Clinical characteristics of unipolar disorder and bipolar disorder according to the lifetime presence of recurrent panic attacks

Objectives:  The frequent comorbidity of panic and affective disorders has been described in previous studies. However, it is not clear how panic disorder comorbidity in unipolar disorder and bipolar disorder is related to illness course.
Methods:  We compared lifetime clinical characteristics of illness and items of symptomatology in samples of individuals with bipolar I disorder (n = 290) and unipolar disorder (n = 335) according to the lifetime presence of recurrent panic attacks.
Results:  We found significant differences in clinical course of illness characteristics that were shared across the unipolar and bipolar samples according to the lifetime presence of panic attacks. We also found a number of differences according to the presence of panic attacks that may be specific to the diagnostic group.
Conclusions:  Distinguishing patients who have mood disorder diagnoses, especially bipolar I disorder, according to the lifetime presence of panic attacks may not only be of use in clinical practice, but may also be informative for aetiological research, such as molecular genetic studies.     

Rapid switching of mood in families with familial bipolar disorder

Objective:  Rapid switching of moods in bipolar disorder has been associated with early age at onset, panic comorbidity, and suicidality. This study aims to confirm these associations and investigate other potential correlates of rapid switching of mood using families from a multisite bipolar linkage study.
Methods:  The subjects were comprised of 1,143 probands and relatives with diagnosis of bipolar disorder. All subjects were interviewed directly with a standard diagnostic instrument, and all subjects who met criteria for bipolar disorder were asked if their moods had ever switched rapidly.
Results:  Individuals with rapid mood switching had significantly earlier age at onset (18 versus 21 years, p < 0.00001), higher comorbid anxiety (47% versus 26%, p < 0.00001) and substance use disorders (52% versus 42%, p = 0.0006), higher rate of violent behavior (6% versus 3%, p < 0.004), suicidal behavior (46% versus 31%, p < 0.00001), and nonsuicidal self-harm (13% versus 6%, p < 0.0002). Multiple logistic regression analysis found significant net effects on rapid mood switching for early emergence of symptoms [odds ratio (OR) = 0.62; 95% confidence interval (CI): 0.45–0.85]; anxiety comorbidity (OR = 2.31; 95% CI: 1.34–3.98); and hypersensitivity to antidepressants (OR = 2.05; 95% CI: 1.49–2.83) as the strongest predictors.
Conclusions:  This confirms earlier reports associating rapid switching with a more complex clinical course, in particular early emergence of bipolar symptomatology, antidepressant activation, and anxiety comorbidity. These results support a clinical differentiation of bipolar disorder into subtypes based on symptom stability.     

Comorbid bipolar disorder and panic disorder in families with a high prevalence of bipolar disorder.

OBJECTIVE: Panic attacks are a common complication of affective disorder, although the etiologic relationship of panic and affective symptoms has not been determined. Evidence from a family study suggests that panic attacks and panic disorder may be related genetically to bipolar disorder. This study used diagnostic data from the NIMH Bipolar Disorder Genetics Initiative to assess in a separate, larger family set the familiality of panic combined with bipolar disorder. METHOD: First-degree relatives (N=966) of probands with bipolar I disorder (N=192) and schizoaffective disorder, bipolar type, (N=11) were included in the study. All subjects were interviewed directly and were assigned best-estimate diagnoses for major affective and other psychiatric disorders. The risk of a family member being diagnosed with panic disorder if the proband with bipolar disorder had panic attacks or panic disorder was calculated with logistic regression analysis with generalized estimating equations that controlled for sex and affective disorder subdiagnosis. RESULTS: More than 90% of the probands and first-degree relatives with panic disorder also had an affective disorder diagnosis. Panic disorder was present in 17% of the relatives with recurrent major affective disorder and in 3% of the relatives without recurrent major affective disorder. Risk of panic disorder in relatives with bipolar disorder was increased significantly if the proband had panic attacks or panic disorder. CONCLUSIONS: Risk for panic disorder with familial bipolar disorder appears to be inherited. Inherited risk for panic disorder with bipolar disorder may indicate a shared genetic etiology for both disorders in some families. The patterns of bipolar disorder and panic disorder comorbidity observed in families imply a complex genetic etiology, which may be elucidated by using endophenotypes.     

