Depressive mixed state frequency: age/gender effects

Bipolar Depression: A Historical Perspective of the Current Concept, with a Focus on Future Research

The aim of this narrative review is to trace the origin of the concept of bipolar depression and to expose some of its limitations. Bipolar depression is a broad clinical construct including experiences ranging from traditional melancholic and psychotic episodes ascribed to "manic-depressive insanity," to another heterogeneous group of depressive episodes originally described in the context of binary models of unipolar depression (e.g., psychogenic depression, neurotic depression). None of the available empirical evidence suggests, however, that these subsets of "bipolar" depression are equivalent in terms of clinical course, disability, family aggregation, and response to treatment, among other relevant diagnostic validators. Therefore, the validity of the current concept of bipolar depression should be a matter of concern. Here, we discuss some of the potential limitations that this broad construct might entail in terms of pathophysiological, clinical, and therapeutic aspects. Finally, we propose a clinical research program for bipolar depression in order to delimit diagnostic entities based on empirical data, with subsequent validation by laboratory or neuroimaging biomarkers. This process will then aid in the development of more specific treatments.

Validity of the Shahin Mixed Depression Scale: A Self-Rated Instrument Designed to Measure the Non-DSM Mixed Features in Depression

BACKGROUND

The DSM5-defined mixed features in depression do not include psychomotor agitation, irritability or distractibility because they are considered overlapping symptoms. A growing number of modern psychiatrists have expressed dissatisfaction with this and proposed alternative sets of mixed symptoms that are much more common and clinically relevant. Among such alternative criteria were those proposed by Koukopoulos. He utilized the research diagnostic criteria of agitated depression (RDC-A) as a mixed depression subtype, and validated another form of mixed depression, the Koukopoulos criteria for mixed depression (K-DMX).

PURPOSE

This study provides psychometric validation for the first self-rated scale designed to measure the most common mixed symptoms in depression as proposed by Koukopoulos.

PATIENTS AND METHODS

We conducted a multicenter cross-sectional study of 170 patients with unipolar depression. They completed the Shahin Mixed Depression Scale (SMDS) and underwent expert interviews as a gold standard reference. SMDS' psychometric properties were assessed, including Cronbach's alpha, factor analysis, sensitivity, specificity, predictive value and accuracy.

RESULTS

We found significant association and agreement between mixity according to SMDS and the gold standard (K-DMX and RDC-A according to expert interview) with good internal consistency (Cronbach's alpha=0.87), high sensitivity (=91.4%), specificity (=98.0%), positive predictive value (=96.9%), negative predictive value (= 94.2%) and accuracy (=95.2%). Factor analysis identified one factor for psychomotor agitation and another for mixity without psychomotor agitation.

CONCLUSION

SMDS was a reliable and valid instrument for assessing the frequently encountered and clinically relevant mixed features in depression.

[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.

Mixed depression: clinical features and predictors of its onset associated with antidepressant use

BACKGROUND

Mixed depression (MxD) is narrowly defined in the DSM-IV and somewhat broader in the DSM-5, although both exclude psychomotor agitation as a diagnostic criterion. This article proposes a clinical description for defining MxD, which emphasizes psychomotor excitation.

METHODS

Two hundred and nineteen consecutive outpatients were diagnosed with an MxD episode using criteria proposed by Koukopoulos et al. [Acta Psychiatr Scand 2007;115(suppl 433):50-57]; we here report their clinical features and antidepressant-related effects.

RESULTS

The most frequent MxD symptoms were: psychic agitation or inner tension (97%), absence of retardation (82%), dramatic description of suffering or weeping spells (53%), talkativeness (49%), and racing or crowded thoughts (48%). MxD was associated with antidepressants in 50.7% of patients, with similar frequency for tricyclic antidepressants (45%) versus selective serotonin reuptake inhibitors (38.5%). Positive predictors of antidepressant-associated MxD were bipolar disorder type II diagnosis, higher index depression severity, and higher age at index episode. Antipsychotic or no treatment was protective against antidepressant-associated MxD.

CONCLUSIONS

MxD, defined as depression with excitatory symptoms, can be clinically identified, is common, occurs in both unipolar depression and bipolar disorder, and is frequently associated with antidepressant use. If replicated, this view of MxD could be considered a valid alternative to the DSM-5 criteria for depression with mixed features.

