The effects of cognitive remediation on cognitive abilities and real-world functioning among people with bipolar disorder: A systematic review: Special Section on "Translational and Neuroscience Studies in Affective Disorders". Section Editor, Maria Nobile MD, PhD. This Section of JAD focuses on the relevance of translational and neuroscience studies in providing a better understanding of the neural basis of affective disorders. The main aim is to briefly summaries relevant research findings in clinical neuroscience with particular regards to specific innovative topics in mood and anxiety disorders

Cognitive rehabilitation in bipolar spectrum disorder: A systematic review

Background and objectives

Neurocognitive deficits in bipolar disorder (BD) have a negative impact on the quality of life, even during the euthymic phase. And many studies conducted to improve cognitive deficits in bipolar disorder. This systematic review aims to summarize studies on cognitive rehabilitation (CR) conducted in bipolar patients and evaluate its impact on neurocognitive deficits. The primary objective is to explore how CR interventions can enhance cognitive functioning, treatment outcomes, and overall quality of life in this population.

Methods

A comprehensive search was conducted on PubMed, Google Scholar, Scopus, Embase, and PsycINFO databases from 1950 to 2023, following the 2015 PRISMA-P guidelines, using search terms related to BD and CR.

Results

The initial search yielded 371 titles across the five databases. After applying inclusion and exclusion criteria through screening, a total of 23 articles were included in the study. The selected articles evaluated verbal memory, attention, executive functions, and social cognition.

Conclusion

The findings suggest that CR can be an effective treatment approach for bipolar patients, aimed at enhancing their cognitive abilities, treatment outcomes, and overall quality of life. The primary finding of this study indicates that cognitive-behavioral therapy (CBT) protocols, skill training, and homework exercises, which offer a daily structure, social support, and opportunities for exchanging coping strategies, are more effective in enhancing cognitive functions. However, it is important to acknowledge the notable limitations of this review. Firstly, we did not assess the methodological rigor of the included studies. Additionally, there was a lack of detailed analysis regarding specific cognitive rehabilitation approaches that adhere to core CR principles, resulting in increased heterogeneity within the reviewed studies.

Study protocol - elucidating the neural correlates of functional remediation for older adults with bipolar disorder

Introduction

Beyond mood abnormalities, bipolar disorder (BD) includes cognitive impairments that worsen psychosocial functioning and quality of life. These deficits are especially severe in older adults with BD (OABD), a condition expected to represent most individuals with BD in the upcoming years. Restoring the psychosocial functioning of this population will thus soon represent a public health priority. To help tackle the problem, the Bipolar and Depressive Disorders Unit at the Hospital Clínic of Barcelona has recently adapted its Functional Remediation (FR) program to that population, calling it FROA-BD. However, while scarce previous studies localize the neural mechanisms of cognitive remediation interventions in the dorsal prefrontal cortex, the specific mechanisms are seldom unknown. In the present project, we will investigate the neural correlates of FR-OABD to understand its mechanisms better and inform for potential optimization. The aim is to investigate the brain features and changes associated with FROA-BD efficacy.

Methods

Thirty-two individuals with OABD in full or partial remission will undergo a magnetic resonance imaging (MRI) session before receiving FR-OABD. After completing the FR-OABD intervention, they will undergo another MRI session. The MRI sessions will include structural, diffusion-weighted imaging (DWI), functional MRI (fMRI) with working memory (n-back) and verbal learning tasks, and frontal spectroscopy. We will correlate the pre-post change in dorsolateral and dorsomedial prefrontal cortices activation during the n-back task with the change in psychosocial functioning [measured with the Functioning Assessment Short Test (FAST)]. We will also conduct exploratory whole-brain correlation analyses between baseline or pre-post changes in MRI data and other clinical and cognitive outcomes to provide more insights into the mechanisms and explore potential brain markers that may predict a better treatment response. We will also conduct separate analyses by sex.

Discussion

The results of this study may provide insights into how FROA-BD and other cognitive remediations modulate brain function and thus could optimize these interventions.

