Bipolar family history of the hypomanic symptoms and dimensions of mixed 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.

Reviewing the diagnostic validity and utility of mixed depression (depressive mixed states)

Objective

To review the diagnostic validity and utility of mixed depression, i.e. co-occurrence of depression and manic/hypomanic symptoms.

Methods

PubMed search of all English-language papers published between January 1966 and December 2006 using and cross-listing key words: bipolar disorder, mixed states, criteria, utility, validation, gender, temperament, depression-mixed states, mixed depression, depressive mixed state/s, dysphoric hypomania, mixed hypomania, mixed/dysphoric mania, agitated depression, anxiety disorders, neuroimaging, pathophysiology, and genetics. A manual review of paper reference lists was also conducted.

Results

By classic diagnostic validators, the diagnostic validity of categorically-defined mixed depression (i.e. at least 2–3 manic/hypomanic symptoms) is mainly supported by family history (the current strongest diagnostic validator). Its diagnostic utility is supported by treatment response (negative effects of antidepressants). A dimensionally-defined mixed depression is instead supported by a non-bi-modal distribution of its intradepression manic/hypomanic symptoms.

Discussion

Categorically-defined mixed depression may have some diagnostic validity (family history is the current strongest validator). Its diagnostic utility seems supported by treatment response.

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.

Suicide attempts in major depressive episode: evidence from the BRIDGE-II-Mix study

OBJECTIVES

The Bipolar Disorders: Improving Diagnosis, Guidance, and Education (BRIDGE-II-Mix) study aimed to estimate the frequency of mixed states in patients with a major depressive episode (MDE) according to different definitions and to compare their clinical validity, looking into specific features such as suicidality.

METHODS

A total of 2,811 subjects were enrolled in this multicenter cross-sectional study. Psychiatric symptoms, and sociodemographic and clinical variables were collected. The analysis compared the characteristics of patients with MDE with (MDE-SA group) and without (MDE-NSA) a history of suicide attempts.

RESULTS

The history of suicide attempts was registered in 628 patients (22.34%). In the MDE-SA group, women (72.5%, p = 0.028), (hypo)mania in first-degree relatives (20.5%, p < 0.0001), psychotic features (15.1%, p < 0.0001), and atypical features (9.2%, p = 0.009) were more prevalent. MDE-SA patients' previous responses to treatment with antidepressants included more (hypo)manic switches [odds ratio (OR) = 1.97, 95% confidence interval (CI): 1.58-2.44, p < 0.0001], treatment resistance (OR = 2.07, 95% CI: 1.72-2.49, p < 0.0001), mood lability (OR = 1.98, 95% CI: 1.65-2.39, p < 0.0001), and irritability (OR = 1.80, 95% CI: 1.48-2.17, p < 0.0001). Multivariate analysis evidenced that risky behavior, psychomotor agitation and impulsivity, and borderline personality and substance use disorders were the variables most frequently associated with previous suicide attempts. In the MDE-SA group, 75 patients (11.9%) fulfilled Diagnostic and Statistical Manual (DSM)-5 criteria for MDE with mixed features, and 250 patients (39.8%) fulfilled research-based diagnostic criteria for a mixed depressive episode.

CONCLUSIONS

Important differences between MDE-SA and MDE-NSA patients have emerged. Early identification of symptoms such as risky behavior, psychomotor agitation, and impulsivity in patients with MDE, and treatment of mixed depressive states could represent a major step in suicide prevention.

Early risk factors for adult bipolar disorder in adolescents with mood disorders: a 15-year follow-up of a community sample

BACKGROUND

We aimed to outline the early risk factors for adult bipolar disorder (BPD) in adolescents with mood disorders.

METHODS

Adolescents (16-17 years old) with mood disorders (n = 287; 90 participants with hypomania spectrum episodes and 197 with major depressive disorder [MDD]) were identified from a community sample. Fifteen years later (at 30-33 years of age), mood episodes were assessed (n = 194). The risk of developing BPD (n = 22), compared with MDD (n = 104) or no mood episodes in adulthood (n = 68), was estimated via logistic regression. Adolescent mood symptoms, non-mood disorders, and family characteristics were assessed as potential risk factors.