The bipolar spectrum: conceptions and misconceptions

OBJECTIVE

This review aims to address concerns about the potential overinclusiveness and vagueness of bipolar spectrum concepts, and also, concerns about the overlap between bipolar illness and borderline personality.

METHOD

Narrative review based on historical and empirical studies.

RESULTS

Bipolar disorder (BD) and major depressive disorder (MDD) came to be separate entities with the Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM III), in contrast to the Kraepelinian manic-depressive insanity (MDI) concept, which included both. The bipolar spectrum concept is a return to this earlier Kraepelinian perspective. Further, very different features differentiate the disease of bipolar illness (family history of bipolar illness, severe recurrent mood episodes with psychomotor activation) from the clinical picture of borderline personality (dissociative symptoms, sexual trauma, parasuicidal self-harm). The term 'disorder' obfuscates an ontological difference between diseases, such as manic-depressive illness, and clinical pictures, such as hysteria/post-traumatic stress disorder/dissociation/borderline personality.

CONCLUSIONS

Bipolar spectrum concepts are historically rooted in Kraepelin's manic-depressive illness concept, are scientifically testable, and can be clearly formulated. Further, they differ in kind from traumatic/dissociative conditions in ways that can be both historically and scientifically established.

Bipolar spectrum: a review of the concept and a vision for the future

This paper reviews the bipolar spectrum concept historically and empirically. It describes how the concept derives from Kraepelin, but was lost with DSM-III, which divided the broad manic-depressive illness concept, based on recurrent mood episodes of either polarity, to the bipolar versus unipolar dichotomy, based on allowing non-recurrent mood episodes of only one polarity. This approach followed the views of Karl Leonhard and other critics of Kraepelin. Thus post DSM-III American psychiatry is not neo-Kraepelinian, as many claim, but neo-Leonhardian. The bipolar spectrum approach, as advocated by Akiskal and Koukopoulos first, harkens back to the original broad Kraepelinian view of manic-depressive illness. The evidence for and against this approach is discussed, and common misconceptions, including mistaken claims that borderline personality is similar, are revealed and critiqued.

Defining bipolar mood states with quantitative measurement of inhibition/activation and emotional reactivity

OBJECTIVES

Mood state heterogeneity in bipolar disorder leads to confusion in diagnosis and therapeutic strategies. Recently, the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) showed that two-thirds of bipolar-depressed patients had concomitant manic symptoms, these characteristics being linked to a more severe form of bipolar disorder. Moreover, manic symptoms occurring during bipolar depression are associated with mood switches induced by antidepressant. It is thus important to best characterize mood episodes with mixed features in order to improve our understanding of the etiopathology and to choose the most appropriate treatment. As dimensional approach can better describe phenomena that are distributed continuously without clear boundaries, we used the MATHYS scale, constructed on a dimensional approach. The aim of the study is to determine whether two dimensions (activation/inhibition and emotional reactivity) improve assessment of bipolar states in which both manic and depressive symptoms are associated.

METHODS

We included 189 bipolar patients and 90 controls. Bipolar patients were distinguished between those with a major depressive episode without manic symptoms, a major depressive episode with manic symptoms, a mixed state and a manic state. The MATHYS scale provides a total score, quantifying an inhibition/activation process, and a score for emotional reactivity (intensity of emotions).

RESULTS

We demonstrated that there is a continuum ranging from inhibition to activation (respectively from major depressive episodes without manic symptoms to manic states), with a gradual increase in the severity of the activation. Regarding emotional reactivity, results are quiet different since only major depressive episodes without manic symptoms are characterized by emotional hypo-reactivity while major depressive episodes with manic symptoms, manic and mixed states exhibited emotional hyper-reactivity.

CONCLUSIONS

The MATHYS scale, providing a score for inhibition/activation process and a score for emotional reactivity, is clearly useful to distinguish bipolar depressive episodes without manic symptoms from those with manic symptoms. This last type of depression appears to belong to a broad spectrum of mixed state. To go further we need to explore if these two types of depression are underlined by different mechanisms and what is the most appropriate treatment for each of them.

