Neuropsychological performance in bipolar I, bipolar II and unipolar depression patients: a longitudinal, naturalistic study

Differences in cognitive impairment and its correlation with circulating cell-free mitochondrial DNA in medication-free depression and bipolar depression patients

OBJECTIVE

This study aimed to investigate whether there are differences in cognitive impairment between medication-free patients with bipolar depression (BD) and major depressive disorder (MDD) and whether these differences are related to circulating cell-free mtDNA (ccf-mtDNA).

METHODS

For this cross-sectional study, 76 outpatients with BD, 86 outpatients with MDD and 70 healthy controls (HCs) were enrolled. Sociodemographic and clinical data were collected. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Stroop Color-Word Test were used to assess cognitive function. Plasma ccf-mtDNA levels were measured via qPCR.

RESULTS

BD and MDD patients had similar scores for immediate memory, language, attention, delayed memory, the RBANS total score, Stroop color, Stroop word, and Stroop total score, which were significantly lower than the HCs. The visuospatial/constructive scores of the BD patients were significantly lower than those of the HCs (p < 0.001) and MDD patients (p = 0.008), but there was no difference between the HCs and MDD patients. The ccf-mtDNA levels in the BD and MDD patient groups were significantly higher than those in the HC group, and those in the MDD group were higher than those in the BD group (p = 0.016). Multiple stepwise regression analysis showed that ccf-mtDNA was negatively correlated with language in patients with depression (t = -2.11, p = 0.039).

CONCLUSION

There were differences in specific cognitive dimensions between patients with BD and MDD. Increased ccf-mtDNA levels were found in BD and MDD patients, suggesting ccf-mtDNA may be involved in the pathophysiology of MDD and BD.

Shared and distinct patterns of default mode network dysfunction in major depressive disorder and bipolar disorder: A comparative meta-analysis

BACKGROUND

While patients with major depressive disorder (MDD) and bipolar disorder (BD) exhibited default mode network (DMN) dysfunction revealed by aberrant resting-state functional connectivity (rsFC) patterns, previous findings have been inconsistent. Little is known about the similarities and differences in DMN rsFC between MDD and BD.

METHODS

A voxel-wise meta-analysis of seed-based DMN rsFC studies on MDD or BD was performed using the Seed-based d Mapping software with permutation of subject images (SDM-PSI). Aberrant DMN rsFC in both disorders was investigated separately, followed by conjunction and between-disorder comparison analyses. Functional decoding was performed to implicate the psychophysiological underpinnings of derived brain abnormalities.

RESULTS

Thirty-four studies comparing 1316 MDD patients with 1327 HC, and 22 studies comparing 1059 BD patients with 1396 HC were included. Compared to HC, MDD patients exhibited DMN hyperconnectivity with frontolimbic systems, and hypoconnectivity with temporal lobe and posterior cingulate cortex. BD patients displayed increased DMN connectivity with bilateral precuneus, and reduced connectivity with prefrontal cortex and middle temporal gyrus. No common patterns of DMN rsFC abnormalities were observed between MDD and BD. Compared to BD, MDD patients showed DMN hyperconnectivity with triangular part of the left inferior frontal gyrus and left fusiform gyrus. Functional decoding found that patterns of DMN rsFC alteration between MDD and BD were primarily related to action and perception domains.

CONCLUSION

Distinct DMN dysfunction patterns in MDD and BD enhance current understanding of the neural substrates of mood disorders and may provide a potential biomarker for differentiation.

Neuropsychological performance in women at risk of postpartum depression and postpartum psychosis

PURPOSE

While neuropsychological deficits are commonly observed in affective and psychotic disorders, this remains unexplored in these disorders when they occur during pregnancy and the postpartum period.

METHODS

A neuropsychological test battery was administered to women defined at risk of postpartum depression (PD, N = 53) because having either a current or past diagnosis of major depressive disorder, women at risk of postpartum psychosis (PP, N = 43) because of a diagnosis of bipolar disorder or schizoaffective disorder and/or a previous episode of PP and women not at risk (NR, N = 48) in the third trimester of pregnancy. Generalized and specific cognitive abilities were compared between groups.

RESULTS

Women at risk of PP presented worse executive functions and processing speed compared to NR and worse performance compared to women at risk of PD across all cognitive domains. In addition, women at risk of PP who developed a psychiatric relapse in the first four weeks post-partum showed worse verbal learning and memory, visual memory, executive functions and processing speed in pregnancy compared to NR, whereas women at risk of PP who remained well presented neuropsychological performance that was intermediate between that of the women NR and those at risk of PP who developed symptoms. There were no differences in performance between women at risk of PD and the NR women, even if 31 women at risk of PD presented depressive symptoms at the time of cognitive assessment.

CONCLUSIONS

Our findings in women at risk of PP align with neuropsychological findings in individuals with, or at risk of psychosis unrelated to pregnancy. In addition, initial evidence that women at risk of PP who develop a psychiatric relapse in the postpartum show a particularly poor neuropsychological performance in pregnancy suggests that this could be considered part of a phenotype for the disease and help guiding future preventive strategies in this clinical population. In women at risk of PD, the presence of depressive symptoms did not influence cognitive performance.

Cognition and gut microbiota in schizophrenia spectrum and mood disorders: A systematic review

FRILEUX, M., BOLTRI M. and al. Cognition and Gut microbiota in schizophrenia spectrum and mood disorders: a Systematic Review. NEUROSCI BIOBEHAV REV (1) 2024 Schizophrenia spectrum disorders and major mood disorders are associated with cognitive impairments. Recent studies suggest a link between gut microbiota composition and cognitive functioning. Here, we review the relationship between gut microbiota and cognition in these disorders. To do this, we conducted a systematic review, searching Cochrane Central Register of Controlled Trials, EBSCOhost, Embase, Pubmed, Scopus, and Web of Science. Studies were included if they investigated the relationship between gut microbiota composition and cognitive function through neuropsychological assessments in patients with bipolar, depressive, schizophrenia spectrum, and other psychotic disorders. Ten studies were identified. Findings underscore a link between gut dysbiosis and cognitive impairment. This relationship identified specific taxa (Haemophilus, Bacteroides, and Alistipes) as potential contributors to bolstered cognitive performance. Conversely, Candida albicans, Toxoplasma gondii, Streptococcus and Deinococcus were associated with diminished performance on cognitive assessments. Prebiotics and probiotics interventions were associated with cognitive enhancements, particularly executive functions. These results emphasize the role of gut microbiota in cognition, prompting further exploration of the underlying mechanisms paving the way toward precision psychiatry.

Neurocognitive Changes in Patients with Post-COVID Depression

Background: Depression and cognitive impairment are recognized complications of COVID-19. This study aimed to assess cognitive performance in clinically diagnosed post-COVID depression (PCD, n = 25) patients using neuropsychological testing. Methods: The study involved 71 post-COVID patients with matched control groups: recovered COVID-19 individuals without complications (n = 18) and individuals without prior COVID-19 history (n = 19). A post-COVID depression group (PCD, n = 25) was identified based on psychiatric diagnosis, and a comparison group (noPCD, n = 46) included participants with neurological COVID-19 complications, excluding clinical depression. Results: The PCD patients showed gender-dependent significant cognitive impairment in the MoCA, Word Memory Test (WMT), Stroop task (SCWT), and Trail Making Test (TMT) compared to the controls and noPCD patients. Men with PCD showed worse performances on the SCWT, in MoCA attention score, and on the WMT (immediate and delayed word recall), while women with PCD showed a decline in MoCA total score, an increased processing time with less errors on the TMT, and worse immediate recall. No differences between groups in Sniffin's stick test were found. Conclusions: COVID-related direct (post-COVID symptoms) and depression-mediated (depression itself, male sex, and severity of COVID-19) predictors of decline in memory and information processing speed were identified. Our findings may help to personalize the treatment of depression, taking a patient's gender and severity of previous COVID-19 disease into account.

Processing speed and sustained attention in bipolar disorder and major depressive disorder: A systematic review and meta-analysis

OBJECTIVES

Cognitive impairment is a core feature of bipolar disorder (BD) and major depressive disorder (MDD). Deficits in processing speed (PS) and sustained attention (SA) may be particularly impaired and may underpin a broader profile of deficits, however current knowledge of the nature of these impairments is limited by heterogeneous results in the literature. Few reviews to date have attempted to disentangle sources of heterogeneity to assess the presence and magnitude of impairments in PS and SA in BD and MDD.

