Perceived stress and cognitive vulnerability mediate the effects of personality disorder comorbidity on treatment outcome in major depressive disorder: a path analysis study

Prognostic Value of Pathological Personality Traits for Treatment Outcome in Anxiety and Depressive Disorders: The Leiden Routine Outcome Monitoring Study

ABSTRACT

Previous studies have failed to take baseline severity into account when assessing the effects of pathological personality traits (PPT) on treatment outcome. This study assessed the prognostic value of PPT (Dimensional Assessment of Personality Pathology-Short Form) on treatment outcome (Brief Symptom Inventory [BSI-posttreatment]) among patients with depressive and/or anxiety disorders ( N = 5689). Baseline symptom level (BSI-pretreatment) was taken into account as a mediator or moderator variable. Results showed significant effects of PPT on outcome, of which Emotional Dysregulation demonstrated the largest association ( β = 0.43, p < 0.001). When including baseline BSI score as a mediator variable, a direct effect ( β = 0.11, p < 0.001) remained approximately one-third of the total effect. The effects of Emotional Dysregulation (interaction effect β = 0.061, p < 0.001) and Inhibition (interaction effect β = 0.062, p < 0.001), but not Compulsivity or Dissocial Behavior, were moderated by the baseline symptom level. PPT predicts higher symptom levels, both before and after treatment, but yields relatively small direct effects on symptom decline when the effect of pretreatment severity is taken into account.

Resting frontal brain asymmetry is linked to future depressive symptoms in women

This longitudinal pilot study examined whether baseline resting frontal electroencephalographic (EEG) asymmetry correlates with depressive symptoms during the most impaired two-week period in the following year. Current-source-density (CSD) transformed resting frontal EEG asymmetry, severity of depression symptoms (Beck Depression Inventory - II), and stress (indexed by negative life events; NLE) were recorded in never-depressed young adults with no current DSM-IV diagnosis (38 women, 16 men) at baseline. One year later, depression symptoms and NLEs experienced during the interim were assessed. Individuals who reported greater interim NLEs also endorsed interim higher depression symptoms, a pattern that replicated when first accounting for baseline stress and depression. For women, higher depression reported at follow-up was linked to lower left than right frontal EEG activity at baseline, a pattern that replicated when first accounting for depressive symptoms at baseline. Despite the modest sample size of the present analysis, findings are consistent with prior reports of sex differences in patterns of brain laterality and support the idea that CSD-referenced EEG asymmetry may be a risk marker for future depression in previously healthy young women.

Depression and pain: testing of serial multiple mediators

PURPOSE

Despite the fact that pain is related to depression, few studies have been conducted to investigate the variables that mediate between the two conditions. In this study, the authors explored the following mediators: cognitive function, self-sacrificing interpersonal problems, and perception of stress, and the effects they had on pain symptoms among patients with depressive disorders.

PARTICIPANTS AND METHODS

An analysis was performed on the data of 346 participants with unipolar depressive disorders. The 17-item Hamilton Depression Rating Scale, Mini-Mental State Examination, the pain subscale of the health-related quality of life (SF-36), the self-sacrificing subscale of the Inventory of Interpersonal Problems, and the Perceived Stress Scale were used. Parallel multiple mediator and serial multiple mediator models were used. An alternative model regarding the effect of self-sacrificing on pain was also proposed.

RESULTS

Perceived stress, self-sacrificing interpersonal style, and cognitive function were found to significantly mediate the relationship between depression and pain, while controlling for demographic variables. The total effect of depression on pain was significant. This model, with an additional three mediators, accounted for 15% of the explained variance in pain compared to 9% without mediators. For the alternative model, after controlling for the mediators, a nonsignificant total direct effect level of self-sacrificing was found, suggesting that the effect of self-sacrificing on pain was based only on an indirect effect and that perceived stress was found to be the strongest mediator.

CONCLUSION

Serial mediation may help us to see how depression and pain are linked and what the fundamental mediators are in the chain. No significant, indirect effect of self-sacrificing on pain was observed, if perceived stress was not part of the depression and/or cognitive function mediational chain. The results shown here have implications for future research, both in terms of testing the model and in clinical application.

