The three-year naturalistic course of major depressive disorder, dysthymic disorder and double depression

Mental health outcome of long-term and episodic adolescent depression: 15-year follow-up of a community sample

BACKGROUND

Recent studies have highlighted the unfavourable natural course of chronic/long-term depression. We investigated the adult mental health outcome of adolescent depression, with specific focus on long-term and episodic adolescent major depression (MD).

METHODS

A community sample of depressed adolescents and non-depressed peers was followed-up with a structured diagnostic interview after 15 years. The participants (n=382) were divided into five groups depending on their status in adolescence: no depression (n=155); long-term MD (n=91); episodic MD (n=63); dysthymia (n=33); and subthreshold symptoms (n=40). Outcomes (age 19-31) included mood disorders, other mental disorders, suicidality, and treatment for mental disorders.

RESULTS

The long-term group overall had a poorer outcome than the non-depressed group, with the episodic group in an intermediate position. The outcome of the dysthymic group was similar to that of the long-term group, while the subsyndromal group did not differ markedly from the non-depressed group. The long-term group was more likely than the episodic group to report adult anxiety disorders, multiple mental disorders, suicide attempts, and treatment; they also seemed to develop more persistent adult depressions, with a higher number of recurrent episodes and longer duration of antidepressant treatment. Even after adjustment for adolescent factors of clinical and etiological importance, the long-term group had a markedly less favourable outcome than the episodic group.

LIMITATION

The participation rate at follow-up was 64.6%.

CONCLUSION

Longstanding depression in adolescence is a powerful predictor of continued mental health problems in adulthood. It is now important to evaluate if early interventions can alter this severe course.

The 7-year course of depression and anxiety in the general population

OBJECTIVE

Insight into the long-term course of depression and anxiety.

METHOD

Data were derived from Netherlands Mental Health Survey and Incidence Study/Netherlands Study of Depression and Anxiety, epidemiologic surveys in the adult population in the Netherlands. Three hundred and three respondents with depressive and/or anxiety Composite International Diagnostic Interview (CIDI) disorder were interviewed, examining the 7-year course of depression (n = 141), anxiety (n = 102) and the comorbid state (n = 60) and possible prognostic factors. Outcomes were CIDI diagnostic status after 7 years and percentage of time during 7 years with depressive and/or anxiety symptoms, retrospectively assessed by the Life Chart Interview (LCI).

RESULTS

After 7 years, 60.7% of the subjects were free from a 12-month CIDI depression or anxiety diagnosis. The odds were higher for subjects with anxiety and comorbidity compared to subjects with depression. Low physical functioning and high neuroticism predicted the presence of a diagnosis after 7 years. During 7-year follow-up, 37.3% of the subjects were free from depressive and anxiety symptoms according to the LCI, 51.8% had symptoms <50% of the time, and 10.9%≥50% of the time. (Comorbid) anxiety resulted in a poorer course. High neuroticism and childhood adversity predicted more follow-up time with symptoms.

CONCLUSION

Course trajectories were more favorable than expected, although comorbidity resulted in poorer course. Neuroticism, physical functioning, and childhood adversity predicted an unfavorable course.

Dysthymia in a cross-cultural perspective

PURPOSE OF REVIEW

Dysthymia is a relatively less-studied condition within the spectrum of depressive disorders. New and important information about its status has emerged in recent scientific literature. This review highlights some of the findings of that literature.

RECENT FINDINGS

Even though studies addressing the cross-cultural validity of dysthymia are being awaited, results of studies using comparable ascertainment procedures suggest that the lifetime and 12-month estimates of the condition may be higher in high-income than in low and middle-income countries. However, the disorder is associated with elevated risks of suicidal outcomes and comparable levels of disability whereever it occurs. Dysthymia commonly carries a worse prognosis than major depressive disorder and comparable or worse clinical outcome than other forms of chronic depression. Whereas there is some evidence that psychotherapy may be less effective than pharmacotherapy in the treatment of dysthymia, the best treatment approach is one that combines both forms of treatment.

SUMMARY

Dysthymia is a condition of considerable public health importance. Our current understanding suggests that it should receive more clinical and research attention. Specifically, the development of better treatment approaches, especially those that can be implemented in diverse populations, deserves research attention.

Impairment in psychosocial functioning associated with dysthymic disorder in the NESARC study

BACKGROUND

Chronic depression is associated with impaired functioning. The National Epidemiologic Survey of Alcoholism and Related Conditions (NESARC) is a representative sample (N=43,093) of the United States non-institutionalized population aged 18years and older. We hypothesized that individuals with chronic low-grade depression, dysthymic disorder, would have more impaired functioning than individuals with acute major depression or the general population.

METHOD

Diagnoses were generated by the NIAAA Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV Version (AUDADIS-IV). The dysthymic disorder (DD) sample (N=328) consisted of DD diagnosis without current MDD. The dysthymic group was not chosen on the basis of alcohol use or abuse. Individuals with MDD with duration ≦24months, without lifetime DD constituted the acute depression (AD) sample (N=712). All other respondents were classified as general population (GP) (N=42,052). Past year functioning was assessed by Supplemental Social Security Income (SSI), employment, and Medicaid statuses. Past month functioning was assessed by Short-form 12-Item Health Survey (SF-12), with scores for social functioning, role emotional functioning, and mental health, using odds ratios.

