When euthymia is just not good enough: the neuropsychology of bipolar disorder

Inhibitory control in Bipolar Disorder disclosed by theta band modulation

BACKGROUND

Cognitive inhibition is key to cognitive control in healthy and psychiatric conditions. Bipolar Disorder (BD) individuals display a range of inhibitory deficits and high levels of impulsivity across all stages of the disease, including euthymia.

METHODS

We tested how the inhibition of heuristics in favor of analytical strategies influences the elaboration of sentences with logical quantifiers by means of a sentence-picture matching task in which the processing of quantified sentences containing the logical universal and particular quantifiers was required. Behavioral and brain oscillatory responses were assessed employing EEG recordings.

RESULTS

In Experiment 1, in a group of healthy volunteers, we demonstrated how the presence of a universal quantifier generates an inhibition, characterized by a high cognitive load, which is resolved at the expense of a poorer behavioral performance compared to a lower cognitive load and neutral control task. In Experiment 2, comparing healthy adults and BD patients, EEG time-frequency analysis showed a different modulation of the theta frequency band localized centrally in the medial frontal areas and representative of the different degrees of cognitive control between groups.

LIMITATIONS

Electrophysiological description should be interpreted with caution in light of the high signal-to-noise ratio determined by the complexity of the task.

CONCLUSIONS

Even in euthymia, BD limited availability of resources for cognitive inhibition impacts the functionality of a fronto-parietal cortical network, responsible for cognitive control, and orchestrated by the activity of frontal areas synchronized in theta and beta frequency.

Altered intrinsic brain activity and cognitive impairment in euthymic, unmedicated individuals with bipolar disorder

Cognitive impairment in euthymic bipolar disorder (BD) contributes to poor functional outcomes. Resting-state magnetic resonance imaging (MRI)may help us understand the neurobiology of cognitive impairment in BD. Here, forty unmedicated euthymic BD patients and thirty-nine healthy controls were recruited, undergoing MRI scans and neuropsychological measures. The amplitude of low-frequency fluctuation (ALFF) and ALFF-based functional connectivity (FC) analysis was employed to explore the potential alterations of neural activity. Voxel-wised correlation was calculated between clinical and cognitive variables and abnormal brain activity. Compared with healthy controls, euthymic BD patients showed worse cognitive performance in Trail Making Test, Digit Span Test, and Stroop Color-Word Test (SCWT). The euthymic BD group had significantly lower ALFF in the left medial frontal gyrus, right middle frontal gyrus, right postcentral gyrus, and left superior frontal gyrus. Furthermore, we found decreased ALFF values in the right middle frontal gyrus that was negatively correlated with cognitive inhibition, (r = -0.43, P = 0.015). ALFF-based FC analysis showed that BD group showed significantly decreased FC between the right middle frontal gyrus (seed) and left middle temporal gyrus and left medial frontal gyrus, (Two-tailed, PFWE < 0.05, TFCE corrected). The findings demonstrated that individuals with BD during the euthymic phase exhibited decreased ALFF and hypoconnectivity of key brain areas within the frontoparietal network. These altered spontaneous brain activity in euthymic BD patients may be involved in the pathophysiology mechanism of cognitive deficits.

Time-Frequency Characterization of Resting Brain in Bipolar Disorder during Euthymia-A Preliminary Study

The goal of this paper is to investigate the baseline brain activity in euthymic bipolar disorder (BD) patients by comparing it to healthy controls (HC) with the use of a variety of resting state functional magnetic resonance imaging (rs-fMRI) analyses, such as amplitude of low frequency fluctuations (ALFF), fractional ALFF (f/ALFF), ALFF-based functional connectivity (FC), and r egional homogeneity (ReHo). We hypothesize that above-mentioned techniques will differentiate BD from HC indicating dissimilarities between the groups within different brain structures. Forty-two participants divided into two groups of euthymic BD patients (n = 21) and HC (n = 21) underwent rs-fMRI evaluation. Typical band ALFF, slow-4, slow-5, f/ALFF, as well as ReHo indexes were analyzed. Regions with altered ALFF were chosen as ROI for seed-to-voxel analysis of FC. As opposed to HC, BD patients revealed: increased ALFF in left insula; increased slow-5 in left middle temporal pole; increased f/ALFF in left superior frontal gyrus, left superior temporal gyrus, left middle occipital gyrus, right putamen, and bilateral thalamus. There were no significant differences between BD and HC groups in slow-4 band. Compared to HC, the BD group presented higher ReHo values in the left superior medial frontal gyrus and lower ReHo values in the right supplementary motor area. FC analysis revealed significant hyper-connectivity within the BD group between left insula and bilateral middle frontal gyrus, right superior parietal gyrus, right supramarginal gyrus, left inferior parietal gyrus, left cerebellum, and left supplementary motor area. To our best knowledge, this is the first rs-fMRI study combining ReHo, ALFF, f/ALFF, and subdivided frequency bands (slow-4 and slow-5) in euthymic BD patients. ALFF, f/ALFF, slow-5, as well as REHO analysis revealed significant differences between two studied groups. Although results obtained with the above methods enable to identify group-specific brain structures, no overlap between the brain regions was detected. This indicates that combination of foregoing rs-fMRI methods may complement each other, revealing the bigger picture of the complex resting state abnormalities in BD.

The Impact of Lithium on Brain Function in Bipolar Disorder: An Updated Review of Functional Magnetic Resonance Imaging Studies

Lithium remains a gold standard treatment for bipolar disorder (BD), and functional magnetic resonance imaging (fMRI) studies have contributed to clarifying its impact on neural circuitries in affected individuals. However, the specific neurobiological mechanisms through which lithium exerts its effects on brain function are not fully understood. In this review, we aimed to summarize the results of recent fMRI studies evaluating the impact of lithium on brain functional activity and connectivity in patients diagnosed with BD. We performed a literature search of available sources found in the PubMed database reported in English since 2016, when the last available review on this topic was published. Five fMRI studies in resting-state condition and six studies performed during the execution of emotional tasks met the inclusion criteria. Overall, the available evidence supports normalizing effects of lithium on brain activity and connectivity. Most of these studies reported a normalization in prefrontal regions and interconnected areas involved in emotion regulation and processing, regardless of the task employed. Importantly, lithium treatment showed distinct patterns of activity/connectivity changes compared with other treatments. Finally, lithium modulation of neural circuitries was found to be associated with clinical improvement in BD. These results are consistent with the hypothesis that selective abnormalities in neural circuitries supporting emotion processing and regulation improve during lithium treatment in BD. However, the heterogeneity of the examined studies regarding study design, sample selection, and analysis methods might limit the generalizability of the findings and lead to difficulties in comparing the results. Therefore, in future studies, larger cohorts and homogeneous experimental tasks are needed to further corroborate these findings.

A qualitative exploration of how people with bipolar disorder consider risk-taking in everyday decisions

BACKGROUND

Difficulties with decision making and risk taking in individuals with bipolar disorder (BD) have been associated with mood episodes. However, there is limited information about these experiences during euthymia, the mood state where people with BD spent the majority of their time.

AIMS

To examine how individuals with BD consider risk in everyday decisions during their euthymic phase.

METHOD

We conducted a qualitative study that used semi-structured audio recorded interviews. Eight euthymic participants with confirmed BD were interviewed, and we used interpretative phenomenological analysis to analyse the data.

