Distinguishing bipolar from unipolar depression: the importance of clinical symptoms and illness features

Clinical distinctions in symptomatology and psychiatric comorbidities between misdiagnosed bipolar I and bipolar II disorder versus major depressive disorder

BACKGROUND

To explore the demographic and clinical features of current depressive episode that discriminate patients diagnosed with major depressive disorder (MDD) from those with bipolar I (BP-I) and bipolar II (BP-II) disorder who were misdiagnosed as having MDD .

METHODS

The Mini-International Neuropsychiatric Interview (MINI) assessment was performed to establish DSM-IV diagnoses of MDD, and BP-I and BP-II, previously being misdiagnosed as MDD. Demographics, depressive symptoms and psychiatric comorbidities were compared between 1463 patients with BP-I, BP-II and MDD from 8 psychiatric settings in mainland China. A multinomial logistic regression model was performed to assess clinical correlates of diagnoses.

RESULTS

A total of 14.5% of the enrolled patients initially diagnosed with MDD were eventually diagnosed with BP. Broad illness characteristics including younger age, higher prevalence of recurrence, concurrent dysthymia, suicidal attempts, agitation, psychotic features and psychiatric comorbidities, as well as lower prevalence of insomnia, weight loss and somatic symptoms were featured by patients with BP-I and/or BP-I, compared to those with MDD. Comparisons between BP-I and BP-II versus MDD indicated distinct symptom profiles and comorbidity patterns with more differences being observed between BP-II and MDD, than between BP-I and MDD .

CONCLUSION

The results provide evidence of clinically distinguishing characteristics between misdiagnosed BP-I and BP- II versus MDD. The findings have implications for guiding more accurate diagnoses of bipolar disorders.

Comparing Symptoms of Major Depression in Youth with Confirmed Versus Suspected Bipolar Disorder

Background: While numerous studies have compared symptoms of major depressive episodes (MDEs) associated with bipolar disorder (BD; i.e., bipolar depression) versus major depressive disorder (MDD; i.e., unipolar depression), little is known about this topic in youth. We compared MDE symptoms in youth with BD with youth with suspected BD who have similar clinical and familial characteristics aside from having BD. Methods: MDE symptoms based on Kiddie Schedule for Affective Disorders and Schizophrenia for School Age Children (K-SADS) Depression Rating Scale items for the most severe past episode were compared in youth, ages 13-21 years, with BD (n = 208) versus suspected BD (n = 165). Diagnoses were confirmed via semistructured interviews. Symptoms with between-group differences (p < 0.05) in univariate analyses were evaluated in a multivariate forward stepwise regression. All analyses controlled for age and sex. Results: Youth with BD had significantly higher (more severe) ratings on depressed mood (p = 0.001, η2 = 0.05), irritability (p = 0.037, η2 = 0.02), anhedonia (p = 0.004, η2 = 0.04), negative self-image (p < 0.001, η2 = 0.07), hopelessness (p = 0.04, η2 = 0.02), fatigue (p = 0.001, η2 = 0.05), hypersomnia (p = 0.001, η2 = 0.05), suicidal ideation (p = 0.04, η2 = 0.02), and recurrent thoughts of death (p < 0.001, η2 = 0.05). In regression analyses, the only symptom that remained significant in the BD group was depressed mood (p = 0.002). Conclusions: These findings demonstrate greater severity of depressive symptoms in youth with BD versus MDD across mood, and cognitive and neurovegetative symptom domains. These differences are especially noteworthy given that the MDD group was highly similar to the BD group, aside from BD diagnosis. Present findings emphasize the need for novel treatment approaches to bipolar depression in youth, and for studies examining potential mechanisms underlying the increased severity of bipolar depression.

Psychotic symptoms in bipolar disorder and their impact on the illness: A systematic review

BACKGROUND

Lifetime psychotic symptoms are present in over half of the patients with bipolar disorder (BD) and can have an adverse effect on its course, outcome, and treatment. However, despite a considerable amount of research, the impact of psychotic symptoms on BD remains unclear, and there are very few systematic reviews on the subject.

AIM

To examine the extent of psychotic symptoms in BD and their impact on several aspects of the illness.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. An electronic literature search of six English-language databases and a manual search was undertaken to identify published articles on psychotic symptoms in BD from January 1940 to December 2021. Combinations of the relevant Medical Subject Headings terms were used to search for these studies. Articles were selected after a screening phase, followed by a review of the full texts of the articles. Assessment of the methodological quality of the studies and the risk of bias was conducted using standard tools.

RESULTS

This systematic review included 339 studies of patients with BD. Lifetime psychosis was found in more than a half to two-thirds of the patients, while current psychosis was found in a little less than half of them. Delusions were more common than hallucinations in all phases of BD. About a third of the patients reported first-rank symptoms or mood-incongruent psychotic symptoms, particularly during manic episodes. Psychotic symptoms were more frequent in bipolar type I compared to bipolar type II disorder and in mania or mixed episodes compared to bipolar depression. Although psychotic symptoms were not more severe in BD, the severity of the illness in psychotic BD was consistently greater. Psychosis was usually associated with poor insight and a higher frequency of agitation, anxiety, and hostility but not with psychiatric comorbidity. Psychosis was consistently linked with increased rates and the duration of hospitalizations, switching among patients with depression, and poorer outcomes with mood-incongruent symptoms. In contrast, psychosis was less likely to be accompanied by a rapid-cycling course, longer illness duration, and heightened suicidal risk. There was no significant impact of psychosis on the other parameters of course and outcome.

CONCLUSION

Though psychotic symptoms are very common in BD, they are not always associated with an adverse impact on BD and its course and outcome.

Differences in network properties of the structural connectome in bipolar and unipolar depression

BACKGROUND

Differentiation between Bipolar Disorder Depression (BDD) and Unipolar Major Depressive Disorder (MDD) is critical to clinical practice. This study investigated machine learning classification of BDD and MDD using graph properties of Diffusion-weighted Imaging (DWI)-based structural connectome.

