Phenomenology of mixed states: a principal component analysis study

Dysphoria as trans-diagnostic mood symptom and as lived experience. Lessons from prose, poetry and philosophy

This paper attempts to provide a characterisation of it from a first-person perspective of dysphoria, answering the question 'how it feels like to be dysphoric?'. Starting with a definition of emotions as embodied phenomena that provide the person with a felt motivation to move, a rich characterisation of dysphoria is provided centred on the coenesthetic and kinesthetic feelings inherent to this emotion. To fulfil this task, a selected choice of literary, poetic, theatrical and philosophical texts is used to compensate for the quasi-ineffability of the contrasting feelings inherent to dysphoria. Current definitions of dysphoria only highlight the 'negative' side of dysphoria, including irritability, discontent, surrender and interpersonal resentment. A more accurate characterisation necessitates the recognition of the 'positive' side of dysphoria and the ambiguities and contradictions inherent in this emotion. Dysphoric persons feel burdened by a weight that prevents them from moving and simultaneously incites movement. The inertia that accompanies dysphoria is inextricably tied in with a vital urge, however disordered and purposeless. Dysphoria is experienced both as a deadly stagnation and as a chaotic, wild impulse that brings with it an inane aspiration to explore the darkest parts of one's self in search of a glimmer of meaning and authenticity. This characterisation of dysphoria can help to differentiate it from other emotions such as sadness, anger, anxiety and anguish, and thus to identify it more precisely within the spectrum of mood disorders.

Which mixed depression model? A comparison between DSM-5-defined mixed features and Koukopoulos' criteria

BACKGROUND

The criteria of the Diagnostic and Statistical Manual of Mental Disorders 5th edition "with mixed features specifier" (DSM-5 MFS) are considered controversial since they include only typical manic symptoms. By contrast, Koukopoulos developed an alternative model of mixed depression (MxD) focusing primarily on the excitatory component.

OBJECTIVE

To compare DSM-5 MFS and Koukopoulos' MxD (KMxD) in terms of prevalence, associated clinical variables, and discriminative capacity for bipolar depression in patients with major depressive episode (MDE).

METHODS

A total of 300 patients with MDE-155 with major depressive disorder and 145 with bipolar disorder (BD)-were recruited. The discriminative capacity of DSM-5 MFS and KMxD criteria for BD was estimated using the area under the curves of receiver operating characteristic (ROC_AUC). The clinical variables associated with these two diagnostic constructs were assessed by performing a logistic regression.

RESULTS

A total of 44 and 165 patients met the DSM-5 MFS and KMxD criteria, respectively. The ROC_AUCs and their confidence intervals for BD according to DSM-5 MFS and KMxD were 77.0% (72.0%-82.1%) and 71.9% (66.2%-77.7%), respectively. The optimal thresholds (combining sensitivity and specificity measures) for BD diagnosis were ≥1 (77%/68%) for DSM-5 MFS and ≥3 symptoms (78%/66%) for KMxD. However, considering the DSM-5 MFS cut-off (≥3 symptoms), the specificity (97%) increased at the expense of sensitivity (26%).

CONCLUSIONS

KMxD and DSM-5-MFS showed an overlapping discriminative capacity for bipolar depression. The current diagnostic threshold of DSM-5 MFS did not prove to be very inclusive, if compared with the greater diagnostic sensitivity of KMxD, which also yielded better association with clinical variables related to mixedness.

Exploration of mood spectrum symptoms during a major depressive episode: The impact of contrapolarity-Results from a transdiagnostic cluster analysis on an Italian sample of unipolar and bipolar patients

Background

Subthreshold hypomania during a major depressive episode challenges the bipolar-unipolar dichotomy. In our study we employed a cross-diagnostic cluster analysis - to identify distinct subgroups within a cohort of depressed patients.