RESULTS

We identified four themes. The first theme, 'Who I really am', involves the relationship between individual identity and risks taken. The second theme, 'Taking back control of my life', explored the relationship between risks taken as participants strove to keep control of their lives. The third theme, 'Fear of the "what ifs"', represents how the fear of negative consequences from taking risks impacts risk decisions. Finally, the fourth theme, 'The role of family and friends', highlights the important role that a supporting network can play in their lives in the context of taking risks.

CONCLUSIONS

The study highlights aspects that can impact on an individual with BD's consideration of risk during euthymia. Identity, control, fear and support all play a role when a person considers risk in their decision-making process, and they should be taken into consideration when exploring risk with individuals with BD in clinical settings, and inform the design of future interventions.

Dissociative Experience in Unipolar and Bipolar Depression: Exploring the Great Divide

Objective

Unipolar and bipolar depression (UD and BD) differ strikingly in respect to neurobiology, course and management, but their apparent clinical similarity often leads to misdiagnosis resulting in chronicity of course and treatment failure. In this study we have tried to assess whether UD and BD can be differentiated on the basis of their dissociative symptoms.

Methods

Thrty-six UD patients and 35 BD patients in active episodes, without any psychiatric comorbidity were selected from outpatient department and compared for depressive and dissociative symptoms using Hamilton Depression Rating Scale and Dissociative Experience Scale-II (DES-II).

Results

We found that thought the two groups didn’t differ in terms of the socio-demographic or clinical variables, BD group had significantly higher dissociative experience (U=343, p=0.001) than UD and the difference remained significant even after adjusting for the confounding factors.

Conclusion

Our study shows that dissociative symptoms are significantly more prevalent in the depressive episodes of bipolar affective disorder as compared to the UD and can be an important tool in differentiating between the two disorders with very similar clinical profile. The difference can be measured using a simple self-report questionnaire like DES-II.

Resting-state functional connectivity in individuals with bipolar disorder during clinical remission: a systematic review

BACKGROUND

Bipolar disorder is chronic and debilitating. Studies investigating resting-state functional connectivity in individuals with bipolar disorder may help to inform neurobiological models of illness.

METHODS

We conducted a systematic review with the following goals: to summarize the literature on resting-state functional connectivity in bipolar disorder during clinical remission (euthymia) compared with healthy controls; to critically appraise the literature and research gaps; and to propose directions for future research. We searched PubMed/MEDLINE, Embase, PsycINFO, CINAHL and grey literature up to April 2017.

RESULTS

Twenty-three studies were included. The most consistent finding was the absence of differences in resting-state functional connectivity of the default mode network (DMN), frontoparietal network (FPN) and salience network (SN) between people with bipolar disorder and controls, using independent component analysis. However, 2 studies in people with bipolar disorder who were positive for psychosis history reported DMN hypoconnectivity. Studies using seed-based analysis largely reported aberrant resting-state functional connectivity with the amygdala, ventrolateral prefrontal cortex, cingulate cortex and medial prefrontal cortex in people with bipolar disorder compared with controls. Few studies used regional homogeneity or amplitude of low-frequency fluctuations.

LIMITATIONS

We found heterogeneity in the analysis methods used.

CONCLUSION

Stability of the DMN, FPN and SN may reflect a state of remission. Further, DMN hypoconnectivity may reflect a positive history of psychosis in patients with bipolar disorder compared with controls, highlighting a potentially different neural phenotype of psychosis in people with bipolar disorder. Resting-state functional connectivity changes between the amygdala, prefrontal cortex and cingulate cortex may reflect a neural correlate of subthreshold symptoms experienced in bipolar disorder euthymia, the trait-based pathophysiology of bipolar disorder and/or a compensatory mechanism to maintain a state of euthymia.

Resting state functional connectivity in women with bipolar disorder during clinical remission

OBJECTIVES

Periods of euthymia in bipolar disorder (BD) serve as a valuable time to study trait-based pathophysiology. The use of resting state functional connectivity (Rs-FC) can aid in the understanding of BD pathophysiology free of task or mood state biases. The present study investigated two unexplored areas of Rs-FC research in bipolar remission: (i) Rs-FC in women, controlling for the potential influence of premenstrual symptoms, and (ii) the use of both independent component analysis (ICA) and seed-based analysis (SBA) to investigate Rs-FC.

METHODS

We investigated Rs-FC of the default mode network, meso-paralimbic network and fronto-parietal network in a sample of 32 euthymic women with BD and 36 age-matched controls during the mid-follicular phase of their menstrual cycle. Rs-FC was assessed with ICA and SBA using the posterior cingulate cortex (PCC), amygdala and dorsolateral prefrontal cortex (dlPFC) as seed points for their respective resting state networks.

RESULTS

In BD, compared to controls, SBAs revealed increased coupling between the PCC and the angular gyrus (P=.002, false discovery rate [FDR]-corrected) and between the right dlPFC and the brainstem (P=.03, FDR-corrected). In BD only, PCC-angular gyrus coupling was correlated with anxiety symptoms. Group differences in Rs-FC using ICA did not survive multiple comparisons.

CONCLUSIONS

Negative findings from whole-brain ICA Rs-FC may reflect a state of clinical remission in BD. Heightened activation between the PCC and the angular gyrus and between the dlPFC and the brainstem may reflect (i) an abnormal trait integration of affective information during clinical remission and/or (ii) an adaptive compensatory mechanism required for clinical stabilization.

A meta-analysis of neuropsychological functioning in first-episode bipolar disorders

Broad neuropsychological deficits have been consistently demonstrated in well-established bipolar disorder. The aim of the current study was to systematically review neuropsychological studies in first-episode bipolar disorders to determine the breadth, extent and predictors of cognitive dysfunction at this early stage of illness through meta-analytic procedures. Electronic databases were searched for studies published between January 1980 and December 2013. Twelve studies met eligibility criteria (N = 341, mean age = 28.2 years), and pooled effect sizes (ES) were calculated across eight cognitive domains. Moderator analyses were conducted to identify predictors of between-study heterogeneity. Controlling for known confounds, medium to large deficits (ES ≥ 0.5) in psychomotor speed, attention and working memory, and cognitive flexibility were identified, whereas smaller deficits (ES 0.20-0.49) were found in the domains of verbal learning and memory, attentional switching, and verbal fluency. A medium to large deficit in response inhibition was only detected in non-euthymic cases. Visual learning and memory functioning was not significantly worse in cases compared with controls. Overall, first-episode bipolar disorders are associated with widespread cognitive dysfunction. Since euthymia was not associated with superior cognitive performance in most domains, these results indicate that even in the earliest stages of disease, cognitive deficits are not mood-state dependent. The current findings have important implications for whether cognitive impairments represent neurodevelopmental or neurodegenerative processes. Future studies need to more clearly characterise the presence of psychotic features, and the nature and number of previous mood episodes.

