Pharmacological approaches in bipolar disorders and the impact on cognition: a critical overview

Psychiatric symptoms, associated pharmacological treatments and cognitive function: A population-based study of men

BACKGROUND

Psychiatric symptomatology and medications used in their treatment may be modifiable risk factors associated with cognitive function, although findings from population-based studies spanning the full adult age range are lacking. This study aimed to investigate associations between psychiatric symptomatology, psychotropic medication use and cognitive function in a population-based sample of men.

METHODS

Data for 537 men were drawn from the Geelong Osteoporosis Study. Cognitive function (psychomotor function, attention, working memory and visual learning) was determined using the Cog-State Brief Battery. Current depressive and anxiety symptomatology was determined using the Hospital Anxiety and Depression Scale, and psychotropic medication use was self-reported. Linear regression models were developed to determine associations between psychiatric symptomatology and psychotropic medication use with each cognitive measure.

RESULTS

Depressive symptomatology was associated with lower overall cognitive function (b-0.037 ± 0.010, η2 = 0.025, p < 0.001), psychomotor function (b 0.006 ± 0.002, η2 = 0.028 p < 0.001) and attention (b 0.004 ± 0.001, η2 = 0.021, p < 0.001), whereas psychotropic use was associated with lower overall cognitive function (b - 0.174 ± 0.075, η2 = 0.010, p = 0.021), attention (b 0.017 ± 0.008, η2 = 0.008, p = 0.038 and working memory (b 0.031 ± 0.012, η2 = 0.010, p = 0.010). Anticonvulsant use was associated with lower overall cognitive function (b - 0.723 ± 0.172, η2 = 0.032, p < 0.001), attention (b 0.065 ± 0.018, η2 = 0.029, p < 0.001) and working memory (b 0.088 ± 0.026, η2 = 0.022, p < 0.001). All relationships were found to have a small effect. There were no significant associations between anxiety symptomatology and antidepressant and anxiolytic use with any of the cognitive domains.

CONCLUSION

Depressive symptomatology and anticonvulsant use were associated with lower cognitive function. Understanding the underlying mechanisms involved in these relationships can advance knowledge on the heterogeneity in cognitive ageing and aid in prevention initiatives.

Neural correlates of episodic memory decline following electroconvulsive therapy: An exploratory functional magnetic resonance imaging study

BACKGROUND

Electroconvulsive therapy (ECT) is an efficient and rapid-acting treatment indicated for severe depressive disorders. While ECT is commonly accompanied by transient memory decline, the brain mechanisms underlying these side effects remain unclear.

AIMS

In this exploratory functional magnetic resonance (fMRI) study, we aimed to compare effects of ECT versus pharmacological treatment on neural response during episodic memory encoding in patients with affective disorders.

METHODS

This study included 32 ECT-treated patients (major depressive disorder (MDD), n = 23; bipolar depression, n = 9) and 40 partially remitted patients in pharmacological treatment (MDD, n = 24; bipolar disorder, n = 16). Participants underwent neuropsychological assessment, a strategic picture encoding fMRI scan paradigm, and mood rating. The ECT group was assessed before ECT (pre-ECT) and 3 days after their eighth ECT session (post-ECT).

RESULTS

Groups were comparable on age, gender, and educational years (ps ⩾ 0.05). Within-group analyses revealed a selective reduction in verbal learning and episodic memory pre- to post-ECT (p = 0.012) but no decline in global cognitive performance (p = 0.3). Functional magnetic resonance imaging analyses adjusted for mood symptoms revealed greater activity in ECT-treated patients than pharmacologically treated No-ECT patients across left precentral gyrus (PCG), right dorsomedial prefrontal cortex (dmPFC), and left middle frontal gyrus (MFG). In ECT-treated patients, greater decline in verbal learning and memory performance from pre- to post-ECT correlated with higher PCG response (r = -0.46, p = 0.008), but not with dmPFC or MFG activity (ps ⩾ 0.1), post-ECT.

CONCLUSIONS

Episodic memory decline was related to greater neural activity in the left PCG, but unrelated to increased dmPFC and MFG activity, immediately after ECT.

Comparative analysis of anticholinergic burden scales to explain iatrogenic cognitive impairment and self-reported side effects in the euthymic phase of bipolar disorders: Results from the FACE-BD cohort

Bipolar disorders (BD) are characterized by cognitive impairment during the euthymic phase, to which treatments can contribute. The anticholinergic properties of medications, i.e., the ability of a treatment to inhibit cholinergic receptors, are associated with cognitive impairment in elderly patients and people with schizophrenia but this association has not been well characterized in individuals with remitted BD. Moreover, the validity of only one anticholinergic burden scale designed to assess the anticholinergic load of medications has been tested in BD. In a literature review, we identified 31 existing scales. We first measured the associations between 27 out of the 31 scales and objective cognitive impairment in bivariable regressions. We then adjusted the bivariable models with covariates: the scales significantly associated with cognitive impairment in bivariable and multiple logistic regressions were defined as having good concurrent validity to assess cognitive impairment. In a sample of 2,031 individuals with euthymic BD evaluated with a neuropsychological battery, two scales had good concurrent validity to assess cognitive impairment, whereas chlorpromazine equivalents, lorazepam equivalents, the number of antipsychotics, or the number of treatments had not. Finally, similar analyses with subjective anticholinergic side-effects as outcome variables reported 14 scales with good concurrent validity to assess self-reported peripheral anticholinergic side-effects and 13 to assess self-reported central anticholinergic side-effects. Thus, we identified valid scales to monitor the anticholinergic burden in BD, which may be useful in estimating iatrogenic cognitive impairment in studies investigating cognition in BD.

Associations between aberrant working memory-related neural activity and cognitive impairments in somatically healthy, remitted patients with mood disorders

BACKGROUND

Persistent cognitive deficits are prevalent in patients with bipolar disorder (BD) and unipolar disorder (UD), but treatments effectively targeting cognition in these mood disorders are lacking. This is partly due to poor insight into the neuronal underpinnings of cognitive deficits.

METHODS

The aim of this functional magnetic resonance imaging (fMRI) study was to investigate the neuronal underpinnings of working memory (WM)-related deficits in somatically healthy, remitted patients with BD or UD (n = 66) with cognitive and functional impairments compared to 38 healthy controls (HC). The participants underwent neuropsychological testing and fMRI, while performing a visuospatial and a verbal N-back WM paradigm.

RESULTS

Relative to HC, patients exhibited hypo-activity across dorsolateral prefrontal cortex as well as frontal and parietal nodes of the cognitive control network (CCN) and hyper-activity in left orbitofrontal cortex within the default mode network (DMN) during both visuospatial and verbal WM performance. Verbal WM-related response in the left posterior superior frontal gyrus (SFG) within CCN was lower in patients and correlated positively with out-of-scanner executive function performance across all participants.

CONCLUSIONS

Our findings suggest that cognitive impairments across BD and UD are associated with insufficient recruitment of task-relevant regions in the CCN and down-regulation of task-irrelevant orbitofrontal activity within the DMN during task performance. Specifically, a lower recruitment of the left posterior SFG within CCN during verbal WM was associated with lower cognitive performance.

Better than expected: the gap between self-reported and objective measures of cognitive performance in remitted bipolar disorder

Background

Studies comparing objective and self-reported cognitive functioning as well as influencing factors in individuals with remitted bipolar disorder are scarce and contradictory.

Methods

The aim of this study was to compare executive functioning and other objective and self-reported cognitive impairment between 26 individuals with remitted bipolar disorder (15 BD I) and 24 healthy controls using a cross-sectional design. Executive functions were measured by the TAP Go/No-go subtest as well as the Stroop Task. Self-rated functioning was assessed using the Attention Deficit Experience Questionnaire. In addition, possible predictors of self-reported and objective cognitive functioning were examined to perform regression analyses.

Results

Individuals with remitted bipolar disorder did not differ significantly in executive functions or other objective cognitive domains from the healthy control group, but showed a significantly lower level of self-reported cognitive functioning and self-esteem. While self-esteem was the strongest predictor in healthy controls for self-reported cognitive functioning, severity of illness and subthreshold depressive mood were the most important predictors in individuals with remitted bipolar disorder.

Conclusion

The results once again demonstrate the cognitive heterogeneity in bipolar disorder. In the treatment of cognitive deficits, factors such as subthreshold depressive symptomatology and self-esteem should be focused on in addition to cognitive training in remitted patients.

Neurocognitive Deficits in Recently Diagnosed Young Remitted Bipolar I Disorder and At-Risk Subjects: Potential Endophenotypes?