Methods

A k-means cluster analysis— based on the domain scores of the Mood Spectrum Self-Report (MOODS-SR) questionnaire—was performed on a data set of 300 adults with either bipolar or unipolar depression. After identifying groups, between-clusters comparisons were conducted on MOODS-SR domains and factors and on a set of sociodemographic, clinical and psychometric variables.

Results

Three clusters were identified: one with intermediate depressive and poor manic symptomatology (Mild), one with severe depressive and poor manic symptomatology (Moderate), and a third one with severe depressive and intermediate manic symptomatology (Mixed). Across the clusters, bipolar patients were significantly less represented in the Mild one, while the DSM-5 “Mixed features” specifier did not differentiate the groups. When compared to the other patients, those of Mixed cluster exhibited a stronger association with most of the illness-severity, quality of life, and outcomes measures considered. After performing pairwise comparisons significant differences between “Mixed” and “Moderate” clusters were restricted to: current and disease-onset age, psychotic ideation, suicidal attempts, hospitalization numbers, impulsivity levels and comorbidity for Cluster B personality disorder.

Conclusions

In the present study, a clustering approach based on a spectrum exploration of mood symptomatology led to the identification of three transdiagnostic groups of patients. Consistent with our hypothesis, the magnitude of subthreshold (hypo)manic symptoms was related to a greater clinical severity, regardless of the main categorical diagnosis.

The 12-Item Self-Rating Questionnaire for Depressive Mixed State (DMX-12) for Screening of Mixed Depression and Mixed Features

For simultaneous screening of mixed features (MF) by DSM-5 and mixed depression (MD) by Benazzi, useful symptoms were extracted from our 12-item dimensional scale for depressive mixed state (DMX-12). Subjects were 190 consecutive cases with major depressive episode (MDE) who visited our clinic. Associations between symptomatological combinations of the DMX-12 and MF or MD were analyzed using receiver operating characteristic (ROC). The rate of MF was 4.2% while that of MD was 22.6%. Eight symptoms (overreactivity, inner tension, racing/crowded thought, impulsivity, irritability, aggression, risk-taking behavior, and dysphoria) with their AUC > 0.6 for ROC curves were specially focused on distinguishing patients with MF or MD from non-mixed patients. By using these 8 symptoms, 40.5% of the overall patients were screened as positive at the same cut-off value (≥13) for both MD and MF. The AUC of ROC curve and sensitivity/specificity were well balanced together with sufficient negative predictive values. The abovementioned 8 symptoms seem to be helpful for primary screening and negative check of DMX with considerable severity during MDE.

Efficacy, Safety, and Tolerability of Theta-Burst Stimulation in Mixed Depression: Design, Rationale, and Objectives of a Randomized, Double-Blinded, Sham-Controlled Trial

INTRODUCTION

Mixed-specifier mood disorders are probably a different subgroup in terms of response to treatment, socio-demographic parameters, course, and family history. Here we describe the rationale and design of a clinical trial aimed to test the efficacy, safety, and tolerability of a non-pharmacological treatment known as theta-burst stimulation (TBS) for treating the mixed depressive episodes of both bipolar (I or II), and unipolar depression.

METHODS

The study is designed as a randomized, sham-controlled, double-blinded clinical trial evaluating TBS for the treatment of moderate or severe major depressive episodes with mixed features of patients receiving at least one first or second-line pharmacological treatment for depressive episodes without adequate response. Ninety adult (18 to 65 years old) patients will be enrolled and submitted to 6-week (comprising 5 consecutive days a week sessions for the first 3 weeks and then 2 days a week for a further 3 week) of inhibitory followed by excitatory TBS in dorsolateral prefrontal cortex. Participants will be assessed using clinical and neuropsychological tests before and after the intervention. The primary outcome is change in Montgomery-Åsberg Depression Scale (MADRS) score over time and across groups. Cognitive parameters will also be assessed with neuropsychological tests.

RESULTS

The clinical results will provide evidence about TBS as an adjunctive treatment for mixed depression treatment and neuropsychological parameters will contribute toward an improved understanding the effects of TBS in cognition.