Phenotypic spectra of bipolar disorder in responders to lithium versus lamotrigine

Objective:  We conducted a study of clinical presentation and family history in patients responsive to either of two commonly used mood stabilizers, lithium and lamotrigine.
Methods:  The sample included 164 subjects from 21 families of bipolar probands, 14 responders to lithium and seven to lamotrigine. Diagnostic information on first-degree relatives was obtained in a blind fashion through a combination of direct interviews (SADS-L) and family history assessments (FH-RDC).
Results:  The probands differed with respect to clinical course (episodic in the lithium group, rapid cycling in the lamotrigine group), and comorbidity (panic attacks and substance abuse in the lamotrigine group). The relatives of lithium responders had significantly higher risk of bipolar disorder while relatives of lamotrigine responders had higher prevalence of schizoaffective disorder, major depression and panic attacks.
Conclusions:  These findings suggest that lithium- and lamotrigine-responsive patients differ with respect to course of illness, comorbidity and family history and may represent distinct subtypes of bipolar disorder.     

Pilot sample of very early onset bipolar disorder in a military population moderates the association of negative life events and non-fatal suicide attempt

Objective:  To examine the moderating effects of very early onset diagnostic status (≤ 13 years) upon the association between life events and non-fatal suicide attempt.
Methods:  Measures of negative life events, suicidal ideation and current suicide attempt were administered to 298 military-based young adults at entry to treatment for suicidality. Current and lifetime diagnoses were assigned using the Diagnostic Interview Schedule. The predictive ability of negative life events for non-fatal suicide attempt was examined separately for the total sample and for those with retrospectively determined histories of very early onset bipolar disorder (VEOBPD; n = 16), very early onset major depressive disorder (VEOMDD; n = 21) and very early onset anxiety disorder (VEOANX; n = 53).
Results:  Negative life events and suicide attempt were significantly and positively associated among those with no history of VEOBPD (OR = 1.30, 95% CI = 1.02–1.65, p < 0.05), including those with VEOMDD and VEOANX. Consistent with expectation, VEOBPD moderated the association between negative life events and suicide attempt (OR = 0.88, 95% CI = 0.78–0.99, p < 0.05), such that negative life events were non-significantly and negatively associated with the presence of a suicide attempt (OR = 0.21, 95% CI = 0.04–1.02, p = 0.09) among patients with a history of VEOBPD.
Conclusions:  Despite similar rates of suicide attempt among all diagnostic groups, life stress did not contribute to attempt among those with VEOBPD. These findings are consistent with the severity and chronicity of VEOBPD. Potential explanations of these findings include a scarring effect on coping skills and increased sensitization to life stress.     

Severity of mood symptoms and work productivity in people treated for bipolar disorder

Objective:  To evaluate the relationship between mood symptoms and work productivity in people with bipolar disorder.
Methods:  A total of 441 outpatients treated for bipolar disorder were enrolled from mental health clinics of a health plan in Washington State. A baseline assessment included confirmation of diagnosis (using the Structured Clinical Interview for DSM-IV) as well as assessment of employment status, functional impairment, and days missed from work. Eight follow-up interviews over 24 months included self-reported employment status, self-reported days missed from work due to illness, and assessment of current and interval mood symptoms using the Longitudinal Interval Follow-up Examination.
Results:  Averaged over four assessments, patients with current major depression were 15% less likely to be employed than those without significant depressive symptoms [odds ratio (OR) = 0.84, 95% confidence interval (CI): 0.76–0.92]. Manic or hypomanic symptoms were not significantly associated with probability of employment (OR = 0.93, CI: 0.83–1.04). Among those employed, major depression was associated with 4.06 additional days of work missed per month (CI: 1.05–7.06) compared to those without significant depressive symptoms. Meeting criteria for manic or hypomanic episode was associated with a similar number of missed work days, but this difference was not statistically significant (adjusted difference = 4.11 days, CI: -0.18–8.40).
Conclusions:  Among patients with bipolar disorder, depression is strongly and consistently associated with decreased probability of employment and more days missed from work due to illness. Symptoms of mania or hypomania have more variable effects on work productivity.     