METHODS

One hundred and three studies were reviewed to examine performance in tests of PS and SA in BD (n = 3452) and MDD (n = 5461) compared to healthy controls (n = 8016). Neuropsychological methodology used in the literature was summarised. Data were meta-analysed to assess impairments in PS and SA for each neuropsychological test separately. Subgroup analysis was performed across mood states to investigate sources of heterogeneity.

RESULTS

Impairments were found across most neuropsychological tests, with small to large effect sizes for BD (range: d = 0.19-0.96) and MDD (range: d = 0.29-0.86). Impairments were present in symptomatic states and euthymia in most cases. Some outcome measures were not impaired in euthymia. Heterogeneity was observed for most neuropsychological tests and remained after separating by mood state. There inadequate data to meta-analyse some outcome measures, particularly for symptomatic groups.

CONCLUSION

Impairments in PS and SA in BD and MDD can be observed across most neuropsychological tests. Future research should further investigate the nature of these impairments across mood states, controlling for clinical confounds.

Frequency, Characteristics, and Correlates of Cognitive Complaints in a Cohort of Individuals with Post-Acute Sequelae of COVID-19

BACKGROUND

Cognitive complaints are among the most frequent symptoms of post-acute sequelae of COVID-19 (PASC). This study aimed to investigate the frequency, characteristics, and clinical correlates of cognitive complaints (CC) in PASC, particularly in relation to objective neuropsychological (NP) performance.

METHODS

Seventy-four participants underwent psychiatric, medical, and NP testing approximately 7 months after acute COVID-19. The Patient Assessment of Own Functioning Inventory (PAOFI) was used to characterize the frequency and severity of CC in domains of memory, language, and cognitive/executive function. The associations of CC with sociodemographic, medical, psychiatric, and NP variables were assessed utilizing correlational analysis, logistic regression, and pairwise comparisons of those categorized as having CC vs. not having CC.

RESULTS

Taken together, approximately one-third of the study participants had clinically significant CC. Memory difficulty was the most frequent CC, although all categories were frequently endorsed. Memory and cognitive/executive complaints correlated with NP tests in these and multiple other NP domains. CC were more likely to be under-reported in those with diminished NP performance than over-reported in those without diminished performance. Acute COVID-19 symptom severity, elevated depressive symptoms, and NP tests of diminished attention and psychomotor processing speed were independent predictors of CC in logistic regression.

CONCLUSIONS

Cognitive complaints after acute COVID-19 should be taken seriously, as they are likely to reflect diminished NP performance, as well as medical, psychiatric, and functional burdens. However, patients with PASC may not accurately identify or characterize objective cognitive difficulties, so programs offering comprehensive care for patients with PASC should offer formal neuropsychological testing.

Cognitive performance in depression in low- and middle-income countries: A systematic review with meta-analytic components

BACKGROUND

Depression is highly prevalent in low- and middle- income countries (LMIC) and associated with significant cognitive dysfunction across multiple domains. However, little is known about neurocognitive tests used in people with depression in LMIC. We aimed to investigate cognitive performance and cognitive tests in depression research in LMIC.

METHODS

APA PsycInfo, Embase, Ovid MEDLINE, and Global Health were systematically searched for studies that implemented a cognitive performance test in a depressed, LMIC population. Tool quality was assessed using an adapted scale for quality of measures in cross-cultural settings. Data extracted included demographics, depression and cognitive performance measures, and cognitive performance comparisons between depression and control groups.

RESULTS

29 studies met eligibility criteria, involving a total of 19,100 participants from 11 LMIC. 93.1 % of studies were conducted in upper middle-income countries. 67 cognitive performance tools were implemented. Reliability was reported for 5.6 % of cognitive performance tests and validity was reported for 8.3 %. 36.1 % of tests used were culturally adapted. 75.9 % of included studies implemented at least one memory test. Cognitive deficits were observed in all depressed groups, especially in memory (Cohen's d = -1.60, 95 % CI -2.02 to -1.18).

LIMITATIONS

Heterogeneity between studies; averaged results across memory subtypes; no assessment of depression severity and cognitive deficits associations; restrictive search terms.

CONCLUSIONS

Cognitive impairments in depression, especially in memory, are prevalent in LMIC. This research has drawn attention to the burden of cognitive dysfunction in depression in LMIC, and to the disparate research gap in LMIC. PROSPERO registration CRD42022315397.

Educational attainment of adolescents treated in psychiatric inpatient care: a register study over 3 decades

Mental disorders may for various reasons impair educational attainment, and with far-reaching consequences given the impact of education on subsequent employment, social life, life choices and even health and mortality. This register-based study addresses trends in educational attainment among Finnish adolescents aged 13-17 with mental disorders severe enough to necessitate inpatient treatment between 1980 and 2010. Our subjects (N = 14,435), followed up until the end of 2014, were at greater risk of discontinuing education beyond compulsory comprehensive school or of lower educational attainment than their age-peers in general population. Only 50.0% had completed any post-comprehensive education compared to 84.9% in same-aged general population. Those at highest risk were males and those with organic, intellectual disabilities and developmental, externalizing disorders or schizophrenia group diagnoses. Despite improvements in adolescent psychiatric care, school welfare services and pedagogical support, risks have remained high. Greater effort in psychiatric treatment, school welfare and pedagogy are needed to combat this severe inequality.

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

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

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

ABSTRACT

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

Differences in Selective Attention and Inhibitory Control in Patients with Major Depressive Disorder and Healthy Controls Who Do Not Engage in Sufficient Physical Activity

BACKGROUND

Patients with major depressive disorder (MDD) are characterized by neurocognitive impairments and show deficits in various cognitive performance indicators, including executive function. We examined whether sustained attention and inhibitory control differ between patients with MDD and healthy controls, and whether differences exist between patients with mild, moderate, and severe depression.

METHODS

Clinical in-patients (N = 212) aged 18-65 years with a current diagnosis of MDD and 128 healthy controls were recruited. Depression severity was assessed using the Beck Depression Inventory, and sustained attention and inhibitory control were assessed using the oddball and flanker tasks. The use of these tasks promises insights into executive function in depressive patients that are not biased by verbal skills. Group differences were tested via analyses of covariance.

RESULTS

Patients with MDD showed slower reaction times in both the oddball and flanker task, independent of the executive demands of the trial types. Younger participants achieved shorter reaction times in both inhibitory control tasks. After correcting for age, education, smoking, BMI, and nationality, only differences in reaction times in the oddball task were statistically significant. In contrast, reaction times were not sensitive to the symptom severity of depression.

CONCLUSION

Our results corroborate deficits in basic information processing and specific impairments in higher-order cognitive processes in MDD patients. As difficulties in executive function underlie problems in planning, initiating, and completing goal-directed activities, they may jeopardize in-patient treatment and contribute to the recurrent nature of depression.

Cognitive Impairment Mechanism in Patients with Bipolar Disorder

Bipolar disorder (BD) is a common chronic mental disorder usually characterized by manic, hypomanic and depressive episodes. Patients diagnosed with BD have cognitive impairments in both the mood attack and remission stages, that is impairment of attention, memory and executive function. Up till the present moment, the causative mechanisms of cognitive impairment in BD patients remain poorly understood. Several studies have demonstrated that cognitive impairment in patients with bipolar disorder is not associated with a single factor, but with gene polymorphism, brain structural and functional variables, inflammatory and metabolic factors. Herein, we reviewed and summarized the recent reports on cognitive impairment mechanisms in patients with BD. To prevent or alleviate cognitive damage at an early stage, we propose that future research should focus on investigating the pathological mechanism of specific cognitive dimension damage as well as the pathological mechanism network between the damage of each dimension. It is crucial to recognize mechanisms of cognitive impairment for improving the symptoms and prognosis of BD patients, restoring their social function and integration.

Pro-inflammatory cytokines and cognitive dysfunction among patients with bipolar disorder and major depression

AIM

Bipolar disorder and major depressive disorder (MDD) have been demonstrated to be associated with proinflammatory states and cognitive function deficits. We aimed to investigate the differences of cognitive function and proinflammatory cytokines between patients with bipolar I disorder (BDI), bipolar II disorder (BDII), and MDD.

