Is major depression a cognitive disorder?

This is a review of cognitive abilities in major depression, which is associated with attention problems, memory deficit and wide impairment in executive functions. Depressed patients show two major cognitive biases: excessive processing of negatively valenced emotional stimuli; and increased self-focus. Both of these biases help to facilitate the integration of negative self-related information in depressed patients and to maintain their negative mood. Brain imaging studies suggest that this cognitive impairment is characterized by abnormal cooperation between the cognitive and limbic networks involved in cognitive control and self-referential processing. In general, depression is a disorder of multiple networks with emotional, cognitive and emotional symptoms. Among these symptoms, cognition is a major determinant of functional and social outcomes.     

Is major depressive disorder specifically associated with mesial temporal sclerosis?

Purpose: Whether a specific lesion such as mesial temporal sclerosis (MTS) increases the risk for a mood disorder in epilepsy remains subject to debate. Despite evidence of limbic system involvement in the genesis of emotional symptoms, recent studies fail to support an association between depression and MTS. We aimed to clarify this controversial issue by overcoming prior methodologic limitations, hypothesizing that rates of major depressive disorder (MDD) would be higher in patients with MTS. Methods: Three hundred eight patients with focal epilepsy (International League Against Epilepsy [ILAE] criteria), were classified into three groups on the basis of neuroimaging findings: MTS, a lesion different from MTS, or absence of lesion. Patients were assessed using the Structured Interview for DSM‐IV axis I psychiatric disorders (SCID‐I), by a psychiatrist blinded to epilepsy subtype. The Spanish version of the Hospital Anxiety and Depression Scale (HADS) was also administered. A complete logistic regression analysis was performed to investigate the association between MTS and MDD. Key Findings: MTS increased the likelihood of a lifetime MDD by nearly 2.5. No other current or “postseizure onset” lifetime Axis I DSM‐IV psychiatric disorder was associated with MTS. Female gender, primary education, comorbid anxiety disorders, and antidepressant treatment were also associated with an increased risk of MDD. Marriage was found to be a protective factor for MDD. Significance: Our results support a specific association between MTS and lifetime “postseizure onset,” MDD. The lack of association with current depression is in line with the hypothesis that the link between MTS and depression is more of a chronic than a state‐dependent condition.     

Is a patient‐administered depression rating scale valid for detecting cognitive deficits in patients with major depressive disorder?

Aims: Although cognitive deficits are a common and potentially debilitating feature of major depressive disorder (MDD), such subjective declines in cognitive function are seldom validated by objective methods as a clinical routine. The aim of this study was to validate the Taiwanese Depression Questionnaire (TDQ) for detecting cognitive deficits in a sample of drug‐free patients with MDD. Methods: The subjects consisted of 40 well‐characterized medication‐free patients with MDD and 40 healthy controls. Clinical and neuropsychological assessments, including the Wisconsin Card Sorting Test, the Wechsler Memory Scale–Revised, the Continuous Performance Test, and the Finger‐Tapping Test, were administered at the time of recruitment. Results: Factor analyses of the TDQ yielded three factors. Memory, attention and psychomotor performance were significantly poorer in patients with MDD. The performances of verbal and delayed memory of the Wechsler Memory Scale–Revised were correlated with the cognitive domains of the TDQ. Generalization of our results must be undertaken with caution considering the relatively small sample size, which could lead to increased β‐error. Conclusion: Cognitive subdomains might be considered important for including in patient‐administered questionnaires used to measure symptoms of MDD when developing a new scale.     

Is the association of alcohol use disorders with major depressive disorder a consequence of undiagnosed bipolar-II disorder?

BACKGROUND: There is emerging evidence that there is a spectrum of expression of bipolar disorder. This paper uses the well-established patterns of comorbidity of mood and alcohol use disorder to test the hypothesis that application of an expanded concept of bipolar-II (BP-II) disorder might largely explain the association of alcohol use disorders (AUD) with major depressive disorder (MDD). METHOD: Data from the Zurich study, a community cohort assessed over 6 waves from ages 20/21 to 40/41, were used to investigate the comorbidity between mood disorders and AUD. Systematic diagnostic criteria were used for alcohol abuse, alcohol dependence, MDD, and BP-II. In addition to DSM criteria, two increasingly broad definitions of BP-II were employed. RESULTS: There was substantially greater comorbidity for the BP-II compared to major depression and for alcohol dependence compared to alcohol abuse. The broadest concept of BP-II explained two thirds of all cases of comorbidity of AUD with major depressive episodes (MDE). In fact, the broader the definition of BP-II applied, the smaller was the association of AUD with MDD, up to non-significance. In the majority of cases, the onset of bipolar manifestations preceded that of drinking problems by at least 5 years. CONCLUSIONS: The findings that the comorbidity of mood disorders with AUD was primarily attributable to BP-II rather than MDD and that bipolar symptoms usually preceded alcohol problems may encourage new approaches to prevention and treatment of AUD.     

