Relation between functional and cognitive impairments in remitted patients with bipolar disorder and suggestions for trials targeting cognition: An exploratory study

Efficacy and safety of established and off-label ADHD drug therapies for cognitive impairment or attention-deficit hyperactivity disorder symptoms in bipolar disorder: A systematic review by the ISBD Targeting Cognition Task Force

BACKGROUND

Abnormalities in dopamine and norepinephrine signaling are implicated in cognitive impairments in bipolar disorder (BD) and attention-deficit hyperactivity disorder (ADHD). This systematic review by the ISBD Targeting Cognition Task Force therefore aimed to investigate the possible benefits on cognition and/or ADHD symptoms and safety of established and off-label ADHD therapies in BD.

METHODS

We included studies of ADHD medications in BD patients, which involved cognitive and/or safety measures. We followed the procedures of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 statement. Searches were conducted on PubMed, Embase and PsycINFO from inception until June 2023. Two authors reviewed the studies independently using the Revised Cochrane Collaboration's Risk of Bias tool for Randomized trials.

RESULTS

Seventeen studies were identified (N = 2136), investigating armodafinil (k = 4, N = 1581), methylphenidate (k = 4, N = 84), bupropion (k = 4, n = 249), clonidine (k = 1, n = 70), lisdexamphetamine (k = 1, n = 25), mixed amphetamine salts (k = 1, n = 30), or modafinil (k = 2, n = 97). Three studies investigated cognition, four ADHD symptoms, and 10 the safety. Three studies found treatment-related ADHD symptom reduction: two involved methylphenidate and one amphetamine salts. One study found a trend towards pro-cognitive effects of modafinil on some cognitive domains. No increased risk of (hypo)mania was observed. Five studies had low risk of bias, eleven a moderate risk, and one a serious risk of bias.

CONCLUSIONS

Methylphenidate or mixed amphetamine salts may improve ADHD symptoms in BD. However, there is limited evidence regarding the effectiveness on cognition. The medications produced no increased mania risk when used alongside mood stabilizers. Further robust studies are needed to assess cognition in BD patients receiving psychostimulant treatment alongside mood stabilizers.

Bipolar-ADHD comorbidity: screening for differences in neurocognition and virtual reality-based cognitive performance

OBJECTIVES

Identification of comorbid attention-deficit/hyperactivity disorder (ADHD) in patients with bipolar disorder (BD) is complicated by overlapping cognitive symptoms and methodological challenges. This cross-sectional study investigated whether virtual reality (VR)-based cognitive assessment that mimics daily life cognitive challenges can aid in the detection of sustained attention impairment in BD individuals with comorbid ADHD (BD + ADHD).

METHODS

Forty-nine fully or partially remitted outpatients with BD, of whom 14 (24%) had BD + ADHD, were assessed with the Cognition Assessment in Virtual Reality (CAVIR) test, including a sustained attention test that involves distractions, and the Screen for Cognitive Impairment in Psychiatry (SCIP). Patients were also rated for mood symptoms and functioning and completed questionnaires assessing subjective cognition and quality of life. Patients' cognitive impairment on the SCIP was estimated with reference to n = 100 demographically comparable healthy control participants.

RESULTS

BD + ADHD participants exhibited more pronounced performance deficits on the CAVIR sustained attention test (t(48) = 2.15, p = .037, d = .66). Notably, deficits on this test were proportional to self-reported daily life concentration difficulties in BD + ADHD individuals. Exploratory analyses revealed that BD + ADHD participants also displayed greater impairment on the SCIP working memory- and delayed verbal learning subtests and greater subjective cognitive complaints than BD patients without this comorbidity (p-levels < .001), but only the difference in subjective cognition survived correction for multiple comparisons (F(1,47) = 14.13, p = .005, np2 = 0.24).

CONCLUSION

Screening for deficits in sustained attention with an ecologically valid VR test involving distracting stimuli may be useful for identifying BD + ADHD individuals.

Long-term outcomes of an internet-delivered cognitive enhancement intervention targeting residual cognitive deficits after major depressive disorder: a 2-year follow-up of an open trial

Background

Cognitive deficits are common and disabling residual symptoms following major depressive disorder (MDD) and are related to increased risk of relapse. Residual cognitive deficits should thus be considered an important target for treatment. However, few have reported long-term outcomes of interventions targeting residual cognitive deficits.

Objective

This study aimed to (1) investigate change between pre-treatment and 2-year follow-up assessments in cognitive deficits, rumination, and symptoms of MDD after an internet-delivered intervention targeting residual cognitive deficits; (2) to investigate stability in outcomes between 6-month and 2-year follow-up assessments; (3) to report the number of participants' experiencing a new episode of MDD in the follow-up period; and (4) to investigate differences in outcomes between those who experienced a new episode of MDD and those who did not.

Methods

A total of 43 partly remitted adults were included to test a guided internet-delivered intervention, which consisted of 10 modules involving psychoeducation, cognitive strategies, and attention training. Participants were assessed at pre-treatment, post-treatment, after 6-months, and after 2-years, with measures assessing self-reported residual cognitive deficits, rumination, symptoms of MDD and relapse. Overall, 32 participants completed the 2-year follow-up assessment.

Results

Between the pre-treatment and 2-year follow-up assessments, there was a reduction in cognitive deficits and rumination, while there was an increase in symptoms of MDD. Cognitive deficits were stable between the 6-month and the 2-year follow-up, while there was an increase in rumination and symptoms of MDD. Thirteen of 32 participants reported a new episode of MDD during the follow-up period. The relapse group reported longer duration of MDD at pre-treatment and showed a difference in all outcomes after 2 years compared to the no-relapse group. The no-relapse group showed improvement in MDD symptoms at post-treatment, while the relapse group did not.