New ways to classify bipolar disorders: going from categorical groups to symptom clusters or dimensions

Current psychiatric disorder classifications are based exclusively on categorical models, which were designed to increase the reliability of diagnoses. However, this system has some limitations, and various psychiatric disorders may be classified using a dimensional approach, which is more appropriate when no clear boundaries exist between entities or when examining various features on a continuum. Thus, the forthcoming DSM-5 appears to be undertaking a hybrid approach by including categorical models associated with dimensions. We aim to review examples of dimensions or symptom clusters associated with a categorical approach that could be useful in refining bipolar disorder classification. We selected predominant polarity, psychotic symptoms, inhibition/activation behavioral level, and emotional reactivity to define mood episodes, impulsivity/suicidality/substance misuse, and cognitive impairment. The selection was based on the fact that these dimensions or symptom clusters are currently being discussed to be implemented in the DSM-5 and/or may orientate toward the choice of specific treatments and represent more homogeneous and thus more appropriate subgroups for research purposes. In the future, there will be a need to identify biomarkers that can definitively validate the use of these criteria.

[Severe depression : specific features of bipolar disorder]

Bipolar depressions can present all the clinical aspects from a major depressive episode with a mild intensity to severe one. However, part of this severity comes from the bipolarity by itself. Bipolar disorders belong to the 10 most disabling conditions in the world. Moreover, the complexity of bipolar depressions comes also from the complexity to treat them. Antidepressants are difficult to use in bipolar subjects because the risk of switch, the possible induction of rapid cycles or of a chronic dysphoric state. Currently, guidelines are not very helpful for the choice of the treatment in case of an acute major depressive disorder. Indeed, the current guidelines give the choice between a mood stabilizer alone or associated with an antidepressant, either between an antipsychotic more or less associated with an antidepressant. A better understanding of the clinical heterogeneity of bipolar depression could help to solve a part of this complexity.

Towards a reconceptualization of mixed states, based on an emotional-reactivity dimensional model

BACKGROUND

DSM-IV criteria for mixed states may be too restrictive and may actually exclude patients who do not meet the full criteria for a manic and depressive state. Using this DSM-IV definition, many patients who are considered depressed may have mixed features, which can explain why some bipolar depressive states can worsen with antidepressants and can be improved by mood stabilizers or atypical antipsychotics. A dimensional approach not exclusively focused on the tonality of affect would help to define a broader entity of mixed states. The aim of this study was to apply a dimensional model to bipolar episodes and to assess the overlap between the groups defined using this model and using categorical diagnosis.

METHOD

We assessed 139 DSM-IV acutely ill bipolar I patients with MAThyS (Multidimensional Assessment of Thymic States by Henry et al. in press), a scale that assesses five quantitative dimensions exploring excitatory and inhibition processes, and that is not focused on tonality of mood but on emotional reactivity. We studied the relationship between clusters defined by statistical analyses and DSM-IV bipolar mood states.

RESULTS

This study showed the existence of three clusters. Cluster 1 was characterized by an inhibition in all dimensions and corresponded to the depressive cluster (more than 90% of patients met the criteria for DSM-IV Major Depressive Episode (MDE)). Cluster 2 showed a general excitation and was mainly DSM-IV manic or hypomanic patients (90%). Cluster 3 (Mixed) was more complex and the diagnosis included MDE (56%) in most of the cases associated with manic or hypomanic symptoms, mixed states (18%) defined by DSM-IV criteria, and manic or hypomanic states (25%). Emotional reactivity was relevant to distinguish Cluster 1 (Depressive), exhibiting emotional hypo-reactivity, from Cluster 2 (Manic) and 3 (Mixed), characterized by emotional hyper-reactivity. Sadness was reported equally in all three clusters.

CONCLUSION

A dimensional approach using the concept of emotional reactivity seems appropriate to define a broad mixed state entity in patients who would be diagnosed with MDE according to DSM-IV. Further studies are needed to test the relevance of this model in therapeutic strategies.

Family history validation of a definition of mixed depression

PURPOSE

The study aim was to test different definitions of mixed depression, defined as a depression with concurrent hypomanic symptoms.