METHODS

Thirty-seven patients with BDI, 33 with BDII, 25 with MDD, and 54 age-, sex-matched controls were enrolled. All patients had a clinical global impression-severity scale ≤2. Serum levels of proinflammatory markers, including soluble interleukin-6 receptor, C-reactive protein, and soluble tumor necrosis factor receptor 1 (sTNF-αR1) were measured. Performance in the Word List Memory Task (WLMT), Wisconsin Card Sorting Task (WCST), 2-back task, Go/No-Go task, and divided attention task was assessed.

RESULTS

Patients with BDI had higher levels of sTNF-αR1 than patients with MDD and controls (P < 0.001). Patients with BDI performed worse on WLMT, WCST, 2-back task, divided attention_visual and divided attention_auditory tasks than the other three groups (all P < 0.05). Furthermore, sTNF-αR1 levels were negatively correlated with cognitive function measured using the WLMT and divided attention_auditory (all P < 0.05).

CONCLUSIONS

Patients with BDI had higher levels of sTNF-αR1 and cognitive function impairments than the remaining groups. Future studies are needed to explore the pathophysiology of sTNF-αR1 in the contribution of cognitive alterations.

Neurocognitive deficits in depression: a systematic review of cognitive impairment in the acute and remitted state

Previous research suggests a broad range of deficits in major depressive disorder. Our goal was to update the current assumptions and investigate the extent of cognitive impairment in depression in the acute and remitted state. A systematic review of the existing literature between 2009 and 2019 assessing the risk of bias within the included studies was performed. Of the 42 articles reviewed, an unclear risk of bias was shown overall. The risk of bias mainly concerned the sample selection, inadequate remedial measures, as well as the lack of blinding the assessors. In the acute phase, we found strong support for impairment in processing speed, learning, and memory. Follow-up studies and direct comparisons revealed less pronounced deficits in remission, however, deficits were still present in attention, learning and memory, and working memory. A positive correlation between the number of episodes and cognitive deficits as well as depression severity and cognitive deficits was reported. The results also demonstrate a resemblance between the cognitive profiles in bipolar disorder and depression. Comparisons of depression with schizophrenia led to unclear results, at times suggesting an overlap in cognitive performance. The main findings support the global deficit hypothesis and align with results from prior meta-analyses and reviews. Recommendations for future research are also presented.

The prevalence and characteristics of MCCB cognitive impairment in unmedicated patients with bipolar II depression and major depressive disorder

BACKGROUND

Cognitive impairment has been acknowledged as a core clinical manifestation of bipolar disorder (BD) as well as major depressive disorder (MDD). Determining the prevalence and characteristics of cognitive impairment is important for clinical interventions. This study investigated the prevalence and characteristics of cognitive impairment based on the Measurement and Treatment Research to Improve Cognition Schizophrenia Consensus Cognitive Battery (MCCB) in both BD and MDD.

METHOD

One hundred and forty-nine BD II depression, 147 MDD, and 124 demographically matched healthy controls (HC) underwent MCCB cognitive assessment. The prevalence of MCCB cognitive impairment and group difference comparisons were performed. Additionally, association analysis was performed to investigate the relationship between cognitive performance and clinical variables.

RESULTS

Compared to the HC group, both BD II depression and MDD groups had a significantly reduced performance for all MCCB cognitive domains (all p < 0.05). The numerical scores for visual learning were lower in the BD II depression group compared to the MDD group. 32.89% of the BD II depression patients had clinically significant impairment (>1.5 SD below the normal mean) in two or more MCCB domains compared to 23.13% for MDD patients.

CONCLUSIONS

A high percent of patients in the BD II depression and MDD group exhibited MCCB cognitive impairments with clinical significance. Cognitive impairments were more common in BD II depression patients compared to MDD patients, particularly for visual learning. These findings suggest that clinicians should be aware of the severe cognitive impairment in mood disorders and establish effective cognitive screening and intervention strategies.

Cold Cognition as Predictor of Treatment Response to rTMS; A Retrospective Study on Patients With Unipolar and Bipolar Depression

Background

Cognitive impairments are prevalent in patients with unipolar and bipolar depressive disorder (UDD and BDD, respectively). Considering the fact assessing cognitive functions is increasingly feasible for clinicians and researchers, targeting these problems in treatment and using them at baseline as predictors of response to treatment can be very informative.

Method

In a naturalistic, retrospective study, data from 120 patients (Mean age: 33.58) with UDD (n = 56) and BDD (n = 64) were analyzed. Patients received 20 sessions of bilateral rTMS (10 Hz over LDLPFC and 1 HZ over RDLPFC) and were assessed regarding their depressive symptoms, sustained attention, working memory, and executive functions, using the Beck Depression Inventory (BDI-II) and Neuropsychological Test Automated Battery Cambridge, at baseline and after the end of rTMS treatment course. Generalized estimating equations (GEE) and logistic regression were used as the main statistical methods to test the hypotheses.

Results

Fifty-three percentage of all patients (n = 64) responded to treatment. In particular, 53.1% of UDD patients (n = 34) and 46.9% of BDD patients (n = 30) responded to treatment. Bilateral rTMS improved all cognitive functions (attention, working memory, and executive function) except for visual memory and resulted in more modulations in the working memory of UDD compared to BDD patients. More improvements in working memory were observed in responded patients and visual memory, age, and sex were determined as treatment response predictors. Working memory, visual memory, and age were identified as treatment response predictors in BDD and UDD patients, respectively.

Conclusion

Bilateral rTMS improved cold cognition and depressive symptoms in UDD and BDD patients, possibly by altering cognitive control mechanisms (top-down), and processing negative emotional bias.

Features of cognitive impairment and related risk factors in patients with major depressive disorder: A case-control study

BACKGROUND

Cognitive impairment (CI) is a common symptom contributing to functional loss in major depressive disorder (MDD). However, the features of CI and its related risk factors in young and middle-aged MDD patients remain unclear.

METHODS

In this case-control study, 18- to 55-year-old acute-onset MDD patients and healthy controls (HCs) were recruited from nine centers in China. MDD patients were diagnosed based on the DSM-IV, the Mini-International Neuropsychiatric Interview, and a 17-item Hamilton Rating Scale for Depression score ≥ 14. Cognitive function, including attention/vigilance, learning, memory, processing speed and executive function, was assessed with a neuropsychological battery and compared between MDD patients and HCs. MDD patients scoring 1.5 SDs below the mean HC score in at least 2 domains were defined as having CI. Logistic regression analysis was used to identify risk factors for CI in MDD patients.

RESULTS

Compared with HCs (n = 302), MDD patients (n = 631) showed significant impairment in all cognitive domains (P < 0.001); 168 MDD patients (26.6%) had CI. Male sex (OR: 1.712; 95% CI: 1.165-2.514; P < 0.01) was positively correlated with CI; age of first onset (OR: 0.974; 95% CI: 0.957-0.991; P < 0.05) and comorbid anxiety disorders (OR: 0.514; 95% CI: 0.332-0.797; P < 0.01) were negatively correlated with CI.

LIMITATIONS

Biomarkers and neuroimaging were not used to investigate the possible biological mechanism and neural basis of CI in MDD.

CONCLUSIONS

CI was prominent in adults with acute-onset MDD; male sex and younger age of first onset were independent risk factors, and comorbid anxiety disorders were a protective factor.