The impact of alcohol and tobacco use on in vivo glutathione in youth with bipolar disorder: an exploratory study

Risky alcohol consumption and tobacco smoking is highly prevalent in bipolar disorder (BD) and is associated with increased formation of neural reactive oxygen species. Proton magnetic resonance spectroscopy ((1)H-MRS) is an in vivo imaging modality that allows quantification of glutathione (GSH) concentration, the brains primary antioxidant. Sixty-four patients with BD and 49 controls (18-30 years) completed self-report questionnaires regarding alcohol and tobacco use and underwent (1)H-MRS. Levels of GSH in the hippocampus and anterior cingulate cortex (ACC) were determined. Within-group Pearson's correlations were used to explore the relationship between alcohol use and GSH concentration for BD and controls, covarying for age, gender, family history of alcohol dependence and smoking status. Relationships between GSH and presence/severity of alcohol-induced blackouts were determined using Spearman's correlations. In BD, reduced hippocampal-GSH associated with higher alcohol use (R = -0.489, p < 0.021). Reduction of ACC-GSH with increased drinking was non-significant when controlling for tobacco use. Independent samples t-test revealed a significantly decreased ACC-GSH in smokers with BD (t (53) = 4.162, p < 0.001). In controls, alcohol use was not correlated to GSH in either region. In both patients and controls, reduced hippocampal-GSH was associated with blackout presence/severity, supporting a role for the hippocampus in the continuum of alcohol-induced memory impairments. Our preliminary findings suggest that in youth with BD reduced hippocampal-GSH is associated with risky alcohol use and alcohol and tobacco use is associated with reduced ACC-GSH, highlighting the role of these substances as modifiable risk factors for decreased anti-oxidant capacity in BD.

Cognitive compromise in bipolar disorder with chronic cannabis use: cause or consequence?

This article briefly reviews the neuropsychological deficits associated with bipolar disorder and examines how substance abuse, in particular chronic cannabis use, may contribute to these. The focus of the article is cannabis, owing to its popularity in patients with bipolar disorder, although many studies focus on its use in conjunction with other substances. The findings are contextualized within bipolar disorder, examining functional outcome.

Overgenerality memory style for past and future events and emotions related in bipolar disorder. What are the links with problem solving and interpersonal relationships?

This study investigated patients with Bipolar Disorder's abilities to generate specific past and future events in response to positive and negative cues words as well as emotional intensity related to these ones. The relationships between the number of generated specific events cognitive functioning, interpersonal problems and the ability to problem solving were investigated. Nineteen BD and nineteen healthy controls completed a French version of the AMT to evaluate the past and future events recall, in function of their valence, and emotions related. Furthermore, they completed the Optional Thinking Test, the Inventory of Interpersonal Problems and the neuropsychological measures. Compared to healthy controls, BD recollected (1) fewer specific past negative events and (2) fewer future specific positive and negative events furthermore, (3) they felt more emotional intensity related to future events. These results were explained in the light of theoretical models. Finally, specific past memories deficits in BD were linked with issues in problem solving but not with levels of distress arising from interpersonal problems. In view of AM functions in everyday life, all types of deficits should be taken into consideration, and AM remediation envisaged.

Pattern of heat shock factor and heat shock protein expression in lymphocytes of bipolar patients: increased HSP70-glucocorticoid receptor heterocomplex

Bipolar disorder (BD), a stress-related disease, is characterized by altered glucocorticoid receptor (GR) signalling. Stress response includes activation of heat shock factor (HSF) and subsequent heat shock protein (HSP) synthesis which regulate GR folding and function. The objective of this study was to investigate the possible role of HSFs, HSPs and their interaction with GR in BD. We applied immunoprecipitation, SDS-PAGE/Western blot analysis and electrophoretic mobility shift assay (EMSA) in lymphocytes (whole cell or nuclear extracts) from BD patients and healthy subjects and determined the HSPs (HSP90 and HSP70), the heterocomplexes HSP90-GR and HSP70-GR, the HSFs (HSF1 and HSF4) as well as the HSF-DNA binding. The HSP70-GR heterocomplex was elevated (p < 0.05) in BD patients vs healthy subjects, and nuclear HSP70 was reduced (p ≤ 0.01) in bipolar manic patients. Protein levels of HSF1, HSF4, HSP90, HSP90-GR heterocomplex, and HSF-DNA binding remained unaltered in BD patients vs healthy subjects. The corresponding effect sizes (ES) indicated a large ES for HSP70-GR, HSP70, HSF-DNA binding and HSF4, and a medium ES for HSP90, HSF1 and HSP90-GR between healthy subjects and bipolar patients. Significant correlations among HSFs, HSPs, GR and HSP70-GR heterocomplex were observed in healthy subjects, which were abrogated in bipolar patients. The higher interaction between GR and HSP70 and the disturbances in the relations among heat shock response parameters and GR as observed in our BD patients may provide novel insights into the contribution of these factors in BD aetiopathogenesis.

A systematic review and meta-analysis of proton magnetic resonance spectroscopy and mismatch negativity in bipolar disorder

Aberrant glutamate neurotransmission has been implicated in the pathophysiology of bipolar disorder with accumulating evidence from imaging, post-mortem and pathology studies. Studies investigating in vivo changes to the glutamatergic system have not been as consistent and warrant clarification. Studies utilizing proton-magnetic resonance spectroscopy ((1)H-MRS) have reported increased levels of combined glutamate and glutamine ("Glx"), which have been linked to impairments in N-methyl-d-aspartate (NMDA) receptor function. Similarly, neurophysiological studies utilising mismatch negativity (MMN) as an index of NMDA receptor function, have reported impairments in bipolar disorder. Here, we provide a systematic review of the literature in regards to the concentration of Glx and the magnitude of MMN in bipolar disorder. Separate meta-analyses revealed that bipolar disorder was associated with increased Glx concentration and decreased MMN-both measured frontally. The current findings corroborate previous evidence indicating that bipolar disorder is characterized by a perturbed frontal glutamate system. These observed changes in bipolar disorder might manifest as impairments in neuronal-glial interactions that lead to disrupted neuronal output and ultimately result in the characteristic neurocognitive sequelae associated with this disorder.

Reduced regulatory T cells are associated with higher levels of Th1/TH17 cytokines and activated MAPK in type 1 bipolar disorder

Bipolar disorder (BD) has been associated with an immunologic imbalance shown by increased peripheral inflammatory markers. The underlying mechanisms of this phenomenon may include changes in circulating cells and differential activation of mitogen-activated protein kinases (MAPKs). Twenty-seven euthymic female subjects with BD type I (all medicated) and 24 age- and sex-matched controls were recruited in this study. Lymphocytes were isolated and stimulated in vitro to assess Th1/Th17/Th2 cytokines (IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ and TNF-α) and MAPK phosphorylation. The expression of phospho-MAPKs, a large panel of lymphocyte subsets and cytokines were assessed by multi-color flow cytometry. BD patients had reduced proportions of natural T regulatory cells (CD4+ CD25+ FoxP3+) (p<0.01) in parallel to higher cytokine production (all p<0.01) than healthy controls. In particular, BD was associated with a strong bias to Th1 rather than Th2 profile. There was an expansion of senescence-associated cells (CD8+ CD28-) in BD (p<0.0001). T cells of BD patients had an increased p-ERK signaling (p<0.0001), indicating lymphocyte activation. Our data suggest that multiple molecular and cellular mechanisms may contribute to the immunologic imbalance observed in BD. In addition, our data concur to an early senescence process in these patients.

Microstructural white matter changes in the corpus callosum of young people with Bipolar Disorder: a diffusion tensor imaging study

To date, most studies of white matter changes in Bipolar Disorder (BD) have been conducted in older subjects and with well-established disorders. Studies of young people who are closer to their illness onset may help to identify core neurobiological characteristics and separate these from consequences of repeated illness episodes or prolonged treatment. Diffusion tensor imaging (DTI) was used to examine white matter microstructural changes in 58 young patients with BD (mean age 23 years; range 16-30 years) and 40 controls. Whole brain voxelwise measures of fractional anisotropy (FA), parallel diffusivity (λ//) and radial diffusivity (λ⊥) were calculated for all subjects. White matter microstructure differences (decreased FA corrected p<.05) were found between the patients with BD and controls in the genu, body and splenium of the corpus callosum as well as the superior and anterior corona radiata. In addition, significantly increased radial diffusivity (p<.01) was found in the BD group. Neuroimaging studies of young patients with BD may help to clarify neurodevelopmental aspects of the illness and for identifying biomarkers of disease onset and progression. Our findings provide evidence of microstructural white matter changes early in the course of illness within the corpus callosum and the nature of these changes suggest they are associated with abnormalities in the myelination of axons.