CONCLUSION

Our results could introduce a novel therapeutic technique for mixed depressive episodes of both bipolar and unipolar disorders.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT04123301; date of registration: 10/10/2019; URL: https://clinicaltrials.gov/ct2/show/NCT04123301?term=NCT04123301&rank=1.

Development of the 12-item questionnaire for quantitative assessment of depressive mixed state (DMX-12)

BACKGROUND

Conventional categorical criteria have limitations in assessing the prevalence and severity of depressive mixed state (DMX). Thus, we have developed a new scale for screening and quantification of DMX and examined the symptomatological structure and severity of DMX in individuals with major depressive episode (MDE).

METHODS

Subjects were 154 patients with MDE (57 males and 97 females; age 13-83 years). Our original Japanese version of the self-administered 12-item questionnaire to assess DMX (DMX-12), together with the Quick Inventory of Depressive Symptomatology Self-Report Japanese version (QIDS-SR-J) and global assessment of functioning, were administered to each participant. The symptomatological structure of the DMX-12 was examined by exploratory factor analysis. Multiple regression analyses were used to analyze factors contributing to the DMX-12 scale. The relationships of this scale with categorical diagnoses (mixed depression by Benazzi and mixed features by DSM-5) were also investigated.

RESULTS

A three-factor model of the DMX-12 was extracted from exploratory factor analysis, namely, "spontaneous instability", "vulnerable responsiveness", and "disruptive emotion/behavior". Multiple regression analyses revealed that age was negatively correlated with total DMX-12 score, while bipolarity and the QIDS-SR-J score were positively correlated. A higher score on the disruptive emotion/behavior subscale was observed in patients with mixed depression and mixed features.

CONCLUSION

The DMX-12 seems to be useful for screening DMX in conjunction with conventional categorical diagnoses. Severely depressed younger subjects with potential bipolarity are more likely to develop DMX. The disruptive emotion/behavior subscale of the DMX-12 may be the most helpful in distinguishing patients with DMX from non-mixed patients.

Evaluating response to mood stabilizers in patients with mixed depression: A study of agreement between three different mania rating scales and a depression rating scale

BACKGROUND

The aim of the present study was to evaluate agreement between three pairs formed by one of three mania scales (Young Mania Rating Scale [YMRS], Bech-Rafaelsen Mania Scale [BRMS], or the Clinician-Administered Rating Scale for Mania [CARS-M]) and a single depression scale (21-item Hamilton Depression Rating Scale [21-HAM-D]) for evaluation of response to mood stabilizers in patients with mixed bipolar disorder.

METHODS

Between 2010 and 2014, 68 consecutive bipolar type I and II outpatients with mixed depression as per DSM-IV-TR and Cincinnati criteria were included in this 8-week open-label trial to randomly receive carbamazepine, lithium carbonate, or valproic acid as monotherapy.

RESULTS

Patterns of response (defined as a reduction of at least 50% in one of the mania scales and on the 21-HAM-D) were strikingly similar: 21-HAM-D+YMRS=22.1%, 21-HAM-D+BRMS=20.6%, and 21-HAM-D+CARS-M=23.5% (p<0.368). Assessment of agreement revealed very high kappa coefficients: 21-HAM-D+YMRS vs. 21-HAM-D+CARS-M, kappa=0.87; 21-HAM-D+YMRS vs. 21-HAM-D+BRMS, kappa=0.78; 21-HAM-D+CARS-M vs. 21-HAM-D+BRMS, kappa=0.91 (p<0.001).

LIMITATIONS

The decision to combine a depression rating scale with any one mania rating scale to assess treatment response in patients with mixed depression is questionable.

CONCLUSIONS

The present study suggests that any one of the three tested mania rating scales (YMRS, BRMS, and CARS-M) can be combined with the 21-HAM-D to assess treatment response in patients with mixed bipolar disorder. This should give clinicians an added measure of confidence in using this strategy until valid, and specific instruments are developed for assessment of mixed states.