Efficacy of cognitive remediation in bipolar disorder: systematic review and meta-analysis of randomized controlled trials

A significant percentage of people with bipolar disorder (BD) exhibit suboptimal functional adjustment, even when appropriately treated and after symptomatic recovery is achieved. Given that cognitive impairment is one of the strongest correlates of socio-occupational outcomes and quality of life in BD, cognitive remediation (CR) is currently acknowledged as a promising treatment that could help bridge the gap between symptomatic and full functional recovery. The aim of this review was to explore the efficacy of CR approaches in improving cognitive and functional outcomes in BD patients. PubMed, PsycINFO, and CENTRAL were searched from inception to November 2022. Randomized controlled trials exploring the effects of CR on cognition and/or functional adjustment in adult BD patients were eligible. Ten studies based on seven independent trials (n = 586) were included. Change-score effect sizes (Hedges' g) were obtained for efficacy outcome measures and combined by means of meta-analytic procedures. Small but significant overall effects were observed for working memory (g = 0.32, 95% CI 0.11-0.52), planning (g = 0.30, 95% CI 0.03-0.56), and verbal learning (g = 0.40, 95% CI 0.15-0.66). However, CR was not found to exert any significant effects on functional outcomes at treatment completion or at follow-up assessment. Although CR may modestly enhance the cognitive performance of BD patients, this effect does not translate into an improvement at the functional level. The current data do not support the inclusion of CR as a treatment recommendation in clinical practice guidelines for the management of BD.

Prefrontal, parietal, and limbic condition-dependent differences in bipolar disorder: a large-scale meta-analysis of functional neuroimaging studies

BACKGROUND

Over the past few decades, neuroimaging research in Bipolar Disorder (BD) has identified neural differences underlying cognitive and emotional processing. However, substantial clinical and methodological heterogeneity present across neuroimaging experiments potentially hinders the identification of consistent neural biomarkers of BD. This meta-analysis aims to comprehensively reassess brain activation and connectivity in BD in order to identify replicable differences that converge across and within resting-state, cognitive, and emotional neuroimaging experiments.

METHODS

Neuroimaging experiments (using fMRI, PET, or arterial spin labeling) reporting whole-brain results in adults with BD and controls published from December 1999-June 18, 2019 were identified via PubMed search. Coordinates showing significant activation and/or connectivity differences between BD participants and controls during resting-state, emotional, or cognitive tasks were extracted. Four parallel, independent meta-analyses were calculated using the revised activation likelihood estimation algorithm: all experiment types, all resting-state experiments, all cognitive experiments, and all emotional experiments. To confirm reliability of identified clusters, two different meta-analytic significance tests were employed.

RESULTS

205 published studies yielding 506 individual neuroimaging experiments (150 resting-state, 134 cognitive, 222 emotional) comprising 5745 BD and 8023 control participants were included. Five regions survived both significance tests. Individuals with BD showed functional differences in the right posterior cingulate cortex during resting-state experiments, the left amygdala during emotional experiments, including those using a mixed (positive/negative) valence manipulation, and the left superior and right inferior parietal lobules during cognitive experiments, while hyperactivating the left medial orbitofrontal cortex during cognitive experiments. Across all experiments, there was convergence in the right caudate extending to the ventral striatum, surviving only one significance test.

CONCLUSIONS

Our findings indicate reproducible localization of prefrontal, parietal, and limbic differences distinguishing BD from control participants that are condition-dependent, despite heterogeneity, and point towards a framework for identifying reproducible differences in BD that may guide diagnosis and treatment.

A Recovery-Oriented Program for People with Bipolar Disorder through Virtual Reality-Based Cognitive Remediation: Results of a Feasibility Randomized Clinical Trial