Distinguishing young people with emerging bipolar disorders from those with unipolar depression

BACKGROUND

To facilitate early intervention, there is a need to distinguish unipolar versus bipolar illness trajectories in adolescents and young adults with adult-type mood disorders.

METHODS

Detailed clinical and neuropsychological evaluation of 308 young persons (aged 12 to 30 years) with moderately severe unipolar and bipolar affective disorders.

RESULTS

Almost 30% (90/308) of young people (mean age=19.4±4.4yr) presenting for care with affective disorders met criteria for a bipolar-type syndrome (26% with bipolar I). Subjects with bipolar- and unipolar-type syndromes were of similar age (19.8 vs. 19.2yr) and reported comparable ages of onset (14.5 vs. 14.3yr). Clinically, those subjects with unipolar and bipolar-type disorders reported similar levels of psychological distress, depressive symptoms, current role impairment, neuropsychological dysfunction and alcohol or other substance misuse. Subjects with unipolar disorders reported more social anxiety (p<0.01). Subjects with bipolar disorders were more likely to report a family history of bipolar (21% vs. 11%; [χ(2)=4.0, p<.05]) or psychotic (19% vs. 9%; [χ(2)=5.5, p<.05]), or substance misuse (35% vs. 23%; [χ(2)=3.9, p<.05]), but not depressive (48% vs. 53%; χ(2)=0.3, p=.582]) disorders.

CONCLUSIONS

Young subjects with bipolar disorders were best discriminated by a family history of bipolar, psychotic or substance use disorders. Early in the course of illness, clinical features of depression, or neuropsychological function, do not readily differentiate the two illness trajectories.

Neuropsychological performance in euthymic Indian patients with bipolar disorder type I: correlation between quality of life and global functioning

AIM

This study aims to assess the neuropsychological performance, quality of life (QoL) and global functioning in euthymic patients and healthy controls. It also explores the hypothesis that poorer cognitive performance will adversely influence the QoL of patients with bipolar disorder.

METHODS

We carried out a cross-sectional assessment of 30 euthymic patients with bipolar disorder type I and compared them to a healthy control group. All the participants were evaluated for IQ, sustained attention, information processing speed, executive functions and memory using the Verbal Adult Intelligence Scale, the Trail Making Test A & B, the Stroop Color and Word Test, the N-Back test and Postgraduate Institute Memory Scale. Patients were also rated on World Health Organization QoL (BREF, Hindi version) and Global Assessment of Functioning.

RESULTS

The patient and control group were comparable in age, sex distribution, education, and verbal IQ. Compared to controls, the patients performed poorly on tests for sustained attention, information processing speed, cognitive flexibility, delayed recall and verbal retention. Patients had significantly lower scores in psychological and social domains of QoL as well as global functioning. The test for sustained attention, executive functions and verbal retention showed a significant correlation to QoL domains. On stepwise multiple regression, cognitive flexibility and set shifting (Trail Making Test Part B) could significantly predict the psychological and social QoL domains, explaining 17% and 32% of the variance, respectively.

CONCLUSION

Patients with bipolar disorder display cognitive impairments in the euthymic period, which appears to adversely affect their QoL and overall functioning.

The clinical implications of cognitive impairment and allostatic load in bipolar disorder

BACKGROUND

Allostatic load (AL) relates to the neural and bodily "wear and tear" that emerge in the context of chronic stress. This paper aims to provide clinicians with a comprehensive overview of the role of AL in patophysiology of bipolar disorder (BD) and its practical implications.

METHODS

PubMed searches were conducted on English-language articles published from 1970 to June 2011 using the search terms allostatic load, oxidative stress, staging, and bipolar disorder cross-referenced with cognitive impairment, comorbidity, mediators, prevention.

RESULTS

Progressive neural and physical dysfunction consequent to mood episodes in BD can be construed as a cumulative state of AL. The concept of AL can help to reconcile cognitive impairment and increased rates of clinical comorbidities that occur over the course of cumulative BD episodes.

CONCLUSIONS

Data on transduction of psychosocial stress into the neurobiology of mood episodes converges to the concept of AL. Mood episodes prevention would not only alleviate emotional suffering, but also arrest the cycle of AL, cognitive decline, physical morbidities and, eventually, related mortality. These objectives can be achieved by focusing on effective prophylaxis from the first stages of the disorder, providing mood-stabilizing agents and standardized psychoeducation and, potentially, addressing cognitive deficits by the means of specific medication and neuropsychological interventions.

Sensitivity to positive and negative feedback in euthymic patients with bipolar I disorder: the last episode makes the difference

OBJECTIVES

It is unclear whether abnormalities in cognition and motivation, such as altered feedback processing, observed during euthymia represent trait markers of bipolar I disorder (BD-I) or scars from previous episodes that also occur in major depression (MD). The present research examines how previous episodes influence sensitivity to positive and negative feedback, applying multiple hierarchical regression analysis with number of past depressive and manic episodes, residual mood symptoms, affective quality of the last episode, time in remission, medication, illness severity, and age as predictors.

METHODS

The study included 23 euthymic patients with BD-I, 19 remitted patients with MD, and 19 healthy persons who underwent a task which discriminates whether persons learn better from negative or positive feedback.

RESULTS

For both models, predicting sensitivity to positive [F((5,60)) = 6.50, p = 0.001, adjusted R(2) = 0.22] and negative feedback [F((5,60)) = 5.12, p = 0.001, adjusted R(2) = 0.22], the quality of the last affective episode was the only significant predictor. BD-I patients who last experienced a manic episode learned well from positive but not negative feedback, whereas BD-I patients who last experienced a depressive episode showed the opposite pattern.

CONCLUSIONS

Our data identify differences in response to positive and negative consequences carrying over into the euthymic state that are qualitatively related to the polarity of the preceding episode, whereas other disease-related variables had no significant influence. This sheds new light on previous inconsistent data in euthymic BD-I patients and could also guide tailored treatment.

Normal amygdala activation but deficient ventrolateral prefrontal activation in adults with bipolar disorder during euthymia

Functional neuroimaging studies have implicated the involvement of the amygdala and ventrolateral prefrontal cortex (vlPFC) in the pathophysiology of bipolar disorder. Hyperactivity in the amygdala and hypoactivity in the vlPFC have been reported in manic bipolar patients scanned during the performance of an affective faces task. Whether this pattern of dysfunction persists during euthymia is unclear. Using functional magnetic resonance imaging (fMRI), 24 euthymic bipolar and 26 demographically matched healthy control subjects were scanned while performing an affective task paradigm involving the matching and labeling of emotional facial expressions. Neuroimaging results showed that, while amygdala activation did not differ significantly between groups, euthymic patients showed a significant decrease in activation of the right vlPFC (BA47) compared to healthy controls during emotion labeling. Additionally, significant decreases in activation of the right insula, putamen, thalamus and lingual gyrus were observed in euthymic bipolar relative to healthy control subjects during the emotion labeling condition. These data, taken in context with prior studies of bipolar mania using the same emotion recognition task, could suggest that amygdala dysfunction may be a state-related abnormality in bipolar disorder, whereas vlPFC dysfunction may represent a trait-related abnormality of the illness. Characterizing these patterns of activation is likely to help in understanding the neural changes related to the different mood states in bipolar disorder, as well as changes that represent more sustained abnormalities. Future studies that assess mood-state related changes in brain activation in longitudinal bipolar samples would be of interest.