METHODS

Consecutive 245 non-tertiary care outpatients with bipolar II disorder (BP-II) and 189 non-tertiary care outpatients with major depressive disorder (MDD) were interviewed (off psychoactive drugs) using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I Disorders-Clinician Version, Hypomania Interview Guide (HIG), and Family History Screen when presenting for major depressive episode (MDE) treatment. Intra-MDE hypomanic symptoms were systematically assessed. Mixed depression was defined as an MDE with concurrent hypomanic symptoms. Receiver operating characteristic (ROC) analysis and multivariate analysis were used to test different definitions of mixed depression (dimensional and categorical ones). Factor analysis was also used. Bipolar family history was the validator.

FINDINGS

Bipolar II disorder, vs MDD, had significantly more intra-MDE hypomanic symptoms (racing/crowded thoughts, irritable mood, psychomotor agitation, more talkativeness, and increased goal-directed and risky activities). Major depressive episode plus 3 or more hypomanic symptoms was present in 68.7% of BP-II and 42.3% of MDD. A "motor activation" factor, including psychomotor agitation and talkativeness, and a "mental activation" factor including racing/crowded thoughts were found. Different definitions (dimensional and categorical ones) of mixed depression were tested vs bipolar family history as validator (ie, MDE plus more than 1, 2, 3, and 4 concurrent hypomanic symptoms, MDE plus psychomotor agitation, MDE plus racing thoughts). Major depressive episode plus more than 1 hypomanic symptom had the highest sensitivity but the lowest specificity. Instead, MDE plus more than 4 hypomanic symptoms had the lowest sensitivity and the highest specificity. The better-balanced combination of sensitivity and specificity was shown by MDE plus more than 2 hypomanic symptoms. The same definition also showed the highest ROC area value. Multivariate regression of bipolar family history vs different mixed depression definitions found that the only strong and significant predictor was MDE plus more than 2 hypomanic symptoms. A dose-response relationship was found between the number of hypomanic symptoms during MDE and the bipolar family history loading.

CONCLUSIONS

Mixed depression (MDE plus 3 or more hypomanic symptoms) was common in BP-II and MDD. A dimensional definition based on 3 or more hypomanic symptoms during depression was the most supported by using bipolar family history as validator. The study of mixed depression may be important for its possible impact on treatment (antidepressants could increase hypomanic symptoms, and mood stabilizers and antipsychotics could control hypomanic symptoms during antidepressant treatment).

Mixed depressive states: nosologic and therapeutic issues

This paper focuses on the clinical importance of affective mixed states with special attention given to agitated depression, which has lost its status as a mixed state in the DSM and ICD systems. Following a historical review of the topic, the psychopathological elements are examined. Psychic and motor agitation are considered equally important for the definition of agitated depression and the concept of latent agitated depression is introduced for those major depressive episodes that become agitated following antidepressant treatment. The thesis is advanced that the erroneous nosologic position of agitated depression and its treatment as simple, unipolar depression is at least partly responsible for the problematic issues of the unfavourable treatment outcome and high suicide rates among depressive patients.

Absence of gender differences in pediatric bipolar disorder: findings from a large sample of referred youth

BACKGROUND

Because little is known about gender differences in pediatric bipolar disorder, we evaluated whether gender moderates the expression of pediatric bipolar disorder in a large clinical sample.

METHODS

Subjects were consecutively referred youth aged 18 years or less who met full criteria for DSM-III-R bipolar disorder (BPD) (females, n=74; BD males, n=224). All subjects were assessed with a structured diagnostic interview and measures of psychosocial and family functioning.

RESULTS

Most of the bipolar subjects (91% of males, 70% of females) also had ADHD. Bipolar disorder was equally prevalent in both genders. Among females and males, severe irritability (83% and 80%, respectively), mixed presentation (87% and 84%, respectively), chronic course (84% and 77%, respectively) and prepubertal onset (78% and 93%, respectively) predominated the clinical picture. We found no meaningful differences between genders in the number of BPD symptoms, type of treatment for BPD (counseling, medication, hospitalization), severity of educational deficits, severity of family and interpersonal functioning or patterns of psychiatric comorbidity.

CONCLUSIONS

Because gender does not moderate the clinical expression of pediatric bipolar disorder, our data does not suggest that gender specific criteria for the disorder are warranted.