Background: Cognitive impairment is a frequent consequence of bipolar disorder (BD) that is difficult to prevent and treat. In addition, the quality of the preliminary evidence on the treatment of BD through Cognitive Remediation (CR) with traditional methods is poor. This study aims to evaluate the feasibility of a CR intervention with fully immersive Virtual Reality (VR) as an additional treatment for BD and offers preliminary data on its efficacy. Methods: Feasibility randomized controlled cross-over clinical study, with experimental condition lasting three months, crossed between two groups. Experimental condition: CR fully immersive VR recovery-oriented program plus conventional care; Control condition: conventional care. The control group began the experimental condition after a three months period of conventional care (waiting list). After the randomization of 50 people with BD diagnosis, the final sample consists of 39 participants in the experimental condition and 25 in the control condition because of dropouts. Results: Acceptability and tolerability of the intervention were good. Compared to the waitlist group, the experimental group reported a significant improvement regarding cognitive functions (memory: p = 0.003; attention: p = 0.002, verbal fluency: p = 0.010, executive function: p = 0.003), depressive symptoms (p = 0.030), emotional awareness (p = 0.007) and biological rhythms (p = 0.029). Conclusions: The results are preliminary and cannot be considered exhaustive due to the small sample size. However, the evidence of efficacy, together with the good acceptability of the intervention, is of interest. These results suggest the need to conduct studies with larger samples that can confirm this data. Trial registration: ClinicalTrialsgov NCT05070065, registered in September 2021

A meta-analytic investigation of cognitive remediation for mood disorders: Efficacy and the role of study quality, sample and treatment factors

BACKGROUND

The number of randomized, controlled studies of cognitive remediation (CR) for mood disorders (major depressive disorder [MDD] and bipolar illness [BD]), has grown substantially over the past 10 years. The role of study quality, participant characteristics, and intervention features in CR treatment effects remains largely unknown.

METHODS

Electronic databases were searched up to February 2022 using variants of the key words: "cognitive remediation", "clinical trials", "major depressive disorder" and "bipolar disorder". This search produced 22 unique randomized, controlled trials that met all inclusion criteria for the study. Data were extracted by 3 authors with strong reliability (>90 %). Primary cognitive, and secondary symptom and functional outcomes were assessed with random effects models.

RESULTS

The meta-analysis (993 participants) revealed that CR produced significant small-to-moderate size effects in attention, verbal learning and memory, working memory and executive function (Hedge's g = 0.29-0.45). CR produced a small-moderate effect on one secondary outcome: depressive symptoms (g = 0.33). CR programs that used an individualized approach produced larger effects on executive function. Samples with lower baseline IQ were more likely to benefit from CR on measures of working memory. Sample age, education, gender, or baseline depressive symptomatology did not serve as barriers to treatment gains, and observed effects were not epiphenomena of poorer design quality.

LIMITATIONS

The number of RCTs remains low.

CONCLUSIONS

CR produces small to moderate improvements in cognition and depressive symptoms in mood disorders. Future research should study how CR might be optimized to help generalize CR-related cognitive and symptom improvements to function.

Does cognitive improvement translate into functional changes? Exploring the transfer mechanisms of cognitive remediation therapy for euthymic people with bipolar disorder

BACKGROUND

Bipolar disorder (BD) is associated with cognitive and functional difficulties, persistent beyond mood episodes. Cognitive remediation (CR) is a psychological therapy targeting cognitive and functioning difficulties. Recent evidence suggests that CR may enhance long-term functioning but transfer mechanisms on functional outcomes have not been explored. We aim to investigate whether and how cognitive gains after CR transfer to functional improvement.

METHODS

We considered data from a randomized controlled trial comparing CR (n = 40) to treatment-as-usual (TAU; n = 40) in euthymic people with BD. Treatment outcomes included individual cognitive domains and global cognition, psychosocial functioning, and goal attainment. Regression-based mediation and moderation modelling were used to assess whether and how post-treatment cognitive changes translate into functional improvement at follow-up, three months after treatment end.

RESULTS

Cognitive gains after CR transferred to functional changes three months later: improvement in post-treatment global cognition partially mediated the effect of CR on psychosocial functioning (standardized indirect effect: -0.23, 95% CI -0.51 to -0.04). Goal attainment was not significantly mediated by changes in cognition, but post-treatment cognitive performance moderated the effect of CR on the GAS at follow-up (interaction effect: 0.78, 95% CI 0.08-1.55).

CONCLUSIONS

Our findings suggest that cognitive improvements contribute to functional improvement but transfer mechanisms differ between psychosocial functioning and idiosyncratic recovery goals. Cognition accounted for only a proportion of the total CR effect on functional outcomes. Future studies should consider other variables, such as metacognition, that may drive the transfer of CR effects to functional outcomes.