Background

Neurocognitive deficits have been reported consistently in euthymic bipolar disorder (BD) across studies. Endophenotype potential of such deficits have been reported in a few studies. However, data from the Indian subcontinent is sparse, and no studies had a sample (patients and high-risk group) aged 20-25 years, which is the actual risk period for developing BD. We studied cognitive deficits, as a potential endophenotype for BD, in recently diagnosed BD (FEM-first episode mania) in remission, young unaffected first-degree relatives (HR) of patients with BD, and healthy controls (HC).

Methods

Cross-sectional study design using convenient sampling was employed. We recruited FEM (n = 25), HR (n = 25), and age-matched HC (n = 25) between 18 and 30 years. All HR subjects were <25 years of age, which is the period of vulnerability for BD. All the groups were screened using MINI Version 6. Neurocognitive assessments were done using the NIMHANS neuropsychology battery. The cognitive domains assessed were processing speed, attention, working memory, executive functions, and visual and verbal memory.

Results

The three groups were comparable in age and sex (all P > 0.06). The mean (SD) age of the FEM subjects was 23.7 (3.47) years, and the mean duration of illness was 5.92 (2.94) months. Compared to the HC group, the FEM group performed poorly on multiple cognitive domains (all P < 0.05). Performance of the HR group was comparable to the FEM group, but they showed significantly poorer performance compared to HC on the verbal fluency test-controlled oral word association (COWA, F = 12.36, P = 0.001), and the visual learning and memory test-complex figure test-immediate recall (CFT-IR, F = 8.10 and p = 0.001).

Conclusions

Cognition is impaired very early in the course of BD. Visual memory and executive function (verbal fluency) have endophenotypic potential. These findings are particularly important given that the HR group were still within the vulnerable period to develop BD. These findings imply a tremendous potential for early diagnosis and prevention by early interventions in BD.

An update on potential pharmacotherapies for cognitive impairment in bipolar disorder

INTRODUCTION

Cognitive impairment is a core feature of bipolar disorder (BD) that impedes recovery by preventing the return to optimal socio-occupational functioning and reducing quality of life. Presently, there are no efficacious treatments for cognitive impairment in BD, but many pharmacological interventions are being considered as they have the potential to target the underlying pathophysiology of the disorder.

AREAS COVERED

This review summarizes the available evidence for pharmacological interventions for cognitive impairment in bipolar disorder. We searched PubMed, MedLine, and PsycInfo from inception to December 1^st, 2022. Traditional treatments, such as lithium, anticonvulsants (lamotrigine), antipsychotics (aripiprazole, asenapine, cariprazine, lurasidone, and olanzapine), antidepressants (vortioxetine, fluoxetine, and tianeptine) and psychostimulants (modafinil), and emerging interventions, such as acetylcholinesterase inhibitors (galantamine and donepezil), dopamine agonists (pramipexole), erythropoietin, glucocorticoid receptor antagonists (mifepristone), immune modulators (infliximab, minocycline and doxycycline), ketamine, metabolic agents (insulin, metformin, and liraglutide), probiotic supplements, and Withania somnifera are discussed.

EXPERT OPINION

The investigation of interventions for cognitive impairment in BD is a relatively under-researched area. In the past, methodological pitfalls in BD cognition trials have also been a critical limiting factor. Expanding on the existing literature and identifying novel pharmacological and non-pharmacological treatments for cognitive impairment in BD should be a priority.

[Effects of lithium, valproic acid, carbamazepine and antipsychotic agents on cognition in bipolar disorders-A systematic review]

BACKGROUND

Until now the long-term consequences of the medical treatment for bipolar disorder have barely been examined, especially the consequences with respect to cognitive impairment and dementia. Some studies show signs that some treatment options have a better effect on the brain than others. This review summarizes the current state of research.

OBJECTIVE

The effects of long-term consequences of lithium, valproic acid, carbamazepine and antipsychotic agents on the development of dementia or cognitive impairments in patients with bipolar disorder were investigated.

METHODS

A systematic literature search was carried out in the PubMed data base from May to July 2022.

RESULTS

The majority of studies showed that lithium has a neuroprotective effect and can lower the risk of developing dementia, whereas an increased risk was found in patients taking valproic acid. There are only very few studies that deal with antipsychotic medication and the long-term consequences concerning dementia.

CONCLUSION

Lithium should be recommended for the long-term treatment of bipolar disorder. Valproic acid should not or carefully be used as it can affect the risk of developing dementia. With respect to antipsychotics there is no recommendation as more studies are needed to evaluate the long-term consequences.

The trajectory of emotional and non-emotional cognitive function in newly diagnosed patients with bipolar disorder and their unaffected relatives: A 16-month follow-up study

Cognitive impairments are evident in remitted patients with bipolar disorder (BD) and their unaffected relatives (UR) compared to healthy controls (HC). However, the temporal course of cognition, and whether cognition is marked by neuroprogressive changes, remain unclear. In a large prospective study of newly diagnosed patients with BD, we assessed patients with BD (n = 266), UR (n = 105) and HC (n = 190) using an extensive cognitive battery of non-emotional and emotional cognition at baseline and 16-months follow-up. Cognitive change across groups was examined with linear mixed-model analyses. Results showed no evidence of trajectory differences between patients with BD, UR, and HC in neurocognition and emotional cognition (ps≥.10). Patients with BD showed stable impairments in global neurocognitive functioning over time, as well as within the domains of 'working memory and executive function' and 'attention and psychomotor speed', compared to HC. Patients who relapsed during the follow-up time were less successful at down-regulating emotions in positive social scenarios compared to HC. Unaffected relatives also displayed stable deficits in 'working memory and executive function' over time, with performance at intermediate levels between BD probands and HC. Finally, poorer neurocognition and positive emotion regulation were associated with more subsyndromal symptoms and functional impairments. In conclusion, we found no evidence of a neuroprogressive origin of cognitive impairments in the newly diagnosed BD or in their UR. Patients' and UR's impairments in working memory and executive function may reflect a stable cognitive trait-marker of familial risk. Difficulties with positive emotion regulation may be associated with illness progression in BD.

MICEmi: A method to identify cognitive endophenotypes of mental illnesses

BACKGROUND

Characterizing neurocognitive endophenotypes of mental illnesses (MIs) could be useful for identifying at-risk individuals, increasing early diagnosis, improving disease subtyping, and proposing therapeutic strategies to reduce the negative effects of the symptoms, in addition to serving as a scientific basis to unravel the physiopathology of the disease. However, a standardized algorithm to determine cognitive endophenotypes has not yet been developed. The main objective of this study was to present a method for the identification of endophenotypes in MI research.

METHODS

For this purpose, a 14-expert working group used a scoping review methodology and designed a method that includes a scoring template with five criteria and indicators, a strategy for their verification, and a decision tree.

CONCLUSIONS

This work is ongoing since it is necessary to obtain external validation of the applicability of the method in future research.

Gut Microbial Dysbiosis and Cognitive Impairment in Bipolar Disorder: Current Evidence

Recent studies have reported that the gut microbiota influences mood and cognitive function through the gut-brain axis, which is involved in the pathophysiology of neurocognitive and mental disorders, including Parkinson’s disease, Alzheimer’s disease, and schizophrenia. These disorders have similar pathophysiology to that of cognitive dysfunction in bipolar disorder (BD), including neuroinflammation and dysregulation of various neurotransmitters (i.e., serotonin and dopamine). There is also emerging evidence of alterations in the gut microbial composition of patients with BD, suggesting that gut microbial dysbiosis contributes to disease progression and cognitive impairment in BD. Therefore, microbiota-centered treatment might be an effective adjuvant therapy for BD-related cognitive impairment. Given that studies focusing on connections between the gut microbiota and BD-related cognitive impairment are lagging behind those on other neurocognitive disorders, this review sought to explore the potential mechanisms of how gut microbial dysbiosis affects cognitive function in BD and identify potential microbiota-centered treatment.

Randomised controlled cognition trials in remitted patients with mood disorders published between 2015 and 2021: A systematic review by the International Society for Bipolar Disorders Targeting Cognition Task Force

BACKGROUND

Cognitive impairments are an emerging treatment target in mood disorders, but currently there are no evidence-based pro-cognitive treatments indicated for patients in remission. With this systematic review of randomised controlled trials (RCTs), the International Society for Bipolar Disorders (ISBD) Targeting Cognition Task force provides an update of the most promising treatments and methodological recommendations.

METHODS

The review included RCTs of candidate pro-cognitive interventions in fully or partially remitted patients with major depressive disorder or bipolar disorder. We followed the procedures of the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) 2020 statement. Searches were conducted on PubMed/MEDLINE, PsycInfo, EMBASE and Cochrane Library from January 2015, when two prior systematic reviews were conducted, until February 2021. Two independent authors reviewed the studies with the Revised Cochrane Collaboration's Risk of Bias tool for Randomised trials.