Symptoms and behaviors prior to the first major affective episode of bipolar II disorder. An exploratory study

BACKGROUND

Few studies have investigated the initial prodrome of bipolar disorders, and none has explicitly addressed bipolar II disorder (BD-II). We explored symptoms and behaviors preceding the first major affective episode (FMAE) of BD-II to generate hypotheses concerning possible clinical targets for early intervention.

METHODS

In-depth interviews of 15 BD-II patients and 22 family informants were carried out. Clinical diagnoses were reassessed. The textual data of transcribed interviews were analyzed utilizing qualitative methodology supplemented by quantitative analyses.

RESULTS

All patients experienced clinically significant symptoms and behaviors at an average of more than a decade before the FMAE. Anxiety and depression-type symptoms were the most common. Two distinct subgroups were identified based on prominent and enduring personal characteristics prior to the FMAE. The individuals in one of the subgroups were described as very well-functioning, whereas the individuals in the other subgroup were characterized by neurocognitive deficits, relatively low academic and social functioning, and pronounced irritability and aggressiveness. Furthermore, it is possible that these individuals experience earlier prodromal symptom onset, earlier FMAEs, and more symptoms than individuals without these characteristics.

LIMITATIONS

This is a retrospective and hypothesis-generating qualitative study. The hypotheses generated need to be tested in future studies.

CONCLUSIONS

Prodromal clinical phenomenology is too nonspecific to predict the occurrence of the FMAE of BD-II. However, identifiable subgroups may exist. We hypothesize that neurocognitive deficits together with pronounced irritability and aggressiveness may constitute a vulnerability marker for a subgroup of individuals who subsequently develop BD-II. This subgroup may be of potential interest for early identification.

Trait and state dependent functional impairments in bipolar disorder

Bipolar disorder (BD) is characterized by abnormalities in emotion processing. Specifically, the processing of affective faces appears to be impaired. This study explored functional abnormalities in the neural network underlying the processing of facial affect in three different mood states (euthymic, depressed, and manic) associated with BD. Functional magnetic resonance imaging (fMRI) data were acquired from 18 healthy controls and 18 euthymic, 12 depressed, and 12 manic BD patients while viewing affective or neutral faces. Compared with controls, BD patients in all mood states showed reduced activation in the bilateral orbitofrontal cortex (OFC), indicating that activation in this region is independent of mood state. Activation in the amygdala, dorsolateral prefrontal cortex (DLPFC), and right temporal pole depended on mood state. Whereas activation levels of depressed patients were not significantly different from those of controls, activation levels in both euthymic and manic patients were significantly reduced compared with activation levels of both controls and depressed patients. However in the right DLPFC euthymic patients showed an increased level of activation compared with manic patients. These results add to the evidence for functional deficits in the affective network in BD patients, of which reduced bilateral OFC activation was found to be the most pronounced deficit across all mood states.

Cognitive functioning in patients with bipolar disorder: association with depressive symptoms and alcohol use

BACKGROUND

Cognitive dysfunction is clearly recognized in bipolar patients, but the degree of impairment varies due to methodological factors as well as heterogeneity in patient populations. The goal of this study was to evaluate cognitive functioning in bipolar patients and to assess its association with depressive symptoms. Post hoc the relationship with lifetime alcohol use disorder was explored.

METHODOLOGY/PRINCIPAL FINDINGS

The study included 110 bipolar patients and 75 healthy controls. Patients with severe depressive symptoms, (hypo)manic symptoms and current severe alcohol use disorder were excluded. Diagnoses were evaluated via the Mini-International Neuropsychiatric Interview. Cognitive functioning was measured in domains of psychomotor speed, speed of information processing, attentional switching, verbal memory, visual memory, executive functioning and an overall mean score. Severity of depression was assessed by the Inventory of Depressive Symptomatology-self rating. Patients were euthymic (n = 46) or with current mild (n = 38) or moderate (n = 26) depressive symptoms. Cognitive impairment was found in 26% (z-score 2 or more above reference control group for at least one domain) of patients, most prominent in executive functioning (effect size; ES 0.49) and speed of information processing (ES 0.47). Depressive symptoms were associated with dysfunction in psychomotor speed (adjusted beta 0.43; R(2) 7%), speed of information processing (adjusted beta 0.36; R(2) 20%), attentional switching (adjusted beta 0.24; R(2) 16%) and the mean score (adjusted beta 0.23; R(2) 24%), but not with verbal and visual memory and executive functioning. Depressive symptoms explained 24% of the variance in the mean z-score of all 6 cognitive domains. Comorbid lifetime alcohol use (n = 21) was not associated with cognitive dysfunction.

CONCLUSIONS/SIGNIFICANCE

Cognitive dysfunction in bipolar disorder is more severe in patients with depressive symptoms, especially regarding speed and attention. Therefore, interpretation of cognitive functioning in patients with depressive symptoms should be cautious. No association was found between cognitive functioning and lifetime comorbid alcohol use disorder.

Phosphorylation status of glucocorticoid receptor, heat shock protein 70, cytochrome c and Bax in lymphocytes of euthymic, depressed and manic bipolar patients

Bipolar disorder (BD), a severe mental illness, has been correlated with alterations in glucocorticoid receptor (GR) signaling. Since it is phosphorylated GR that contributes to receptor function and determines its transcriptional activity, the Ser211 being a biomarker for activated GR in vivo, it is pertinent that we seek to determine the putative role of the total phosphorylation status of GR and site-specific phosphorylation at serine 211 (S211) in BD and their possible association with parameters of apoptosis. In lymphocytes from 48 BD patients under multiple psychotropic therapy and 20 healthy subjects, we measured whole cell GR, total GR phosphorylation, and phosphorylation of GR at serine 211 in nucleus, using immunoprecipitation, phosphospecific antibody and Western-blot analysis. Cytosolic cytochrome c and Bax and whole cell HSP70 were determined by immunoblot analysis. One-way ANOVA statistical analysis was carried out. Total phosphorylated GR was lower (P<0.001) while the GR S211 was higher (P<0.001) in all BD patients as compared to healthy subjects. HSP70 was reduced in euthymic (P<0.05), depressed (P<0.001) and manic (P<0.001) as compared to healthy subjects. Cytochrome c was higher in all-patient groups as compared to healthy subjects, however without reaching statistical significance (P>0.05). Bax levels were lower in the cytosolic fraction of all three BD groups. We provide the first evidence of altered GR phosphorylation joined with signs of apoptosis in lymphocytes of BD patients and suggest that the phosphorylation status of GR may play a role in the pathophysiology of bipolar disorder.

The International Society for Bipolar Disorders (ISBD) Task Force report on the nomenclature of course and outcome in bipolar disorders

OBJECTIVES

Via an international panel of experts, this paper attempts to document, review, interpret, and propose operational definitions used to describe the course of bipolar disorders for worldwide use, and to disseminate consensus opinion, supported by the existing literature, in order to better predict course and treatment outcomes.