METHODS

This study included a large number of medication-free (N =229) subjects: 60 BDD, 95 MDD, and 74 Healthy Control (HC) subjects. DWI probabilistic tractography was performed to create Fractional Anisotropy (FA) and Total Streamline (TS)-based structural connectivity matrices. Global and nodal graph properties were computed from these matrices and tested for group differences. Next, using identified graph properties, machine learning classification (MLC) between BDD, MDD, MDD with risk factors for developing BD (MDD+), and MDD without risk factors for developing BD (MDD-) was conducted.

RESULTS

Communicability Efficiency of the left superior frontal gyrus (SFG) was significantly higher in BDD vs. MDD. In particular, Communicability Efficiency using TS-based connectivity in the left SFG as well as FA-based connectivity in the right middle anterior cingulate area was higher in the BDD vs. MDD- group. There were no significant differences in graph properties between BDD and MDD+. Direct comparison between MDD+ and MDD- showed differences in Eigenvector Centrality (TS-based connectivity) of the left middle frontal sulcus. Acceptable Area Under Curve (AUC) for classification were seen between the BDD and MDD- groups, and between the MDD+ and MDD- groups, using the differing graph properties.

CONCLUSION

Graph properties of DWI-based connectivity can discriminate between BDD and MDD subjects without risk factors for BD.

Resting-state functional connectivity graph-properties correlate with bipolar disorder-risk in young medication-free depressed subjects: Bipolar-risk Resting State Functional Connectivity in Major Depression

BACKGROUND

Major Depressive Disorder (MDD) is frequently associated with risk factors for the development of Bipolar Disorder (BD). Using graph theory, we investigated brain network properties associated with BD risk factors in young MDD subjects.

METHODS

Resting-state fMRI was acquired from a large cohort (N= 104) of medication-free currently depressed participants (25 BD depression (BDD), 79 MDD). Lifetime mania symptom count (LMSC), current Young Mania Rating Scale (YMRS) score, and family history of mood disorders (FHMD) were examined as BD risk factors. Functional connectivity matrices from 280 regions of interests (ROIs) were first entered into the Network Based Statistic (NBS) toolbox to identify connections that varied with each risk factor. Next, within the correlated network for each risk factor, global and nodal graph properties for the top five linked nodes were calculated. Last, using identified graph properties, machine learning classification (MLC) between BDD, MDD with BD risk factors (MDD+), and without BD risk factors (MDD-) was conducted.

RESULTS

LMSC positively correlated with left lateral orbitofrontal cortex (LOFC) Communication Efficiency and with left middle temporal Eigenvector Centrality. Current YMRS score positively correlated with right amygdala Communication Efficiency and Closeness Centrality. FHMD positively correlated with right insula Eigenvector Centrality. Acceptable MLC accuracy was seen between BDD and MDD- using middle temporal Eigenvector Centrality, whereas moderate accuracy was seen between MDD+ and MDD- using OFC Communication Efficiency.

LIMITATION

Although participants were medication-free, they were not medication-naïve.

CONCLUSION

Functional connectome graph properties may serve as BD vulnerability biomarkers in young individuals with MDD.

Symptoms and Characteristics of Youth Hospitalized for Depression: Subthreshold Manic Symptoms Can Help Differentiate Bipolar from Unipolar Depression

Background: Most people who have major depressive disorder (MDD) or bipolar disorder (BD) will have their first episode of depression in adolescence. However, in the absence of significant [hypo]manic symptoms, there are no clear guidelines for distinguishing bipolar from unipolar depression, which can lead to misdiagnosis and ineffective/harmful treatment. We aimed to compare phenomenological differences among youth with MDD or BD hospitalized for an acute episode of depression. Methods: A retrospective electronic chart review of adolescents hospitalized in an acute care inpatient unit who had a discharge diagnosis of MDD, MDD with mixed or psychotic features (MDD+), BD-I-current episode depressed, or BD-II-current episode depressed, was performed. Results: Altogether, 598 patients (mean age = 15.1 ± 1.5 years, female = 71%, and White = 46%) met study inclusion criteria, i.e., BD-I: n = 39, BD-II: n = 84, MDD: n = 422, and MDD+: n = 53 patients. The admission Hamilton Depression Rating Scale (HAMD) total score was significantly higher in the BD-I (29.3 ± 9.1) and MDD+ (31.2 ± 9.3) groups versus the MDD group (24.3 ± 9.7) (p < 0.05). Although there were some group differences in the severity of individual depression symptoms, these did not line up neatly across BD and MDD groups. At admission, Young Mania Rating Scale (YMRS) total scores were significantly higher in the BD-I (14.4 ± 7.4), BD-II (13.8 ± 6.5), and MDD+ groups (14.3 ± 6.6) versus the MDD group (8.2 ± 4.6, p < 0.05). Additionally, 9 of 11 and 4 of 11 YMRS items scored significantly higher in the BD-II and BD-I groups versus the MDD group, respectively. The motor activity and hypersexuality items, in particular, were scored consistently higher in the BD groups than MDD groups. Limitations: All diagnoses were made based on a clinical interview and not a structured diagnostic interview, and some of the subgroup sample sizes were relatively modest, limiting the power for group comparisons. Conclusion: The presence of subsyndromal manic symptoms during an episode of MDD currently offers the clearest way by which to differentiate bipolar depression from unipolar depression.

Discriminating bipolar depression from major depressive disorder with polygenic risk scores

BACKGROUND

Although accurate differentiation between bipolar disorder (BD) and unipolar major depressive disorder (MDD) has important prognostic and therapeutic implications, the distinction is often challenging based on clinical grounds alone. In this study, we tested whether psychiatric polygenic risk scores (PRSs) improve clinically based classification models of BD v. MDD diagnosis.