Comparison of cognitive impairments with lipid profiles and inflammatory biomarkers in unipolar and bipolar depression

Cognitive impairments is one of important accompanied symptom in Unipolar depressive disorder (UD) and bipolar disorder (BD) that was hard to distinguish, as their diagnosis is based on behavioural observations and subjective symptoms. In this study, we could highlight the difference of cognitive ability in UD and BD by testing lipid profiles and inflammatory biomarkers in major depressive episodes (MDE). 207 subjects (96 unipolar and 111 bipolar depressed patients) were included in this study. We applied Montreal Cognitive Assessment (MoCA) to test cognitive ability. The 24-item Hamilton Depression Rating Scale was used for assessment at the beginning of treatment. A series of clinical variables and lipid profiles were collected from clinic record. We detected pro-inflammatory biomarkers Interleukin-1β (IL-1β), Interleukin-6 (IL-6), C-reaction protein (CRP) levels and brain-derived neurotrophic factor (BDNF) by enzyme linked immunosorbent assay. From the results, cognitive impairments were more popular in BD than UD, most obviously in severe cognitive impairments (MoCA score<23). And UD showed better cognitive ability than BD in MoCA, particularly in language domain. Compared lipid profiles like total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (ApoA1), Apolipoprotein B (ApoB) and lipoprotein α (Lpα), we found that ApoB was higher in BD than UD that maybe a risk factor in cognition. There was no obviously difference in TC, TG, HDL-C, LDL-C, ApoA1, or Lpα. Also, we found CRP level in BD was higher than UD, and showed no significant difference in IL-1β and IL-6 levels. Furthermore, BDNF level which was neurotrophic biomarker for cognition and mood was significantly declined in BD compared with UD. Correlation analysis showed that ApoB and CRP was negative closed associated with MoCA scores. And BDNF level was positive related with cognitive ability in MDE patients. From our results mentioned that quantitative lipid profiles and inflammatory biomarkers analysis might help to objectively identify between these disorders and up our understanding of their pathophysiology. And ApoB, CRP and BDNF could be as potential peripheral candidates in cognitive evaluation to distinguish UD and BD.

Pharmacological interventions to diminish cognitive side effects of electroconvulsive therapy: A systematic review and meta-analysis

OBJECTIVE

The authors conducted a systematic review and meta-analysis of pharmacological interventions to diminish cognitive side effects of ECT.

METHODS

Electronic databases of Pubmed, PsycInfo, Embase and Scopus were searched from inception through 1 April, 2021, using terms for ECT (e.g. electroconvulsive therapy), cognitive outcome (e.g. cogni*) and pharmacological intervention (e.g. calcium channel blocker and general terms, like protein). Original studies with humans receiving ECT were included, which applied pharmacological interventions in comparison with placebo or no additive intervention to diminish cognitive side effects. Data quality was assessed using Risk of Bias and GRADE. Random-effects models were used. PROSPERO registration number was CRD42021212773.

RESULTS

Qualitative synthesis (systematic review) showed 52 studies reporting sixteen pharmacological intervention-types. Quantitative synthesis (meta-analysis) included 26 studies (1387 patients) describing twelve pharmacological intervention-types. Low-quality evidence of efficacy was established for memantine (large effect size) and liothyronine (medium effect size). Very low-quality evidence shows effect of acetylcholine inhibitors, piracetam and melatonin in some cognitive domains. Evidence of no efficacy was revealed for ketamine (very low-quality), herbal preparations with anti-inflammatory properties (very low to low-quality) and opioid receptor agonists (low-quality).

CONCLUSION

Memantine and liothyronine are promising for further research and future application. Quality of evidence was low because of differences in ECT techniques, study populations and cognitive measurements. These findings provide a guide for rational choices of potential pharmacological intervention research targets to decrease the burden of cognitive side effects of ECT. Future research should be more uniform in design and attempt to clarify pathophysiological mechanisms of cognitive side effects of ECT.

Single episode brief psychotic disorder versus bipolar disorder: A diffusion tensor imaging and executive functions study

BACKGROUND

Despite fast progress in neuroscientific approaches, the neurobiological continuum links psychotic spectrum, and affective disorder is obscure. White matter WM abnormalities found utilizing Diffusion Tensor Imaging (DTI) showing impaired communication in both disorders have been consistently demonstrated; however, direct comparisons of findings between them are scarce. This study aims to study WM abnormalities in single episode bipolar I disorder, and single episode brief psychotic disorder related to healthy control with the association of executive function.

METHODS

A cross-sectional case-control study was used to assess 60 subjects divided into 20 patients with single episode bipolar I disorder, 20 individuals with single episode brief psychotic disorder (both groups of patients were in remission), and 20 healthy controls. The present study examined the superior longitudinal fasciculus (SLF), and cingulum bundle fractional anisotropy (FA) determined from DTI images symmetrically and connected these results with cognitive functions as assessed by the trail making test (TMT) and Wisconsin card sorting test (WCST).

RESULTS

DTI data indicated that the psychotic group had a significant decrease in FA of the right SLF (p-value less than 0.001), left SLF (p-value less than 0.001), and left cingulum (p-value less than 0.001) than the bipolar I group. In terms of executive functioning, the psychotic group performed significantly worse than the bipolar I group on the TMT part B (p-value less than 0.001), the WCST (number of classifications fulfilled) (p-value less than 0.001), and perseverative errors (p-value less than 0.001).

CONCLUSION

Even after clinical remission, individuals with single episode brief psychotic disorder had more pronounced white matter impairments and executive function deficiencies than individuals with single episode bipolar I disorder.

BIPOLAR DISORDER, MOOD STABILIZERS AND COGNITIVE FLEXIBILITY: TRANSLATIONALLY DISSECTING ILLNESS FROM DRUG EFFECTS

Bipolar disorder (BD) effects on cognition are confounded by the putative cognitive impact of its major pharmacological treatments, given the neurotrophic potential of mood stabilizers, particularly lithium. We examined the area of cognitive flexibility (CF), aiming to disentangle BD from medication effects, using translational methodology. CF was assessed by CANTAB-IED (intra- extra-dimensional shift; Study 1, euthymic BD participants) and its animal analogue (Study 2, rats). Both studies included groups (1) control, (2) lithium, chronic, current treatment (LI-CHRON-C, A: >2 years, N=32; B: 2 months, N=11); (3) valproate, chronic, current treatment (VPA-CHRON-C, A: >2 years, N=30; B: 2 months, N=12). Study 2 included 2 additional groups; Group 4: LI-CHRON-PAST (2 months, stopped 1 month pretest, N=13); Group 5: LI-ACUTE (LI on test days only, N=13). In Study 1, neither total nor stage (discrimination: D; reversal R; intra- extra-dimensional shifts: IED) IED errors differed between groups [(Kruskal-Wallis: H(2, N= 94) 0.95 > p > 0.65]. Similarly in Study 2, errors did not differentiate the 5 pharmacological groups. Differences emerged only between LI-ACUTE and Controls in response latencies (D, R, IED ANOVAS: 0.002 > p > 0.0003; contrasts D, R: p = 0.002, 0.0001). In conclusion, LI and VPA BD patients were indistinguishable from Controls in IED errors, as were animals treated with LI-CHRON, current or past, or VPA-CHRON-C vs Controls. LI-ACUTE treatment produced significant latency deficits vs. Controls. Within the limitations of translational comparisons, our results suggest that the normal CF noted in euthymic BDs is not attributable to mood stabilizer effects.

Neuropsychological exponents for the driving ability in remitted bipolar patients

Background

Bipolar disorder (BD) is associated with cognitive deficits regardless of the phase of the disease. Medications used in treatment are an additional factor that may affect cognitive performance. Poor cognitive performance can significantly affect a patient's ability to drive.

Aim of the study

This study aims to explore cognitive functions relevant for safe driving in the group of remitted bipolar patients.

Method

Patients with BD in remission (n = 33) and healthy volunteers (n = 32) were included. Selected psychometric tests for drivers were carried out using computer software: called Specialistic Diagnostic Platform (SPD): The Cross-over Test (COT) version with free tempo (COT-F) and tempo of 50 tasks per minute (COT-50) and the Signal Test (ST). Moreover, the following neuropsychological tests were used: Rey Auditory Verbal Learning Test (RAVLT), Stroop Color-Word Test (SCWT) part A and B, and Trail Making Test (TMT) version A and B.

Results

In comparison with healthy controls bipolar patients in remission had poorer outcomes for some cognitive parameters and longer reaction times in both tests for drivers and neuropsychological tests. Additionally, we found a significant correlation between the time of performance of neuropsychological tests and the time of psychometric tests for drivers.

Conclusion

Patients with BD performed worse in several cognitive domains assessed by tests for drivers and neuropsychological tasks. These deficits can affect the speed of the patient's motor reactions while driving.