METHODS

Under the auspices of the International Society for Bipolar Disorders, a task force was convened to examine, report, discuss, and integrate findings from the scientific literature related to observational and clinical trial studies in order to reach consensus and propose terminology describing course and outcome in bipolar disorders.

RESULTS

Consensus opinion was reached regarding the definition of nine terms (response, remission, recovery, relapse, recurrence, subsyndromal states, predominant polarity, switch, and functional outcome) commonly used to describe course and outcomes in bipolar disorders. Further studies are needed to validate the proposed definitions.

CONCLUSION

Determination and dissemination of a consensus nomenclature serve as the first step toward producing a validated and standardized system to define course and outcome in bipolar disorders in order to identify predictors of outcome and effects of treatment. The task force acknowledges that there is limited validity to the proposed terms, as for the most part they represent a consensus opinion. These definitions need to be validated in existing databases and in future studies, and the primary goals of the task force are to stimulate research on the validity of proposed concepts and further standardize the technical nomenclature.

Reduced brain activation in euthymic bipolar patients during response inhibition: an event-related fMRI study

Deficits in inhibitory control have been reported in euthymic bipolar disorder patients. To date, data on the neuroanatomical correlates of these deficits are exclusively related to cognitive inhibition. This study aimed to examine the neural substrates of motor inhibitory control in euthymic bipolar patients. Groups of 20 patients with euthymic bipolar disorder and 20 demographically matched healthy subjects underwent event-related functional magnetic resonance imaging while performing a Go-NoGo task. Between-group differences in brain activation associated with motor response inhibition were assessed by using random-effects analyses. Although euthymic bipolar patients and healthy subjects performed similarly on the Go-NoGo task, they showed different patterns of brain activation associated with response inhibition. Specifically, patients exhibited significantly decreased activation in the left frontopolar cortex and bilateral dorsal amygdala compared with healthy subjects. There were no brain regions that were significantly more activated in patients than in healthy subjects. The findings suggest that euthymic bipolar patients have deficits in their ability to engage the left frontopolar cortex and bilateral dorsal amygdala during response inhibition. Further research should ascertain the role that such deficits may play in the emergence of impulsive behaviors that characterize bipolar disorder.

Reduced insight in bipolar I disorder: neurofunctional and neurostructural correlates: a preliminary study

BACKGROUND

To correlate measures of insight for own psychopathology to structural and functional brain imaging findings in 21 patients with DSM-IV bipolar I disorder.

METHODS

Insight was assessed using the Scale to Assess Unawareness of Mental Disorder (SUMD). Resting single photon emission computed tomography (SPECT) and computed tomography (CT) was conducted in patients and 21 normal comparison subjects matched for age, gender and handedness.

RESULTS

Reduced general insight and symptom awareness, but not symptom attribution, were significantly related to cortical and subcortical atrophy, respectively. No correlations between SPECT and insight measures were identified.

LIMITATIONS

Limited sample size and the use of resting state SPECT.

CONCLUSIONS

General and symptom awareness were related to measures of brain atrophy but not to neurofunctioning as measured by SPECT. Future research should consider the structure and function of specific cortical regions, including the frontal and parietal cortices.

Medicating mood with maintenance in mind: bipolar depression pharmacotherapy

OBJECTIVES

Bipolar depression is a core feature of bipolar disorder, a phase in which many patients spend the majority of time and one that confers a significant degree of burden and risk. The purpose of this paper is to briefly review the evidence base for the pharmacotherapy of bipolar depression and to discuss the recommendations for its optimal management.

METHODS

A detailed literature review was undertaken with a particular emphasis on pharmacological treatment strategies for bipolar depression across the acute and maintenance phases of the illness. Electronic library and Web-based searches were performed using recognised tools (MEDLINE, PubMED, EMBASE and PsychINFO) to identify the pertinent literature. A summary of the evidence base is outlined and then distilled into broad clinical recommendations to guide the pharmacological management of bipolar depression.

RESULTS

Partitioning treatment into acute and maintenance therapy is difficult based on the paucity of current evidence. The evidence from treatment trials favours the use of lithium and lamotrigine as first-line treatment in preference to valproate, and indicates that, for acute episodes, quetiapine and olanzapine have perhaps achieved equivalence at least in terms of efficacy. However, the effectiveness of the atypical antipsychotics in maintenance therapy is constrained by the potential for significant side effects of individual agents and the lack of both long-term research data and clinical experience in treating bipolar disorder as compared to other agents. Conversely, lithium and the anticonvulsants are generally slower to effect symptomatic change, and this limits their usefulness.

CONCLUSIONS

There has been a tendency for research trials of bipolar depression to differentiate the illness cross-sectionally into the acute and maintenance phases of bipolar depression; however, in clinical terms, bipolar depression invariably follows a longitudinal course in which the phases of illness are inextricably linked, and useful acute treatments are typically continued in maintenance. Therefore, when medicating mood in acute bipolar depression it is imperative to keep maintenance in mind as it is this aspect of treatment that determines long-term success.

Conversion (dissociative) symptoms as a presenting feature in early onset bipolar disorder: a case series

We present three cases of early onset bipolar disorder where dissociative (conversion) symptoms preceded the onset of mania. This case series underscores the significance of dissociative/conversion symptoms as an early atypical presentation in juvenile bipolar disorder.

Suicide behavior and neuropsychological assessment of type I bipolar patients

BACKGROUND

Neuropsychological deficits are often described in patients with bipolar disorder (BD). Some symptoms and/or associated characteristics of BD can be more closely associated to those cognitive impairments. We aimed to explore cognitive neuropsychological characteristics of type I bipolar patients (BPI) in terms of lifetime suicide attempt history.

METHOD

We studied 39 BPI outpatients compared with 53 healthy controls (HC) matched by age, educational and intellectual level. All subjects were submitted to a neuropsychological assessment of executive functions, decision-making and declarative episodic memory.

RESULTS

When comparing BDI patients, regardless of suicide attempt history or HC, we observed that bipolar patients performed worse than controls on measures of memory, attention, executive functions and decision-making. Patients with a history of suicide attempt performed worse than non-attempters on measures of decision-making and there were a significant negative correlation between the number of suicide attempts and decision-making results (block 3 and net score). We also found significant positive correlation between the number of suicide attempts and amount of errors in Stroop Color Word Test (part 3).

LIMITATIONS

The sample studied can be considered small and a potentially confounding variable - medication status - were not controlled.

CONCLUSION

Our results show the presence of neuropsychological deficits in memory, executive functions, attention and decision-making in BPI patients. Suicide attempts BPI scored worse than non-suicide attempt BPI on measures of decision-making. More suicide attempts were associated with a worse decision-making process. Future research should explore the relationship between the association between this specific cognitive deficits in BPIs, serotonergic function and suicide behavior in bipolar patients as well other diagnostic groups.

Neuropsychological functioning in euthymic bipolar disorder: a meta-analysis

OBJECTIVE

Although cognitive deficits are prominent in symptomatic patients with bipolar disorder, the extent and pattern of cognitive impairment in euthymic patients remain uncertain.

METHOD

Neuropsychological studies comparing euthymic bipolar patients and healthy controls were evaluated. Across studies, effect sizes reflecting patient-control differences in task performance were computed for the 15 most frequently studied cognitive measures in the literature.

RESULTS

Across the broad cognitive domains of attention/processing speed, episodic memory, and executive functioning, medium-to-large performance effect size differences were consistently observed between patients and controls, favoring the latter. Deficits were not observed on measures of vocabulary and premorbid IQ.