Specificity of the Relationships Between Dysphoria and Related Constructs in an Outpatient Sample

Dysphoria has recently been conceptualized as a complex emotional state that consists of discontent and/or unhappiness and a predominantly externalizing mode of coping with these feelings. The Nepean Dysphoria Scale (NDS) was developed on the basis of this model of dysphoria and used in this clinical study to ascertain the specificity of the relationships between dysphoria and relevant domains of psychopathology. Ninety-six outpatients completed the NDS, Symptom Checklist 90-Revised (SCL-90R) and Depression, Anxiety, Stress Scales, 21-item version (DASS-21). The scores on the NDS subscales (Discontent, Surrender, Irritability and Interpersonal Resentment) and total NDS scores correlated significantly with scores on the DASS-21 scales and relevant SCL-90R subscales. Multiple regression analyses demonstrated the following: DASS-21 Depression and Stress each had unique relationships with NDS Discontent and Surrender; DASS-21 Anxiety had a unique relationship with NDS Discontent; SCL-90R Hostility and Paranoid Ideation and DASS-21 Stress each had unique relationships with NDS Irritability; and SCL-90R Paranoid Ideation and DASS-21 Stress, Depression and Anxiety each had unique relationships with NDS Interpersonal Resentment. These findings support the notion that dysphoria is a complex emotional state, with both non-specific and specific relationships with irritability, tension, depression, paranoid tendencies, anxiety, hostility and interpersonal sensitivity. Conceptual rigor when referring to dysphoria should be promoted in both clinical practice and further research.

[Mixed depression and DSM-5: A critical review]

BACKGROUND

Mixed depression is a depressive syndrome characterized by the presence, along with the typical depressive symptoms of depression, of those of over activation and excitation. If sometimes this activation is expressed by classical hypomanic symptoms, it is often observed by means of more subtle expression: inner tension, crowded thoughts, dramatic expression suffering, and unproductive agitation. It is important to identify mixed depression because such patients are particularly at risk of suicidal behaviors, substance abuse and therapeutic resistance. Even if therapeutic strategies continue to be discussed, treatments should rely on mood stabilizers and antipsychotics instead of antidepressants as in pure depression. Even though the concept of mixed depression has been described for more than twenty years, first by Koukopoulos and then by other authors, it had been little studied, especially because it did not appear in international psychiatric classifications. The DSM-IV supported a very narrow conception of the mixed states because the criteria required simultaneous full manic and full depressive syndromes, corresponding only to some dysphoric manias. The recently published DSM-5 proposes modifications in mood and bipolar disorder classifications, and especially introduces the possibility to specify depressive and manic episodes with "mixed features". To diagnose depression with mixed features, a full depressive syndrome has to be present together most of time with three hypomanic symptoms, except symptoms that are considered as overlapping (that can be observed either in mania or in depression), i.e. agitation, irritability and distractibility.

METHODS

Critical analysis of DSM criteria and review of literature.

RESULTS

We first analyzed the clinical relevance of the definition of depression with mixed features which could correspond to mixed depression. The problem is that the hypomanic symptoms allowed by the manual lead to symptom associations that are rather illogical (as euphoria with depression) or improbable (as increased or excessive involvement in activities that have a high potential for painful consequences). Also, some more specific symptoms that can be observed in mixed depression are not mentioned (such as hypersensitivity to light or noise, absence of motor retardation, dramatic expressivity of suffering). The DSM-5, as did DSM-IV, refers to an understanding of mixed depression as a simple addition of depressive and manic symptoms. The classification does not take into account that the symptoms could be rather different from hypomania, as the expression of an overactive thought in a depressed mind. Secondly, we reviewed cohort studies using the DSM-5 criteria (or similar criteria with the exclusion of overlapping symptoms), and as a consequence of the poorly defined symptoms, we found that the diagnosis of mixed depression according to DSM-5 is almost impossible, either in unipolar or in bipolar depression.