Cognitive Impairment and Neurocognitive Profiles in Major Depression-A Clinical Perspective

Increasingly, studies have investigated cognitive functioning from the perspective of acute state- to remitted phases of Major Depressive Disorder (MDD). Some cognitive deficits observed in the symptomatic phase persist in remission as traits or scars. The etiological origin and clinical consequences of the neurocognitive profiles reported in the literature are still unclear and may vary across populations. Deficits are suspected to influence the association between MDD and neurodegenerative disorders and could thus be of particular clinical consequence. The aim of this review is to describe the clinical neuropsychological profile in MDD and how it is related to research during the past decade on cognitive deficits in MDD from a state, trait, and scar perspective. This review, with a clinical perspective, investigates research from the past decade regarding cognitive functioning in MDD in a long-term perspective. We focus on the clinical manifestation of deficits, and the potential neurodegenerative consequences of the neurocognitive profile in MDD. Searches in Medline, PsycINFO and Embase were conducted targeting articles published between 2010 and 2020. Examination of the evidence for long-lasting neurocognitive deficits in major depression within the cognitive domains of Memory, Executive Functions, Attention, and Processing Speed was conducted and was interpreted in the context of the State, Scar and Trait hypotheses. Defining the neurocognitive profiles in MDD will have consequences for personalized evaluation and treatment of residual cognitive symptoms, and etiological understanding of mood disorders, and treatments could potentially reduce or delay the development of neurodegenerative disorders.

Neuropsychological, medical and psychiatric findings after recovery from acute COVID-19: A cross-sectional study

Background

Objective

Methods

Results

Conclusion

Low BDNF levels in serum are associated with cognitive impairments in medication-naïve patients with current depressive episode in BD II and MDD

OBJECTIVE

This study aimed to investigate the role of Brain-derived neurotrophic factor (BDNF) in clinical and cognitive outcomes in medication-naïve patients with Bipolar type II disorder (BD II) and Major depressive disorder (MDD).

METHODS

45 outpatients with BD II, 40 outpatients with MDD and 40 healthy controls (HCs) were recruited, and sociodemographic and clinical data were collected. Their BDNF serum levels were measured and analyzed with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

RESULTS

BDNF levels were significantly lower in BD II patients than in MDD patients and HCs (p = 0.001). BD II and MDD patients had similar cognitive performance deficits shown on Attention (p = 0.001), Delayed memory (p = 0.001), and RBANS total score (p = 0.001). BDNF levels were positively associated with Visuospatial / constructional and Stroop color-word in BD II group, and with language in MDD group. The area under the curve (AUC) of the ROC analysis in BD II vs. MDD was 0.664, therefore, BDNF levels could not distinguish BD II from MDD.

CONCLUSION

Our study showed the decreased serum BDNF in MDD and BD II patients, suggesting BDNF may be involved in the pathophysiology of MDD and BD II. BDNF and cognitive deficits are both of low efficiency in distinguishing BD II from MDD. Decrease of BDNF may potentially indicate cognitive dysfunction in BD II and MDD patients with a current depressive episode.

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

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

Cognitive Profile and Relationship with Quality of Life and Psychosocial Functioning in Mood Disorders

BACKGROUND

Comparisons between healthy controls (HCs) and individuals with mood disorders have shown more cognitive dysfunction among the latter group, in particular in bipolar disorder (BD). This study aimed to characterize the pattern of cognitive function of BD and major depressive disorder (MDD) and compare them to HC using the (CogState Research Battery) CSRB™.

METHOD

Participants were tested, comprising the following domains: processing speed, attention, working memory, visual memory, executive functions, and verbal memory. Quality of life and functionality were also assessed. Multiple linear regression models were performed to examine the effect of demographic characteristics and functionality on cognitive outcomes separately for BD and MDD.

RESULTS

Ninety individuals participated in the study, of which 32 had BD, 30 had MDD, and 28 were HC. Differences were found between both BD and MDD and HC for the composite cognitive score, with significant differences between BD and HC (Diff = -5.5, 95% CI = [-9.5, -1.5], p = 0.005), and MDD and HC (Diff = -4.6, 95% CI = [-8.6, -0.5], p = 0.025). There were overall significant differences in five cognitive domains: processing speed (p = 0.001 and p = 0.004), attention (p = 0.002), working memory (p = 0.02), visual memory (p = 0.021), and verbal memory (p = 0.007). BD also presented worse performance than both MDD and HC, and MDD presented better performance than BD but worse than HC in quality of life and functionality. Multiple linear regression models were significative for education (p < 0.001) and age (p = 0.004) for BD and education (p < 0.001) for MDD.

CONCLUSION

In general, cognition is more affected in BD than MDD, which could be associated with functional and quality of life impairment.

[Cognitive impairment in remitted patients with bipolar disorder]

OBJECTIVE

To assess the frequency and severity of cognitive impairment as well as its correlations with clinical characteristics in remitted patients with bipolar disorder (BD).

MATERIAL AND METHODS

Eighty-five patients with BD type I (64 patients) and BD type II (21 patients) in remission were examined (average age 36.6±5.7). Affective symptoms were assessed using the Hamilton Depression Rating Scale (HDRS) and Young's Mania Rating Scale (YMRS). Cognitive impairment was assessed using the Brief Neuropsychological Cognitive Examination (BNCE).

RESULTS

Cognitive impairment was revealed in 43.5% of the patients. The frequency and structure of cognitive impairment in patients with BD type I and type II did not differ. The patients with cognitive impairment were characterized by decreased speed of mental processes, decreased working memory and attention deficit. The correlation of the total BNCE score with the age of the patients, duration of the disease, total HDRS and YMRS scores was revealed.

CONCLUSION

The results demonstrate the affective nature of cognitive deficit in the patients. Cognitive impairment in remitted patients with BD is a significant therapeutic target.

Grey and white matter alteration in euthymic children with bipolar disorder: a combined source-based morphometry (SBM) and voxel-based morphometry (VBM) study

Bipolar disorder (BPD) is a psychiatric condition driving frequent mood swings between periodic extremes of happiness and depression in patients. In this study, a source-based morphometry (SBM) and voxel-based morphometry (VBM) analysis was utilized to measure the differences in the white matter (WM) and grey matter (GM) between euthymic children with BPD and typically developing (TD) children. We adapted both multivariate (SBM) and univariate (VBM) analysis in 20 children with BPD euthymia /remission and compared to the same number of TD age-matched children. The VBM did not reveal any increase in GM and WM voxel values in children with BPD. However, a decrease in the GM voxel values in the bilateral middle frontal and WM voxels in the left hippocampus, left caudate, left orbitofrontal and right inferior parietal cortices was identified. Conversely, SBM analysis in BPD displayed a high GM value in bilateral angular gyrus, bilateral inferior temporal, left supplementary motor area and left middle temporal region, while a low value was observed in left inferior and middle occipital, cerebellum, thalamus, left premotor area and left lingual gyrus. These findings suggested a crucial GM and WM alteration in multiple neural regions in BPD children even during sustained and substantial remission.

Transdiagnostic comparison of visual working memory capacity in bipolar disorder and schizophrenia

BACKGROUND

Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies. However, it has not yet been investigated across the full spectrum of both disorders. The aim of our study was to compare the degree of reductions of visual working memory capacity in patients with bipolar disorder (PBD) and patients with schizophrenia (PSZ) using a paradigm well established in cognitive neuroscience.

METHODS

62 PBD, 64 PSZ, and 70 healthy controls (HC) completed a canonical visual change detection task. Participants had to encode the color of four circles and indicate after a short delay whether the color of one of the circles had changed or not. We estimated working memory capacity using Pashler's K.

RESULTS

Working memory capacity was significantly reduced in both PBD and PSZ compared to HC. We observed a small effect size (r = .202) for the difference between HC and PBD and a medium effect size (r = .370) for the difference between HC and PSZ. Working memory capacity in PSZ was also significantly reduced compared to PBD with a small effect size (r = .201). Thus, PBD showed an intermediate level of impairment.

CONCLUSIONS

These findings provide evidence for a gradient of reduced working memory capacity in bipolar disorder and schizophrenia, with PSZ showing the strongest degree of impairment. This underscores the importance of disturbed information processing for both bipolar disorder and schizophrenia. Our results are compatible with the cognitive manifestation of a neurodevelopmental gradient affecting bipolar disorder to a lesser degree than schizophrenia. They also highlight the relevance of visual working memory capacity for the development of both behavior- and brain-based transdiagnostic biomarkers.

Performance on the Wechsler Adult Intelligence Scale (WAIS) in Japanese patients with bipolar and major depressive disorders in euthymic and depressed states

AIM

This study aimed to examine the cognitive performance of patients with bipolar disorder (BD) stratified by illness phase compared to that of patients with major depressive disorder (MDD) and healthy controls.