RESULTS

We identified 16 RCTs (N = 859) investigating cognitive remediation (CR; k = 6; N = 311), direct current or repetitive magnetic stimulation (k = 3; N = 127), or pharmacological interventions (k = 7; N = 421). CR showed most consistent cognitive benefits, with two trials showing improvements on primary outcomes. Neuromodulatory interventions revealed no clear efficacy. Among pharmacological interventions, modafinil and lurasidone showed early positive results. Sources of bias included small samples, lack of pre-screening for objective cognitive impairment, no primary outcome and no information on allocation sequence masking.

CONCLUSIONS

Evidence for pro-cognitive treatments in mood disorders is emerging. Recommendations are to increase sample sizes, pre-screen for impairment in targeted domain(s), select one primary outcome, aid transfer to real-world functioning, investigate multimodal interventions and include neuroimaging.

Driving performance of euthymic outpatients with bipolar disorder undergoing real-world pharmacotherapy

OBJECTIVE

Medications for the treatment of bipolar disorder (BD) could affect patients' cognitive function. Patients with BD present with neurocognitive impairment even in a remission state. Little research is available on the daily functioning, especially driving performance, of stable outpatients with BD under pharmacological treatment.

METHODS

In total, 58 euthymic outpatients with BD undergoing real-world pharmacotherapy and 80 sex- and age-matched healthy controls (HCs) were enrolled. Three driving tasks using a driving simulator-road-tracking, car-following, and harsh-braking-and three cognitive tasks-Continuous Performance Test, Wisconsin Card Sorting Test, and Trail-Making Test-were evaluated. Symptom assessment scales-Young Mania Rating Scale, Structured Interview Guide for the Hamilton Depression Rating Scale, Beck Depression Inventory-II, Social Adaptation Self-evaluation Scale, and Stanford Sleepiness Scale-were also completed.

RESULTS

Car-following and road-tracking performance were significantly impaired in patients with BD compared with HCs after adjusting for demographic variables, but these performances generally overlapped. Broad neurocognitive functions were significantly lower in the patients with BD compared to HCs, but car-following performance was significantly negatively correlated with sustained attention only. Although most patients received multiple medications rather than monotherapy, no relationship between prescriptions and driving performance was found.

CONCLUSION

Euthymic patients with BD under steady-state pharmacotherapy had impaired driving performance compared with HCs, but the overlapping distributions of driving performance suggested that driving performance is not always deteriorated in patients with BD. Therefore, attentional function may be a useful clinical feature for judging driving aptitude in patients with BD.

Neuronal underpinnings of cognitive impairment in bipolar disorder: A large data-driven functional magnetic resonance imaging study

OBJECTIVES

Cognitive impairment occurs in approximately 50% of remitted patients with bipolar disorder (BD). However, there exists no treatment with replicated and robust efficacy on cognition in BD. This is partially due to limited insight into the neuronal underpinnings of cognitive impairment in these patients. This is the first study to investigate neuronal underpinnings of cognitive impairment in a large functional magnetic resonance imaging (fMRI) dataset comparing neural activity patterns between distinct neurocognitive subgroups of partially or fully remitted patients with BD.

METHODS

Patients (n = 153) and healthy controls (HC) (n = 52) underwent neuropsychological assessment and fMRI, during which they performed a verbal N-back working memory (WM) task. Based on hierarchical cluster analysis of neuropsychological test performance, patients were grouped into one of two neurocognitive subgroups (cognitively impaired, n = 91; cognitively normal compared to HC, n = 62) that were compared on WM-related neural activity.

RESULTS

Cognitively impaired patients displayed WM-related hypo-activity in left dorsolateral prefrontal cortex and frontal and parietal regions within a cognitive control network (CCN) as well as hyper-activity in the default mode network (DMN) compared to cognitively normal patients. In contrast, cognitively normal patients only exhibited hypo-activity within a small cluster in the superior frontal gyrus relative to HC.

CONCLUSIONS

Cognitive impairment in BD seems to originate from a failure to recruit key regions in the CCN and to suppress task-irrelevant DMN activity during cognitive performance. These results highlight modulation of aberrant dorsal prefrontal and DMN activity as a putative target for pro-cognitive treatment in BD.

Fenofibrate ameliorates olanzapine's side effects without altering its central effect: emphasis on FGF-21-adiponectin axis

The present work was designed to investigate whether fenofibrate could ameliorate olanzapine deleterious effect on insulin resistance via its effect on fibroblast growth factor-21 (FGF-21)-adiponectin axis without affecting olanzapine antipsychotic effect in postweaning socially isolated reared female rats. Treatment with olanzapine (6 mg/kg, intraperitoneally) or fenofibrate (100 mg/kg, orally) have been started 5 weeks after isolation, then behavioral tests, hippocampal content of neurotransmitters, and brain-derived neurotrophic factor (BDNF) were assessed. Moreover, insulin resistance, lipid profile, FGF-21, adiponectin, inflammatory, and oxidative stress markers of adipose tissue were assessed. Treatment of isolated-reared animals with olanzapine, or fenofibrate significantly ameliorated the behavioral and biochemical changes induced by postweaning social isolation. Co-treatment showed additive effects in improving hippocampal BDNF level. Besides, fenofibrate reduced the elevation in weight gain, adiposity index, insulin resistance, lipid profile, and FGF-21 level induced by olanzapine treatment. Also, fenofibrate increased adiponectin level which was reduced upon olanzapine treatment. Moreover, fenofibrate improved both adipose tissue oxidative stress and inflammatory markers elevation as a result of olanzapine treatment. Fenofibrate could ameliorate olanzapine-induced insulin resistance without affecting its central effect in isolated reared rats via its action on FGF-21-adiponectin axis.

Effect of Pharmacological and Neurostimulation Interventions for Cognitive Domains in Patients with Bipolar Disorder: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

The priority of interventions to alleviate cognitive deficits in patients with bipolar disorder (BD) is inconclusive. We systematically evaluate the efficacy of pharmacological or neurostimulation interventions for cognitive function in BD through a network meta-analysis.

METHODS

The PubMed, PsycINFO, Embase, and Cochrane Library databases were searched from database inception to September 30, 2021. Following PRISMA guidelines, all eligible studies were randomized controlled trials of adult bipolar patients that provided detailed cognitive outcomes. Studies were excluded if participants limited to comorbid substance use disorder or the intervention was a psychotherapy. Network meta-analysis comparing different interventions was conducted for 8 cognitive domains. Partially ordered set with Hasse diagram was used to resolve conflicting rankings between outcomes. The study was preregistered on PROSPERO database (CRD42020152044).

RESULTS

Total 21 RCTs including 42 tests for assessing intervention effects on cognition were retrieved. Adjunctive erythropoietin (SMD = 0.61, 95% CI = 0.00-1.23), Withania somnifera (SMD = 0.58, 95% CI = 0.03-1.13), and galantamine (SMD = 1.22, 95% CI = 0.10-2.35) was more beneficial for attention, working memory, and verbal learning in euthymic BD patients than treatment as usual, respectively. Hasse diagram suggested ranking of choice when multiple domains were combined.

CONCLUSION

Considerable variability in measurements of cognitive domains in BD was observed, and no intervention resulted in superior benefits across all domains. We suggested interventions priority can be tailored according to individual patients' cognitive deficits. As current findings from relatively small and heterogeneous dataset, future trials with consensus should be applied for building further evidence.

Assessment of the neuronal underpinnings of cognitive impairment in bipolar disorder with a picture encoding paradigm and methodological lessons learnt

BACKGROUND

Mood disorders are often associated with persistent cognitive impairments. However, pro-cognitive treatments are essentially lacking. This is partially because of poor insight into the neurocircuitry abnormalities underlying these deficits and their change with illness progression.

AIMS

This functional magnetic resonance imaging (fMRI) study investigates the neuronal underpinnings of cognitive impairments and neuronal change after mood episodes in remitted patients with bipolar disorder (BD) using a hippocampus-based picture encoding paradigm.

METHODS

Remitted patients with BD (n=153) and healthy controls (n=52) were assessed with neuropsychological tests and underwent fMRI while performing a strategic picture encoding task. A subgroup of patients (n=43) were rescanned after 16 months. We conducted data-driven hierarchical cluster analysis of patients' neuropsychological data and compared encoding-related neuronal activity between the resulting neurocognitive subgroups. For patients with follow-up data, effects of mood episodes were assessed by comparing encoding-related neuronal activity change in BD patients with and without episode(s).

RESULTS

Two neurocognitive subgroups were revealed: 91 patients displayed cognitive impairments while 62 patients were cognitively normal. No neuronal activity differences were observed between neurocognitive subgroups within the dorsal cognitive control network or hippocampus. However, exploratory whole-brain analysis revealed lower activity within a small region of middle temporal gyrus in impaired patients, which significantly correlated with poorer neuropsychological performance. No changes were observed in encoding-related neuronal activity or picture recall accuracy with the occurrence of mood episode(s) during the follow-up period.