METHODS

Our sample included 843 BD and 930 MDD subjects similarly genotyped and phenotyped using the same standardized interview. We performed multivariate modeling and receiver operating characteristic analysis, testing the incremental effect of PRSs on a baseline model with clinical symptoms and features known to associate with BD compared with MDD status.

RESULTS

We found a strong association between a BD diagnosis and PRSs drawn from BD (R2 = 3.5%, p = 4.94 × 10-12) and schizophrenia (R2 = 3.2%, p = 5.71 × 10-11) genome-wide association meta-analyses. Individuals with top decile BD PRS had a significantly increased risk for BD v. MDD compared with those in the lowest decile (odds ratio 3.39, confidence interval 2.19-5.25). PRSs discriminated BD v. MDD to a degree comparable with many individual symptoms and clinical features previously shown to associate with BD. When compared with the full composite model with all symptoms and clinical features PRSs provided modestly improved discriminatory ability (ΔC = 0.011, p = 6.48 × 10-4).

CONCLUSIONS

Our study demonstrates that psychiatric PRSs provide modest independent discrimination between BD and MDD cases, suggesting that PRSs could ultimately have utility in subjects at the extremes of the distribution and/or subjects for whom clinical symptoms are poorly measured or yet to manifest.

Probing the clinical and brain structural boundaries of bipolar and major depressive disorder

Bipolar disorder (BD) and major depressive disorder (MDD) have both common and distinct clinical features, that pose both conceptual challenges in terms of their diagnostic boundaries and practical difficulties in optimizing treatment. Multivariate machine learning techniques offer new avenues for exploring these boundaries based on clinical neuroanatomical features. Brain structural data were obtained at 3 T from a sample of 90 patients with BD, 189 patients with MDD, and 162 healthy individuals. We applied sparse partial least squares discriminant analysis (s-PLS-DA) to identify clinical and brain structural features that may discriminate between the two clinical groups, and heterogeneity through discriminative analysis (HYDRA) to detect patient subgroups with reference to healthy individuals. Two clinical dimensions differentiated BD from MDD (area under the curve: 0.76, P < 0.001); one dimension emphasized disease severity as well as irritability, agitation, anxiety and flight of ideas and the other emphasized mostly elevated mood. Brain structural features could not distinguish between the two disorders. HYDRA classified patients in two clusters that differed in global and regional cortical thickness, the distribution proportion of BD and MDD and positive family history of psychiatric disorders. Clinical features remain the most reliable discriminant attributed of BD and MDD depression. The brain structural findings suggests that biological partitions of patients with mood disorders are likely to lead to the identification of subgroups, that transcend current diagnostic divisions into BD and MDD and are more likely to be aligned with underlying genetic variation. These results set the foundation for future studies to enhance our understanding of brain-behavior relationships in mood disorders.

Psychometric Properties of the Chinese Version of the Bipolar Depression Rating Scale for Bipolar Disorder

INTRODUCTION

Unlike unipolar depression, depressive episode of bipolar disorder is often associated with clinical characteristics, such as atypical and mixed symptoms. However, there are currently no valid and reliable specific tools available to assess the specific psychiatric symptomatology of depressive episode of bipolar disorder in China. Therefore, we aimed to evaluate the psychometric properties of the Chinese version of the Bipolar Depression Rating Scale (BDRS) in Chinese patients with bipolar disorder.

METHODS

The sample of this study included 111 patients with bipolar disorder (30 male, 81 female). All participants were interviewed with the Chinese version of the BDRS (BDRS-C), the 17-item Hamilton Depression Rating Scale (HAMD-17), the Montgomery-Asberg Depression Rating Scale (MADRS) and the Young Mania Rating Scale (YMRS). A psychometric analysis of the BDRS was conducted.

RESULTS

The Cronbach's alpha coefficient of the BDRS-C reached a value of 0.869. The BDRS-C score and scores for the HAMD-17 (r = 0.819, p < 0.01), the MADRS (r = 0.882, p < 0.01) and the YMRS (r = 0.355, p < 0.01) exhibited significant positive correlations. Close correlations were observed between the mixed subscale score of the BDRS-C and the YMRS score (r = 0.784, p < 0.01). Exploratory factor analysis resulted in three factors: a primary depressive symptoms cluster, a secondary depressive symptoms cluster, and a mixed symptoms cluster.

CONCLUSION

The Chinese version of the BDRS has satisfactory psychometric properties. This is a valid and reliable instrument to assess depressive symptomatology in patients with bipolar disorder.

Neurophysiological markers of attention distinguish bipolar disorder and unipolar depression

BACKGROUND

Attentional deficits are common in both symptomatic and symptom-remitted patients with bipolar disorder (BP) and major depressive disorder (MDD). However, whether the level of neurocognitive impairment in attentional processing is different between these two disorders, or not, is still unclear. Thus, we investigated the P300 event-related potential component as a biomarker of cognitive dysfunction to differentiate BP and MDD.

METHODS

Twenty-three age and gender matched BP, 20 MDD and 23 healthy controls (HC) were part of a discovery cohort to identify neurophysiological differences between groups and build a classification model of these disorders. The replication of this model was then tested in an independent second cohort of 17 BP, 19 MDD and 19 HC. All participants were symptom-remitted for at least two weeks. We compared neural responses to target stimuli during an auditory oddball task, computing peak amplitude and latency of the P300 component extracted from the midline centro-parietal electrode.

RESULTS

BP had significantly smaller P300 amplitudes compared to both MDD and HC, whereas there were no differences between MDD and HC. The differences between groups were replicated in the second cohort, however the accuracy level of the classification model was only 53.5%.

LIMITATIONS

Small sample sizes may have led to low accuracy levels of the classification model.

CONCLUSION

Specific neural mechanisms of attention and context updating seem not to recover with symptom remission in BP. These findings contribute to the detection of a potential electrophysiological marker for BP, which may allow its differentiation from unipolar major depressive disorder.