CONCLUSIONS

We think, with others, that the definition of the mixed depression by the DSM-5 is not clinically relevant and misses important information about the concept. Clinicians can be attentive to the identification of mixed character in depression, even if DSM-5 criteria are not fully met. Unfortunately, the DSM-5 definition could undermine research efforts for a better understanding of epidemiology, phenomenology and therapeutics of mixed depression. We propose and discuss alternative solutions for defining mixed depression, such as the absence of exclusion of "overlapping" symptoms, a more insighted phenomenology, or a dimensional approach.

Patterns of response to aripiprazole, lithium, haloperidol, and placebo across factor scores of mania

Background

A previous factor analysis of Young Mania Rating Scale and Montgomery-Åsberg Depression Rating Scale items identified composite factors of depression, mania, sleep disturbance, judgment/impulsivity, and irritability/hostility as major components of psychiatric symptoms in acute mania or mixed episodes in a series of trials of antipsychotics. However, it is unknown whether these factors predict treatment outcome.

Methods

Data from six double-blind, randomized, controlled clinical trials with aripiprazole in acute manic or mixed episodes in adults with bipolar I disorder were pooled for this analysis and the previously identified factors were examined for their value in predicting treatment outcome. Treatment efficacy was assessed for aripiprazole (n = 1,001), haloperidol (n = 324), lithium (n = 155), and placebo (n = 694) at baseline, days 4, 7, and 10, and then weekly to study end. Mean change in factor scores from baseline to week 3 was assessed by receiver operating characteristics curves for percentage factor change at day 4 and week 1.

Results

Subjects receiving aripiprazole, haloperidol, and lithium significantly improved mania factor scores versus placebo. Factors most predictive of endpoint efficacy for aripiprazole were judgment/impulsivity at day 4 and mania at week 1. Optimal factor score improvement for outcome prediction was approximately 40% to 50%. Early efficacy predicted treatment outcome across all factors; however, response at week 1 was a better predictor than response at day 4.

Conclusions

This analysis confirms clinical benefits in early treatment/assessment for subjects with bipolar mania and suggests that certain symptom factors in mixed or manic episodes may be most predictive of treatment response.

DSM-5-defined 'mixed features' and Benazzi's mixed depression: which is practically useful to discriminate bipolar disorder from unipolar depression in patients with depression?

AIMS

Irritability, psychomotor agitation, and distractibility in a major depressive episode (MDE) should not be counted as manic/hypomanic symptoms of DSM-5-defined mixed features; however, this remains controversial. The practical usefulness of this definition in discriminating bipolar disorder (BP) from major depressive disorder (MDD) in patients with depression was compared with that of Benazzi's mixed depression, which includes these symptoms.

METHODS

The prevalence of both definitions of mixed depression in 217 patients with MDE (57 bipolar II disorder, 35 BP not otherwise specified, and 125 MDD cases), and their operating characteristics regarding BP diagnosis were compared.

RESULTS

The prevalence of both Benazzi's mixed depression and DSM-5-defined mixed features was significantly higher in patients with BP than it was in patients with MDD, with the latter being quite low (62.0% vs 12.8% [P < 0.0001], and 7.6% vs 0% [P < 0.0021], respectively). The area under the receiver operating curve for BP diagnosis according to the number of all manic/hypomanic symptoms was numerically larger than that according to the number of manic/hypomanic symptoms excluding the above-mentioned three symptoms (0.798; 95% confidence interval, 0.736-0.859 vs 0.722; 95% confidence interval, 0.654-0.790). The sensitivity/specificity of DSM-5-defined mixed features and Benazzi's mixed depression for BP diagnosis were 5.1%/100% and 55.1%/87.2%, respectively.

CONCLUSIONS

DSM-5-defined mixed features were too restrictive to discriminate BP from MDD in patients with depression compared with Benazzi's definition. To confirm this finding, studies that include patients with BP-I and using tools to assess manic/hypomanic symptoms during MDE are necessary.