Is major depressive disorder in adolescence a distinct diagnostic entity?

The concept of major depressive disorder in childhood and adolescence is reviewed and it is suggested that contemporary enthusiasm for this diagnosis may have outrun the evidence that it is a distinct categorical entity. To test the hypothesis that major depression is not a qualitatively distinct disorder in adolescence, but rather a continuously distributed, noncategorical syndrome, the behavioral rating scales (CBCL-P) of 216 hospitalized adolescent patients were analyzed first by principal components analysis and then by cluster analysis. Three behavioral syndromes were isolated by principal components analysis. Of three groups of patients identified by a subsequent cluster analysis, one was consistent with the concept of a categorically distinct "nuclear" depression. However, a noncategorical continuously distributed depressive syndrome appears to affect a larger number of patients in this age group, and the "nuclear" disorder may be less prevalent than is currently assumed. One explanation of these findings would combine a categorical model of nuclear depression with a dimensional model of dysthymia.     

Double depression in adult psychiatric outpatients in Brazil: distinct from major depression?

This study examines whether distinct symptom profiles, patterns of comorbidity, and suicidal symptoms uniquely characterize individuals diagnosed with double depression (DD) by comparing Brazilians with DD to those with major depressive disorder (MDD). One hundred forty two psychiatric outpatients (ages 20-77 mean=48.8, S.D.=13.2; DD, n=23; MDD, n=119) participated in structured diagnostic interviews and completed self-report measures of depressive symptoms, suicidality, and family history of mental disorders. Patients with DD exhibited a more severe symptom profile than those with MDD, as evidenced by a higher number of depressive symptoms and more intense suicidal ideation. They also appeared to be qualitatively different from individuals with MDD, as evidenced by distinct comorbidity patterns, quality of life reports, and anhedonic features. These results may be important in understanding the phenomenology of DD in psychiatric outpatients by informing diagnostics, psychotherapy, and psychotherapeutic treatment of DD.     

Generalized anxiety disorder in patients with major depression: is DSM-IV's hierarchy correct?

OBJECTIVE: DSM-III imposed a hierarchical relationship in the diagnosis of anxiety disorders in depressed patients, stipulating that anxiety disorders could not be diagnosed if their occurrence was limited to the course of a mood disorder. In the subsequent versions of the DSM this hierarchy was eliminated for all anxiety disorders except generalized anxiety disorder. The authors examined the validity of this remaining hierarchical relationship between mood and anxiety disorders. METHOD: Psychiatric outpatients with major depressive disorder (N=332) were evaluated with a semistructured diagnostic interview and completed paper-and-pencil questionnaires on presentation for treatment. To study the validity of the DSM-IV hierarchical relationship between generalized anxiety disorder and mood disorders, the authors made a diagnosis of modified generalized anxiety disorder for patients with major depressive disorder who met all the criteria for generalized anxiety disorder except for the exclusion criterion. The analyses compared the characteristics of three nonoverlapping groups of patients with DSM-IV major depressive disorder: 1) those with coexisting DSM-IV generalized anxiety disorder, 2) those with coexisting modified generalized anxiety disorder, and 3) those with neither DSM-IV nor modified generalized anxiety disorder. RESULTS: Compared to the depressed patients without generalized anxiety disorder, the depressed patients with DSM-IV and modified generalized anxiety disorder had higher levels of suicidal ideation; poorer social functioning; a greater frequency of other anxiety disorders, eating disorders, and somatoform disorders; higher scores on most subscales of a multidimensional self-report measure of DSM-IV axis I disorders; a greater level of pathological worry; and a higher morbid risk for generalized anxiety disorder in first-degree family members. The two generalized anxiety disorder groups did not differ from each other. CONCLUSIONS: The findings question the validity of the DSM-IV hierarchical relationship between major depressive disorder and generalized anxiety disorder and suggest that the exclusion criterion should be eliminated.     

Is stroke a HIV-related neurologic manifestation?

Neurologic illnesses occur commonly in association with HIV infection, are frequently debilitating and often life-threatening. The commonly recognized HIV-related neurologic illnesses include encephalopathy (dementia), myelopathy, neuropathy and myopathy. Stroke as a HIV-related manifestation is an increasingly recognized and evolving issue. This article reviews the literature on the association of stroke and HIV, stroke risk and stroke mechanisms in HIV-infected patients, and the role of antiretroviral drugs in HIV-related stroke.     