Cardiovascular disease and hypertension among adults with bipolar I disorder in the United States

Objective:  Despite ample evidence of excess cardiovascular mortality in bipolar disorder (BD), few studies have demonstrated increased prevalence of cardiovascular disease (CVD) and/or hypertension (HTN) in BD. We therefore examined this topic in a representative epidemiologic sample.
Method:  The 2001–2002 National Epidemiologic Survey on Alcohol and Related Conditions was used to determine whether prevalence of physician-diagnosed CVD and HTN is elevated among subjects with lifetime bipolar I disorder (BD-I), and whether CVD and HTN are prevalent at earlier ages among subjects with BD-I.
Results:  The age-, race-, and sex-adjusted prevalence of CVD was significantly greater among subjects with BD-I versus controls [odds ratio (OR) = 4.95, 95% confidence interval (CI): 4.27–5.75] and versus subjects with major depressive disorder [(MDD); OR =1.80, 95% CI: 1.52–2.14], as was the prevalence of HTN (OR = 2.38, 95% CI: 2.16–2.62 versus controls, OR = 1.44, 95% CI: 1.30–1.61 versus MDD; p < 0.0001 for all). Controlling additionally for marital status, education, income, obesity, smoking, anxiety disorders, and substance use disorders did not substantially alter these findings. The mean age of BD-I subjects with CVD and HTN was 14 and 13 years younger, respectively, than controls with CVD and HTN.
Conclusions:  Adults with BD-I are at increased risk of CVD and HTN, prevalent over a decade earlier than non-BD adults. Strategies are needed to prevent excessive and premature cardiovascular burden in BD-I.     

Association of rapid mood switching with panic disorder and familial panic risk in familial bipolar disorder

OBJECTIVE: Comorbid bipolar and panic disorders aggregate in families. A phenotypic trait shared by both disorders is the sudden shift in affect observed in panic attacks and some rapid cycling states. The authors investigated whether comorbidity of bipolar disorder and panic disorder is associated with rapid mood switching in families with a high rate of bipolar disorder. METHOD: Six hundred six subjects with bipolar disorder from the NIMH Bipolar Disorder Genetics Initiative were included in the study. Logistic regression analysis was used to analyze rapid mood switching as a function of panic disorder diagnosis, sex, and familial risk for panic. RESULTS: Familial panic and the diagnosis of panic disorder in an individual subject increased the odds for rapid mood switching. The familial effect persisted when individuals with panic disorder were excluded from the analysis. CONCLUSIONS: Panic and rapid mood switching occurring together in familial bipolar disorder may define a useful subphenotype for future studies.     

Multiple anxiety disorder comorbidity in patients with mood spectrum disorders with psychotic features

OBJECTIVE: The authors investigated frequencies and clinical correlates of multiple associations of panic disorder, obsessive-compulsive disorder (OCD), and social phobia in patients with severe mood disorders. METHOD: Subjects were 77 consecutively hospitalized adults with psychotic symptoms and with a diagnosis of bipolar I disorder, major depression, or schizoaffective disorder, bipolar type. Principal diagnosis and comorbidity were assessed by the Structured Clinical Interview for DSM-III-R-Patient Version. RESULTS: Of the entire cohort, 33.8% had a single anxiety disorder and 14.3% had two or three comorbid diagnoses. Patients with multiple comorbidity had significantly higher scores on the Brief Psychiatric Rating Scale and SCL-90 and abused stimulants more frequently than did those without anxiety disorders. CONCLUSIONS: Multiple associations of panic disorder, OCD, and social phobia are not rare among patients with affective psychoses and are likely to be associated with more severe psychopathology than is found in patients without anxiety disorders.     