Treatment characteristics and outcome of depression among depressed adolescent outpatients with and without comorbid Axis II disorders

In the literature, disagreement exists on the impact of Axis II comorbidity on the treatment outcome of depression. The aim of the present study was to examine in a naturalistic treatment setting the 1-year outcome and treatment characteristics of depressed adolescent outpatients with and without comorbid Axis II disorders. The 151 participants were interviewed for Axis I and II diagnoses at baseline and follow-up. Those diagnosed with a personality disorder were significantly more impaired at follow-up than those without. The given treatment did not differ between the two groups in length, intensity, or hospitalization, but the group with Axis II comorbidity received more psychotropic medication. The treatment outcome of depression was poorer for the group with Axis II disorders compared to those without. In conclusion, a personality disorder diagnosis is a sign of more severe overall symptoms. Special attention should be paid to Axis II traits when planning and conducting the treatment of adolescent depression.

The effects of co-morbidity in defining major depression subtypes associated with long-term course and severity

BACKGROUND

Although variation in the long-term course of major depressive disorder (MDD) is not strongly predicted by existing symptom subtype distinctions, recent research suggests that prediction can be improved by using machine learning methods. However, it is not known whether these distinctions can be refined by added information about co-morbid conditions. The current report presents results on this question.

METHOD

Data came from 8261 respondents with lifetime DSM-IV MDD in the World Health Organization (WHO) World Mental Health (WMH) Surveys. Outcomes included four retrospectively reported measures of persistence/severity of course (years in episode; years in chronic episodes; hospitalization for MDD; disability due to MDD). Machine learning methods (regression tree analysis; lasso, ridge and elastic net penalized regression) followed by k-means cluster analysis were used to augment previously detected subtypes with information about prior co-morbidity to predict these outcomes.

RESULTS

Predicted values were strongly correlated across outcomes. Cluster analysis of predicted values found three clusters with consistently high, intermediate or low values. The high-risk cluster (32.4% of cases) accounted for 56.6-72.9% of high persistence, high chronicity, hospitalization and disability. This high-risk cluster had both higher sensitivity and likelihood ratio positive (LR+; relative proportions of cases in the high-risk cluster versus other clusters having the adverse outcomes) than in a parallel analysis that excluded measures of co-morbidity as predictors.

CONCLUSIONS

Although the results using the retrospective data reported here suggest that useful MDD subtyping distinctions can be made with machine learning and clustering across multiple indicators of illness persistence/severity, replication with prospective data is needed to confirm this preliminary conclusion.

Treatment Characteristics and Outcome of Depression Among Depressed Adolescent Outpatients With and Without Comorbid Axis II Disorders

In the literature, disagreement exists on the impact of Axis II comorbidity on the treatment outcome of depression. The aim of the present study was to examine in a naturalistic treatment setting the 1-year outcome and treatment characteristics of depressed adolescent outpatients with and without comorbid Axis II disorders. The 151 participants were interviewed for Axis I and II diagnoses at baseline and follow-up. Those diagnosed with a personality disorder were significantly more impaired at follow-up than those without. The given treatment did not differ between the two groups in length, intensity, or hospitalization, but the group with Axis II comorbidity received more psychotropic medication. The treatment outcome of depression was poorer for the group with Axis II disorders compared to those without. In conclusion, a personality disorder diagnosis is a sign of more severe overall symptoms. Special attention should be paid to Axis II traits when planning and conducting the treatment of adolescent depression.

Stressful life events, perceived stress, and 12-month course of geriatric depression: direct effects and moderation by the 5-HTTLPR and COMT Val158Met polymorphisms

Although the relation between stressful life events (SLEs) and risk of major depressive disorder is well established, important questions remain about the effects of stress on the course of geriatric depression. Our objectives were (1) to examine how baseline stress and change in stress is associated with course of geriatric depression and (2) to test whether polymorphisms of serotonin transporter (5-HTTLPR) and catechol-O-methyltransferase (COMT Val158Met) genes moderate this relation. Two-hundred and sixteen depressed subjects aged 60 years or older were categorized by remission status (Montgomery-Asberg depression rating scale≤6) at 6 and 12 months. At 6 months, greater baseline numbers of self-reported negative and total SLEs and greater baseline perceived stress severity were associated with lower odds of remission. At 12 months, only baseline perceived stress predicted remission. When we examined change in stress, 12-month decrease in negative SLEs and level of perceived stress were associated with improved odds of 12-month remission. When genotype data were included, COMT Val158Met genotype did not influence these relations. However, when compared with 5-HTTLPR L/L homozygotes, S allele carriers with greater baseline numbers of negative SLEs and with greater decrease in negative SLEs were more likely to remit at 12 months. This study demonstrates that baseline SLEs and perceived stress severity may influence the 12-month course of geriatric depression. Moreover, changes in these stress measures over time correlate with depression outcomes. 5-HTTLPR S carriers appear to be more susceptible to both the effects of enduring stress and the benefit of interval stress reduction.