Fully Immersive Virtual Reality-Based Cognitive Remediation for Adults with Psychosocial Disabilities: A Systematic Scoping Review of Methods Intervention Gaps and Meta-Analysis of Published Effectiveness Studies

BACKGROUND

Cognitive Remediation (CR) programs are effective for the treatment of mental diseases; in recent years, Virtual Reality (VR) rehabilitation tools are increasingly used. This study aimed to systematically review and meta-analyze the published randomized controlled trials that used fully immersive VR tools for CR programs in psychiatric rehabilitation. We also wanted to map currently published CR/VR interventions, their methods components, and their evidence base, including the framework of the development intervention of CR in fully immersive VR.

METHODS

Level 1 of evidence. This study followed the PRISMA extension for Scoping Reviews and Systematic Review. Three electronic databases (Pubmed, Cochrane Library, Embase) were systematically searched, and studies were included if they met the eligibility criteria: only randomized clinical trials, only studies with fully immersive VR, and only CR for the adult population with mental disorders.

RESULTS

We found 4905 (database) plus 7 (manual/citation searching articles) eligible studies. According to inclusion criteria, 11 studies were finally reviewed. Of these, nine included patients with mild cognitive impairment, one with schizophrenia, and one with mild dementia. Most studies used an ecological scenario, with improvement across all cognitive domains. Although eight studies showed significant efficacy of CR/VR, the interventions' development was poorly described, and few details were given on the interventions' components.

CONCLUSIONS

Although CR/VR seems to be effective in clinical and feasibility outcomes, the interventions and their components are not clearly described. This limits the understanding of the effectiveness and undermines their real-world implementation and the establishment of a gold standard for fully immersive VR/CR.

Technology and Mental Health: State of the Art for Assessment and Treatment

Technology is ubiquitous in society and is now being extensively used in mental health applications. Both assessment and treatment strategies are being developed and deployed at a rapid pace. The authors review the current domains of technology utilization, describe standards for quality evaluation, and forecast future developments. This review examines technology-based assessments of cognition, emotion, functional capacity and everyday functioning, virtual reality approaches to assessment and treatment, ecological momentary assessment, passive measurement strategies including geolocation, movement, and physiological parameters, and technology-based cognitive and functional skills training. There are many technology-based approaches that are evidence based and are supported through the results of systematic reviews and meta-analyses. Other strategies are less well supported by high-quality evidence at present, but there are evaluation standards that are well articulated at this time. There are some clear challenges in selection of applications for specific conditions, but in several areas, including cognitive training, randomized clinical trials are available to support these interventions. Some of these technology-based interventions have been approved by the U.S. Food and Drug administration, which has clear standards for which types of applications, and which claims about them, need to be reviewed by the agency and which are exempt.

Cognitive Remediation Virtual Reality Tool a Recovery-Oriented Project for People with Bipolar Disorder: Protocol of a Feasibility Randomized Clinical Trial

Introduction

Cognitive deficits are considered a fundamental component of bipolar disorder due to the fact that they negatively impact personal/social functioning. Cognitive remediation interventions are effective in the treatment of various psychosocial disorders, including bipolar disorder. The use of Virtual reality as a rehabilitation tool has produced scientific evidence in recent years, especially in cardiovascular, neurological, and musculoskeletal rehabilitation. This study aims at evaluating the feasibility of a Cognitive Remediation Virtual Reality Program (CEREBRUM) for people with bipolar disorder in psychiatric rehabilitation.

Material and Methods

Feasibility randomized controlled cross-over clinical study; we randomized 50 people from the Consultation and Psychosomatic Psychiatry Center of the University Hospital of Cagliari (San Giovanni di Dio Civil Hospital) with a diagnosis of bipolar disorder. We propose a cognitive remediation program in virtual reality (CEREBRUM), 3 months with 2 weekly sessions, for the experimental group and a usual care program for the control group (psychiatric visit and/or psychotherapy).

Results

The results of the trial will be published in international peer-reviewed journals and will be disseminated at international meetings and congress.