Symptom networks in acute depression across bipolar and major depressive disorders: A network analysis on a large, international, observational study

Major Depressive Episode (MDE) is a transdiagnostic nosographic construct straddling Major Depressive (MDD) and Bipolar Disorder (BD). Prognostic and treatment implications warrant a differentiation between these two disorders. Network analysis is a novel approach that outlines symptoms interactions in psychopathological networks. We investigated the interplay among depressive and mixed symptoms in acutely depressed MDD/BD patients, using a data-driven approach. We analyzed 7 DSM-IV-TR criteria for MDE and 14 researched-based criteria for mixed features (RBDC) in 2758 acutely depressed MDD/BD patients from the BRIDGE-II-Mix study. The global network was described in terms of symptom thresholds and symptom centrality. Symptom endorsement rates were compared across diagnostic subgroups. Subsequently, MDD/BD differences in symptom-network structure were examined using permutation-based network comparison test. Mixed symptoms were the most central and highly interconnected nodes in the network, particularly agitation followed by irritability. Despite mixed symptoms, appetite gain and hypersomnia were significantly more endorsed in BD patients, associations between symptoms were highly correlated across MDD/BD (Spearman's r = 0.96, p<0.001). Network comparison tests showed no significant differences among MDD/BD in network strength, structure, or specific edges, with strong edges correlations (0.66-0.78). Upstream differences in MDD/BD may produce similar symptoms networks downstream during acute depression. Yet, mixed symptoms, appetite gain and hypersomnia are associated to BD rather than MDD. Symptoms during mixed-MDE might aggregate according to 2 different clusters, suggesting a possible stratification within mixed states. Future symptom-based studies should implement clinical, longitudinal, and biological factors, in order to establish tailored therapeutic strategies for acute depression.

The role of different patterns of psychomotor symptoms in major depressive episode: Pooled analysis of the BRIDGE and BRIDGE-II-MIX cohorts

BACKGROUND

Psychomotor agitation (PA) or retardation (PR) during major depressive episodes (MDEs) have been associated with depression severity in terms of treatment-resistance and course of illness.

OBJECTIVES

We investigated the possible association of psychomotor symptoms (PMSs) during a MDE with clinical features belonging to the bipolar spectrum.

METHODS

The initial sample of 7689 MDE patients was divided into three subgroups based on the presence of PR, PA and non-psychomotor symptom (NPS). Univariate comparisons and multivariate logistic regression models were performed between subgroups.

RESULTS

A total of 3720 patients presented PR (48%), 1971 showed PA (26%) and 1998 had NPS (26%). In the PR and PA subgroups, the clinical characteristics related to bipolarity, along with the diagnosis of bipolar disorder (BD), were significantly more frequent than in the NPS subgroup. When comparing PA and PR patients, the former presented higher rates of bipolar spectrum features, such as family history of BD (OR = 1.39, CI = 1.20-1.61), manic/hypomanic switches with antidepressants (OR = 1.28, CI = 1.11-1.48), early onset of first MDE (OR = 1.40, CI = 1.26-1.57), atypical (OR = 1.23, CI = 1.07-1.42) and psychotic features (OR = 2.08, CI = 1.78-2.44), treatment with mood-stabilizers (OR = 1.39, CI = 1.24-1.55), as well as a BD diagnosis according to both the DSM-IV criteria and the bipolar specifier criteria. When logistic regression model was performed, the clinical features that significantly differentiated PA from PR were early onset of first MDE, atypical and psychotic features, treatment with mood-stabilizers and a BD diagnosis according to the bipolar specifier criteria.

CONCLUSIONS

Psychomotor symptoms could be considered as markers of bipolarity, illness severity, and treatment complexity, particularly if PA is present.

Comparison of blood lipid profile/thyroid function markers between unipolar and bipolar depressed patients and in depressed patients with anhedonia or suicidal thoughts

Background

This study aimed to investigate the differences in the serum levels of glucose, lipid, and thyroid function markers between unipolar and bipolar depressed patients, as well as the effect of anhedonia and suicidal thoughts on the levels of these biochemical parameters.

Methods

A total of 287 unmedicated depressed patients from January 2016 to December 2017 were included in this study, including 92 bipolar depressions and 195 unipolar depressions. Anhedonia was determined using the item 32 of Symptom Checklist (SCL-90). Suicide ideation was assessed by item 15 of SCL-90.

Results

The bipolar group had significantly lower lipid levels (including triglycerides, cholesterol, low-density lipoprotein cholesterol [LDL], very low-density lipoprotein cholesterol [VLDL]) and insulin resistance index but higher levels of prolactin, low triiodothyronine (T3) and free T3 (FT3) as well as higher incidence of anhedonia as compared with the unipolar group. Depressed patients with anhedonia had significantly higher LDL level than those without anhedonia. Depressed patients with suicidal thoughts had cholesterol and high-density lipoprotein cholesterol (HDL) level. The above-mentioned differences were confirmed by logistic regression analysis. Receiver operating characteristic curve (ROC) analysis showed that the area under the ROC curve (AUC) ranged from 0.546 to 0.685.

Conclusion

Triglycerides, cholesterol, LDL, VLDL T3, FT3 levels were significantly different between unipolar and bipolar depressed patients, which might have the potential to be the markers for differential diagnosis. Patients with anhedonia had lower LDL level, while patients with suicidal thoughts had higher levels of cholesterol and HDL as compared with the corresponding control groups.

Sub-threshold bipolar disorder in medication-free young subjects with major depression: Clinical characteristics and antidepressant treatment response

BACKGROUND

This study, for the first time, compared illness and antidepressant response characteristics of young subjects with major depression (MDD) at low (LRMDD) or high-risk (HRMDD) for developing bipolar disorder with characteristics of young bipolar (BPD) subjects and healthy controls (HC).