Different patterns of manic/hypomanic symptoms in depression: A pilot modification of the hypomania checklist-32 to assess mixed depression

BACKGROUND

There are no self-report scales that assess manic/hypomanic symptoms in patients with depression. The aim of this study was to explore the use of a modified screening instrument for bipolar disorder to assess current manic/hypomanic symptoms in patients with a depressive episode.

METHODS

The study sample consisted of 188 patients with Structured Clinical Interview for DSM-IV-TR disorders (SCID) confirmed bipolar or major depressive disorder. We modified the Hypomania Checklist-32 (mHCL-32) to assess current instead of lifetime symptoms. An Exploratory Factor Analysis (EFA) was conducted to identify clusters of mHCL-32 items that were endorsed concurrently. A Latent Class Analysis (LCA) was carried out to identify groups of patients with similar mHCL-32 item endorsement patterns.

RESULTS

The EFA identified 3 factors: factor #1 ("elation-disinhibition-increased goal directed activity"), factor #2 ("risk-taking-impulsivity-substance use") and factor #3 (distractibility-irritability). The LCA yielded 3 classes (2 showing manic/hypomanic features). While class #1 patients endorsed more items related to disinhibition and racing thoughts, class #2 patients recognized more items associated with irritability and substance use.

LIMITATIONS

Lack of an adequate gold standard measure of mixed depression to compare to, the cross-sectional design and the lack of a validation sample.

CONCLUSIONS

The mHCL-32 scale allowed a comprehensive and convergent delineation of hypomanic/manic symptoms in depression. Further validation of these findings is needed.

The significance of mixed states in depression and mania

The DSM-5 definition of mixed features "specifier" of manic, hypomanic and major depressive episodes captures sub-syndromal non-overlapping symptoms of the opposite pole, experienced in bipolar (I, II, and not otherwise specified) and major depressive disorders. This combinatory model seems to be more appropriate for less severe forms of mixed state, in which mood symptoms are prominent and clearly identifiable. Sub-syndromal depressive symptoms have been frequently reported to co-occur during mania. Similarly, manic or hypomanic symptoms during depression resulted common, dimensionally distributed, and recurrent. The presence of mixed features has been associated with a worse clinical course and high rates of comorbidities including anxiety, personality, alcohol and substance use disorders and head trauma or other neurological problems. Finally, mixed states represent a major therapeutic challenge, especially when you consider that these forms tend to have a less favorable response to drug treatments and require a more complex approach than non-mixed forms.

Subjective experience of thought overactivation in mood disorders: beyond racing and crowded thoughts

BACKGROUND

Racing thoughts, crowded thoughts and flight of ideas are frequent symptoms in mood disorders, but the underlying subjective experience of overactivation of thought processes remains poorly documented.

METHODS

Qualitative analysis of audiotaped interviews explored subjective experience of thought overactivation in patients with mood disorders (sample 1, n = 45). Quantitative analysis considered the properties of a newly developed rating scale in sample 1, in an additional sample of patients with mood disorders (sample 2, n = 37) and in healthy subjects (sample 3, n = 38).

RESULTS

Qualitative analysis of individual interviews revealed that 5 conceptual categories characterized thought overactivation: sequential thought flow, overstimulation, competition for resource allocation, unexpected/unexplained onset, and association with mood and emotions. A principal component analysis of the initial 16-item rating scale indicated that a single component explained 55.9% of the variance, with major and exclusive contributions from 9 items, which were retained in the final 9-item Subjective Thought Overactivation Questionnaire (STOQ; Cronbach's α = 0.95). Total score correlated significantly with activation, depression and perceived conflict subscales of the Internal State Scale (ISS; rs = 0.57-0.66, p < 0.001). It was associated with decreased well-being (ISS; rs = -0.48, p = 0.001) and increased state anxiety (State-Trait Anxiety Inventory; rs = 0.60, p < 0.001). The STOQ score was significantly higher in patients than in healthy subjects. It allowed distinguishing between ISS mood states, with the highest median score in mixed states.