Discussion

This RCT aims, with regards to its feasibility and design, to provide information about a confirmatory trial that evaluates the effectiveness of a Virtual Reality Cognitive Remediation program in psychiatric rehabilitation for the treatment of cognitive dysfunction in people with bipolar disorder.

Conclusion

The results that we analyzed at the end of the RCT will have an impact on psychiatric rehabilitation research with a focus on improving the application of technologies for mental health.Trial registration: ClinicalTrialsgov NCT05070065, registered on September 2021.

Real-World Functioning in Psychiatric Outpatients: Predictive Factors

Introduction: Investigations on predictors of real-world functioning were mainly performed in patients with schizophrenia, while fewer studies have been conducted in other psychiatric disorders. Objective: Our objective was to identify clinical, socio-demographic, and illness-related predictors of real-world functioning during 12 months of standard treatments in outpatients with different diagnoses. Methods: Outpatients (n = 1019) with schizophrenia (SZ), major depressive disorder (MDD), bipolar disorder (BD), and borderline personality disorder (BPD) were evaluated with the following tools: SCID-5-CV and SCID-5-PD, CGI-S, SAT-P, DAI-10, and PSP. Change of PSP (ΔPSP) between baseline and 12 months was used as the dependent variable in multiple regression analysis. Results: Higher PSP score at baseline and the achievement of main milestones predicted better functioning after follow-up in all subgroups of patients, with the exception of BD. In the total sample, ΔPSP was related to age of onset, treatments, and quality of life, and inversely related to psychiatric anamnesis, antidepressants, and global symptoms. In SZ, ΔPSP was related to adherence and quality of life. In MDD, ΔPSP was related to psychotherapy and quality of life, and inversely related to antidepressants and global symptoms. In BD, ΔPSP was related to age of onset, antipsychotics, and quality of life, while it was inversely related to psychiatric anamnesis. In BPD, antipsychotics, mood stabilizers, psychotherapy, and quality of life were directly related to ΔPSP, while suicidal attempts and global symptoms had an inverse relation. Conclusions: Several socio-demographic and illness-related variables predicted improvement of real-world functioning, besides psychopathology and severity of the disease.

Neural network of bipolar disorder: Toward integration of neuroimaging and neurocircuit-based treatment strategies

Bipolar disorder (BD) is a complex psychiatric disorder characterized by dysfunctions in three domains including emotional processing, cognitive processing, and psychomotor dimensions. However, the neural underpinnings underlying these clinical profiles are not well understood. Based on the reported data, we hypothesized that (i) the core neuropathology in BD is damage in fronto-limbic network, which is associated with emotional dysfunction; (ii) changes in intrinsic brain network, such as sensorimotor network, salience network, default-mode network, central executive network are associated with impaired cognition function; and (iii) beyond the dopaminergic-driven basal ganglia-thalamo-cortical motor circuit modulated by other neurotransmitter systems, such as serotonin (subcortical-cortical modulation), the sensorimotor network and related motor function modulated by other non-motor networks such as the default-mode network are involved in psychomotor function. In this review, we propose a neurocircuit-based clinical characteristics and taxonomy to guide the treatment of BD. We draw on findings from neuropsychological and neuroimaging studies in BD and link variations in these clinical profiles to underlying neurocircuit dysfunctions. We consider pharmacological, psychotherapy, and neuromodulatory treatments that could target those specific neurocircuit dysfunctions in BD. Finally, it is suggested that the methods of testing the neurocircuit-based taxonomy and important limitations to this approach should be considered in future.

Cognitive flexibility, central coherence, and quality of life in anorexia nervosa

BACKGROUND

Anorexia nervosa (AN) has consistently been found to be associated with poor cognitive flexibility and central coherence. These two cognitive functions have been considered important maintenance factors in AN and are addressed by specific treatment approaches such as cognitive remediation therapy. While there is clear empirical evidence that difficulties in such cognitive functions are related to impaired daily functioning in schizophrenia and bipolar disorder, this potential association has received only little attention in AN research so far. Therefore, the aim of this study was to examine potential relationships between weak cognitive flexibility, central coherence, and poor quality of life (QoL) in AN.