RESULTS

Among the adolescents with mood disorders, a family history of BPD was the strongest predictor of developing BPD compared with having no mood episodes in adulthood (OR = 5.94; 95% CI = 1.11-31.73), whereas disruptive disorders significantly increased the risk of developing BPD compared with developing MDD (OR = 2.94; CI = 1.06-8.12). The risk that adolescents with MDD would develop adult BPD, versus having no mood episodes in adulthood, was elevated among those with an early disruptive disorder (OR = 3.62; CI = 1.09-12.07) or multiple somatic symptoms (OR = 6.60; CI = 1.70-25.67). Only disruptive disorders significantly predicted adult BPD among adolescents with MDD versus continued MDD in adulthood (OR = 3.59; CI = 1.17-10.97). Only a few adolescents with hypomania spectrum episodes continued to have BPD as adults, and anxiety disorders appeared to increase this risk.

CONCLUSIONS

Although most of the identified potential risk factors are likely general predictors of continued mood disorders, disruptive disorders emerged as specific predictors of developing adult BPD among adolescents with MDD.

Activated depression: mixed bipolar disorder or agitated unipolar depression?

The combination of depression and activation presents clinical and diagnostic challenges. It can occur, in either bipolar disorder or major depressive disorder, as increased agitation as a dimension of depression. What is called agitation can consist of expressions of painful inner tension or as disinhibited goal-directed behavior and thought. In bipolar disorder, elements of depression can be combined with those of mania. In this case, the agitation, in addition to increased motor activity and painful inner tension, must include symptoms of mania that are related to goal-directed behavior or manic cognition. These diagnostic considerations are important, as activated depression potentially carries increased behavioral risk, especially for suicidal behavior, and optimal treatments for depressive episodes differ between bipolar disorder and major depressive disorder.

Depression across mood disorders: review and analysis in a clinical sample

OBJECTIVES

In this article we aimed to: (1) review literature concerning the clinical and psychopathologic characteristics of Bipolar (BP) depression; (2) analyze an independent sample of depressed patients to identify any demographic and/or clinical feature that may help in differentiating mood disorder subtypes, with special attention to potential markers of bipolarity.

METHODS

A sample of 291 depressed subjects, including BP -I (n = 104), BP -II (n = 64), and unipolar (UP) subjects with (n = 53) and without (n = 70) BP family history (BPFH), was examined to evidence potential differences in clinical presentation and to validate literature-derived markers of bipolarity. Demographic and clinical variables and, also, single items from the Hamilton Depression Rating Scale (HDRS), the Montgomery-Asberg Depression Rating Scale (MADRS), and the Young Mania Rating Scale (YMRS) were compared among groups.

RESULTS

UP subjects had an older age at onset of mood symptoms. A higher number of major depressive episodes and a higher incidence of lifetime psychotic features were found in BP subjects. Items expressing depressed mood, depressive anhedonia, pessimistic thoughts, and neurovegetative symptoms of depression scored higher in UP, whereas depersonalization and paranoid symptoms' scores were higher in BP. When compared with UP, BP I had a significantly higher incidence of intradepressive hypomanic symptoms. Bipolar family history was found to be the strongest predictor of bipolarity in depression.

CONCLUSIONS

Overall, our findings confirm most of the classical signs of bipolarity in depression and support the view that some features, such as BPFH, together with some specific symptoms may help in detecting depressed subjects at higher risk for BP disorder.

Prevalence and correlates of bipolar II disorder in major depressive patients at a psychiatric outpatient clinic in Hong Kong

BACKGROUND

Western studies indicate a high prevalence of bipolar II disorder defined by a Research Diagnostic Criteria 2-day hypomania duration criterion (30 to 61%) amongst clinically depressive patients. The situation in Chinese patients with depression is unknown.

METHODS

64 (52.5% response rate) patients first presenting to a Hong Kong public psychiatric outpatient clinic in 2005 with a diagnosis of major depression were recruited. The SCID and Family History Screen were administered.

RESULTS

DSM-IV bipolar II was found in 20.5% of depressive outpatients; 35.9% had bipolar II disorder defined by RDC 2-day duration criterion for hypomania. Family bipolarity, age of onset, and depressive recurrence distinguished bipolar II subjects from unipolar depressives irrespective of duration criteria chosen for hypomania.

LIMITATIONS

Sample size was limited.

CONCLUSIONS

Bipolar II disorder is common amongst Chinese depressive outpatients. The evaluation method and 2-day duration criterion for hypomania were supported by bipolar validators. Replication using larger samples is needed to arrive at a more representative prevalence estimate and to enable more refined nosological evaluation.