Norepinephrine and serotonin imbalance in the locus coeruleus in bipolar disorder

Objectives:  Abnormalities in norepinephrine (NE) and serotonin (5-HT) are implicated in bipolar disorder (BD). We examined 5-HT input and NE neurons in the locus coeruleus (LC, the NE nucleus that innervates the forebrain) in BD by quantifying immunoreactivity (IR) for tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), the biosynthetic enzymes for NE and 5-HT, respectively.
Methods:  Six suicides with BD were compared to matched normal controls and unipolar major depression suicides, using immunocytochemistry with computer-assisted quantification of immunoreactivity.
Results:  Depressed bipolar suicides had 26.7 ± 1.3% of LC area occupied by the TH immunoreactive (TH-IR) process, while controls had 50.7 ± 8% (p = 0.002) and unipolar depressed suicides had 50.3 ± 2.5% (p = 0.003). In bipolars, these processes did not stain as darkly (1.9 ± 0.5 × background) as controls (2.9 ± 0.9 × background; p = 0.01) or unipolars (2.9 ± 0.6 × background; p = 0.002). Bipolar suicides also had less TPH-IR processes in the LC (11.7 ± 10%) compared with controls (32.8 ± 8.8%; p = 0.01) or unipolar suicides (30.3 ± 8%; p = 0.02). The TPH-IR intensity did not differ between groups.
Conclusions:  We found less TH-IR and TPH-IR in the LC in depressed bipolar suicides, but not unipolar suicides, suggesting that both NE and 5-HT activity is lower in BD. Studies during manic or euthymic states will determine whether these changes are mood state dependent.     

Anxiety as a correlate of response to the acute treatment of bipolar I disorder

OBJECTIVE: Given the adverse impact of anxiety on treatment outcome in unipolar depression and the paucity of data on the role of anxiety in bipolar disorder, the authors sought to determine the effect of anxiety on the acute treatment response of patients with bipolar I disorder. METHOD: The authors examined the correlates of response to the acute treatment of 124 consecutively treated patients with bipolar I disorder. Measures of anxiety included history of panic attacks and a composite variable reflecting current or past anxiety symptoms. RESULTS: History of panic attacks proved to be a significant correlate of nonremission. Anxiety, as assessed with the composite variable, was associated with longer time to remission, as was the treatment of depressive versus manic symptoms and mixed versus manic symptoms. Patients with anxiety as assessed with the composite variable and patients with a history of panic attacks reported more severe medication side effects. They also required a greater number of medications, either sequentially or in combination, in order to achieve remission. CONCLUSIONS: The findings suggest that anxiety is a clinically meaningful correlate of poor outcome in the acute treatment of bipolar I disorder.     

Differential item functioning of DSM-IV depressive symptoms in individuals with a history of mania versus those without: an item response theory analysis

Objectives:  Although major depression is characteristic of both bipolar disorder and major depressive disorder, there is disagreement as to whether there are distinct features of depression that differentiate these two conditions. The primary aim of this study was to use methods based in item response theory to evaluate differences in DSM-IV depression symptom endorsement in an epidemiological sample of individuals with a history of mania (i.e., bipolar depression) versus those without (i.e., unipolar depression).
Methods:  Clinical interview data were drawn from a subsample (n = 13,058) of individuals with bipolar or unipolar depression who had participated in the National Epidemiologic Survey on Alcohol and Related Conditions. Using these data, a two-parameter item response model was used to estimate differential item functioning of DSM-IV depressive symptoms between these two groups.
Results:  Differences in severity parameter estimates revealed that suicidal ideation and psychomotor disturbance were more likely to be endorsed across most levels of depression severity in bipolar versus unipolar depression. Differences in discrimination parameter estimates revealed that fatigue was significantly less discriminating in bipolar versus unipolar depression.
Conclusions:  Equating for level of depression symptom severity, study results revealed that suicidal ideation and psychomotor disturbance are endorsed more frequently in bipolar versus unipolar depression. Study data also suggested that fatigue may be endorsed more frequently in unipolar relative to bipolar samples at moderate (versus low or high) levels of depression symptom severity.     