METHODS

Cognitive flexibility and central coherence were measured by both neuropsychological (i.e., performance based) and self-report measures alongside with self-reported QoL in a sample of 138 adult patients with AN.

RESULTS

Self-report but not performance based measures of cognitive flexibility and central coherence were associated with QoL. Weaker cognitive flexibility and central coherence were correlated with poorer QoL. These associations were independent of comorbid depression. The link between weak central coherence and poor QoL was particularly strong in patients with the restricting subtype of AN. The link between cognitive flexibility and QoL, however, was independent of AN subtype.

CONCLUSIONS

Weak cognitive flexibility and central coherence are associated with low QoL in AN, especially in patients with the restrictive subtype. However, this relationship is dependent on the method of measurement, where self-report measures seem to be more relevant than performance based measures.

Effect of Action-Based Cognitive Remediation on cognitive impairment in patients with remitted bipolar disorder: A randomized controlled trial

OBJECTIVES

Cognitive impairment affects many patients with bipolar disorder (BD), and treatments with replicated pro-cognitive effects are lacking. This study aimed to assess the effect of Action-Based Cognitive Remediation (ABCR) vs control treatment on cognitive impairment in patients with BD.

METHODS

Patients with remitted BD with objective cognitive impairment were randomized to 10 weeks of ABCR vs control treatment, and assessed at baseline, after 2 weeks of treatment, at treatment completion and at 6 months follow-up. The primary outcome was a cognitive composite score. Secondary outcomes were executive function and observer-rated functional capacity. Tertiary measures included additional neuropsychological tests, performance-based functional capacity and quality of life. Data were analysed with linear mixed effects models.

RESULTS

In total, 64 participants were randomized; given three dropouts before the baseline assessments, data were analysed for 61 participants (ABCR: n = 32, control: n = 29). There was no effect on ABCR vs control on the primary cognitive composite score (P-values ≥.60). At treatment completion, there was a large effect of ABCR vs control on the secondary executive function measure (treatment effect= -0.16, 95% CI [-0.27, -0.05], P ≤ .01, d = 0.65), and on subjective cognitive functioning (treatment effect = -5.38, 95% CI [-8.13, -2.67], P ≤ .001, d = 0.80), which disappeared at follow-up. There was no treatment-effect on functioning, and no association between cognitive and functional change.

CONCLUSIONS

There was no effect of ABCR on the cognitive composite score. However, there was an effect on executive function and subjective cognitive functioning suggesting that ABCR may be relevant for patients with executive dysfunction.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03295305.

Cognitive remediation therapy for patients with bipolar disorder: A randomised proof-of-concept trial

OBJECTIVES

Cognitive remediation therapy (CRT) may benefit people with bipolar disorder type I and II for whom cognitive impairment is a major contributor to disability. Extensive research has demonstrated CRT to improve cognition and psychosocial functioning in people with different diagnoses, but randomised trials of evidenced therapy programmes are lacking for bipolar disorders. The Cognitive Remediation in Bipolar (CRiB) study aimed to determine whether an established CRT programme is feasible and acceptable for people with bipolar disorders.

METHODS

This proof-of-concept, single-blind randomised trial recruited participants aged 18-65 with bipolar disorder, not currently experiencing an episode. They were 1:1 block randomised to treatment-as-usual (TAU) with or without individual CRT for 12 weeks. The partly computerised CRT programme ("CIRCuiTS") was therapist-led and is evidence-based from trials in those with psychotic illnesses. Data were collected and analysed by investigators blinded to group allocation. The main outcomes (week 13 and 25) examined participant retention, intervention feasibility and putative effects of CRT on cognitive and psychosocial functioning via intention-to-treat analyses.

TRIAL REGISTRATION

ISRCTN ID32290525.

RESULTS

Sixty participants were recruited (02/2016-06/2018) and randomised to CRT (n = 29) or TAU (n = 31). Trial withdrawals were equivalent (CRT n = 2/29; TAU n = 5/31). CRT satisfaction indicated high acceptability. Intention-to-treat analyses (N = 60) demonstrated greater improvements for CRT- than TAU-randomised participants: at both week 13 and 25, CIRCuiTS participants showed larger improvements in the following domains (week 25 effect sizes reported here): IQ (SES = 0.71, 95% CI [0.29,1.13]), working memory (SES = 0.70, 95% CI [0.31,1.10]), executive function (SES = 0.93, 95% CI [0.33,1.54]), psychosocial functioning (SES = 0.49, 95% CI [0.18,0.80]) and goal attainment (SES = 2.02, 95% CI [0.89,3.14]). No serious adverse events were reported.