Characterizing major depression phenotypes by presence and type of psychomotor disturbance in adolescents and young adults

Major depressive disorder (MDD) is phenomenologically heterogeneous, which has prompted investigation of intermediate MDD phenotypes based on specific key symptoms. Presence and type of psychomotor disturbance may be an important psychopathologic feature that differentiates clinically distinct forms of juvenile MDD. This study examined the phenotypic status of three putative MDD phenotypes in a community sample of 941 youths: (1) agitated depression (MDD with psychomotor agitation), (2) retarded depression (MDD with psychomotor retardation), and (3) agitated-retarded depression (MDD with psychomotor agitation and retardation within an episode). Hasler et al.'s [2004: Neuropsychopharmacology 29:1765-1781] criteria of specificity (degree of association with relevant symptoms and conditions related to the disease of interest versus other psychiatric conditions), stability (degree of stability over time), and heritability (degree of familial aggregation with relevant conditions) were used to evaluate the phenotypic significance of these subtypes. Results were suggestive that agitated depression was a relatively specific phenotypic syndrome characterized by irritability, arousal, physical complaints, and vulnerability to anxiety disorders and alcohol dependence; low stability across depressive episodes; and low heritability. Agitated-retarded depression was relatively specific and characterized by increased severity, recurrence, vegetative symptoms, suicidal ideation, social impairment, endogeneity, and vulnerability to anxiety disorders and bulimia; low stability across episodes; and modest heritability. Although retarded depression was associated with some specific distinguishing characteristics, most associations were explained by the increased severity of this phenotype. Retarded depression evidenced little stability or heritability. These findings offer partial support of the phenotypic status of agitated and agitated-retarded depression in youths.

Impact of depressive mixed state in an emergency psychiatry setting: a marker of bipolar disorder and a possible risk factor for emergency hospitalization

BACKGROUND

Depressive mixed state (DMX) has been reported to be one of the most useful clinical markers for bipolar II disorder (BP-II) in the outpatient setting. However, the significance of DMX in emergency psychiatry has not been well studied.

METHODS

A chart review study of 139 patients who were hospitalized in an emergency psychiatric ward with an initial diagnosis of major depressive disorder (MDD).

RESULTS

In 42 (30.2%) patients, the diagnosis was changed to bipolar disorder after a median observation period of 189 days from hospitalization, and of these, 34 were diagnosed as having BP-II. DMX was observed in 56 (40.3%) patients at the time of hospitalization. Compared with patients who remained in MDD, significantly more patients who later developed bipolar disorder had experienced DMX (59.5% vs. 32.0%, p = 0.0044). In multivariate analysis, DMX was one of the independent predictors of conversion to bipolar disorder (OR 2.45, p = 0.037), and the independent predictors for DMX were chronic depression and atypical features (OR 2.85, p = 0.010; OR 3.67, p = 0.046, respectively). In addition, DMX was significantly more frequently observed at emergency hospitalization than at non-emergency hospitalization (48.6% vs. 29.1%, p = 0.0065).

LIMITATIONS

A single reviewer evaluated DMX by chart review.

CONCLUSION

DMX is a useful marker of bipolar disorder (mainly BP-II) in the emergency psychiatric setting and is closely related to emergency hospitalization for mood disorders. To confirm these findings, a prospective study that systematically evaluates DMX is needed.

Associations between depression subtypes and substance use disorders

Evaluating whether certain subtypes of Major Depressive Disorder (MDD) are more strongly associated with Substance Use Disorders (SUDs) may help clarify reasons for MDD-SUD relations. Therefore, this study compared DSM-IV-defined non-atypical/non-melancholic depression (undifferentiated depression; n=365), atypical depression (n=117), melancholic depression (n=245), and atypical-melancholic depression (n=68) in the prevalence of current SUDs, while controlling for relevant demographic and clinical variables. Psychiatric outpatients with a current diagnosis of unipolar MDD were assessed using the Structured Clinical Interview for DSM-IV, supplemented by questions from the Schedule for Affective Disorders and Schizophrenia. Results showed that compared with patients with undifferentiated depression, melancholic patients had higher rates of current nicotine dependence (34% vs. 26%) and drug abuse/dependence (8% vs. 3%), Ps<0.05. These differences were explained by the association between specific melancholic features (marked psychomotor agitation and weight loss/decreased appetite) and nicotine and drug use disorders. Atypical depression, atypical-melancholic depression, and other subtype symptoms were not significantly associated with any SUDs. Although this study is limited by low prevalence of alcohol and drug use disorders, the present findings suggest that different symptomatic expressions of MDD differentially associate with some SUDs.