CONCLUSION

Meta-analytic findings provide evidence of a trait-related neuropsychological deficit in bipolar disorder involving attention/processing speed, memory, and executive function. Findings are discussed with regard to potential moderators, etiologic considerations, limitations, and future directions in neuropsychological research on bipolar disorder.

Setting the stage: from prodrome to treatment resistance in bipolar disorder

Bipolar disorder is common, and both difficult to detect and diagnose. Treatment is contingent on clinical needs, which differ according to phase and stage of the illness. A staging model could allow examination of the longitudinal course of the illness and the temporal impact of interventions and events. It could allow for a structured examination of the illness, which could set the stage for algorithms that are tailored to the individuals needs. A staging model could further provide as structure for assessment, gauging treatment and outcomes. The model incorporates prodromal stages and emphasizes early detection and algorithm appropriate intervention where possible. At the other end of the spectrum, the model attempts to operationalize treatment resistance. The utility of the model will need to be validated by empirical research.

Do cognitive deficits in juvenile bipolar disorder persist into adulthood?

This article reviews neuropsychological research in adults with bipolar disorder and compares the findings with emergent data on neuropsychological function in juvenile bipolar disorder. Despite a recent surge of interest in childhood onset bipolar disorder, there remains a scarcity of neuropsychological literature investigating this population. From the study of adult bipolar disorder a substantial body of literature points to the existence of trait deficits in verbal and executive function that are detectable even during euthymia. In the nascent literature on neuropsychology in early onset bipolar, there is growing evidence to suggest that some of the deficits apparent in adults are also discernible in adolescents. Precise knowledge about when, how, and why these deficits appear requires future research of prodromal changes in neurocognition in childhood and adolescent bipolar disorder.

Cognitive functioning in elderly patients with early onset bipolar disorder

BACKGROUND

Very little is known about the long term cognitive sequelae of bipolar disorder.

AIM

To investigate neuropsychological functioning in older euthymic persons with early onset bipolar disorder.

METHOD

Fifteen older patients (age >60) with an early onset (<50 years) bipolar-I disorder in a euthymic mood were tested using a comprehensive neuropsychological test battery. Neuropsychological functioning was compared with that of a sex, age and education-matched group of 15 comparison subjects without mood disorders or memory complaints.

RESULTS

Bipolar subjects scored lower than comparison subjects on selective attention, verbal memory, verbal fluency and mental effort tests.

CONCLUSIONS

The findings suggest that euthymic bipolar patients are impaired across a range of cognitive domains. This could represent a trait-like cognitive disability related to the disease, as the impairments are comparable with those found in younger bipolar patients.

Psychiatric diagnoses and personality traits associated with disadvantageous decision-making

Objective

Decision-making impairment is an important feature of psychiatric disorders. in a large comorbid psychiatric population, we explored the link between decision-making deficit and clinical variables.

Method

We used the Iowa Gambling Task to measure decision-making in 317 patients. Psychiatric diagnoses were made according to the DSM-IV criteria. Self-questionnaires were used to assess several personality traits. The last and most severe suicidal acts were characterized.

Results

(1) After controlling for age and medication intake, a past history of suicide attempt (OR = 2.0 [1.1–3.8]) and normothymic bipolar disorders (OR = 3.4 [1.1–10.5]) were significantly and independently associated with impaired decision-making. (2) Decision-making performance was significantly correlated with affective lability. (3) No association was found between decision-making skills and suicidal characteristics.

Discussion

A lack of statistical power may have masked associations with obsessive-compulsive disorder and anorexia nervosa. We did not control for other cognitive functions except attention.

Conclusion

This study supports the independent association of decision-making impairment with vulnerability to suicidal behaviour but not with substance abuse. Normothymic bipolar disorders, but not unipolar disorders, were also linked to low performance. At the dimensional level, impulsivity and decision-making abilities may be distinct processes. Affective regulation skills appear to be a major influence on decision-making performance and following a relevant therapeutic target.

Cognitive functions in euthymic patients with bipolar disorder

BACKGROUND

Recent studies have focused on the nature of cognitive dysfunction in bipolar patients. The purpose of the current study was to investigate cognitive performance of individuals with bipolar disorder compared to healthy control subjects during a well-established euthymic period.

METHODS

The sample consisted of 27 bipolar euthymic patients and 21 control subjects. Verbal and visual memory performance, attention, executive functions and psychosocial functions were evaluated for each participant.

RESULTS

Bipolar patients showed significant attentional deficit and executive dysfunction and also poor performance on verbal and visual memory tasks compared to the controls. Illness duration and lifetime total episode number and previous episode with psychotic features was associated with worsened performance on attention, executive and memory tasks. Psychosocial functioning was not associated with cognitive deficit.

CONCLUSIONS

The present study showed persistent cognitive impairment on inhibitory control and selective attention as well as poor performance on verbal and visual memory tests in a group of bipolar euthymic patients. The impaired neuropsychological performance was associated with duration of illness, total number of episodes per lifetime, and previous episodes with psychotic features. Attentional dysfunction seemed to be a trait abnormality for the sample studied.

Pyrrolidino-tetrahydroisoquinolines as potent dual H3 antagonist and serotonin transporter inhibitors

A series of novel and potent pyrrolidino-tetrahydroisoquinolines with dual histamine H(3) antagonist/serotonin transporter inhibitor activity is described. A highly regio- and diastereoselective synthesis of the pyrrolidino-tetrahydroisoquinoline core involving acid mediated ring-closure of an acetophenone intermediate followed by reduction with NaCNBH(3) was developed. In vitro and in vivo data are discussed.

Neuropsychological deficits and functional impairment in bipolar depression, hypomania and euthymia

OBJECTIVE

To examine whether patients with bipolar disorder (BD) have subtle neuropsychological deficits that manifest clinically as cognitive and functional compromise, and this study attempted to determine the pattern of such cognitive deficits and their functional impact across all three phases of BD. We hypothesised that euthymia does not equate with normal neuropsychological function and that each phase has a characteristic pattern of deficits, with disturbance in attention and memory being common across all phases of the illness: (i) bipolar depression - psychomotor slowing and impairment of memory; (ii) hypomania by frontal-executive deficits and (iii) euthymia - a mild disturbance of attention, memory and executive function.

METHODS

Twenty-five patients with a diagnosis of bipolar I disorder underwent neuropsychological testing over a period of 30 months in the natural course of their illness while hypomanic and/or depressed and/or euthymic. The results from these assessments were compared with findings from neuropsychological tests conducted on 25 healthy controls matched for age, sex, education and handedness.

RESULTS

Initial analyses revealed modest impairment in executive functioning, memory and attention in both hypomanic and depressed bipolar patients, with additional fine motor skills impairment in the latter. Memory deficits, also noted in euthymic patients, were non-significant after controlling for confounding variables, although bipolar depressed patients remained significantly impaired on tests of verbal recall. Bipolar depressed and hypomanic patients differed with respect to the nature of their memory impairment. Depressed patients were more impaired as compared with euthymic patients on tests of verbal recall and fine motor skills. Psychosocial functioning was impaired across all three patient groups, but only in depressed and hypomanic patients did this correlate significantly with neuropsychological performance.

CONCLUSIONS

The mood-state-related cognitive deficits in both bipolar depression and hypomania compromise psychosocial function when patients are unwell. In euthymic patients, subtle impairments in attention and memory suggest that an absence of symptoms does not necessarily equate to 'recovery'. The possibility of persistent cognitive deficits in BD is an issue of profound clinical and research interest that warrants further investigation; however, future research needs to adopt more sophisticated neuropsychological probes that are able to better define state and trait deficits and determine their functional impact.