METHODS

Participants were 139 patients with BD (55 euthymic and 84 depressed), 311 patients with MDD (88 euthymic and 223 depressed), and 386 healthy controls who underwent the Wechsler Adult Intelligence Scale-Revised or the Third Edition. They were non-elderly Japanese individuals with normal estimated premorbid intelligence quotient (IQ; >90), group-matched for age, sex, and premorbid IQ.

RESULTS

The depressed BD group showed significantly lower scores on verbal IQ, performance IQ, full-scale IQ, and three group indexes of perceptual organization, working memory, and processing speed when compared with healthy controls (all P < 0.001). All IQs and working memory index were also significantly lower than those of the depressed MDD group. The depressed MDD group scored significantly lower than controls in performance IQ (P < 0.001), full-scale IQ, and only in the index of processing speed (P < 0.001). The euthymic BD group scored significantly lower than controls in performance IQ (P = 0.004), whereas the euthymic MDD group scored significantly lower than controls only in processing speed (P = 0.030).

CONCLUSION

Patients with BD appear to have global and more intense cognitive impairments in depressed states compared with those with MDD whose impairments seem to be apparent only in processing speed in the Wechsler Adult Intelligence Scale. Attenuated impairments appear to exist in euthymic states of both patients.

Cortical mediation of relationships between dopamine receptor D2 and cognition is absent in youth at risk of bipolar disorder

Bipolar disorder is associated with cognitive deficits and cortical changes for which the developmental dynamics are not well understood. The dopamine D2 receptor (DRD2) gene has been associated with both psychiatric disorders and cognitive variability. Here we examined the mediating role of brain structure in the relationship between DRD2 genomic variation and cognitive performance, with target cortical regions selected based on evidence of association with DRD2, bipolar disorder and/or cognition from prior literature. Participants (n = 143) were aged 12-30 years and comprised 62 first-degree relatives of bipolar patients (deemed 'at-risk'), 55 controls, and 26 patients with established bipolar disorder; all were unrelated Caucasian individuals with complete data across the three required modalities (structural magnetic resonance imaging, neuropsychological and genetic data). A DRD2 haplotype was derived from three functional polymorphisms (rs1800497, rs1076560, rs2283265) associated with alternative splicing (i.e., D2-short/-long isoforms). Moderated mediation analyses explored group differences in relationships between this DRD2 haplotype, three structural brain networks which subsume the identified cortical regions of interest (frontoparietal, dorsal-attention, and ventral-attention), and three cognitive indices (intelligence, attention, and immediate memory). Controls who were homozygous for the DRD2 major haplotype demonstrated greater cognitive performance as a result of dorsal-attention network mediation. However, this association was absent in the 'at-risk' group. This study provides the first evidence of a functional DRD2-brain-cognition pathway. The absence of typical brain-cognition relationships in young 'at-risk' individuals may reflect biological differences that precede illness onset. Further insight into early pathogenic processes may facilitate targeted early interventions.

Age-related white matter changes revealed by a whole-brain fiber-tracking method in bipolar disorder compared to major depressive disorder and healthy controls

AIM

Several studies have reported altered age-associated changes in white matter integrity in bipolar disorder (BD). However, little is known as to whether these age-related changes are illness-specific. We assessed disease-specific effects by controlling for age and investigated age-associated changes and Group × Age interactions in white matter integrity among major depressive disorder (MDD) patients, BD patients, and healthy controls.

METHODS

Healthy controls (n = 96; age range, 20-77 years), MDD patients (n = 101; age range, 25-78 years), and BD patients (n = 58; age range, 22-76 years) participated in this study. Fractional anisotropy (FA) derived from diffusion tensor imaging in 54 white matter tracts were compared after controlling for the linear and quadratic effect of age using a generalized linear model. Age-related effects and Age × Group interactions were also assessed in the model.

RESULTS

The main effect of group was significant in the left column and body of the fornix after controlling for both linear and quadratic effects of age, and in the left body of the corpus callosum after controlling for the quadratic effect of age. BD patients exhibited significantly lower FA relative to other groups. There was no Age × Group interaction in the tracts.

CONCLUSION

Significant FA reductions were found in BD patients after controlling for age, indicating that abnormal white matter integrity in BD may occur at a younger age rather than developing progressively with age.

Relationships Among History of Psychosis, Cognition and Functioning in Later-Life Remitted Major Depression

OBJECTIVE

This study tested the hypotheses that, in older adults with remitted major depression, a history of psychotic features and poorer neuropsychological performance would be independently associated with poorer everyday functioning, but that neuropsychological performance would explain more of the variance in functioning than history of psychotic features.

METHODS

This cross-sectional study included 73 patients aged 50 years or older with remitted psychotic major depression or nonpsychotic major depression. The dependent variables were subjective and objective measures of function. The independent variables were history of psychotic features during one or more major depressive episodes in the previous 10 years and neuropsychological performance. Linear regression models examined the association of independent variables with function, controlling for pertinent covariates. Effect sizes were calculated for the magnitude of difference in function between the patient participants and an age- and gender-matched nonpsychiatric group, and distribution of functioning scores were compared between groups.

RESULTS

In separate models, history of psychotic features and poorer processing speed, executive function, and verbal learning were independently associated with poorer participant-reported functioning and performance-based functioning. However, the association of psychotic features with functioning was no longer statistically significant when tested in the same models as neuropsychological measures. Effect sizes of the difference in functioning between patients and the nonpsychiatric group were significantly larger for the remitted psychotic than the remitted nonpsychotic depression group; functioning scores were more heterogeneous in the remitted psychotic depression group.

CONCLUSION

Patients with remitted psychotic depression exhibit greater, and clinically important, impairment in everyday functioning than those with remitted nonpsychotic depression. Neuropsychological impairment appears to contribute to this relationship.

Examination and Comparison of Cognitive and Executive Functions in Clinically Stable Schizophrenia Disorder, Bipolar Disorder, and Major Depressive Disorder

BACKGROUND

Schizophrenia (SC), bipolar disorder (BD), and major depressive disorder (MDD) are associated with various cognitive and executive dysfunctions. The aim of the present study was to evaluate and compare cognitive and executive dysfunctions in schizophrenia, bipolar disorder, and major depressive disorder.

MATERIALS AND METHODS

Sixty-four schizophrenia patients, 68 bipolar patients, 62 patients with major depressive disorder, and 75 healthy individuals participated in the present study. All participants were assessed with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), Young Mania Rating Scale (YMRS), Positive and Negative Syndrome Scale (PANSS), Beck Depression Inventory (BDI-II), Trial Making Test (TMT), Four-Choice Reaction Time Task, Ruler Drop Method (RDM), Tower of London (TOL) task, and the Wisconsin Card Sorting Task (WCST). Data were analyzed by chi-square, Kolmogorov-Smirnov, and independent t-tests; ANOVA; and MANOVA.

RESULTS

In the cognitive function, the scores of SC, BD, and MDD patients were lower than those of healthy individuals. Also, the scores of MDD patients were lower than those of other patients, and the scores of BD patients were lower than those of SC patients. In the executive function, the scores of SC, BD, and MDD patients were lower than those of healthy individuals. Moreover, the scores of the MDD group were higher than those of the BD and SC groups, and the scores of the SC group were higher than those of the BD group.

CONCLUSION

Patients with SC, BD, and MDD have poorer cognitive and executive functions than healthy individuals, even when these patients are in a stable state. Assessment of cognitive and executive functions in SC, BD, and MDD patients can help in understanding the pathology of these disorders.

White matter abnormalities and cognitive function in euthymic patients with bipolar disorder and major depressive disorder

OBJECTIVES

In recent years, a growing number of diffusion tensor imaging (DTI) studies have compared white matter integrity between patients with major depressive disorder (MDD) and bipolar disorder (BD). However, few studies have examined the pathophysiological significance of different degrees of white matter abnormalities between the two disorders. The present study comprehensively assessed white matter integrity among healthy controls (HC) and euthymic patients with MDD and BD using whole-brain tractography and examined associations between white matter integrity and cognitive functioning.