METHODS

One hundred and six young (15-30 yr), medication-free subjects MDD subjects (HRMDD, N = 51; LRMDD, N = 55) were compared with 32 BPD (Type I: 14; Type II: 18) as well as 49 HC subjects. Baseline illness characteristics and frequency of comorbid conditions were examined using Analysis of Variance and Cochran-Armitage trend test. Additionally, in MDD subjects, the effect of open-label antidepressant treatment for up to 24 months with periodic assessments was compared between HRMDD and LRMDD groups for treatment response, remission and (hypo)mania switch while controlling for attrition.

RESULTS

Significant gradation from LRMDD to HRMDD to BPD groups was found for increasing occurrence of alcohol dependence (p = 0.006), comorbid PTSD (p = 0.006), borderline personality traits (p = 0.001), and occurrence of melancholic features (p < 0.005). Antidepressant treatment response was similar between the two groups except that for the 12-month period HRMDD showed a trend for a lower response. Switch to (hypo)mania was infrequent in both groups though the HRMDD showed a higher occurrence of spikes in (hypo)mania symptoms (>25% increase in YMRS scores)(p = 0.04).

CONCLUSION

Findings of the study indicate that a substantial proportion of young MDD subjects share BPD illness characteristics. These HRMDD subjects, if treated with antidepressants, need to be monitored for development of BPD.

TRIAL REGISTRATION

NCT01811147.

Can P300 aid in the differential diagnosis of unipolar disorder versus bipolar disorder depression? A meta-analysis of comparative studies

BACKGROUND

It is difficult to distinguish between bipolar disorder (BD) and unipolar disorder (UD) depression. Given the different pattern of cognitive impairments between BD and UD, P300 is potentially useful for the differential diagnosis. This meta-analysis was performed to estimate the extent of difference in P300 in patients with BD versus UD depression.

METHODS

Studies comparing P300 between depressed BD and UD patients with or without healthy controls (HCs) were retrieved from major English and Chinese databases. Studies with BD and UD samples that were comparable in terms of age, gender, and depression severity, were rated as having high quality. Standardized mean differences (SMDs) of P300 latency and amplitude were calculated.

RESULTS

In total, eight studies with a total of 397 depressed BD patients, 390 depressed UD patients, and 497 HCs, were included. Among included studies, six were rated as having good quality and three followed BD (n = 146) and UD (n = 144) patients during remission. BD patients had significantly longer P300 latency than UD patients during major depressive episode [SMD (95%CI): 0.580 (0.309, 0.850)] and remission [SMD (95%CI): 1.583 (1.322, 1.844)]. Compared to HCs, remitted BD patients still had significantly longer P300 latency [SMD (95%CI): 0.857 (0.059, 1.656)] but P300 latency of remitted UD patients had decreased to normal [SMD (95%CI): 0.536 (-0.272, 1.343)].

LIMITATIONS

Sample sizes of depressed and remitted patients with BD and UD of included studies are small.

CONCLUSIONS

P300 latency can be used as an auxiliary diagnostic marker for differentiating BD from UD depression.

Sociodemographic characteristics of adult Saudi patients with mood disorder subtypes

Background:

The demographic profile and clinical manifestations of mood disorder subtypes can differ across regions; however, there is a lack of studies from Saudi Arabia on the sociodemographic characteristics of adult Saudi patients with mood disorder subtypes.

Objective:

The study aims to explore the sociodemographic profile of adult Saudi patients with different types of mood disorders.

Methods:

This retrospective study analyzed the data of all adult Saudi patients (aged ≥18 years) who were diagnosed with a mood disorder and attended the psychiatric outpatient clinic at King Fahd Hospital of the University (KFHU), Al Khobar, Saudi Arabia, between 1982 and 2011. Patients with psychiatric comorbidity were not included in the analyses. Major depressive disorder (depression), bipolar disorder, adjustment disorder and dysthymia were the four subtypes of mood disorder identified in the sample, and all eligible patients were categorized accordingly.

Results:

A total of 340 patients were included in this study. Slightly less than half (42.4%) the study population were aged 18–30 years. Further, 58% of the patients were females, 67.6% were married and 58.8% were unemployed. Depression was the most common mood disorder (~73%). Of the patients with bipolar disorder (n = 38), more than half were male and aged 18–30 years (~58% each); these percentages were higher than that observed in other subtypes.

Conclusion:

This study found that among patients at KFHU, depression is the most common mood disorder and that most patients are females. In contrast, bipolar disorder is more common among males. Further in-depth studies in a larger sample size may provide better patient profiling, which can be used for developing effective screening programs.

The utility of an RDoC motor domain to understand psychomotor symptoms in depression

Despite the clinical impact of motor symptoms such as agitation or retardation on the course of depression, these symptoms are poorly understood. Novel developments in the field of instrumentation and mobile devices allow for dimensional and continuous recording of motor behavior in various settings, particularly outside the laboratory. Likewise, the use of novel assessments enables to combine multimodal neuroimaging with behavioral measures in order to investigate the neural correlates of motor dysfunction in depression. The research domain criteria (RDoC) framework will soon include a motor domain that will provide a framework for studying motor dysfunction in mood disorders. In addition, new studies within this framework will allow investigators to study motor symptoms across different stages of depression as well as other psychiatric diagnoses. Finally, the introduction of the RDoC motor domain will help test how motor symptoms integrate with the original five RDoC domains (negative valence, positive valence, cognitive, social processes, and arousal/regulation).