Does a coexisting anxiety disorder predict persistence of depressive illness in primary care patients with major depression?

We assessed whether a coexisting anxiety disorder predicts risk for persistent depression in primary care patients with major depression at baseline. Patients with major depression were identified in a 12-month prospective cohort study at a University-based family practice clinic. Presence of an anxiety disorder and other potential prognostic factors were measured at baseline. Persistent depressive illness (major depression, minor depression, or dysthymia) was determined at 12 months. Of 85 patients with major depression at baseline, 43 had coexisting anxiety disorder (38 with social phobia). The risk for persistent depression at 12 months was 44% greater [Risk Ratio (RR) = 1.44, 95% confidence interval (CI) 1.02-2.04] in those with coexisting anxiety. This risk persisted in stratified analysis controlling for other prognostic factors. Patients with coexisting anxiety had greater mean depressive severity [repeated measures analysis of variance (ANOVA), p < 0.04] and total disability days (54.9 vs 19.8, p < 0.02) over the 12-month study. Patients with social phobia had similar increased risk for persistent depression (RR = 1.40, 95% CI 0.98-2.00). A coexisting anxiety disorder indicates risk for persistent depression in primary care patients with major depression. Social phobia may be important to recognize in these patients. Identifying anxiety disorders can help primary care clinicians target patients needing more aggressive treatment for depression.     

Is "somatisation" a defense against the acknowledgment of psychiatric disorder?

OBJECTIVE: To determine whether experiencing physical symptoms is associated with a denial of psychological distress in individuals with probable psychiatric disorder. METHODS: A nested case-control study was performed using data from a national birth cohort study. All subjects who scored above threshold on a case-finding questionnaire of psychiatric disorder were identified. Those who in a separate question endorsed the presence of psychiatric disorder ("acknowledgers") were compared with those who did not. RESULTS: Acknowledgers were more likely to be female, better educated and have more severe current and past psychiatric disorder. They were also more likely to report multiple physical symptoms, even when potential confounders and severity of psychiatric disorder were controlled. CONCLUSION: There is no evidence that experiencing multiple physical symptoms helps the individual deny the presence of psychiatric disorder.     

A continuity between bipolar II depression and major depressive disorder?

BACKGROUND: A recent series of studies has questioned the current categorical split of mood disorders into bipolar and depressive disorders. Mixed states, especially mixed depression (i.e., depression plus co-occurring, noneuphoric, hypomanic symptoms) might support a continuity between bipolar II (BP-II) depression and major depressive disorder (MDD). The aim of the study was to assess the distribution of intradepressive hypomanic symptoms rating between BP-II and MDD depressions. A bi-modal distribution would support a categorical distinction, and no bi-modality would support continuity. METHODS: Consecutive 389 BP-II and 261 MDD major depressive episode (MDE) outpatients were interviewed (off psychoactive drugs) with the Structured Clinical Interview for DSM-IV, the Hypomania Interview Guide (HIG, to assess intradepressive hypomanic symptoms), and the Family History Screen, by a mood specialist psychiatrist in a private practice. Mixed depression was defined as MDE plus 3 or more intradepressive, noneuphoric hypomanic symptoms, a definition validated by Akiskal and Benazzi. The distribution of intradepressive hypomanic symptoms rating was studied by Kernel density estimate and by histogram. RESULTS: BP-II depression, versus MDD depression, had significantly lower age at onset, was significantly more likely to be atypical and mixed, had more depression recurrences, and a higher bipolar family history loading. BP-II depression, versus MDD depression, had significantly more irritability, racing/crowded thoughts, distractibility, psychomotor agitation, talkativeness, increased goal-directed activity, and excessive risky activities. HIG scores were significantly higher in BP-II. The distribution of intradepressive hypomanic symptoms rating showed no bi-modality in the entire depression sample. CONCLUSIONS: Interpretation of study findings relies on the method used to define a categorical disorder. By using classic diagnostic validators (such as family history and age at onset), BP-II and MDD depressions would seem to be distinct disorders. Instead, by using the 'bi-modality' approach, a continuity would seem to be supported. Which of these methods for classification is the best has yet to be shown.     

When does depression become a mental disorder?

How can we differentiate a depressive disorder from 'normal' sadness? This editorial summarises three approaches: the first emphasises the context in which depressive symptoms occur; the second postulates a qualitative difference between the two conditions; and the third argues that the distinction should be based on pragmatic grounds.