METHODS

We performed neurocognitive examinations and DTI with 30 HCs, 30 patients with MDD, and 30 patients with BD. We statistically evaluated white matter integrity and cognitive function differences across the three groups, assessing associations between white matter integrities and cognitive function.

RESULTS

The BD group showed lower fractional anisotropy (FA) for the corpus callosum body, as well as lower, sustained attention and set-shifting scores compared to the other groups. FA for the left body of the corpus callosum was correlated with sustained attention in patients with BD.

CONCLUSIONS

The significant reduction of white matter integrity in the corpus callosum in BD, compared to MDD, was associated with an impairment of sustained attention. This result promotes the understanding of the significance of white matter integrity in mood disorders.

Duration of untreated illness and depression severity are associated with cognitive impairment in mood disorders

Introduction: In this study we estimated the rate and the trajectory of cognitive impairment in a naturalistic sample of outpatients with major depressive disorder (MDD) and bipolar disorder (BD) and its correlation with different variables.Materials and methods: An overall sample of 109 outpatients with MDD or BD was assessed for multiple clinical variables, including duration of untreated illness (DUI), and tested using the Montreal Cognitive Assessment (MoCA) during Major Depressive Episodes (MDE) and after remission. Correlations between MoCA scores and the clinical variables were then computed.Results: About 50% of patients with MDD and BD showed mild cognitive impairment during MDE. Improvement of cognitive function between depression and remission was significant, even though residual symptoms were observed especially in the most impaired patients. Of note, cognitive performance during depression was negatively associated with depression severity and DUI.Discussion: Present findings confirm available evidence about patterns of cognitive impairment in mood disorders, in terms of prevalence and persistence beyond remission in most severe cases. Moreover, a longer DUI was associated with worse cognitive performance during depression, and consequently with poorer outcome, underlining the importance of prompt treatment of these disorders also in light of a cognitive perspective.KeypointsAlthough distinct entities, unipolar and bipolar depression determine similar patterns of cognitive impairment in terms of severity and types of altered domains.Depression (but not anxiety) severity is associated with cognitive performance in depression.Prolonged duration of untreated illness is associated with more severe cognitive impairment during depression, particularly but not specifically in bipolar disorder.

Neuropsychology of Bipolar Disorder

Bipolar disorder is associated with significant dysfunction in a broad range of neuropsychological domains and processes. Deficits have been reported to occur in symptomatic states (depression, [hypo]mania) as well as in remission (euthymia), having consequences for psychological well-being and social and occupational functioning. The profile and magnitude of neuropsychological deficits in bipolar disorder have been explored in a number of systematic reviews and meta-analyses. After discussing these briefly, this chapter will focus on examining the clinical and demographic factors that influence and modify the pattern and magnitude of deficits, as well as reviewing methods of assessment and analysis approaches which may improve our understanding of these problems.

Using network analysis to explore cognitive domains in patients with unipolar versus bipolar depression: a prospective naturalistic study

OBJECTIVE

Despite growing evidence in the field of cognitive function in mood disorders, the neurocognitive profiles of patients with unipolar and bipolar depression still need further characterization. In this study, we applied network analysis, hypothesizing this approach could highlight differences between major depressive disorder (MDD) and bipolar disorder (BD) from a cognitive perspective.

METHODS

The cognitive performance of 109 patients (72 unipolar and 37 bipolar depressed outpatients) was assessed through the Montreal Cognitive Assessment (MoCA), and a series of clinical variables were collected. Differences in cognitive performance between MDD and BD patients were tested using non-parametric tests. Moreover, a network graph representing MoCA domains as nodes and Spearman's rho correlation coefficients between the domains as edges was constructed for each group.

RESULTS

The presence of mild cognitive impairment was observed in both MDD and BD patients during depression. No statistical significant difference was found between the two groups in terms of overall cognitive performance and across single domains. Nonetheless, network analytic metrics demonstrated different roles of memory and executive dysfunction in MDD versus BD patients: in particular, MDD network was more densely interconnected than BD network, and memory was the node with the highest betweenness and closeness centrality in MDD, while executive function was more central in BD.

CONCLUSIONS

From a network analytic perspective, memory impairment displays a central role in the cognitive impairment of patients with unipolar depression, whereas executive dysfunction appears to be more central in bipolar depression. Further research is warranted to confirm our results.

Psychometric properties of the MATRICS Consensus Cognitive Battery (MCCB) in Chinese patients with major depressive disorder

BACKGROUND

Major depression disorder (MDD) is often associated with cognitive impairment. The development of an accurate and effective battery to measure cognitive deficit is necessary for both research and clinical practice in MDD. Our study was designed to test the psychometric properties of the MATRICS Consensus Cognitive Battery (MCCB) in patients with MDD.

METHOD

Forty-eight patients with MDD, forty-three euthymic patients with bipolar disorder (BD) and thirty-two remitted patients with schizophrenia (SCH) were recruited from Tianjin Anding Hospital in Tianjin, China. The MCCB, the Montreal Cognitive Assessment (MoCA) and the Hamilton Depression Rating Scale-17 (HDRS-17) were administered to assess cognitive impairment and depressive symptoms at both baseline and one month later.

RESULT

Our findings showed that the MCCB had good internal consistency and acceptable reliability in Chinese MDD patients. Our findings revealed a high correlation between the MCCB and the MoCA, indicating good concurrent validity of the MCCB. Furthermore, the MCCB showed high discriminant ability between MDD patients and healthy controls, and a principal component analysis of the MCCB in MDD patients revealed four domains with acceptable internal structure.

LIMITATIONS

We did not consider confounding factors, such as the course, severity of symptoms and medication treatments, which might bias the cognitive assessment. In addition, the use of the MoCA as a reference scale for mild cognitive impairment could weaken the concurrent validity of the MCCB in MDD patients.

CONCLUSION

Our findings demonstrated that the MCCB may be clinically useful as a cognitive impairment rating battery in Chinese patients with MDD.

Defining cognitive and functional profiles in schizophrenia and affective disorders

BACKGROUND

Neurocognitive dysfunction is a common symptom of various major psychiatric disorders, including schizophrenia, major depressive disorder (MDD), and bipolar I disorder (BD). In this study, we investigated whether cognitive profiles and daily skill functioning could effectively differentiate between patients with schizophrenia, MDD, and BD.

METHOD

In this cross-sectional study, we recruited a total of 63 patients with schizophrenia, 55 patients with MDD, 43 patients with BD, and 92 healthy control subjects. We evaluated participants' cognitive functions and functional capacity using the Brief Assessment of Cognition in Schizophrenia (BACS) and the UCSD Performance-based Skills Assessment, Brief Version (UPSA-B), respectively. Multivariate analysis of covariance was then adopted to determine inter-group differences in BACS and UPSA-B performance.

RESULTS

The BACS was capable of differentiating patients with a major psychiatric disorder (schizophrenia, MDD, and BD) from healthy subjects. Furthermore, schizophrenia patients had poorer motor speed performance than patients with affective disorders. The UPSA-B, particularly the financial portion, was able to distinguish schizophrenia patients from other groups. However, we did not observe any differences in UPSA-B performance between patients with mood disorders and the healthy controls. No significant difference between patients with BD and those with MDD were observed in either cognitive function or in functional capacity. The performances of the BACS and the UPSA-B were positively correlated, particularly in the MDD group.

CONCLUSION

Considering overall performance, the BACS and the UPSA-B characterize different endophenotyping profiles in the aforementioned four participant groups. Therefore, the results support the need for comprehensive assessments that target both cognitive function and functional capacity for patients with major psychiatric disorders.

State-Independent Microstructural White Matter Abnormalities in Major Depressive Disorder

BACKGROUND

Even with continuous antidepressant treatment, residual symptoms and the risk of relapse can persist in remitted major depressive disorder (MDD) patients. Hence, having a clear recognition of the persistent abnormalities of the underlying neural substrate in MDD through a longitudinal investigation is of great importance.

METHODS

A total of 127 adult medication-free MDD patients with an acute depressive episode and 118 matched healthy controls (HCs) underwent diffusion tensor imaging. Over a 6-month treatment course, 62 remitted patients underwent a second scan. Remission was defined as a 24-item Hamilton Depression Rating Scale (HAMD₂₄) score ≤7 for at least two weeks. Diffusion tensor imaging was performed with a 3.0 T scanner. Differences in whole-brain fractional anisotropy (FA) between MDD patients and HCs were assessed by an independent t-test using gender, age, and education as covariates.