Validity and utility of bipolar spectrum models

The bipolar spectrum model suggests that several patient presentations not currently recognized by the DSM warrant consideration as part of a mood disorders continuum. These include hypomania or mania associated with antidepressants; manic symptoms which fall short of the current DSM threshold for hypomania; and depression attended by multiple non-manic markers that are associated with bipolar course. Evidence supporting the inclusion of these groups within the realm of bipolar disorder (BP) is examined. Several diagnostic tools for detecting and characterizing these patient groups are described. Finally, options for altering DSM-IV criteria to allow some of the above patient presentations to be recognized as bipolar are considered. More data on the validity and utility of these alterations would be useful, but limited changes appear warranted now. We describe an additional BP Not Otherwise Specified (BP NOS) example which creates a subthreshold hypomanic analogue to cyclothymia, consistent with existing BP NOS criteria. This change should be accompanied by additional requirements for the assessment and reporting of non-manic bipolar markers.

Frequency of dysphoria and mixed states

BACKGROUND

Mixed states are a complex entity in the field of mood disorders. Dysphoria has been advocated as an important clinical dimension of mixed states. The objective of this work is to study the frequency of dysphoria within a population of patients with DSM-IV major depressive and/or manic episodes and to determine if it may help establish diagnostic criteria for subthreshold cases of depressive or manic mixed states.

SAMPLING AND METHODS

A total of 165 patients were assessed using the Mini International Neuropsychiatric Interview complemented by a section defining dysphoria as a constellation of 3 among 4 symptoms (inner tension, irritability, aggressive behavior and hostility).

RESULTS

When classifying patients according to the number of symptoms of the opposite polarity, changes in the frequency of dysphoria revealed a clear contrast between the 2 opposite manic and depressive poles and the full mixed state (DSM-IV definition). The frequency of dysphoria was 17.5% in pure depression, 22.7% in pure mania and 73.3% in full mixed state. Two threshold effects were identified: (1) the frequency of dysphoria increased from 17.5 to 61.1% (p = 0.002) when the number of manic symptoms in DSM-IV depressed patients increased from 0 to 1, and (2) dysphoria increased from 14.3 to 69.2% (p = 0.057) when the number of depressive symptoms increased from 2 to 3 in DSM-IV manic patients.

CONCLUSION

Dysphoria is strongly but not necessarily associated with mixed states. When used as a clinical marker for mixed states, dysphoria confirms the modern delimitations of sub-threshold mixed states by specifying the required number of symptoms of the opposite polarity (which could be lower for depressive mixed states than for manic mixed states). The study has limitations related to the inclusion of patients who are not drug-free, to the definition of dysphoria and to the sample size.

Bipolar II disorder : epidemiology, diagnosis and management

Bipolar II disorder (BP-II) is defined, by DSM-IV, as recurrent episodes of depression and hypomania. Hypomania, according to DSM-IV, requires elevated (euphoric) and/or irritable mood, plus at least three of the following symptoms (four if mood is only irritable): grandiosity, decreased need for sleep, increased talking, racing thoughts, distractibility, overactivity (an increase in goal-directed activity), psychomotor agitation and excessive involvement in risky activities. This observable change in functioning should not be severe enough to cause marked impairment of social or occupational functioning, or to require hospitalisation. The distinction between BP-II and bipolar I disorder (BP-I) is not clearcut. The symptoms of mania (defining BP-I) and hypomania (defining BP-II) are the same, apart from the presence of psychosis in mania, and the distinction is based on the presence of marked impairment associated with mania, i.e. mania is more severe and may require hospitalisation. This is an unclear boundary that can lead to misclassification; however, the fact that hypomania often increases functioning makes the distinction between mania and hypomania clearer. BP-II depression can be syndromal and subsyndromal, and it is the prominent feature of BP-II. It is often a mixed depression, i.e. it has concurrent, usually subsyndromal, hypomanic symptoms. It is the depression that usually leads the patient to seek treatment.DSM-IV bipolar disorders (BP-I, BP-II, cyclothymic disorder and bipolar disorder not otherwise classified, which includes very rapid cycling and recurrent hypomania) are now considered to be part of the 'bipolar spectrum'. This is not included in DSM-IV, but is thought to also include antidepressant/substance-associated hypomania, cyclothymic temperament (a trait of highly unstable mood, thinking and behaviour), unipolar mixed depression and highly recurrent unipolar depression.BP-II is underdiagnosed in clinical practice, and its pharmacological treatment is understudied. Underdiagnosis is demonstrated by recent epidemiological studies. While, in DSM-IV, BP-II is reported to have a lifetime community prevalence of 0.5%, epidemiological studies have instead found that it has a lifetime community prevalence (including the bipolar spectrum) of around 5%. In depressed outpatients, one in two may have BP-II. The recent increased diagnosing of BP-II in research settings is related to several factors, including the introduction of the use of semi-structured interviews by trained research clinicians, a relaxation of diagnostic criteria such that the minimum duration of hypomania is now less than the 4 days stipulated by DSM-IV, and a probing for a history of hypomania focused more on overactivity (increased goal-directed activity) than on mood change (although this is still required for a diagnosis of hypomania). Guidelines on the treatment of BP-II are mainly consensus based and tend to follow those for the treatment of BP-I, because there have been few controlled studies of the treatment of BP-II. The current, limited evidence supports the following lines of treatment for BP-II. Hypomania is likely to respond to the same agents useful for mania, i.e. mood-stabilising agents such as lithium and valproate, and the second-generation antipsychotics (i.e. olanzapine, quetiapine, risperidone, ziprasidone, aripiprazole). Hypomania should be treated even if associated with overfunctioning, because a depression often soon follows hypomania (the hypomania-depression cycle). For the treatment of acute BP-II depression, two controlled studies of quetiapine have not found clearcut positive effects. Naturalistic studies, although open to several biases, have found antidepressants in acute BP-II depression to be as effective as in unipolar depression; however, one recent large controlled study (mainly in patients with BP-I) has found antidepressants to be no more effective than placebo. Results from naturalistic studies and clinical observations on mixed depression, while in need of replication in controlled studies, indicate that antidepressants may worsen the concurrent intradepression hypomanic symptoms. The only preventive treatment for both depression and hypomania that is supported by several, albeit older, controlled studies is lithium. Lamotrigine has shown some efficacy in delaying depression recurrences, but there have also been several negative unpublished studies of the drug in this indication.

