multivariate analysis was used to build a model of cognitive performance with the ability to expose underlying trends in data and to reveal cognitive differences between patients and controls.

RESULTS

Patients with bipolar disorder and controls were partially separated by one predictive component of cognitive performance. Additionally, the relative relevance of each cognitive measure for such separation was decided. Cognitive tests measuring set shifting, inhibition, fluency, and searching (e.g., Trail Making Test, Color-Word) had strongest discriminating ability and most reliably detected cognitive impairments in the patient group.

CONCLUSIONS

Both bipolar disorder type I and type II were associated with cognitive impairment that for a sizeable minority is significant in a clinical neuropsychological sense. We demonstrate a combination of neuropsychological tests that reliably detect cognitive impairment in bipolar disorder.

The neurocognitive functioning in bipolar disorder: a systematic review of data

BACKGROUND

During the last decades, there have been many different opinions concerning the neurocognitive function in Bipolar disorder (BD). The aim of the current study was to perform a systematic review of the literature and to synthesize the data in a comprehensive picture of the neurocognitive dysfunction in BD.

METHODS

Papers were located with searches in PubMed/MEDLINE, through June 1st 2015. The review followed a modified version of the recommendations of the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses statement.

RESULTS

The initial search returned 110,403 papers. After the deletion of duplicates, 11,771 papers remained for further evaluation. Eventually, 250 were included in the analysis.

CONCLUSION

The current review supports the presence of a neurocognitive deficit in BD, in almost all neurocognitive domains. This deficit is qualitative similar to that observed in schizophrenia but it is less severe. There are no differences between BD subtypes. Its origin is unclear. It seems it is an enduring component and represents a core primary characteristic of the illness, rather than being secondary to the mood state or medication. This core deficit is confounded (either increased or attenuated) by the disease phase, specific personal characteristics of the patients (age, gender, education, etc.), current symptomatology and its treatment (especially psychotic features) and long-term course and long-term exposure to medication, psychiatric and somatic comorbidity and alcohol and/or substance abuse.

Cognition, functional capacity, and self-reported disability in women with posttraumatic stress disorder: examining the convergence of performance-based measures and self-reports

Individuals with posttraumatic stress disorder (PTSD) experience cognitive impairments and disability in everyday activities. In other neuropsychiatric disorders, impairments in cognition and functional capacity (i.e., the ability to perform everyday tasks) are associated with impairments in real-world functioning, independent of symptom severity. To date, no studies of functional capacity have been conducted in PTSD. Seventy-three women with moderate to severe PTSD underwent assessment with measures of cognition (MATRICS Consensus Cognitive Battery: MCCB), functional capacity (UCSD Performance-Based Skills Assessment-Brief: UPSA-B), PTSD (Clinician-Administered PTSD Scale and PTSD Symptom Scale-Self-report (PSS-SR)), and depression (Montgomery Asberg Depression Rating Scale). Patients also reported their subjective level of disability (Sheehan Disability Scale). Over-reporting of symptom severity was assessed using six validity items embedded within the PSS-SR. Results indicated that on average PTSD patients manifested mild impairments on the functional capacity measure, performing about 1/3 standard deviation below healthy norms, and similar performance on the MCCB. Both clinician-rated and self-rated PTSD symptom severity correlated with self-reported disability but not with functional capacity. Self-reported disability did not correlate with functional capacity or cognition. Greater self-reported disability, depression, and PTSD symptoms all correlated with higher scores on the PSS-SR validity scale. The divergence between objective and subjective measures of disability suggests that individuals' distress, as indexed by symptom validity measures, may be impacting self-reports of disability. Future studies of disability should incorporate objective measures in order to obtain a broad perspective on functioning.