RESULTS

Significant FA reductions in the left insula, left middle occipital gyrus, right thalamus, left pallidum and left precuneus were observed in current MDD (cMDD) patients compared with HCs. Moreover, significant FA reductions in the left insula were observed in remitted (rMDD) patients compared to HCs. However, no significant differences in FA values were found when comparing cMDD and rMDD patients.

CONCLUSIONS

The abnormalities in the insula showed state-independent characteristics, while the abnormalities in the middle occipital gyrus, thalamus, pallidum and precuneus seemed to be state-dependent impairments in MDD patients.

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.

Neurobiological commonalities and distinctions among 3 major psychiatric disorders: a graph theoretical analysis of the structural connectome

BACKGROUND

White matter network alterations have increasingly been implicated in major depressive disorder, bipolar disorder and schizophrenia. The aim of this study was to identify shared and distinct white matter network alterations among the 3 disorders.

METHODS

We used analysis of covariance, with age and gender as covariates, to investigate white matter network alterations in 123 patients with schizophrenia, 123 with bipolar disorder, 124 with major depressive disorder and 209 healthy controls.

RESULTS

We found significant group differences in global network efficiency (F = 3.386, p = 0.018), nodal efficiency (F = 8.015, p < 0.001 corrected for false discovery rate [FDR]) and nodal degree (F = 5.971, pFDR < 0.001) in the left middle occipital gyrus, as well as nodal efficiency (F = 6.930, pFDR < 0.001) and nodal degree (F = 5.884, pFDR < 0.001) in the left postcentral gyrus. We found no significant alterations in patients with major depressive disorder. Post hoc analyses revealed that compared with healthy controls, patients in the schizophrenia and bipolar disorder groups showed decreased global network efficiency, nodal efficiency and nodal degree in the left middle occipital gyrus. Furthermore, patients in the schizophrenia group showed decreased nodal efficiency and nodal degree in the left postcentral gyrus compared with healthy controls.

LIMITATIONS

Our findings could have been confounded in part by treatment differences.

CONCLUSION

Our findings implicate graded white matter network alterations across the 3 disorders, enhancing our understanding of shared and distinct pathophysiological mechanisms across diagnoses and providing vital insights into neuroimaging-based methods for diagnosis and research.

Combined Measures of Psychomotor and Cognitive Alterations as a Potential Hallmark for Bipolar Depression

OBJECTIVE

The current study aimed to examine whether specific features of psychomotor retardation (PMR) and cognitive functioning established different profiles in unipolar (UD) and bipolar depression (BD).

METHODS

Two groups of age-matched patients with UD (n=54) and BD (n=20) completed the Montgomery-Asberg Depression Rating Scale (MADRS/60), the Montreal Cognitive Assessment (MoCA/30), and the Salpêtrière Retardation Rating Scale (SRRS/60). We analyzed the group effect and then performed intra-group analyses.

RESULTS

The BD patients have higher SRRS score, and lower MoCA score than UD despite no difference on the level of depression between UD and BD. Our results show that PMR can be predicted by the level of depression in UD and by the cognitive alteration and onset of disease in BD.

CONCLUSION

PMR is a relevant marker of depression. Our results highlight the importance of concomitant evaluation of psychomotor and cognitive functions in the distinction of UD and BD symptoms.

Cognitive function following a major depressive episode: a systematic review and meta-analysis

BACKGROUND

Substantial evidence suggests that cognitive deficits might persist after remission of a major depressive episode. However, results are inconsistent relative to the importance, pattern, severity, and moderating factors of this impairment. We aimed to determine how cognitive function following a major depressive episode compares with normal function, to specify the pattern and severity of persistent cognitive dysfunctions, and to examine the potential moderator effect of ten prespecified clinical and demographic variables.

METHODS

We did a systematic review and meta-analysis of the published research. We searched systematically MEDLINE, Embase, PsycARTICLES, PsycINFO, the Cochrane Library, and relevant reviews identified by our database search, for research published from Jan 1, 1972, up to Jan 31, 2018, for studies of patients with past depression. We included all independent studies of patients who were assessed while in remission from a major depressive episode with at least one cognitive test, with inclusion of a healthy control group assessed with either the same test(s) as the major depressive episode group or with a standardised test with published age-stratified normative data. The main outcome was the difference in cognitive performance between major depressive episode remitters and healthy controls. Effect sizes were calculated using random-effects models for cognitive outcomes classified into 18 standard domains. Moderators of between-study variability were assessed using mixed-effects subgroup analyses and meta-regressions.

FINDINGS

Of 10 126 citations identified by our search, 75 cognitive variables from 252 eligible studies (11 882 major depressive episode remitters and 8533 healthy controls) were included in our meta-analysis. Significant deficits following major depressive episode remission were observed in 55 (73%) of the 75 cognitive variables. These deficits (in the domains of processing speed, visual selective attention, working memory, verbal learning, and executive functioning), were generally small (30 [40%] of the 75 variables) or medium (22 [29%]) in size, although three long-term memory variables showed large deficits: g=-0·81 [95% CI -1·01 to -0·61] for logical memory immediate recall, g=-0·88 [-1·19 to -0·57] for logical memory delayed recall, and g=-0·84 [-1·18 to -0·50] for Cambridge Neuropsychological Test Automated Battery pattern recognition latency. Auditory attention, general autobiographical memory, inhibition ability unconstrained by speed, and intellectual functioning unconstrained by speed were equivalent between major depressive episode remitters and matched controls. The number of previous depressive episodes explained heterogeneity in the majority of variables (z=-2·06 [p=0·039] to z=-4·26 [p<0·0001]).

INTERPRETATION

Deficits in selective attention, working memory, and long-term memory persist in remission from a major depressive episode and worsen with repeated episodes. Depression treatments, including relapse prevention, need to target these cognitive functions to optimise prognosis.

FUNDING

None.

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.

Cognitive abilities underlying performance on the modified card sorting test: novel and traditional scores

The Modified Card Sorting Test (MCST) is a widely used variation of the Wisconsin Card Sorting Test. It is faster to administer, less frustrating for respondents and less ambiguous in its scoring but has been criticized for its task impurity and low discriminability between control participants and clinical groups prone to executive dysfunction. This study aimed to examine the executive functions (EF) underlying traditional (number of categories completed, perseverative errors) and novel scores for the MCST, and compare their ability to differentiate between control and clinical samples. Novel and traditional MCST scores were compared between 94 control participants, 87 with bipolar disorder and 64 with major depression. The relationship between MCST scores and traditional EF tasks was examined through correlation and regression analyses. All MCST scores were associated with at least one measure of EF, the most common of which were the Trail Making or Hayling Tests. IQ predicted most scores on the MCST, save for nonperseverative errors and categorizing efficiency. Traditional and novel scores differentiated between clinical and control groups. These findings support the utility of the MCST in detecting executive dysfunction and highlight the importance of new scoring methods in increasing the specificity and interpretability of this task.

Cognitive profiles in major depressive disorder: Comparing remitters and non-remitters to rTMS treatment

Major Depressive Disorder (MDD) is typically accompanied by cognitive impairment. Repetitive Transcranial Magnetic Stimulation (rTMS) treatment for MDD involves stimulation of the dorsolateral prefrontal cortex which plays an important role in cognition. This study aimed to identify differences in cognitive profiles between remitters and non-remitters to rTMS at baseline and across treatment. 25 patients with MDD performed cognitive tasks at baseline and after 6, 12 and 30 sessions of rTMS. At baseline, there was no difference in simple reaction time (RT) between groups, but remitters (n = 13) showed faster RTs than non-remitters (n = 12) in the Switch and No-Switch conditions of Task Switching. Across sessions, remitters showed a decrease in 3-Back omission errors and RTs to 3-Back, Stroop's Congruent and Incongruent, and Task Switching's Switch and No-Switch conditions, whereas non-remitters only showed improvements in Stroop Congruent and Incongruent RTs. Baseline and final scores on the Hamilton Depression Rating Scale were positively correlated with Switch and No-Switch RTs. This study demonstrates that eventual remitters to rTMS treatment for MDD perform better in cognitive tasks requiring shifting attention, and this difference is observable prior to the start of treatment. Remitters also show improvement in both their mood and cognitive performance.