Physical activity is associated with left corticospinal tract microstructure in bipolar depression

Psychomotor retardation and reduced daily activities are core features of the depressive syndrome including bipolar disorder (BD). It was the aim of this study to investigate white matter microstructure of the motor system in BD during depression and its association with motor activity. We hypothesized reduced physical activity, microstructural alterations of motor tracts and different associations between activity levels and motor tract microstructure in BD. Nineteen bipolar patients with a current depressive episode (BD) and 19 healthy controls (HC) underwent diffusion weighted magnetic resonance imaging (DW-MRI)-scans. Quantitative motor activity was assessed with 24 h actigraphy recordings. Bilateral corticospinal tracts (CST), interhemispheric connections between the primary motor cortices (M1) and between the pre-supplementary motor areas (pre-SMA) were reconstructed individually based on anatomical landmarks using Diffusion Tensor Imaging (DTI) based tractography. Mean fractional anisotropy (FA) was sampled along the tracts. To enhance specificity of putative findings a segment of the optic radiation was reconstructed as comparison tract. Analyses were complemented with Tract Based Spatial Statistics (TBSS) analyses. BD had lower activity levels (AL). There was a sole increase of fractional anisotropy (FA) in BD in the left CST. Further, there was a significant group x AL interaction for FA of the left CST pointing to a selective positive association between FA and AL in BD. The comparison tract and TBSS analyses did not detect significant group differences. Our results point to white matter microstructure alterations of the left CST in BD. The positive association between motor activity and white matter microstructure suggests a compensatory role of the left CST for psychomotor retardation in BD.

•

Daily physical activity is reduced in bipolar patients with a current depressive episode (BD)

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The left corticospinal tract (CST) in BD shows increased fractional anisotropy (FA)

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Increases of FA in the left corticospinal tract in BD are related to less pronounced psychomotor retardation

A mania-related memory bias is associated with risk for relapse in bipolar disorder<sup/>

OBJECTIVE

Previous work has shown that neuropsychological performance can predict outcome of psychotherapy. The present paper explores whether an affective bias in verbal memory is associated with recurrence of mood episodes in patients with Bipolar Disorder (BD).

METHOD

76 euthymic adult patients with BD were randomly assigned to either 9 months of Cognitive Behavioral Therapy (CBT) or Support Therapy (ST), and followed up for 2 years after completing therapy. At baseline, affective learning memory (Emotional Auditory Verbal Learning Test; EMO-AVLT) and other measures were assessed. Recurrence of a mood episode was the primary outcome.

RESULTS

The survival analyses revealed that the interaction between therapy condition, more specifically ST, and a recognition bias in favor of mania-related, but not depression-related words predicted recurrence of mania. Recurrence of depression was predicted by neither affective memory bias nor their interaction with treatment.

CONCLUSIONS

A mania-related memory bias emerged as a predictor of mania recurrence, specifically in an unstructured setting such as ST. Perhaps mania-related schemata are more salient or more easily activated in those at high risk for recurrence. Interventions targeting patients' insight into their internal states as potential indicators of prodromal manic symptoms could be the key to improve the outcome of psychological interventions in BD. Additional research in the role of cognitive factors in relapse prevention is warranted.

Clinical predictors of conversion to bipolar disorder in a prospective longitudinal familial high-risk sample: focus on depressive features

BACKGROUND

Identifying clinical features that predict conversion to bipolar disorder (BD) in those at high familial risk (HR) would assist in identifying a more focused population for early intervention.

METHOD

In total 287 participants aged 12-30 (163 HR with a first-degree relative with BD and 124 controls (CONs)) were followed annually for a median of 5 years. We used the baseline presence of DSM-IV depressive, anxiety, behavioural and substance use disorders, as well as a constellation of specific depressive symptoms (as identified by the Probabilistic Approach to Bipolar Depression) to predict the subsequent development of hypo/manic episodes.

RESULTS

At baseline, HR participants were significantly more likely to report ⩾4 Probabilistic features (40.4%) when depressed than CONs (6.7%; p < .05). Nineteen HR subjects later developed either threshold (n = 8; 4.9%) or subthreshold (n = 11; 6.7%) hypo/mania. The presence of ⩾4 Probabilistic features was associated with a seven-fold increase in the risk of 'conversion' to threshold BD (hazard ratio = 6.9, p < .05) above and beyond the fourteen-fold increase in risk related to major depressive episodes (MDEs) per se (hazard ratio = 13.9, p < .05). Individual depressive features predicting conversion were psychomotor retardation and ⩾5 MDEs. Behavioural disorders only predicted conversion to subthreshold BD (hazard ratio = 5.23, p < .01), while anxiety and substance disorders did not predict either threshold or subthreshold hypo/mania.

CONCLUSIONS

This study suggests that specific depressive characteristics substantially increase the risk of young people at familial risk of BD going on to develop future hypo/manic episodes and may identify a more targeted HR population for the development of early intervention programs.

Between a rock-a-bye and a hard place: mood disorders during the peripartum period

Mood disorders including major depressive disorder and bipolar disorder are common during and after pregnancy. Timely identification and appropriate management of mood episodes is essential to maximize maternal well-being and minimize adverse outcomes. Failure to do so results in maternal suffering and impaired child bonding, and has the potential for devastating outcomes including suicide and infanticide. Women are routinely screened for unipolar depression during or after pregnancy but not for bipolar disorder, in spite of the fact that childbirth is associated with a major risk for onset or exacerbation of bipolar disorder. Delays in detection as well as misdiagnosis of bipolar disorder as major depressive disorder may put women at risk of many adverse consequences, including symptom exacerbation, psychiatric hospitalization, and suicide. A thorough psychiatric assessment is necessary to establish diagnosis, to address safety issues, and to formulate a treatment plan. Treatment of mood disorders during pregnancy is complicated by the potential risks of fetal exposure to psychotropic medications, and the use of these medications during the postpartum period may result in infant medication exposure through breastmilk. These risks of psychotropic medication exposure must be weighed against the risk of untreated mood disorders. This review will discuss the pathophysiology, epidemiology, diagnosis, and treatment of mood disorders during pregnancy and the postpartum period. Screening tools that can be used in the primary care and obstetrics settings to assist in identifying women with peripartum mood disorders will also be discussed.