CONCLUSION

Memory encoding fMRI paradigms may not capture the neuronal underpinnings of cognitive impairment or effects of mood episodes.

Cognitive impairment and consumption of mental healthcare resources in outpatients with bipolar disorder

Cognitive dysfunction is a major predictor of functional outcomes, and loss of occupational functioning is usually linked with a higher cost of illness. However, the association between cognitive impairment and consumption of health resources has not been studied in bipolar disorder to date. This study aims to examine this relationship. This is an observational, retrospective study of a representative sample of euthymic outpatients between 18 and 55 years, fulfilling DSM 5 criteria for bipolar disorder and recruited at a catchment area in Spain. Cognitive performance was screened with the Spanish version of the Screen for Cognitive Impairment in Psychiatry (SCIP-S), and several variables of health resources consumption during the previous year were registered. A total of 72 patients were assessed. Cognitive impairment according to the SCIP-S was significantly associated with the number of scheduled clinical appointments (p < 0.005) and hospital admissions (p < 0.04) but not with other health resources consumption variables. These results need to be interpreted with caution given that neither a control group nor a comprehensive, objective neuropsychological battery were used. However, despite these limitations, this study shows that in euthymic outpatients with bipolar disorder, those with suspected cognitive impairment had consumed a higher number of health resources over the previous year. These preliminary results may foster similar studies on the relationship between mental healthcare resource use and cognitive dysfunction in bipolar disorder and other psychiatric disorders.

The functional impairment of different subtypes and occupational states in euthymic patients with bipolar disorder

BACKGROUND

The aim was to explore the associations between clinical symptoms, demographic variables, social and neurocognitive functioning in euthymic patients with bipolar disorder (BD) stratified by subgroups of DSM-IV BD (type I (BD-I) and type II (BD-II)) and occupational status (employed/unemployed), and to highlight the significance of occupational status when assessing social and neurocognitive functioning in euthymic BD patients.

METHODS

A total of 81 euthymic BD patients were participated in the study. The severity of the depressive and manic/hypomanic symptoms was measured using the 17-item Hamilton Depression Rating Scale (HDRS-17) and the Young Mania Rating Scale (YMRS), respectively. Social functioning and neurocognitive functioning were evaluated by the Functioning Assessment Short Test (FAST) and neurocognitive measures, respectively.

RESULTS

Employed BD patients displayed greater social functioning (autonomy, occupational functioning, interpersonal relationship domain) and better verbal learning performance and speed of processing than unemployed BD patients. The correlation between neurocognitive functioning and social functioning was stronger in the employed group than in the unemployed group. There were no significant differences in neurocognitive and social functioning between the BD-I and BD-II groups, and the correlation between neurocognitive functioning and social functioning was similar between the BD-I and BD-II groups.

CONCLUSION

Employed BD patients may present greater occupational functioning and interpersonal relationships, as well as better verbal learning performance and speed of processing.

Efficacy and safety of lamotrigine in the treatment of bipolar disorder across the lifespan: a systematic review

BACKGROUND

Bipolar disorder (BD) is a cyclic mood disorder characterised by alternating episodes of mania/hypomania and depression interspersed with euthymic periods. Lamotrigine (LTG) demonstrated some mood improvement in patients treated for epilepsy, leading to clinical studies in patients with BD and its eventual introduction as maintenance therapy for the prevention of depressive relapse in euthymic patients. Most current clinical guidelines include LTG as a recommended treatment option for the maintenance phase in adult BD, consistent with its global licencing status.

AIMS

To review the evidence for the efficacy and safety of LTG in the treatment of all phases of BD.

METHODS

PubMed was searched for double-blind, randomised, placebo-controlled trials using the keywords: LTG, Lamictal, 'bipolar disorder', 'bipolar affective disorder', 'bipolar I', 'bipolar II', cyclothymia, mania, manic, depression, depressive, 'randomised controlled trial', 'randomised trial', RCT and 'placebo-controlled' and corresponding MeSH terms. Eligible articles published in English were reviewed.

RESULTS

Thirteen studies were identified. The strongest evidence supports utility in the prevention of recurrence and relapse, particularly depressive relapse, in stabilised patients. Some evidence suggests efficacy in acute bipolar depression, but findings are inconsistent. There is little or no strong evidence in support of efficacy in acute mania, unipolar depression, or rapid-cycling BD. Few controlled trials have evaluated LTG in bipolar II or in paediatric patients. Indications for safety, tolerability and patient acceptability are relatively favourable, provided there is slow dose escalation to reduce the probability of skin rash.

CONCLUSION

On the balance of efficacy and tolerability, LTG might be considered a first-line drug for BD, except for acute manic episodes or where rapid symptom control is required. In terms of efficacy alone, however, the evidence favours other medications.

Diet and Neurocognition in Mood Disorders - An Overview of the Overlooked

Bipolar disorder and major depression are associated with significant disability, morbidity, and reduced life expectancy. People with mood disorders have shown higher ratios of unhealthy lifestyle choices, including poor diet quality and suboptimal nutrition. Diet and nutrition impact on brain /mental health, but cognitive outcomes have been less researched in psychiatric disorders. Neurocognitive dysfunction is a major driver of social dysfunction and a therapeutic target in mood disorders, although effective cognitive-enhancers are currently lacking. This narrative review aimed to assess the potential cognitive benefits of dietary and nutritional interventions in subjects diagnosed with mood disorders. Eight clinical trials with nutrients were identified, whereas none involved dietary interventions. Efficacy to improve select cognitive deficits has been reported, but results are either preliminary or inconsistent. Methodological recommendations for future cognition trials in the field are advanced. Current evidence and future views are discussed from the perspectives of precision medicine, clinical staging, nutritional psychiatry, and the brain-gut-microbiota axis.

Subjective cognitive dysfunction in patients with bipolar disorder: The prevalence, related factors and effects on predicting psychosocial functioning and suicidal ideation

Persistent cognitive deficits are prevalent during all stages of bipolar disorder (BD). However, few studies have examined subjective cognitive complaints in patients with BD. This study aimed to investigate the prevalence and relevant factors of subjective cognitive functioning and its potential effects on predicting psychosocial functioning and suicidal ideation in BD. Ninety-two patients with BD type I (including 42 depressed patients and 50 euthymic patients) and 60 healthy individuals were recruited for this study. All participants were assessed with a battery of neuropsychological tests examining attention and processing speed, visual memory, working memory and executive functions, as well as the Cognitive Complaints in Bipolar Disorder Rating Assessment, the Global Assessment of Functioning scale and the Beck Scale for Suicide Ideation. Bipolar patients exhibited worse subjective cognitive dysfunction compared with healthy individuals, and depressed patients expressed more cognitive complaints than euthymic bipolar patients. In bipolar group, psychosocial functioning, suicidal ideation and occupational status were the main relevant factors of subjective cognitive functioning. Subjective cognitive functioning could also predict psychosocial functioning and suicidal ideation. Depressive symptoms moderated the associations between objective cognitive functioning and suicidal ideation, but could not moderate the correlations between cognitive functioning and psychosocial functioning. These findings suggest that subjective cognitive assessment should be further emphasized in clinical practice.

Three-year longitudinal cognitive functioning in patients recently diagnosed with bipolar disorder

OBJECTIVE

The longitudinal course of neuropsychological functioning after the first manic episode in bipolar disorder is unknown. The present study evaluated cognitive change in bipolar disorder in the first 3 years after the initial manic episode.

METHODS

Ninety-one newly diagnosed patients with bipolar disorder and 61 demographically similar healthy participants received a neuropsychological evaluation assessing multiple cognitive domains at baseline, 1-year, and 3-year time points. Patients also received clinical assessments including mood ratings at all time points.

RESULTS

Patients showed deficits in all domains at baseline, but similar longitudinal trajectories across time relative to healthy participants in most cognitive domains. For processing speed, patients showed more gains than controls from baseline to 1 year, but these gains stabilized thereafter. Patients with alcohol/substance abuse showed an initial delay but subsequent recovery in executive functioning. Patients who discontinued antipsychotic treatment showed better cognitive outcomes in verbal memory.

CONCLUSION

Appropriately treated patients with bipolar disorder showed favorable cognitive outcome in the first 3 years after experiencing an initial manic episode, arguing against cognitive neuroprogression at this stage of the illness. Discontinuation of antipsychotic treatment may be associated with better cognitive outcomes, but clarification of the role of antipsychotics on cognitive functioning requires further investigation.