The five factor model of personality in mixed anxiety-depressive disorder and effect on therapeutic response

INTRODUCTION

Patients with mixed anxiety and depressive disorder suffer the sub-threshold depressive and anxiety symptoms and their negative impact upon quality of life. This study evaluates their personality dimensions and the possible effect on treatment outcome.

METHODS

The diagnosis of mixed anxiety and depressive disorder was based on a structured clinical interview in 80 patients. NEO inventory measured five personality dimensions. The depression, anxiety and stress scale (DASS) was used to measure the severity of illness before and after the treatment.

RESULTS

Neuroticism, disagreeableness and introversion traits were significantly more expressed among these patients compared to normal population. A significant decrease in the score of depression, anxiety and stress was observed in all patients receiving the treatment. The normalized T-score of the five personality dimensions could not predict the degree of the response to treatment.

CONCLUSIONS

This study describes the personality characteristics of patients with mixed anxiety and depressive disorder and beneficial effects of treatment of such patients to be independent from personality dimensions.

Cognition and depression: the effects of fluvoxamine, a sigma-1 receptor agonist, reconsidered

Cognitive impairment is a primary feature of patients with major depressive disorder (MDD) and is characterised by stress-induced neural atrophy. Via alpha-adrenergic, anti-cholinergic and anti-histaminic activities, several antidepressants can cause significant counter-therapeutic cognitive impairment. Evidence is emerging of the involvement of sigma-1 receptor agonism in the mechanism of action of some antidepressants, notably fluvoxamine. Sigma-1 receptors are abundant in areas affected by depression/stress-induced cerebral atrophy and their ligands have a unique pharmacological profile; they may promote neurogenesis and initiate adaptive neural plasticity as a protection/reaction to stress. Fluvoxamine, as a potent sigma-1 receptor agonist, has shown ameliorating effects in animal models of psychosis, depression, stress, anxiety, obsessive-compulsive disorder (OCD) and aggression and has been shown to improve cognitive impairments. In humans, fluvoxamine may repair central nervous system (CNS) atrophy and restore cognitive function. The current review explores the mechanisms through which sigma-1 receptors can modulate cognitive function and examines how antidepressant therapy with fluvoxamine may help improve cognitive outcomes in patients with depression.

A new paradigm for the prediction of antidepressant treatment response

Current treatment of Major Depressive Disorder utilizes a trial-and-error sequential treatment strategy that results in delays in achieving response and remission for a majority of patients. Protracted ineffective treatment prolongs patient suffering and increases health care costs. In addition, long and unsuccessful antidepressant trials may diminish patient expectations, reinforce negative cognitions, and condition patients not to respond during subsequent antidepressant trials, thus contributing to further treatment resistance. For these reasons, it is critical to identify reliable predictors of antidepressant treatment response that can be used to shorten or eliminate lengthy and ineffective trials. Research on possible endophenotypic as well as genomic predictors has not yet yielded reliable predictors. The most reliable predictors identified thus far are symptomatic and physiologic characteristics of patients that emerge early in the course of treatment. We propose here the term “response endophenotypes” (REs) to describe this class of predictors, defined as latent measurable symptomatic or neurobiologie responses of individual patients that emerge early in the course of treatment, and which carry strong predictive power for individual patient outcomes. Use of REs constitutes a new paradigm in which medication treatment trials that are likely to be ineffective could be stopped within 1 to 2 weeks and other medication more likely to be effective could be started. Data presented here suggest that early changes in symptoms, quantitative electroencephalography, and gene expression could be used to construct effective REs. We posit that this new paradigm could lead to earlier recovery from depressive illness and ultimately produce profound health and economic benefits.

Select comorbid personality disorders and the treatment of chronic depression with nefazodone, targeted psychotherapy, or their combination

BACKGROUND

Individuals with chronic depression respond poorly to both medication and psychotherapy. The reasons for the poorer response, however, remain unclear. One potential factor is the presence of comorbid Axis II personality disorders (PDs), which occur at high rates among these patients.

METHODS

This study examines the moderating influence of co-occurring PDs, primarily in cluster C, among 681 chronically depressed adult outpatients who were randomly assigned to 12 weeks of treatment with nefazodone, a specialized psychotherapy for chronic depression, or their combination.