LIMITATIONS

Sample size, representativeness, possible bias in qualitative analysis, and quality of expert consensus.

CONCLUSIONS

Qualitative analysis of clinical interviews, together with a new short rating scale, contributed to a documentation of subjective thought overactivation, an important but often undetected feature in mood disorders.

[Clinical description of mixed mania]

DSM-IV mixed states have become the mixed mania and mixed depression in the new DSM-5. One noticeable point is the introduction of nine cations, among which the "with mixed features" specification. These non exclusive specifications may contribute to a more precise identification of mixed clinical pictures, and therefore to offer a more efficient therapeutic answer. Different dimensional approaches are widely documented. They allow the isolation of a mixed factor which is clinically associated with two other specifications: anxious distress and psychotic features. These severity markers may encourage clinicians to be alert about the risk of misdiagnosis, and cautious in the management of these clinical situations.

Mixed states in DSM-5: implications for clinical care, education, and research

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) nomenclature for the co-occurrence of manic and depressive symptoms (mixed states) has been revised in the new DSM-5 version to accommodate a mixed categorical-dimensional concept. The new classification will capture subthreshold non-overlapping symptoms of the opposite pole using a "with mixed features" specifier to be applied to manic episodes in bipolar disorder I (BD I), hypomanic, and major depressive episodes experienced in BD I, BD II, bipolar disorder not otherwise specified, and major depressive disorder. The revision will have a substantial impact in several fields: epidemiology, diagnosis, treatment, research, education, and regulations. The new concept is data-driven and overcomes the problems derived from the extremely narrow definition in the DSM-IV-TR. However, it is unclear how clinicians will deal with the possibility of diagnosing major depression with mixed features and how this may impact the bipolar-unipolar dichotomy and diagnostic reliability. Clinical trials may also need to address treatment effects according to the presence or absence of mixed features. The medications that are effective in treating mixed episodes per the DSM-IV-TR definition may also be effective in treating mixed features per the DSM-5, but new studies are needed to demonstrate it.

Multivariate analysis of bipolar mania: retrospectively assessed structure of bipolar I manic and mixed episodes in randomized clinical trial participants

BACKGROUND

Manic episodes are heterogeneous. Mixed states may differ in important clinical characteristics from other manic episodes. However, it has not been established whether mixed states are a distinct type of episodes, or a common basic structure exists across manic episodes.

METHODS

Using 2179 well-characterized subjects in the pretreatment phase of six randomized, clinical trials, we conducted rotated factor analysis followed by cluster analysis, using all items from the Young Mania Rating Scale and the Montgomery-Åsberg Depression Scale. Analyses were conducted for all subjects (n=2179) and for those in Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition (DSM-IV) mixed (n=644) and non-mixed (n=1535) episodes separately.

RESULTS

There were five factors characterized (in order of variance accounted for) as depression, mania, sleep disturbance, judgment/impulsivity and irritability/hostility. Cluster analysis identified five clusters. Three were predominately manic, with depression scores below average for the overall group. Two had high average depression scores; these clusters differed in irritability/hostility. Judgment/impulsivity scores were similar across factors. Essentially identical factors and clusters existed whether analyses were done in all subjects or only in subjects classified by DSM-IV as mixed or non-mixed.

LIMITATIONS

Exclusion criteria of studies may limit generalizability of findings.

DISCUSSION

All manic episodes, whether mixed or non-mixed, shared a similar structure according to factor/cluster analysis. Patients with high depression factor scores were heterogeneous with respect to irritability. These data suggest that depressive symptoms should be considered a dimensional property across manic episodes, rather than as defining a specific type of episode.