A focus on valproate and cognitive deficits in Bipolar Disorders: A mini-review: Special Section on "Translational and Neuroscience Studies in Affective Disorders" Section Editor, Maria Nobile MD, PhD

BACKGROUND

Cognitive deficits represent a core feature of Bipolar Disorder (BD), which seem to characterize this disorder regardless of the mood phase. However, the role of pharmacological treatment in determining cognitive alterations is still not clear. Indeed, although drugs improve cognition by targeting mood symptoms, they could also carry their own cognitive side effects. This is true especially for mood stabilizers as they are the most commonly prescribed drugs in patients affected by BD and they are usually administered also during euthymic phases.

METHODS

In this context, the present review aimed at summarizing the results of the studies evaluating the impact of valproate on cognitive functions in patients suffering from BD, as primary or secondary results. The inclusion criteria were met by ten studies. Specifically, we included one double-blind quasi-randomized study and nine cross-sectional or naturalistic studies, which a) used healthy subjects as control group (N = 1), b) compared valproate treated patients with healthy individuals and other treatments (N = 5), and c) compared valproate treated patients just with other treatments, with a specific focus on lithium (N = 3).

RESULTS

Overall the results suggested a negative effect of valproate on cognitive functions in chronically-treated patients affected by BD. Notably, it has been found that the working memory was the most affected cognitive domain.

LIMITATIONS

Few studies directly explored the effect of valproate on cognition in BD.

CONCLUSIONS

These findings seem to suggest that valproate might have a negative effect on cognitive functions, especially on working memory domain. However, the results should be taken cautiously since the limited number of available studies published so far. In conclusion, these evidences seem to point out that the possible cognitive side effects of pharmacological treatments should be carefully taken into account, especially in chronic patients.

The effects of cognitive reserve on predicting and moderating the cognitive and psychosocial functioning of patients with bipolar disorder

BACKGROUND

Cognitive reserve (CR) reflects the resilience of the brain to cope with neuropathological changes and minimize clinical manifestations. In the present study, we explore the association between CR and cognitive and psychosocial functioning, and examined the potential moderating role of CR in patients with bipolar disorder (BD).

METHODS

One hundred and twenty-five outpatients with BD type I and sixty healthy individuals were recruited. All participants were assessed with a neuropsychological battery examining attention and processing speed, working memory, visual memory and executive functioning, the Global Assessment of Functioning scale and the Cognitive Complaints in Bipolar Disorder Rating Assessment. Proxies for cognitive reserve included premorbid intelligence and educational level.

RESULTS

Patients with bipolar disorder presented with worse cognitive performance and psychosocial functioning than healthy controls. Multiple regression models revealed that educational level negatively associated with all assessed domain-specific cognition scores and premorbid intelligence predicted attention and processing speed and psychosocial functioning. Notably, premorbid intelligence significantly moderated the associations between the number of episodes (total, hypo/manic and depressed) and neurocognitive functioning, and the educational level also moderated the relationships between the numbers of hypo/manic and total episodes and subjective cognitive functioning.

CONCLUSIONS

Cognitive reserve contributes to functional outcomes in patients with BD and may emerge as a key factor contributing to the course and prognosis of patients with BD. In the future, cognitive reserve must be considered in both research and clinical interventions related to bipolar disorder.

Pharmacogenomic Characterization in Bipolar Spectrum Disorders

The holistic approach of personalized medicine, merging clinical and molecular characteristics to tailor the diagnostic and therapeutic path to each individual, is steadily spreading in clinical practice. Psychiatric disorders represent one of the most difficult diagnostic challenges, given their frequent mixed nature and intrinsic variability, as in bipolar disorders and depression. Patients misdiagnosed as depressed are often initially prescribed serotonergic antidepressants, a treatment that can exacerbate a previously unrecognized bipolar condition. Thanks to the use of the patient's genomic profile, it is possible to recognize such risk and at the same time characterize specific genetic assets specifically associated with bipolar spectrum disorder, as well as with the individual response to the various therapeutic options. This provides the basis for molecular diagnosis and the definition of pharmacogenomic profiles, thus guiding therapeutic choices and allowing a safer and more effective use of psychotropic drugs. Here, we report the pharmacogenomics state of the art in bipolar disorders and suggest an algorithm for therapeutic regimen choice.

Visual memory dysfunction as a neurocognitive endophenotype in bipolar disorder patients and their unaffected relatives. Evidence from a 5-year follow-up Valencia study

BACKGROUND

Scarce research has focused on Visual Memory (VM) deficits as a possible neurocognitive endophenotype of bipolar disorder (BD). The main aim of this longitudinal, family study with healthy controls was to explore whether VM dysfunction represents a neurocognitive endophenotype of BD.

METHODS

Assessment of VM by Rey-Osterrieth Complex Figure Test (ROCF) was carried out on a sample of 317 subjects, including 140 patients with BD, 60 unaffected first-degree relatives (BD-Rel), and 117 genetically-unrelated healthy controls (HC), on three occasions over a 5-year period (T1, T2, and T3). BD-Rel group scores were analyzed only at T1 and T2.

RESULTS

Performance of BD patients was significantly worse than the HC group (p < 0.01). Performance of BD-Rel was also significantly different from HC scores at T1 (p < 0.01) and T2 (p = 0.05), and showed an intermediate profile between the BD and HC groups. Only among BD patients, there were significant differences according to sex, with females performing worse than males (p = 0.03). Regarding other variables, education represented significant differences only in average scores of BD-Rel group (p = 0.01).

LIMITATIONS

Important attrition in BD-Rel group over time was detected, which precluded analysis at T3.

CONCLUSIONS

BD patients show significant deficits in VM that remain stable over time, even after controlling sociodemographic and clinical variables. Unaffected relatives also show stable deficits in VM. Accordingly, the deficit in VM could be considered a potential endophenotype of BD, which in turn may be useful as a predictor of the evolution of the disease. Further studies are needed to confirm these findings.

The associations between subjective and objective cognitive functioning across manic or hypomanic, depressed, and euthymic states in Chinese bipolar patients

BACKGROUND

Patients may present cognitive deficits during all stages of bipolar disorder (BD). Few studies have examined self-reported cognitive difficulties and its relation to neurocognitive dysfunction during symptomatic periods of BD. This study aimed to compare subjective cognitive functioning and explore associations between subjective and objective cognitive functioning across different BD clinical states, and investigate the predicting and moderating roles of mood symptoms.

METHODS

Subjective cognitive functioning (measured by Cognitive Complaints in Bipolar Disorder Rating Assessment, COBRA) and several domains of cognitive functioning (assessed by a neuropsychological battery), including executive functions, attention and processing speed, and visual memory, were examined in 48 hypomanic or manic patients, 42 depressed bipolar patients, 50 euthymic bipolar patients and 60 healthy comparisons.

RESULTS

All patients exhibited subjective and objective cognitive deficits in relation to healthy comparisons. There was a significant association between subjective and objective cognitive functioning in euthymic group, but the association was not significant in acute symptomatic groups, which could be moderated by depressive or manic symptoms in depressive or manic group, respectively. Subjective cognitive functioning was significantly correlated with mood symptoms, and the best predictor of subjective cognitive functioning was depressive symptoms.

LIMITATIONS

This was a cross-sectional study with a mixed sample of inpatients and outpatients. The medication effect was not adjusted.

CONCLUSIONS

The associations between subjective and objective cognitive dysfunction varied in clinical states, and mood symptoms moderated the associations. A neuropsychological test battery is required to substantiate actual cognitive dysfunction in clinical settings, irrespective of subjective cognitive deficits.

Social cognition in bipolar disorder: the role of sociodemographic, clinical, and neurocognitive variables in emotional intelligence

OBJECTIVE

The main aims of this study were to examine the differences in the Emotional Intelligence (EI), the emotional domain of social cognition (SC), between euthymic patients with bipolar disorder (BD) and healthy controls (HC) and to evaluate the contribution of sociodemographic, clinical, and neuropsychological variables to EI.

METHODS

We recruited 202 patients with BD and 50 HC. EI was evaluated using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). The sociodemographic, clinical, and neurocognitive variables that showed a significant association with EI were entered into hierarchical multiple regression analysis.

RESULTS

BD patients obtained significantly lower scores compared to HC in the Emotional Intelligence Quotient (EIQ) and in the Understanding Emotions branch score. The best fitting model for the variables associated with EI in the patients group was a linear combination of gender, estimated IQ, family history of affective diagnosis, and executive function. The model, including these previous variables, explained up to 27.6% of the observed variance (R²  = 0.276, F = 16.406, P < 0.001).

CONCLUSIONS

The identification of variables associated with deficit in EI, such as male gender, lower estimated IQ, family history of affective diagnosis. and lower executive function performance, may help in selecting treatment targets to improve SC, and especially EI, in patients with BD.