RESULTS

Over the past year, compared to AD, persons with DD were less likely to work full-time (36.2% vs. 44%; OR=0.70, CI=.54,.92) and more often received SSI (13.9% vs. 4.5%; OR=3.4, CI=2.0,5.9) and Medicaid (20.2% vs. 13%; OR=1.7 , CI=1.1,2.6). Dysthymics reported accomplishing less over the past month due to emotional problems, and that emotional or physical problems interfered with social activities. Relative to GP, respondents with DD were more likely to receive SSI (13.9% vs. 2.9%; OR=4.6, CI 3.4,6.2) and Medicaid (20.2% vs. 5.9%; OR=2.9, CI 2.0,4.1). Compared to GP, dysthymics reported accomplishing less due to emotional problems, and that emotional or physical problems interfered with social activities and work functioning.

CONCLUSIONS

DD-associated psychosocial impairment in the community setting comprises a significant public health burden.

Chronic Depression

Traditionally, non-bipolar depression has been viewed as an episodic, remitting condition. However, with the recognition that depressions can persist for many years, the current diagnostic classification system includes various forms of chronic depression. The distinction between chronic and nonchronic depressions is useful for reducing the heterogeneity of the disorder. Individuals with chronic depression differ from those with nonchronic depression on a variety of clinically and etiologically significant variables, including comorbidity, impairment, suicidality, history of childhood maltreatment, familial psychopathology, and long-term course. In contrast, there is little support for current distinctions between different forms of chronic depression. This suggests that it may be simpler to collapse the existing forms of chronic depression in the current classification system into a single category. However, there is growing evidence that other characteristics, such as age of onset and a childhood history of early adversity, may provide meaningful approaches to subtyping chronic depression.

Noninvasive techniques for probing neurocircuitry and treating illness: vagus nerve stimulation (VNS), transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS)

Although the preceding chapters discuss much of the new knowledge of neurocircuitry of neuropsychiatric diseases, and an invasive approach to treatment, this chapter describes and reviews the noninvasive methods of testing circuit-based theories and treating neuropsychiatric diseases that do not involve implanting electrodes into the brain or on its surface. These techniques are transcranial magnetic stimulation, vagus nerve stimulation, and transcranial direct current stimulation. Two of these approaches have FDA approval as therapies.

Cognitive reactivity mediates the relationship between neuroticism and depression

Although neuroticism has long been established as an important risk factor for depression, the mechanisms through which this temperamental predisposition translates into the occurrence of symptoms are still relatively unclear. This study investigated cognitive reactivity, i.e. the ease with which particular patterns of negative thinking are reactivated in response to mild low mood, as a potential mediator. Individuals with (N = 98) and without a previous history of depression (N = 83) who had provided neuroticism scores six years previously were assessed for cognitive reactivity and current symptoms of depression using self-report questionnaires. Tendencies to respond to mild low mood with ruminative thinking mediated the relation between neuroticism and current symptoms of depression in both groups. Reactivation of hopelessness and suicidal thinking occurred as an additional mediator only in those with a history of previous depression. The results suggest that neuroticism predisposes individuals to depression by generally increasing the likelihood of ruminative responses to low mood. In those with a history of depression in the past, neuroticism additionally increases risk of recurrence by facilitating reactivation of previously associated patterns such as suicidal thinking and hopelessness. These findings suggest potential targets for interventions to help preventing the occurrence, or recurrence of depression in those who due to their temperamental predisposition are at an increased risk.

Emotional disorders: cluster 4 of the proposed meta-structure for DSM-V and ICD-11

BACKGROUND

The extant major psychiatric classifications DSM-IV, and ICD-10, are atheoretical and largely descriptive. Although this achieves good reliability, the validity of a medical diagnosis would be greatly enhanced by an understanding of risk factors and clinical manifestations. In an effort to group mental disorders on the basis of aetiology, five clusters have been proposed. This paper considers the validity of the fourth cluster, emotional disorders, within that proposal.

METHOD

We reviewed the literature in relation to 11 validating criteria proposed by a Study Group of the DSM-V Task Force, as applied to the cluster of emotional disorders.

RESULTS

An emotional cluster of disorders identified using the 11 validators is feasible. Negative affectivity is the defining feature of the emotional cluster. Although there are differences between disorders in the remaining validating criteria, there are similarities that support the feasibility of an emotional cluster. Strong intra-cluster co-morbidity may reflect the action of common risk factors and also shared higher-order symptom dimensions in these emotional disorders.

CONCLUSION

Emotional disorders meet many of the salient criteria proposed by the Study Group of the DSM-V Task Force to suggest a classification cluster.

Meta-analysis of the placebo response in antidepressant trials

Improvements in placebo groups of antidepressant trials account for a major part of the expected drug effects. We aimed to determine overall effect sizes of placebo and drug effects in antidepressant trials, and to analyze whether the placebo effect in antidepressant trials also occurs for patient self-perception, general psychopathology, and quality of life.

METHODS

Search terms covered different variants of pharmacotherapy for patients with depressive disorders from January 1980 to December 2005 in the databases Medline/Pubmed, PsychInfo and CENTRAL, a.o. We included RCTs with a placebo group and an antidepressant group in people with depression.

RESULTS

We computed within group effect sizes for several outcome variables and integrated them using random-effect models. A total of 96 studies were included. Mean effect size in the placebo group for primary outcome variables was d=1.69 (95% CI=1.54-1.84) compared to 2.50 in the drug group (95% CI=2.30-2.69). There was a major difference between placebo effect sizes assessed with observer ratings (d=1.85, 95% CI=1.69-2.01) versus patient self-perception (d=0.67; 95% CI=0.49-0.85). The effect sizes in placebo groups in 2005 were more than twice as great as those in 1980, but only for observer ratings, not for patient self-ratings. The result was partly due to increased homogeneity of samples of recently published trials.

CONCLUSIONS

The placebo effect accounted for 68% of the effect in the drug groups. Whereas clinical trials need to control the placebo effect, clinical practice should attempt to use its full power.