CONCLUSIONS

CRT is feasible for individuals with bipolar disorders and may enhance cognition and functioning. The reported effect sizes from this proof-of-concept trial encourage further investigation in a definitive trial.

Clinical Features, Neuropsychology and Neuroimaging in Bipolar and Borderline Personality Disorder: A Systematic Review of Cross-Diagnostic Studies

Background: Bipolar Disorder (BD) and Borderline Personality Disorder (BPD) have clinically been evolving as separate disorders, though there is still debate on the nosological valence of both conditions, their interaction in terms of co-morbidity or disorder spectrum and their distinct pathophysiology. Objective: The objective of this review is to summarize evidence regarding clinical features, neuropsychological performance and neuroimaging findings from cross-diagnostic studies comparing BD and BPD, to further caracterize their complex interplay. Methods: Using PubMed, PsycINFO and TripDataBase, we conducted a systematic literature search based on PRISMA guidelines of studies published from January 1980 to September 2019 which directly compared BD and BPD. Results: A total of 28 studies comparing BD and BPD were included: 19 compared clinical features, 6 neuropsychological performance and three neuroimaging abnormalities. Depressive symptoms have an earlier onset in BPD than BD. BD patients present more mixed or manic symptoms, with BD-I differing from BPD in manic phases. BPD patients show more negative attitudes toward others and self, more conflictive interpersonal relationships, and more maladaptive regulation strategies in affective instability with separate pathways. Impulsivity seems more a trait in BPD rather than a state as in BD. Otherwise, BD and BPD overlap in depressive and anxious symptoms, dysphoria, various abnormal temperamental traits, suicidal ideation, and childhood trauma. Both disorders differ and share deficits in neuropsychological and neuroimaging findings. Conclusion: Clinical data provide evidence of overlapping features in both disorders, with most of those shared symptoms being more persistent and intense in BPD. Thus, categorical classifications should be compared to dimensional approaches in transdiagnostic studies investigating BPD features in BD regarding their respective explanatory power for individual trajectories. Systematic Review Registration: The search strategy was pre-registered in PROSPERO: CRD42018100268.

Minimum clinically important differences for the Functioning Assessment Short Test and a battery of neuropsychological tests in bipolar disorders: results from the FACE-BD cohort

AIMS

Establishing the minimum clinically important difference (MCID) in functioning and cognition is essential to the interpretation of the research and clinical work conducted in bipolar disorders (BD). The present study aimed to estimate the MCID for the Functioning Assessment Short Test (FAST) and a battery of neuropsychological tests in BD.

METHODS

Anchor-based and distributive methods were used to estimate the MCID for the FAST and cognition using data from a large, multicentre, observational cohort of individuals with BD. The FAST and cognition were linked with the Clinical Global Impressions Scale-Severity (CGI-S) and Global Assessment of Functioning (GAF) using an equipercentile method. The magnitude of the standard error measurement (s.e.m.) provided another estimate of the MCID.

RESULTS

In total, 570 participants were followed for 2 years. Cross-sectional CGI-S and GAF scores were linked to a threshold ⩽7 on the FAST for functional remission. The MCID for the FAST equalled 8- or 9-points change from baseline using the CGI-S and GAF. One s.e.m. on the FAST corresponded to 7.6-points change from baseline. Cognitive variables insufficiently correlated with anchor variables (all ρ <0.3). One s.e.m. for cognitive variables corresponded to a range of 0.45 to 0.93-s.d. change from baseline.

CONCLUSIONS

These findings support the value of the estimated MCID for the FAST and cognition and may be a useful tool to evaluate cognitive and functional remediation effects and improve patient functional outcomes in BD. The CGI-S and GAF were inappropriate anchors for cognition. Further studies may use performance-based measures of functioning instead.