[Psychoeducational and cognitive behavioral treatments of bipolar disorder]

Bipolar disorder is a severe mood disorder characterized by recurrence of mania and depression. Despite the use of mood stabilizers, a significant proportion of bipolar patients experience relapse, psychosocial impairment and persistent symptoms. A significant part of patients show poor adhesion to the pharmacological treatment. This article aims to provide an overview of research focusing on psychoeducational and cognitive-behavioral treatment (CBT) of bipolar patients.

METHOD

Studies were identified through Medline searches between 1971 and 2005.

RESULTS

Studies on bipolar patients suggest that psychoeducational interventions may improve treatment adherence, illness knowledge, ability to cope with early manic symptoms and tend to reduce the risk of manic relapses. CBT tends to diminish depressive symptoms, improve treatment adherence and reduce the risk of depressive and manic relapses. Most psychoeducational and CBT studies share a common medical model of the illness, thereby making clear distinctions of impact of each intervention difficult. Few studies focused on patients with problems with mood stabilizers adherence. It is now important to develop specific interventions for those patients.

CONCLUSION

According to these studies, bipolar patients are likely to benefit from psychoeducational or CBT interventions added to usual pharmacotherapy. In order to overcome limitations of existing research, future studies should adjust for the effect of pharmacological treatment, the type and severity of psychopathology at baseline, the acceptance of and the adaptability to the illness and it's awareness.

Reduced activation to implicit affect induction in euthymic bipolar patients: an fMRI study

OBJECTIVE

To examine whether euthymic bipolar patients engage similar or contrasting brain regions as healthy subjects when responding to implicit affect induction.

METHODS

The study examined 10 euthymic patients with bipolar I disorder, and 10 age- and gender-matched healthy subjects using event-related functional magnetic resonance imaging (fMRI) while subjects engaged in a modified word-based memory task designed to implicitly evoke negative, positive or no affective change. The activation paradigm involved nominating whether a target word was contained within a previously presented word list using specified response keys.

RESULTS

The fMRI task produced significantly greater activation in healthy subjects as compared to patients in response to both negative and positive affect in the anterior and posterior cingulate, medial prefrontal cortex, middle frontal and right parahippocampal gyri. Only negative affect produced significantly greater activation in the postcentral gyrus, inferior parietal lobule, thalamus and putamen and only positive affect achieved the same in the precentral, superior temporal and lingual gyri, precuneus, cuneus, caudate, pons, midbrain and cerebellum. There were no brain regions in which responses were greater in patients as compared to healthy subjects. There were no statistically significant differences between the groups with respect to speed or accuracy.

CONCLUSIONS

Diminished prefrontal, cingulate, limbic and subcortical neural activity in euthymic bipolar patients as compared to healthy subjects is suggestive of emotional compromise that is independent of cognitive and executive functioning. This finding is of clinical importance and has implications both for the diagnosis and treatment of bipolar disorder. Future studies should aim to replicate these findings and examine the development of bipolar disorder, investigating in particular the effects of medication.

Altered glucocorticoid receptor signaling cascade in lymphocytes of bipolar disorder patients

Bipolar disorder (BD) is characterized by hypothalamic pituitary adrenal (HPA) axis hyperactivity, glucocorticoid insensitivity and alterations in serotonin and inflammatory mediators. The glucocorticoid receptor (GR), activator protein-1 (AP-1), nuclear factor-kappa B (NF-kappaB) and c-jun N-terminal kinase (JNK) regulate the above mentioned processes; we therefore assessed their role in BD. Fifteen bipolar depressed patients under multiple anti-depressant therapy, 15 bipolar euthymics under lithium monotherapy and 25 matched controls were studied. Whole cell and nuclear extracts from lymphocytes were immunoblotted for GR, c-fos, JNK and NF-kappaB and nuclear aliquots were submitted to electrophoretic mobility shift assay for GR, AP-1 and NF-kappaB. Associations with the anti-depressant therapy and the state of the disease were also sought. Results, expressed as percentage of pooled protein standard sample intergraded optical density (IOD) (mean +/- SD), revealed: (a) depressed patients had significantly higher GR levels than controls in whole cell (82.63 +/- 6.18 versus 76.27 +/- 4.21%, P < 0.01) and nuclear extracts (86.66 +/- 3.81 versus 81.72 +/- 2.71%, P < 0.001) but lower GR-DNA binding (68.75 +/- 7.91 versus 81.84 +/- 4.25%, P < 0.05). Euthymics had normalized whole cell GR content (73.64 +/- 5.95%) and GR-DNA binding activity (76.82 +/- 7.29%) but higher nuclear GR content (86.89+/-3.96%, P<0.01) than controls; (b) nuclear c-fos content and AP-1-DNA-binding were significantly lower in depressed patients than controls (80.49 +/- 2.03 versus 84.82 +/- 3.48%, P < 0.05 and 78.46 +/- 4.17 versus 84.80 +/- 5.79%, P < 0.05, respectively). Euthymics however, showed similar nuclear c-fos and AP-1-DNA-binding to controls (85.48 +/- 2.71 and 87.78 +/- 3.54%, respectively) but lower whole cell c-fos than in controls (81.18 +/- 3.87 versus 87.01 +/- 4.22%, P < 0.001); (c) depressed patients had significantly lower whole cell and nuclear JNK than controls (67.01 +/- 4.29 versus 72.00 +/- 3.68%, P < 0.05 and 80.10 +/- 2.53 versus 86.96 +/- 2.49%, P < 0.001) whereas euthymics showed lower nuclear JNK (83.27 +/- 1.93%, P < 0.01); (d) whole cell NF-kB was higher in the depressed patients than in controls (67.30 +/- 5.00 versus 63.63 +/- 3.3%, P < 0.05). Concluding, intracellular signaling of GR, AP-1 and JNK are altered in BD and may underly disease aetiopathogenesis and/or reflect the effect of the anti-depressants.

Executive functioning and theory of mind in euthymic bipolar disorder

OBJECTIVES

To examine the nature of executive deficits in euthymic patients with bipolar disorder (BD).

METHODS

Fifteen euthymic BD patients and 13 controls were administered a battery of executive tasks including verbal fluency, Stroop, Theory of Mind (ToM) tests and selected subtests from the Cambridge Neuropsychological Test Automated Battery (CANTAB). Self-report and clinician ratings of mood and social and occupational functioning were also obtained.

RESULTS

There were no significant differences between BD patients and controls on the primary measures of the following executive tasks: verbal fluency, attentional set-shifting, problem solving or planning. On secondary measures of speed, BD patients were slower to complete the first trial of the Stroop task (p = 0.001). Patients with BD committed more errors across all secondary measures. Patients performed poorly when compared with controls on tests of verbal ToM (p = 0.02), and although they performed non-verbal ToM tasks at a level comparable to controls (p = 0.60), they were slower to initiate a response (p = 0.006). ToM was not significantly correlated with any measure of social and occupational functioning; however it correlated with the achievement scores of the CANTAB Stockings of Cambridge task (Pearson's r = 0.68, p < 0.01).

CONCLUSIONS

Deficits found in euthymic bipolar patients suggest fronto-subcortical pathway dysfunction. This is consistent with other neuropsychological and neuroimaging research that points to a trait deficit in BD. Further investigation is necessary perhaps using more real-world tests.