RESULTS

At baseline, 50.4% (n=343) of patients met criteria for one or more Axis II disorders. Following 12 weeks of treatment, patients with comorbid PDs had statistically lower depression scores (M=12.2, SD=+9.2) than patients without comorbid PDs (M=13.5, SD=+8.7). There was no differential impact of a comorbid PD on responsiveness to medication versus psychotherapy. The results did not change when the data were analyzed using an intent-to-treat sample or when individual personality disorders were examined separately.

LIMITATIONS

Patients with severe borderline, antisocial, and schizotypal PDs were excluded from study entry; therefore, these data primarily apply to patients with cluster C PDs and may not generalize to other Axis II conditions.

CONCLUSIONS

Comorbid Axis II disorders did not negatively affect treatment outcome and did not differentially affect response to psychotherapy versus medication. Treatment formulations for chronically depressed patients with certain PDs may not need to differ from treatment formulations of chronically depressed patients without co-occurring PDs.

Initial Treatment Success Followed By Failure

This article presents a diagnostically complicated case involving comorbid major depressive disorder with psychotic features, social phobia and personality pathology (including avoidant, paranoid, and obsessive compulsive traits). “Mr. X” was a 45-year-old single White male who was unemployed and living with his parents at the time of treatment. He presented with severe anxiety (Beck Anxiety Inventory = 43) and depression (Beck Depression Inventory = 41) as well as active psychotic symptoms (e.g., self-depreciating auditory hallucinations). Although a cognitive case formulation and treatment plan led to initial success in terms of improvements in symptomatology and functional impairment, we speculate that failure to adequately address core toxic beliefs (e.g., “I am inadequate”) ultimately contributed to a precipitous return of symptomatology, followed by a suicide attempt and premature treatment termination. We discuss the challenges of working within a cognitive framework with this client and suggest alternative approaches that might have proven more successful.

The heritability of hedonic capacity and perceived stress: a twin study evaluation of candidate depressive phenotypes

BACKGROUND

Anhedonia and stress sensitivity have been identified as promising depressive phenotypes. Research suggests that stress-induced anhedonia is a possible mechanism underlying the association between stress and depression. The present proof-of-concept study assessed whether hedonic capacity and stress perception are heritable and whether their genetic and environmental contributions are shared.

METHOD

Twenty monozygotic (MZ) and 15 dizygotic (DZ) twin pairs completed a probabilistic reward task that provides an objective behavioral measure of hedonic capacity (reward responsiveness) and completed several questionnaires including the Perceived Stress Scale (PSS). Bivariate Cholesky models were used to investigate whether covariation between (1) depressive symptoms and hedonic capacity, (2) depressive symptoms and perceived stress, and (3) perceived stress and hedonic capacity resulted from shared or residual genetic and environmental factors.

RESULTS

Additive genetic (A) and individual-specific environment (E) factors contributed to 46% and 54% of the variance in hedonic capacity, respectively. For perceived stress, 44% and 56% of the variance was accounted for by A and E factors, respectively. The genetic correlation between depression and hedonic capacity was moderate (ra=0.29), whereas the correlation between depression and stress perception was large (ra=0.67). Genetic and environmental correlations between hedonic capacity and stress perception were large (ra=0.72 and re=-0.43).

CONCLUSIONS

The present study provides initial feasibility for using a twin approach to investigate genetic contributions of a laboratory-based anhedonic phenotype. Although these preliminary findings indicate that hedonic capacity and perceived stress are heritable, with substantial shared additive genetic contributions, replications in larger samples will be needed.

Common genetic, clinical, demographic and psychosocial predictors of response to pharmacotherapy in mood and anxiety disorders

The aim of this study is to summarize available knowledge about common genetic, clinical, demographic and psychosocial predictors of response to pharmacotherapy in mood and anxiety disorders. A literature search was carried out by using MEDLINE and references of selected articles. The search included articles published up to March 2008. The main genetic finding concerns the serotonin transporter gene promoter polymorphisms, the long variant of which seems to be related to a positive response to therapy in mood disorders and could also have a role in the treatment of anxiety disorders. Among other predictors, the main factors common to both classes of disorder are comorbid axis II disorders and early onset of illness, which are related to a worse response to therapy and concomitant good physical conditions, absence of earlier treatments, early administration and response to therapies, and higher self- directedness, which is related to a better outcome. Many common predictors have been identified and these seem to be related to features covering the totality of patients that go beyond specific characteristics of single disorders. Possible limitations and suggestions for future research based on a more integrated vision of human complexity are discussed.