Phenomenology of racing and crowded thoughts in mood disorders: a theoretical reappraisal

BACKGROUND

Racing thoughts is a frequent symptom in mood disorders, particularly mixed depressive states. This paper aims to summarize our current knowledge about its phenomenology and frequency in the spectrum of mood disorders, and to offer a new theoretical framework.

METHODS

We made a selective review of original and review papers in Medline and PsychInfo database using the keywords "racing thoughts", "crowded thoughts" and "depressive mixed state" in conjunction with "mood disorders".

RESULTS

In the context of a hypomanic state, "racing thoughts" may appear as a result from an excessive production of thoughts, moving quickly from one to the other, and generating a sense of fluidity and pleasantness. In the context of depression, "racing thoughts" are phenomenologically different and better described as "crowded thoughts": they are not only characterized by too many thoughts occurring at the same time in the field of consciousness, but perceived as unpleasant and induce the feeling that ideas are difficult to catch. DISCUSSION AND CLINICAL RELEVANCE: We suggest that crowded thoughts might result from the mixture of a hypomanic component, with an accelerated production of new thoughts (constituting the main source of this symptom in hypomania), and a depressive component, with a deficit of inhibition of previous thoughts (hence making thoughts crowded rather than truly racing). This distinction could help better identify crowded thoughts, and consequently depressive mixed states, which has important implications for therapeutic management. It might also help to further disentangle the psychobiological processes which contribute to the complexity of mood disorders.

Continuum of depressive and manic mixed states in patients with bipolar disorder: quantitative measurement and clinical features

Bipolar mixed states combine depressive and manic features, presenting diagnostic and treatment challenges and reflecting a severe form of the illness. DSM-IV criteria for a mixed state require combined depressive and manic syndromes, but a range of mixed states has been described clinically. A unified definition of mixed states would be valuable in understanding their diagnosis, mechanism and treatment implications. We investigated the manner in which depressive and manic features combine to produce a continuum of mixed states. In 88 subjects with bipolar disorder (DSM-IV), we evaluated symptoms and clinical characteristics, and compared depression-based, mania-based, and other published definitions of mixed states. We developed an index of the extent to which symptoms were mixed (Mixed State Index, MSI) and characterized its relationship to clinical state. Predominately manic and depressive mixed states using criteria from recent literature, as well as Kraepelinian mixed states, had similar symptoms and MSI scores. Anxiety correlated significantly with depression scores in manic subjects and with mania scores in depressed subjects. Discriminant function analysis associated mixed states with symptoms of hyperactivity and negative cognitions, but not subjective depressive or elevated mood. High MSI scores were associated with severe course of illness. For depressive or manic episodes, characteristics of mixed states emerged with two symptoms of the opposite polarity. This was a cross-sectional study. Mixed states appear to be a continuum. An index of the degree to which depressive and manic symptoms combine appears useful in identifying and characterizing mixed states. We propose a depressive or manic episode with three or more symptoms of the opposite polarity as a parsimonious definition of a mixed state.

Rating scales in bipolar disorder

PURPOSE OF REVIEW

Bipolar disorder is a complex clinical entity that presents with pleomorphic signs and symptoms varying from depression to hypomania, full-blown mania, mixed states, and psychosis. Therefore, the assessment of patients with bipolar disorder poses a difficult challenge to clinicians, who may find themselves puzzled when having to choose among the many instruments available. This paper aims at briefly reviewing these instruments.

RECENT FINDINGS

Observer-rated and self-completed instruments for the assessment of depressive, manic, and psychotic symptoms in patients with bipolar disorder are described with emphasis on topics of increasing interest in recent times, such as the assessment of bipolar depression, self-rating of manic symptoms, daily mood monitoring, screening, and early recognition of bipolar disorder.

SUMMARY

The use of standardized assessment instruments has many advantages as it enables clinicians to be more systematic and it allows greater precision, increased sensitivity to change, and opportunity to identify longitudinal patterns. Knowledge of available options for the assessment of patients with bipolar disorder may help clinicians and researchers to choose the most appropriate instruments for their specific needs.