Ultra-brief pulse ECT in bipolar and unipolar depressive disorder: differences in speed of response

Objectives:  There is little evidence for differences in response and speed of response to electroconvulsive therapy (ECT) between patients with bipolar and patients with unipolar depressive disorder. In the only prospective study to date, Daly et al. (Bipolar Disord 2001; 3: 95–104) found patients with bipolar depression to show more rapid clinical improvement and require fewer treatments than unipolar patients. In this study, response and speed of response of patients with unipolar and bipolar depression treated with ultra-brief pulse ECT were compared.
Methods:  All patients (n = 64) participated in a randomized trial comparing ultra-brief pulse bifrontal ECT at 1.5 times seizure threshold and unilateral ECT at 6 times seizure threshold. Thirteen patients (20.3%) had DSM-IV-defined bipolar depression. The Hamilton Rating Scale for Depression and Clinical Global Impression scale were administered at baseline and repeated weekly during and after the course of treatment by a blinded rater. At the same time point, the Beck Depression Inventory and the Patient Global Impression scale were administered. Speed of response was analyzed using survival analyses.
Results:  Patients with bipolar and unipolar depression did not differ in rates of response or remission following the ECT course, nor in response to unilateral or bifrontal ECT. Patients with bipolar depression, however, showed a more rapid response than patients with unipolar depression.
Conclusions:  Patients with bipolar depression tend to show more rapid clinical improvement with ECT than patients with unipolar depression.     

Retrospective age at onset of bipolar disorder and outcome during two-year follow-up: results from the STEP-BD study

Objective:  Symptoms of bipolar disorder are increasingly recognized among children and adolescents, but little is known about the course of bipolar disorder among adults who experience childhood onset of symptoms.
Methods:  We examined prospective outcomes during up to two years of naturalistic treatment among 3,658 adult bipolar I and II outpatients participating in a multicenter clinical effectiveness study, the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD). Age at illness onset was identified retrospectively by clinician assessment at study entry.
Results:  Compared to patients with onset of mood symptoms after age 18 years (n = 1,187), those with onset before age 13 years (n = 1,068) experienced earlier recurrence of mood episodes after initial remission, fewer days of euthymia, and greater impairment in functioning and quality of life over the two-year follow-up. Outcomes for those with onset between age 13 and 18 years (n = 1,403) were generally intermediate between these two groups.
Conclusion:  Consistent with previous reports in smaller cohorts, adults with retrospectively obtained early-onset bipolar disorder appear to be at greater risk for recurrence, chronicity of mood symptoms, and functional impairment during prospective observation.     

Childhood mania,attention deficit hyperactivity disorder and conduct disorder: a critical review of diagnostic dilemmas

Objectives:  Significant debate exists on whether early onset bipolar disorder is mistakenly attributed to attention deficit hyperactivity disorder (ADHD) or conduct disorder (CD), or whether ADHD and CD are frequently misdiagnosed as mania. We review the literature on the extent to which these disorders can be reliably differentiated, and describe the diagnostic confusion that may be the result of features common to both classes of disorders.
Methods:  The review focuses on research studies that have examined whether overlapping symptoms of bipolar disorder, ADHD, and CD contribute to misdiagnosis of the two classes of disorders, the prevalence of early onset bipolar disorder with comorbid ADHD or CD, and theories regarding the origins of this comorbidity.
Results:  Reliable and accurate diagnoses can be made despite the symptom overlap of bipolar disorder with ADHD and CD. Children with bipolar disorder and ADHD may have a distinct familial subtype of bipolar disorder. Some findings suggest that manic symptoms may represent `noise' that indicates the general severity of psychopathology in a child or adolescent.
Conclusions:  Further prospective studies may confirm whether early onset bipolarity can be successfully differentiated from ADHD or CD, whether all three types of disorders can be recognized in comorbid cases, or whether comorbid cases represent a distinct subtype of bipolar disorder.     