Conclusion

Delivering cognitive enhancement interventions over the internet is potentially related to stable improvements in residual cognitive deficits. The effects on rumination and symptoms of MDD are less certain. Lack of improvement in MDD symptoms after the intervention period should be investigated as an indicator of relapse. Results should be interpreted with caution due to the lack of control group and sample size.

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.

Functional and cognitive impairment in the first episode of depression: A systematic review

OBJECTIVES

To describe the cognitive and functional impairment in individuals with the first episode of major depressive disorder (MDD) as compared to controls and individuals with recurrent MDD. Also to describe the functional and cognitive trajectory after the first episode of MDD.

METHODS

A total of 52 studies were included in our systematic review. 32 studies compared the cognitive performance between first episode of depression (FED) and controls, 11 studies compared the cognitive performance between recurrent depression (RD) and FED, 10 compared global functioning between RD and FED, four studies assessed cognition in FED over time, and two studies assessed global functioning in FED over time.

RESULTS

The majority of studies (n = 22/32, 68.8%) found that FED subjects performed significantly worse than controls on cognitive tests, with processing speed (n = 12) and executive/working memory (n = 11) being the most commonly impaired domains. Seven out of 11 studies (63.6%) found that RD performed significantly worse than FED, with verbal learning and memory being the most commonly impaired domain (n = 4). Most studies (n = 7/10, 70%) did not find a significant difference in global functioning between RD and FED. In three of four longitudinal studies assessing cognition, subgroup analyses were used instead of directly assessing cognition in FED over time while the remaining study found significant cognitive declines over time in FED when compared to controls. The two longitudinal studies assessing functional trajectory found that functioning significantly improved over time, possibly due to the improvement of depressive symptoms.

CONCLUSION

There is strong evidence that cognitive impairment is present during the first episode of depression, and individuals with multiple episodes display greater cognitive impairment than individuals with a single episode. Future studies aimed at identifying predictors of cognitive and functional impairment after the first episode of depression are needed to describe the functional and cognitive trajectory of individuals with the first episode of MDD over time.

Cognition Assessment in Virtual Reality: Validity and feasibility of a novel virtual reality test for real-life cognitive functions in mood disorders and psychosis spectrum disorders

There is a pressing need for measures of real-life cognitive functioning in patients with mood or psychotic disorders in clinical settings and treatment trials targeting cognition. We developed the first immersive virtual reality cognition assessment tool, the Cognition Assessment in Virtual Reality (CAVIR), which assesses verbal memory, processing speed, attention, working memory and planning skills in an interactive virtual reality kitchen scenario. This study investigates the sensitivity and validity of the CAVIR for cognitive impairments in mood and psychotic disorders and its association with functioning and neuropsychological performance. Symptomatically stable patients with mood disorders (MD; n = 40) or psychosis spectrum disorders (PSD; n = 41) and healthy control participants (HC; n = 40) completed the CAVIR and standard neuropsychological tests and were rated for clinical symptoms and daily functioning. We found that the CAVIR was sensitive to cognitive impairments across MD and PSD with large effect sizes (MD: F(73) = 11.61, p < .01, ηp2 = 0.14; PSD: F(72) = 18.24, p < .001, ηp2 = 0.19). There was a moderate to strong positive correlation between performance on the CAVIR and on neuropsychological tests (r(121) = 0.58, p < .001), which prevailed after adjustment for age, years of education and verbal IQ (B = 0.67, p < .001). Lower CAVIR scores correlated moderately with more observer-rated and performance-based functional disability (r(121) = -0.30, p < .01 and r(68) = 0.44, p < .001, respectively), also after adjustment for age, years of education and verbal IQ (B = 0.03, p < .001). In conclusion, the CAVIR is a sensitive and valid instrument for measuring real-life cognitive impairments in mood and psychotic disorders. After further psychometric assessments, the CAVIR can be implemented in clinical settings and trials targeting cognition.

Exploring Clinical Correlates of Metacognition in Bipolar Disorders Using Moderation Analyses: The Role of Antipsychotics

The determinants of metacognition are still poorly understood in bipolar disorders (BD). We aimed to examine the clinical determinants of metacognition, defined as the agreement between objective and subjective cognition in individuals with BD. The participants consisted of 281 patients with BD who underwent an extensive neuropsychological battery and clinical evaluation. To assess subjective cognition, participants provided a general rating of their estimated cognitive difficulties. Clinical characteristics of BD were also recorded, along with medication. We studied the potential moderation of the association between cognitive complaints and global objective cognitive performance by several clinical variables with ordinal logistic regressions. Depression and impulsivity were associated with greater cognitive complaints. The only variable that moderated the relationship between objective and subjective cognition in the global model was the prescription of antipsychotics. Patients taking antipsychotics had a poorer association between cognitive complaints and objective neuropsychological performance. This result suggests a role for dopamine in the modulation of metacognitive performance, and calls for the systematic control of antipsychotic medication in future studies documenting metacognitive deficits in severe and persistent mental disorders. Depression and impulsivity should be investigated as potential therapeutic targets for individuals with BD and cognitive complaints, before proposing an extensive neuropsychological evaluation.

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.

Neurocognitive impairment and evidence-based treatment options in Bipolar disorder

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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