Clinical characteristics associated with the discrepancy between subjective and objective cognitive impairment in depression

BACKGROUND

Patients with unipolar disorder (UD) commonly experience cognitive dysfunction during symptomatic and remitted phases. However, it is not necessarily the patients with the greatest subjective complaints, who display the largest objectively-measured deficits on neuropsychological tests.

OBJECTIVE

This report investigated the demographic and clinical factors associated with the discrepancy between subjective and objective measures of cognition in two separate depressed patient populations in Denmark and New Zealand, respectively, using a new methodology.

METHODS

Data from 137 depressed patients and 103 healthy controls including neuropsychological test scores, self-reported cognitive difficulties, and ratings of mood were pooled from two studies conducted in Copenhagen, Denmark, and Christchurch, New Zealand, respectively. Cognitive discrepancy scores were calculated using a novel methodology, with positive values indicating disproportionately more subjective than objective difficulties (i.e., "sensitivity") and negative values indicating more objective than subjective impairments (i.e., "stoicism").

RESULTS

In the Danish partially remitted patient sample, greater 'sensitivity' was associated with more subsyndromal depression severity (standardized Beta (std. β )= 0.4, p < 0.01)), illness duration (std. β = 0.4, p < 0.01), and younger age (std. β = 0.6, p < 0.001). This association was replicated in the New Zealand sample of more symptomatic patients (p-values ≤ 0.05).

LIMITATIONS

The cross-sectional design hampered causal inferences. We had obtained different measures of objective and subjective cognition from the two studies.

CONCLUSIONS

Patients with more depressive symptoms and younger age overreported cognitive impairments across all illness states. The use of an objective cognition screener thus seems particularly relevant for these patients to assess whether subjective complaints are accompanied by measurable cognitive deficits.

GSK3β: a plausible mechanism of cognitive and hippocampal changes induced by erythropoietin treatment in mood disorders?

Mood disorders are associated with significant psychosocial and occupational disability. It is estimated that major depressive disorder (MDD) will become the second leading cause of disability worldwide by 2020. Existing pharmacological and psychological treatments are limited for targeting cognitive dysfunctions in mood disorders. However, growing evidence from human and animal studies has shown that treatment with erythropoietin (EPO) can improve cognitive function. A recent study involving EPO-treated patients with mood disorders showed that the neural basis for their cognitive improvements appeared to involve an increase in hippocampal volume. Molecular mechanisms underlying hippocampal changes have been proposed, including the activation of anti-apoptotic, antioxidant, pro-survival and anti-inflammatory signalling pathways. The aim of this review is to describe the potential importance of glycogen synthase kinase 3-beta (GSK3β) as a multi-potent molecular mechanism of EPO-induced hippocampal volume change in mood disorder patients. We first examine published associations between EPO administration, mood disorders, cognition and hippocampal volume. We then highlight evidence suggesting that GSK3β influences hippocampal volume in MDD patients, and how this could assist with targeting more precise treatments particularly for cognitive deficits in patients with mood disorders. We conclude by suggesting how this developing area of research can be further advanced, such as using pharmacogenetic studies of EPO treatment in patients with mood disorders.

Is cognitive impairment associated with antipsychotic dose and anticholinergic equivalent loads in first-episode psychosis?

BACKGROUND

Cognitive deficits are a core feature of early stages in schizophrenia. However, the extent to which antipsychotic (AP) have a deleterious effect on cognitive performance remains under debate. We aim to investigate whether anticholinergic loadings and dose of AP drugs in first episode of psychosis (FEP) in advanced phase of remission are associated with cognitive impairment and the differences between premorbid intellectual quotient (IQ) subgroups.

METHODS

Two hundred and sixty-six patients participated. The primary outcomes were cognitive dimensions, dopaminergic/anticholinergic load of AP [in chlorpromazine equivalents (Eq-CPZ) and the Anticholinergic Risk Scale (ARS), respectively].

RESULTS

Impairments in processing speed, verbal memory and global cognition were significantly associated with high Eq-CPZ and verbal impairment with high ARS score. Moreover, this effect was higher in the low IQ subgroup.

CONCLUSIONS

Clinicians should be aware of the potential cognitive impairment associated with AP in advanced remission FEP, particularly in lower premorbid IQ patients.

Affective versus non-affective first episode psychoses: A longitudinal study

OBJECTIVE

This study aimed to assess (1) whether there were clinical, neuropsychological and functional differences between and within affective and non-affective psychoses at baseline and two years-follow-up and (2) to explore clinical and neuropsychological predictors of psychosocial functioning in the whole sample.

METHOD

This is a subanalysis from a multicentre, naturalistic, longitudinal prospective study ('Phenotype-genotype and environmental interaction. Application of a predictive model in first psychotic episodes'). The sample consisted of 192 patients with a first psychotic episode (FEP): 142 with non-affective psychoses and 50 with affective psychoses. Student t-tests, paired t-tests, Pearson correlations, ANOVAs and regression analyses were performed.

RESULTS

At baseline, the groups differed in perseverative errors (WCST), Premorbid Adjustment Scale (PAS), family history of psychiatric disorder, negative (PANSS) and manic symptoms (YMRS). At two years follow-up, the groups differed in all the PANSS subscales and in depressive symptoms assessed by the MADRS. When the whole sample was considered, the regression model which best explained the estimated variance in functioning at follow-up (41%) was composed by PANSS total score and verbal fluency assessed by the FAS (COWAT).

CONCLUSIONS

We found clinical and neurocognitive differences at baseline which decreased in the follow-up. Reduced performances at baseline in executive functions in combination with symptom severity (PANSS) were predictors of FEP patients' poor functional outcome.

Psychometric properties of the Chinese version of the Functioning Assessment Short Test (FAST) in bipolar disorder

OBJECTIVES

Bipolar disorder (BD) is often associated with significant functional impairment. However, there is currently no valid and reliable instrument for this variable that is both brief and easy to administer in China. We thus aimed to evaluate the psychometric properties of the Chinese version of the Functioning Assessment Short Test (FAST) in Chinese adults with BD.

METHODS

In this sample of adult subjects, 176 with BD and 53 healthy controls were included. The Chinese version of the FAST, the Young Mania Rating Scale (YMRS), the 17-item Hamilton Depression Rating Scale (HDRS-17) and the Global Assessment Functioning (GAF) were administered, and the psychometric analysis of the FAST was conducted.

RESULTS

The internal consistency (Cronbach's alpha) was 0.89 and 0.88 for the FAST at the baseline and week 1, respectively. Four domains (occupational functioning, cognitive functioning, interpersonal relationship and financial issues) at baseline had high item-total correlations. The FAST assessments at baseline and week 1 were highly correlated, indicating high test-retest reliability. The FAST total score was strongly associated with GAF total scores at week 0 (r  = -0.952, p < 0.001), HDRS (r = 0.575, p < 0.001) and YRMS (r = 0.394, p < 0.001) and at week 1 (r  = -0.945, p < 0.001; r  = 0.582, p < 0.001; r  = 0.363, p < 0.001), respectively, suggesting high concurrent validity. The FAST showed four dimensional measurement properties in exploratory factor analysis at baseline.

CONCLUSIONS

The Chinese version of the FAST has satisfactory psychometric properties in terms of validity and reliability in Chinese adults with BD.

Neural correlates of improved recognition of happy faces after erythropoietin treatment in bipolar disorder

OBJECTIVE

Bipolar disorder is associated with impairments in social cognition including the recognition of happy faces. This is accompanied by imbalanced cortico-limbic response to emotional faces. We found that EPO improved the recognition of happy faces in patients with bipolar disorder. This randomized, controlled, longitudinal fMRI study explores the neuronal underpinnings of this effect.

METHOD

Forty-four patients with bipolar disorder in full or partial remission were randomized to eight weekly erythropoietin (EPO; 40 000 IU) or saline (NaCl 0.9%) infusions in a double-blind, parallel-group design. Participants underwent whole-brain fMRI at 3T, mood ratings and blood tests at baseline and week 14. During fMRI, participants viewed happy and fearful faces and performed a gender discrimination task.

RESULTS

Thirty-four patients had complete pre- and post-treatment fMRI data (EPO: N = 18, saline: N = 16). Erythropoietin vs. saline increased right superior frontal response to happy vs. fearful faces. This correlated with improved happiness recognition in the EPO group. Erythropoietin also enhanced gender discrimination accuracy for happy faces. These effects were not influenced by medication, mood, red blood cells or blood pressure.

CONCLUSIONS

Together with previous findings, the present observation suggests that increased dorsal prefrontal attention control is a common mechanism of EPO-associated improvements across several cognitive domains.