Comorbidity of adult attention-deficit hyperactivity disorder and bipolar disorder: prevalence and clinical correlates

The aim of this study was to determine the frequency of adult attention deficit hyperactivity disorder (ADHD) comorbidity with lifetime bipolar disorder, and the influence of this comorbidity on various demographic and clinical variables in patients. Patients (n = 159) with a previous diagnosis of bipolar disorder (79 female, 80 male) were included in this study. All patients were interviewed for the presence of current adult and childhood ADHD diagnosis and other axis I psychiatric disorder comorbidities using the structured clinical interview for DSM-IV (SCID) and the Schedule for Affective Disorders and Schizophrenia for School Age Children—Present and Lifetime Version (K-SADS-PL). The subjects also completed a Wender Utah rating scale (WURS-25) and a Current Symptoms Scale for ADHD symptoms. In particular, patients’ clinical characteristics, the age of onset of bipolar disorder, and the number of episodes were noted. Twenty-six of the 159 bipolar patients (16.3%) were diagnosed with adult ADHD, while another subgroup of patients (n = 17, 10.7%) received a diagnosis of childhood ADHD but did not fulfill criteria for adult ADHD. Both of these two subgroups (patients with adult ADHD, and patients with only childhood ADHD) had an earlier age of onset of the disease and a higher number of previous total affective or depressive episodes than those without any lifetime ADHD comorbidity. However only bipolar patients with adult ADHD comorbidity had higher lifetime comorbidity rates for axis I psychiatric disorders, such as panic disorder and alcohol abuse/dependence, compared to patients without lifetime ADHD. Bipolar patients with comorbid adult ADHD did not differ from bipolar patients with comorbid childhood ADHD in terms of any demographic or clinical variables except for adult ADHD scale scores. In conclusion, ADHD is a common comorbidity in bipolar patients, and it adversely affects the course of the disease and disrupts the social adjustment of the patients. Regular monitoring of ADHD will help to prevent problems and complications that could arise in the course of the disease, particularly in patients with early onset bipolar disorder.     

Implicit motives and cognitive variables: Specific links to vulnerability for unipolar or bipolar disorder

Cognitive variables contribute to the etiology of affective disorders. With the differentiation between explicit and implicit measures some studies have indicated underlying depressogenic schemata even in bipolar disorders. We tested for differences in implicit motives and cognitive variables between patients with remitted unipolar and bipolar disorder compared to controls and in a high-risk sample. Additionally we investigated whether affective symptoms relate to those variables. We cross-sectionally examined N=164 participants (53 with bipolar disorder, 58 with major depression, and 53 without affective disorders) and a high-risk sample (N=49) of adolescent children of either parents with unipolar or bipolar disorder or of healthy parents. The Multi-Motive-Grid was used to measure the implicit motives achievement, affiliation, and power, in addition to the cognitive measures of self-esteem, dysfunctional attitudes, and perfectionism. Unipolar and bipolar groups did not differ from healthy controls in implicit motives but showed higher scores in the cognitive factors. Adolescents at high risk for unipolar disorder showed lower scores in the power and achievement motives compared to adolescents at low risk. Subsyndromal depressive symptoms were related to the cognitive variables in both samples. Our results underline the importance of cognitive-behavioral treatment for both unipolar and bipolar disorder.     