Cognitive component of psychomotor retardation in unipolar and bipolar depression: Is verbal fluency a relevant marker? Impact of repetitive transcranial stimulation

AIMS

In the literature, psychomotor retardation (PMR) is increasingly highlighted as a relevant marker for depression. Currently, we chose to focus on the fluency capacities as an evaluation of the frontal lobes functioning to reach a better understanding of cognitive and neurobiological mechanisms involved in PMR in depression. The aims of this study were: (i) to explore the cognitive component of PMR through the analysis of verbal fluency (VF) performance in unipolar and bipolar depression; and (ii) to examine whether a repetitive transcranial magnetic stimulation treatment could improve concomitantly the PMR and VF capacities, as a relevant marker characteristic of the cognitive component of PMR.

METHODS

Fifteen unipolar and 15 bipolar patients were compared to 15 healthy adults. Before treatment, the results showed VF deficits, particularly marked in the bipolar group. The investigation of the interplay between PMR, VF performance, Montgomery-Åsberg Depression Rating Scale scores, and Montreal Cognitive Assessment scores showed that the deficits in these various dimensions were not homogeneous.

RESULTS

The absence of correlation between the psychomotor retardation scale (the French Retardation Rating Scale for Depression) and VF, and the correlation with MoCA raise the hypothesis of a more global cognitive impairment associated with PMR in the BD group. The repetitive transcranial magnetic stimulation treatment had a positive impact on depression, PMR, and fluency scores.

CONCLUSION

Correlations between the Retardation Rating Scale for Depression and VF performances appeared after treatment, showing the cognitive role of psychomotor functioning in depression. Further analyses, including other cognitive measures in an objective evaluation of PMR, are required for a better understanding of these complex relationships.

Characterizing the experience of auditory verbal hallucinations and accompanying delusions in individuals with a diagnosis of bipolar disorder: A systematic review

OBJECTIVES

The aim of the current study was to inform ongoing attempts to identify clinically meaningful subcategories of auditory verbal hallucination (AVH), and to evaluate evidence that might pertain to the suitability of current psychological interventions for people with bipolar disorder (BD) who experience psychotic symptoms.

METHODS

A comprehensive synthesis of findings on the phenomenology of AVH and delusions in BD is included, alongside a critical review of clinical and cognitive correlates. Studies published in the previous 20 years, until December 2016, were retrieved from the following databases: Embase, CINAHL, MEDLINE, PsycINFO and Web of Science. Thirty-two articles were reviewed after applying a set of predetermined inclusion criteria.

RESULTS

Psychotic symptoms were common in both manic and depressive phases, although higher frequencies were indicated in mania. Few detailed characterizations of AVH phenomenology were identified. Delusions with persecutory, grandiose and referential themes were the most common in BD. AVHs were associated with delusions and there was evidence to suggest that delusion subtype may vary according to mood state and type of AVH. Data on clinical correlates of AVH in BD were sparse. However, the results indicated that cognitive appraisals or interpretations of voices might be different in BD from those established to be predictive of clinical outcomes in schizophrenia spectrum disorders.

CONCLUSIONS

Clear gaps exist in our current understanding of the first-person experience of AVH in BD and the potential relationship to co-occurring symptoms, including delusions. Further research into cognitive interpretations of AVH in BD might inform adapted psychological interventions for psychotic symptoms in this population.

Differential failure to deactivate the default mode network in unipolar and bipolar depression

OBJECTIVES

Neuroimaging studies have revealed evidence of brain functional abnormalities in bipolar depressive disorder (BDD) and major depressive disorder (MDD). However, few studies to date have compared these two mood disorders directly.

METHODS

Matched groups of 26 BDD type I patients, 26 MDD patients and 26 healthy controls underwent functional magnetic resonance imaging (fMRI) while performing the n-back working memory task. A whole-brain ANOVA was used to compare the three groups and clusters of significant difference were examined further using region-of-interest (ROI) analysis.

RESULTS

The whole-brain ANOVA revealed a single cluster of significant difference in the medial frontal cortex. The BDD and MDD patients both showed failure to deactivate in this area compared to the controls. The BDD patients showed significantly greater failure of deactivation than the MDD patients, which was not accounted for by differences in severity or chronicity of illness between them.

CONCLUSIONS

Failure of deactivation, considered to reflect default mode network dysfunction, is present to a greater extent in bipolar than unipolar depression. The study of this network may be useful in the search for brain markers that distinguish the two disorders.

Characteristics of depression among offspring at high and low familial risk of bipolar disorder

OBJECTIVES

Having a parent with bipolar disorder (BP) is a very strong risk factor for developing BP. Similarly, depression among youth is a clinical risk factor for subsequent BP. We evaluated whether mood symptomatology in depressed youth is different between those at high and low familial risk to develop BP.

METHODS

The most severe major depressive episode in BP offspring (N=61) and community control offspring (N=20) was evaluated using expanded depression and mania rating scales derived from the Schedule for Affective Disorders and Schizophrenia for Children Present Version. The results were adjusted for any between-group significant demographic differences and for multiple comparisons.

RESULTS

The severity of depressive symptoms and the percentage of offspring with severe depressive symptoms, especially atypical depressive features, were significantly higher in the depressed offspring of BP parents compared to the depressed controls (P_s <.05). The depressive symptoms were helpful to identify a high-risk group (e.g., odds ratio [OR] for hypersomnia: 22.4, 95% confidence interval [CI]: 1.3-404, P=.04). In addition, there were significantly more depressed offspring of BP parents with subsyndromal manic symptoms than controls (52.5% vs 20%, OR: 4.2, 95% CI: 1.2-14.7, P<.01).

CONCLUSIONS

Depressed BP offspring had more severe depression including atypical depressive symptoms, and were more likely to have subsyndromal mixed manic symptoms than depressed control offspring. Prospective studies to evaluate whether these youth are at high risk to develop BP are warranted. If replicated, the results of this study have important clinical (e.g., treatment of depression in depressed offspring of BP parents) and research implications.