Is there a continuity between bipolar and depressive disorders?

BACKGROUND

Recent studies questioned the current categorical split of mood disorders into bipolar disorders (BP) and depressive disorders (MDD).

METHODS

Medline database search of papers from the last 10 years on the categorical-dimensional classification of mood disorders. Various combinations of the following key words were used: mood disorders, bipolar, unipolar, major depressive disorder, spectrum, category/categorical, classification, continuity. Only English language clinical papers were included, review papers were excluded, similar papers selected by quality. The number of papers found was 1,141. The number of papers selected was 109.

RESULTS

The continuity/spectrum between BP (mainly BP-II) and MDD was supported by the following findings:(1) high frequency of mixed states (mixed mania, mixed hypomania, mixed depression, i.e. co-occurring depression and noneuphoric manic/hypomanic symptoms) because opposite polarity symptoms in the same episode do not support a hypomania/mania-depression splitting; (2) MDD was the most common mood disorder in BP probands' relatives; (3) no bimodal distribution of distinguishing symptoms between BP and MDD; (4) bipolar signs not uncommon in MDD; (5) many MDD shifting to BP; (6) many lifetime manic/hypomanic symptoms in MDD; (7) correlation between lifetime manic/hypomanic symptoms and MDD symptoms; (8) hypomania factors in MDD; (9) MDD often recurrent; (10) similar cognitive style. The categorical distinction between BP (mainly BP-I) and MDD was supported by the following findings: (1) BP more common in BP probands' relatives; (2) lower age at BP onset; (3) females as common as males in BP-I, more common than males in MDD; (4) BP-I depression more atypical and retarded, MDD depression more sleepless and agitated; (5) BP more recurrent.

CONCLUSIONS

Focusing on mood spectrum's extremes (BP-I vs. MDD), a categorical distinction seems supported. Focusing on midway disorders (BP-II and MDD plus bipolar signs), a continuity/spectrum seems supported. Results seem to support both a categorical and a dimensional view of mood disorders.

Bipolar disorder--focus on bipolar II disorder and mixed depression

Bipolar II disorder (recurrent depressive and hypomanic episodes) and related disorders (united in the bipolar spectrum) are understudied, despite a prevalence of about 5% in the community and about 50% in depressed outpatients. The apparent increase in prevalence of the bipolar spectrum is related to several changes in diagnostic criteria, including improved probing for history of hypomania (focused more on overactivity than on mood change), lower minimum duration of hypomania, and inclusion of unipolar depressions with bipolar signs (eg, family history of bipolar disorder, mixed depression). Prevalence of mixed depression, a combination of depression and manic or hypomanic symptoms, is high in patients with bipolar disorders. Controlled studies are needed to investigate treatment of mixed depression; antidepressants can worsen manic and hypomanic symptoms, and mood stabilising agents might be necessary.