Polarity at illness onset in bipolar I disorder and clinical course of illness

Objectives:  Studies have suggested that episode polarity at illness onset in bipolar disorder may be predictive of some aspects of lifetime clinical characteristics. We here examine this possibility in a large, well-characterized sample of patients with bipolar I disorder.
Methods:  We assessed polarity at onset in patients with bipolar I disorder (N = 553) recruited as part of our ongoing studies of affective disorders. Lifetime clinical characteristics of illness were compared in patients who had a depressive episode at first illness onset (n = 343) and patients who had a manic episode at first illness onset (n = 210).
Results:  Several lifetime clinical features differed between patients according to the polarity of their onset episode of illness. A logistic regression analysis showed that the lifetime clinical features significantly associated with a depressive episode at illness onset in our sample were: an earlier age at illness onset; a predominantly depressive polarity during the lifetime; more frequent and more severe depressive episodes; and less prominent lifetime psychotic features.
Conclusions:  Knowledge of pole of onset may help the clinician in providing prognostic information and management advice to an individual with bipolar disorder.     

Types of depression more frequent in bipolar than in unipolar affective illness: results of the Polish DEP-BI study

BACKGROUND: The aim of the study was to assess the relative frequency of various kinds of depression in patients with bipolar and unipolar affective illness. The study was performed in the framework of the DEP-BI project aimed at assessing the prevalence of bipolar disorders among depressive outpatients treated by psychiatrists in Poland. METHODS: Eight-hundred and eighty patients (237 male, 643 female) participated in the study. The patients were classified into the following diagnostic categories: bipolar affective illness type I, type II, bipolar spectrum disorder and unipolar affective illness. The various kinds of depression in each group were assessed by means of a semistructured questionnaire added to the diagnostic interview. RESULTS: In the group of bipolar patients, a significantly higher frequency of psychotic depression in male compared to female patients was observed. Male bipolar patients compared with unipolar depressed ones had significantly more episodes of psychotic depression (odds ratio, OR, 4.29) and atypical depression (hypersomnia and hyperphagia; OR 2.82), and those with bipolar spectrum had more episodes of treatment-resistant depression (OR 2.56). Female bipolar patients compared with unipolar depressed ones had significantly more frequently an early onset of depression (before 25 years; OR 2.95) and postpartum depression (OR 2.48). On the other hand, the percentage of agitation, irritability, distractibility, thought racing and panic attacks during depression was not different in patients with bipolar and unipolar affective illness either in males or females. CONCLUSIONS: Some kinds of depression occur with a higher frequency in patients with bipolar compared to unipolar affective illness. The occurrence of a given type of depression may constitute an aid for the diagnosis of bipolar illness. The results of this study did not confirm the concept of bipolar mixed depression based on the presence of anxiety symptoms occurring during the depressive episode. The limitation of our study may be the lack of formal criteria or a structured interview to assess the symptoms occurring during depressive episodes.     

Smaller amygdala is associated with anxiety in patients with panic disorder

Aims:  Anxiety a core feature of panic disorder, is linked to function of the amygdala. Volume alterations in the brain of patients with panic disorder have previously been reported, but there has been no report of amygdala volume association with anxiety.
Methods:  Volumes of hippocampus and amygdala were manually measured using magnetic resonance imaging obtained from 27 patients with panic disorder and 30 healthy comparison subjects. In addition the amygdala was focused on, applying small volume correction to optimized voxel-based morphometry (VBM). State–Trait Anxiety Inventory and the NEO Personality Inventory Revised were also used to evaluate anxiety.
Results:  Amygdala volumes in both hemispheres were significantly smaller in patients with panic disorder compared with control subjects (left: t = −2.248, d.f. = 55, P  = 0.029; right: t = −2.892, d.f. = 55, P  = 0.005). VBM showed that structural alteration in the panic disorder group occurred on the corticomedial nuclear group within the right amygdala (coordinates [x,y,z (mm)]: [26,−6,−16], Z score = 3.92, family-wise error-corrected P  = 0.002). The state anxiety was negatively correlated with the left amygdala volume in patients with panic disorder (r = −0.545, P  = 0.016).
Conclusions:  These findings suggested that the smaller volume of the amygdala may be associated with anxiety in panic disorder. Of note, the smaller subregion in the amygdala estimated on VBM could correspond to the corticomedial nuclear group including the central nucleus, which may play a crucial role in panic attack.