Canadian Network for Mood and Anxiety Treatments (CANMAT) and International Society for Bipolar Disorders (ISBD) 2018 guidelines for the management of patients with bipolar disorder

The Canadian Network for Mood and Anxiety Treatments (CANMAT) previously published treatment guidelines for bipolar disorder in 2005, along with international commentaries and subsequent updates in 2007, 2009, and 2013. The last two updates were published in collaboration with the International Society for Bipolar Disorders (ISBD). These 2018 CANMAT and ISBD Bipolar Treatment Guidelines represent the significant advances in the field since the last full edition was published in 2005, including updates to diagnosis and management as well as new research into pharmacological and psychological treatments. These advances have been translated into clear and easy to use recommendations for first, second, and third- line treatments, with consideration given to levels of evidence for efficacy, clinical support based on experience, and consensus ratings of safety, tolerability, and treatment-emergent switch risk. New to these guidelines, hierarchical rankings were created for first and second- line treatments recommended for acute mania, acute depression, and maintenance treatment in bipolar I disorder. Created by considering the impact of each treatment across all phases of illness, this hierarchy will further assist clinicians in making evidence-based treatment decisions. Lithium, quetiapine, divalproex, asenapine, aripiprazole, paliperidone, risperidone, and cariprazine alone or in combination are recommended as first-line treatments for acute mania. First-line options for bipolar I depression include quetiapine, lurasidone plus lithium or divalproex, lithium, lamotrigine, lurasidone, or adjunctive lamotrigine. While medications that have been shown to be effective for the acute phase should generally be continued for the maintenance phase in bipolar I disorder, there are some exceptions (such as with antidepressants); and available data suggest that lithium, quetiapine, divalproex, lamotrigine, asenapine, and aripiprazole monotherapy or combination treatments should be considered first-line for those initiating or switching treatment during the maintenance phase. In addition to addressing issues in bipolar I disorder, these guidelines also provide an overview of, and recommendations for, clinical management of bipolar II disorder, as well as advice on specific populations, such as women at various stages of the reproductive cycle, children and adolescents, and older adults. There are also discussions on the impact of specific psychiatric and medical comorbidities such as substance use, anxiety, and metabolic disorders. Finally, an overview of issues related to safety and monitoring is provided. The CANMAT and ISBD groups hope that these guidelines become a valuable tool for practitioners across the globe.

Cognitive dysfunction and metabolic comorbidities in mood disorders: A repurposing opportunity for glucagon-like peptide 1 receptor agonists?

Major depressive disorder and bipolar disorder are highly prevalent and disabling conditions. Cognition is considered a core domain of their psychopathology and a principle mediator of psychosocial impairment, disproportionately accounting for overall illness-associated costs. There are few interventions with replicated evidence of efficacy in treating cognitive deficits in mood disorders. Evidence also indicates that cognitive deficits are associated with obesity and involve significant impairment across multiple domains. Conversely, weight-loss interventions, such as physical exercise and bariatric surgery, have been shown to beneficially affect cognitive function. This convergent phenomenology suggests that currently available agents that target metabolic systems may also be capable of mitigating deficits in cognitive functions, and are, therefore, candidates for repurposing. The incretin glucagon-like peptide-1 (GLP-1) is a hormone secreted by intestinal epithelial cells. GLP-1 receptors (GLP-1R) are widely expressed in the central nervous system. Activation of GLP-1R leads to facilitation of glucose utilization and antiapoptotic effects in various organs. Pre-clinical trials have demonstrated significant neuroprotective effects of GLP-1, including protection from cell death, promotion of neuronal differentiation and proliferation; and facilitation of long-term potentiation. Liraglutide is a GLP-1R agonist that has been approved for the treatment of type 2 diabetes mellitus and obesity. Convergent preclinical and clinical evidence, including a proof-of-concept pilot study from group, has suggested that liraglutide may improve objective measures of cognitive function in adults with mood disorders. The safety and availability of GLP-1R agonists indicate that they are promising candidates for repurposing, and that they may be viable therapeutic options for mood disorders. This article is part of the Special Issue entitled 'Metabolic Impairment as Risk Factors for Neurodegenerative Disorders.'

Staging, Neurocognition and Social Functioning in Bipolar Disorder

Introduction: Bipolar disorder (BD) is associated with significant neurocognitive and functional impairment, which may progress across stages. The 'latent stage' of BD remains understudied. This cross-sectional study assessed staging, neurocognition and social functioning among BD patients and their healthy siblings. Methods: Four groups were included: euthymic type I BD patients in the early (n = 25) and late (n = 23) stages, their healthy siblings (latent stage; n = 23) and healthy controls (n = 21). All 92 subjects underwent a comprehensive neuropsychological battery of processing speed, verbal learning/memory, visual memory, working memory, verbal fluency, executive cognition, and motor speed. Social functioning was assessed using the FAST scale. Results: Siblings' social functioning was identical to that of controls, and significantly better than both early- (p < 0.005) and late- (p < 0.001) stage patients. Although all patients were strictly euthymic, those at late stages had a significantly worse social functioning than early-stage patients (p < 0.001). Compared to controls, increasingly greater neurocognitive dysfunction was observed across stages of BD (F = 1.59; p = 0.005). Healthy siblings' performance lied between those of controls and patients, with deficits in tasks of processing speed, executive attention, verbal memory/learning, and visual memory. Both early- and late-stage patients had a more severe and widespread dysfunction than siblings, with no significant differences between them. Conclusions: Genetic vulnerability to BD-I seems to be associated with neurocognitive impairments, whereas social dysfunction would be the result of the clinical phenotype. Staging models of BD should take into account these divergent findings in the latent stage.

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.

Cognitive Functioning in Euthymic Bipolar Patients on Monotherapy with Novel Antipsychotics or Mood Stabilizers

INTRODUCTION

Bipolar disorder is associated with cognitive dysfunction in several domains. Medication effect is a potential confounder that can only be statistically controlled in many studies. The cognitive profile in bipolar disorder during remission on maintenance antipsychotics or mood stabilizers medication has not been compared before.

METHODS

We compared the cognitive profile of bipolar disorder patients euthymic for 2 month or more on monotherapy with novel antipsychotics (AP) (n=16), lithium carbonate (Li) (n=25) or valproic acid (VPA; n=26). Forty-two individuals were assessed as controls. The cognitive battery included Wechsler Adult Intelligence Scale-Revised (WAIS-R) subtests, the Wechsler Memory Scale (WMS), and Wisconsin Card Sorting Test (WCST).

RESULTS

All three patient groups compared to controls performed poorly on the working memory and verbal memory tasks (F=3.59, df=3, p=0.02 for WAIS-R Arithmetic and F=123.64, df=3, p<0.01 for WMS Logical Memory). The differences remained significant after controlling for age. Across patients, the only significant difference was between the Li and AP groups in terms of working memory. The Li group performed better (F=3.59, df=2, p=0.02) and the difference survived correction for age and clinical features.

CONCLUSIONS

The findings of this study suggest that working memory impairment in bipolar patients on monotherapy with atypical AP, whereas verbal memory impairment might be related to bipolar disorder itself. Working memory might be a state marker, whereas verbal memory could be a trait marker of bipolar disorder. Atypical AP might have an adverse effect on cognition in bipolar disorder. These findings cannot be generalized to all bipolar patients, particularly the poor responders to monotherapy.

Bipolar Disorder and Cognitive Dysfunction: A Complex Link

The aim of this article was to describe the current evidence regarding phenomenon of cognitive functioning and dementia in bipolar disorder (BD). Cochrane Library and PubMed searches were conducted for relevant articles, chapters, and books published before 2016. Search terms used included "bipolar disorder," "cognitive dysfunction," and "dementia." At the end of the selection process, 159 studies were included in our qualitative synthesis. As result, cognitive impairments in BD have been previously considered as infrequent and limited to the affective episodes. Nowadays, there is evidence of stable and lasting cognitive dysfunctions in all phases of BD, including remission phase, particularly in the following domains: attention, memory, and executive functions. The cause of cognitive impairment in BD raises the question if it subtends a neurodevelopmental or a neurodegenerative process. Impaired cognitive functioning associated with BD may contribute significantly to functional disability, in addition to the distorted affective component usually emphasized.

Modulation of the N400 component in relation to hypomanic personality traits in a word meaning ambiguity resolution task

AIM

High levels of hypomanic personality traits have been associated with an increased risk of developing bipolar disorder (BD). Changes in semantic content, impaired verbal associations, abnormal prosody, and abnormal speed of language are core features of BD, and are thought to be related to semantic processing abnormalities. In the present study, we used event-related potentials to investigate the relation between semantic processing (N400 component) and hypomanic personality traits.

METHODS

We assessed 65 healthy young adults on the Hypomanic Personality Scale (HPS). Event-related potentials were recorded during a semantic ambiguity resolution task exploring semantic ambiguity (polysemous word ending a sentence) and congruency (target word semantically related to the sentence).