Distinguishing Bipolar Depression from Unipolar Depression in Youth: Preliminary Findings

OBJECTIVES

To identify mood symptoms that distinguishes bipolar disorder (BP) depression versus unipolar depression in youth during an acute depressive episode.

METHODS

Youth with BP (N = 30) were compared with youth with unipolar depression (N = 59) during an acute depressive episode using the depression and mania items derived from the Schedule for Affective Disorders and Schizophrenia for Children (K-SADS)-Present Version. The results were adjusted for multiple comparisons, and any significant between-group differences in demographic, nonmood comorbid disorders, and psychiatric family history.

RESULTS

In comparison with unipolar depressed youth, BP depressed youth had significantly higher scores in several depressive symptoms and all subsyndromal manic symptoms, with the exception of increased goal-directed activity. Among the depressive symptoms, higher ratings of nonsuicidal physical self-injurious acts and mood reactivity, and lower ratings of aches/pains, were the symptoms that best discriminated BP from unipolar depressed youth. Subsyndromal manic symptoms, particularly motor hyperactivity, distractibility, and pressured speech, were higher in BP depressed youth and discriminated BP depressed from unipolar depressed youth.

CONCLUSIONS

The results of this study suggest that it is possible to differentiate BP depression from unipolar depression based on depressive symptoms, and in particular subsyndromal manic symptoms. If replicated, these results have important clinical and research implications.

Treatment recommendations for DSM-5-defined mixed features

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) mixed features specifier provides a less restrictive definition of mixed mood states, compared to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR), including mood episodes that manifest with subthreshold symptoms of the opposite mood state. A limited number of studies have assessed the efficacy of treatments specifically for DSM-5-defined mixed features in mood disorders. As such, there is currently an inadequate amount of data to appropriately inform evidence-based treatment guidelines of DSM-5 defined mixed features. However, given the high prevalence and morbidity of mixed features, treatment recommendations based on the currently available evidence along with expert opinion may be of benefit. This article serves to provide these interim treatment recommendations while humbly acknowledging the limited amount of evidence currently available. Second-generation antipsychotics (SGAs) appear to have the greatest promise in the treatment of bipolar disorder (BD) with mixed features. Conventional mood stabilizing agents (ie, lithium and divalproex) may also be of benefit; however, they have been inadequately studied. In the treatment of major depressive disorder (MDD) with mixed features, the comparable efficacy of antidepressants versus other treatments, such as SGAs, remains unknown. As such, antidepressants remain first-line treatment of MDD with or without mixed features; however, there are significant safety concerns associated with antidepressant monotherapy when mixed features are present, which merits increased monitoring. Lurasidone is the only SGA monotherapy that has been shown to be efficacious specifically in the treatment of MDD with mixed features. Further research is needed to accurately determine the efficacy, safety, and tolerability of treatments specifically for mood episodes with mixed features to adequately inform future treatment guidelines.

The relationship between sensory processing patterns, alexithymia, traumatic childhood experiences, and quality of life among patients with unipolar and bipolar disorders

Several studies documented the involvement of sensory perception in emotional processes. The long-term consequences of traumatic experiences and alexithymia have been demonstrated as well. However, the role of extreme sensory processing patterns, traumatic childhood experiences, and alexithymia has not been thoroughly examined in major affective disorders. The present study aimed to: (1) compare unipolar/bipolar patients with regard to their sensory processing patterns, alexithymia, childhood traumatic experiences and quality of life; (2) examine the correlations between sensory processing patterns and childhood traumatic experiences; (3) investigate the relative contribution of diagnostic groups (unipolar/bipolar), sensory processing patterns, alexithymia, and childhood traumatic experiences in predicting quality of life. The sample included 336 participants, 197 with unipolar and 139 with bipolar disorder. All participants completed the Adolescent/Adult Sensory Profile (AASP), Toronto Alexithymia Scale, Childhood Trauma Questionnaire (CTQ), Beck Depression Inventory (BDI)-II, and Short Form 12 Health Survey version 2 (SF-12). Bipolar patients showed significantly higher physical neglect, emotional abuse, and emotional neglect compared with unipolar patients. Both in unipolar and bipolar groups, lower registration of sensory input as well as hypersensitivity correlated with enhanced childhood trauma events. Reduced sensory sensitivity accounted for 11% of the variance in physical health composite score (PCS) of SF-12 whereas reduced depression accounted for 8% of the variance in mental health composite score (MCS). Furthermore, elevated MCS was predicted by depression, physical and emotional neglect. Sensory processing patterns and childhood traumatic experiences may specifically characterize individuals with major affective disorders and play a role in the prediction of their quality of life.

Are there subtypes of bipolar depression?

OBJECTIVE

To investigate for subtypes of bipolar depression using latent class analysis (LCA).

METHOD

Participants were recruited through a bipolar disorder (BD) clinic. LCA was undertaken using: (i) symptoms reported on the SCID-IV for the most severe lifetime depressive episode; (ii) lifetime illness features such as age at first depressive and hypo/manic episodes; and (iii) family history of BD and unipolar depression. To explore the validity of any demonstrated 'classes', clinical, demographic and treatment correlates were investigated.

RESULTS

A total of 243 BD subjects (170 with BD-I and 73 with BD-II) were included. For the combined sample, we found two robust LCA solutions, with two and three classes respectively. There were no consistent solutions when the BD-I and BD-II samples were considered separately. Subjects in class 2 of the three-class solution (characterised by anxiety, insomnia, reduced appetite/weight loss, irritability, psychomotor retardation, suicidal ideation, guilt, worthlessness and evening worsening) were significantly more likely to be in receipt of government financial support, suggesting a particularly malign pattern of symptoms.

CONCLUSION

Our study suggests the existence of two or three distinct classes of bipolar depression and a strong association with functional outcome.