RESULTS

As expected, semantic ambiguity and congruency both elicited an N400 effect across our sample. Correlation analyses showed a significant positive relationship between the Social Vitality subscore of the HPS and N400 modulation in the frontal region of interest in the incongruent unambiguous condition, and in the frontocentral region of interest in the incongruent ambiguous condition.

CONCLUSION

We found differences in semantic processing (i.e., detection of incongruence and semantic inhibition) in individuals with higher Social Vitality subscores. In the light of the literature, we discuss the notion that a semantic processing impairment could be a potential marker of vulnerability to BD, and one that needs to be explored further in this clinical population.

Manual motor speed dysfunction as a neurocognitive endophenotype in euthymic bipolar disorder patients and their healthy relatives. Evidence from a 5-year follow-up study

BACKGROUND

Few studies have examined Manual Motor Speed (MMS) in bipolar disorder (BD). The aim of this longitudinal, family study was to explore whether dysfunctional MMS represents a neurocognitive endophenotype of BD.

METHODS

A sample of 291 subjects, including 131 BD patients, 77 healthy first-degree relatives (BD-Rel), and 83 genetically-unrelated healthy controls (HC), was assessed with the Finger-Tapping Test (FTT) on three occasions over a 5-year period. Dependence of FTT on participants´ age was removed by means of a lineal model of HC samples, while correcting simultaneously the time and learning effect. Differences between groups were evaluated with an ANOVA test.

RESULTS

The patients' performance was significantly worse than that of HC over time (p≤0.006), and these deficits remained when non-euthymic BD patients (n=9) were excluded from analysis. Some significant differences between BD patients and BD-Rel (p≤0.037) and between BD-Rel and HC (p≤0.033) were found, but they tended to disappear as time progressed (p≥0.057). Performance of the BD-Rel group was intermediate to that of BD and HC. Most sociodemographic and clinical variables did not affect these results in patients. (p≥0.1). However, treatment with carbamazepine and benzodiazepines may exert a iatrogenic effect on MMS performance (p≤0.006).

LIMITATIONS

Only right-handed subjects were included in this study. Substantial attrition over time was detected.

CONCLUSIONS

There were significant differences between the patients´ MMS performance and that of healthy relatives and controls, regardless of most clinical and sociodemographic variables. Dysfunctional MMS could be considered an endophenotype of BD. Further studies are needed to rule out possible iatrogenic effects of some psychopharmacological treatments.

Neuropsychological profiles of major depressive disorder and bipolar disorder during euthymia. A systematic literature review of comparative studies

Bipolar disorder and major depressive disorder have been shown to be associated with neurocognitive abnormalities during periods of clinical remission. However, at present, there is no consensus on whether these disorders have distinctive cognitive profiles. The aim of this study was to provide an updated systematic review of studies comparing neuropsychological functioning between bipolar disorder and major depressive disorder during remission. Main findings included the following: 1) no differences regarding performances in measures of attention and processing speed, executive functions and theory of mind were found between both patient groups and 2) regarding verbal memory, preliminary evidence points towards a more defective performance in patients with bipolar disorder than those with major depressive disorder. However, several variables with negative impact on cognition (medication status, age at onset, premorbid IQ, bipolar subtype, among others) were not adequately controlled in most studies. In conclusion, evidence from studies exploring neuropsychological profiles in bipolar disorder and major depressive disorder could not provide clues to differentiate these mood disorders. Larger studies with adequate control of confounding variables would be necessary to elucidate if the finding of more defective verbal memory performance in bipolar disorder is truly explained by distinct underlying mechanisms.

Neurocognitive performance, psychopathology and social functioning in individuals at high risk for schizophrenia or psychotic bipolar disorder

INTRODUCTION

Although cognitive deficits are consistent endophenotypes of schizophrenia and bipolar disorder, findings in psychotic bipolar disorder (BDP) are inconsistent. In this study we compared adult unaffected first-degree relatives of schizophrenia and BDP patients on cognition, psychopathology, social functioning and quality of life.

METHODS

Sixty-six unaffected first-degree relatives of schizophrenia patients (SUnR), 36 unaffected first-degree relatives of BDP patients (BDPUnR) and 102 controls participated in the study. Between-group differences were examined and Discriminant Function Analysis (DFA) predicted group membership.

RESULTS

Visual memory, control inhibition, working memory, cognitive flexibility and abstract reasoning were linearly impaired in the relatives' groups. Poorer verbal fluency and processing speed were evident only in the SUnR group. The SUnR group had higher depressive and somatization symptoms while the BDPUnR group had higher anxiety and lower social functioning compared with the controls. Individuals with superior cognition were more likely to be classified as controls; those with higher social functioning, prolonged processing speed and lower anxiety were more likely to be classified as SUnR.

LIMITATIONS

The relatives' sample is quite heterogeneous; the effects of genetic or environmental risk-factors were not examined.

CONCLUSIONS

Cognitive functions mediated by a fronto-parietal network, show linear impairments in unaffected relatives of BDP and schizophrenia patients; processing speed and verbal fluency impairments were evident only in schizophrenia relatives. Self-perceived symptomatology and social functioning also differ between schizophrenia and BDP relatives. The continuum seen in patients in several indices was also seen in the cognitive impairments in unaffected relatives of schizophrenia and BDP patients.

Short-Term Psychiatric Rehabilitation in Major Depressive and Bipolar Disorders: Neuropsychological-Psychosocial Outcomes

OBJECTIVE

Our pilot study aims to investigate the efficacy of a Short-Term (4 weeks) Psychiatric Rehabilitation Program (S-T PsyRP), without specific cognitive remediation trainings, on the neuropsychological performance and psychosocial functioning of inpatients with Major Depressive Disorder (MDD) or Bipolar Disorder (BD). Published studies with similar aims are lacking.

METHODS

Fifty-three inpatients with MDD and 27 with BD (type I/II) were included. The S-T PsyRP was usually performed as clinical practice at Villa San Benedetto Menni Hospital and included a variety of activities aimed at promoting personal autonomies, interpersonal/social skills, and self-care. At the beginning and the end of the hospitalization we evaluated: neuropsychological performance (cognitive tests on verbal/visual working memory, attention, visual-constructive ability, language fluency, and comprehension); psychosocial functioning by the Rehabilitation Areas Form (RAF, handbook VADO); illness severity by the Brief Psychiatric Rating Scale (BPRS). Repeated-measure ANOVA and Pearson's linear correlation were used.

RESULTS

We found significant improvement (p<0.01) in all the neuropsychological tests except for one, in 4 out of 6 RAF psychosocial areas ("involvement in ward activities", "autonomies", "self-care", and "self-management of health") and in clinical symptoms severity. No associations were found between the amelioration of clinical symptoms and neuropsychological or psychosocial improvement.

CONCLUSION

A S-T PsyRP without specific cognitive remediation trainings may improve several cognitive/functional domains in MDD or BD inpatients, probably by offering opportunities to engage in demanding problem-solving conditions and cognitively stimulating activities.

Liraglutide promotes improvements in objective measures of cognitive dysfunction in individuals with mood disorders: A pilot, open-label study

BACKGROUND

There is a paucity of treatments that are capable of reliably and robustly improving cognitive function in adults with mood disorders. Glucagon-like peptide-1 is synthesized centrally and its receptors are abundantly expressed in neural circuits subserving cognitive function. We aimed to determine the effects of liraglutide, a GLP-1 receptor (GLP-1R) agonist, on objective measures of cognition in adults with a depressive or bipolar disorder.

METHODS

In this 4-week, pilot, open-label, domain-based study (e.g. cognition), we recruited 19 individuals with major depressive disorder (MDD) or bipolar disorder (BD) and an impairment in executive function, defined as a below-average performance in the Trail Making Test-B (TMTB). Liraglutide 1.8mg/day was added as an adjunct to existing pharmacotherapy.

RESULTS

Participants had significant increases from baseline to week 4 in the TMTB standard score (age and education corrected) (Cohen's d=0.64, p=0.009) and in a composite Z-score comprising multiple cognitive tests (i.e. Digit Symbol Substitution Test, Rey Auditory Verbal Learning Test, Stroop test) (Cohen's d=0.77, p<0.001). Neither changes in mood rating scales nor metabolic parameters were associated with changes in cognitive performance (all p>0.05); however baseline insulin resistance (IR) and body mass index (BMI) moderated the changes in the composite Z-score (p=0.021 and p=0.046, respectively), indicating larger responses in individuals with higher IR and BMI at baseline. There was a significant increase in lipase (p<0.001), but individual values were above the upper limit of normality.

LIMITATIONS

Small sample size, open-label design, lack of a placebo group.

CONCLUSIONS

Liraglutide was safe and well tolerated by a sample of non-diabetic individuals with mood disorders and had beneficial effects on objective measures of cognitive function. Larger studies with controlled trial designs are necessary to confirm and expand the results described herein.

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.