Role of autobiographical memory in the impact of MBCT on dysfunctional attitudes, depressive symptoms and anxiety in bipolar I patients

Active components and mechanisms of action of psychological interventions in bipolar disorder: A systematic literature review

OBJECTIVE

The efficacy of psychological interventions for bipolar disorder (BD) is well established, but much remains unknown about how change occurs. The primary objective of this exploratory study was to audit what is known about active components and mechanisms of action of psychological interventions for BD.

METHOD

We conducted a systematic review (PROSPERO CRD42022323276). Two independent reviewers screened references from four databases and extracted data from eligible studies.

RESULTS

We included four component studies, six studies with mediation analyses and 26 studies presenting subjective experiences of how psychological interventions bring change. Ten mediators were examined across six studies, with only one putative mediator, medication adherence, tested in more than one study. Some initial support for mediation of varied outcomes by control over thoughts, positive non-verbal behaviour, self-esteem, post-trauma growth and medication adherence. Some preliminary support was found in two components, human support and IPT. Studies exploring participant experiences of therapeutic change enumerated a range of potential active components, mechanisms of action and contextual factors potentially warranting investigation in future research. However, the evidence base for active components and mechanisms of action in psychological interventions for BD is unsatisfactory. Findings were inconsistent, studies homogenous with significant methodological limitations and statistical approaches failed to meet quality criteria.

CONCLUSIONS

Preliminary identification of potential components and mechanisms via qualitative analyses and the insights emerging from this review will inform future research aimed at investigating how psychological interventions work in BD.

Are dysfunctional attitudes elevated and linked to mood in bipolar disorder? A systematic review and meta-analysis

OBJECTIVES

Dysfunctional attitudes (DA) are higher in depression; however, less is understood about their role in bipolar disorder (BD). This paper aimed to explore the presence of DA in BD in comparison to clinical and non-clinical groups. Also explored were the associations between DA and mood states of depression, mania or euthymia in BD.

METHODS

A systematic review and meta-analysis were conducted. A total of 47 articles were included in the systematic review of which 23 were included in the meta-analysis. The quality of each study was rated.

RESULTS

The meta-analysis showed significantly higher DA in BD than healthy controls (d = .70). However, no difference was observed between BD and unipolar participants (d = -.16). When reviewing mood state within BD, a significant mean difference was found between DA scores for euthymic and depressed participants (d = -.71), with those who were depressed scoring higher. Three studies found that psychological therapies significantly reduce DA in BD (d = -.38).

CONCLUSIONS

These findings imply not only that DA are both a characteristic of BD that is not as prevalent in healthy populations but also that a depressed mood state is associated with increased severity. This implies that DA could possibly go 'offline' when mood symptoms are not present. Psychological therapies appear to reduce DA in BD. Implications for future research as well as practice-based implications are expanded on in the discussion.

Do psychological interventions reduce symptoms of depression for patients with bipolar I or II disorder? A meta-analysis

BACKGROUND

Psychological therapies may play an important role in the treatment of bipolar disorders. Several meta-analyses that examine the effectiveness of psychotherapies for patients with bipolar disorder include conclusions about the impact upon bipolar depression. However, these tend not to consider differences in depression outcome depending upon whether the therapy primarily targets acute depression, nor severity of baseline depression. This may affect the conclusions drawn about the effectiveness of these therapies for acute bipolar depression treatment.

OBJECTIVES

This meta-analysis explored the effectiveness of psychological therapies in reducing bipolar depression, in particular examining whether: (1) the effect of therapy is greater when baseline depressive symptoms are more severe, and (2) the effect of therapy is greater when the primary focus of the therapy is the treatment of acute bipolar depression?

DATA SOURCES

A systematic search was conducted using the following electronic databases; Cochrane Controlled Register of Trials (1996), MEDLINE (1966 onwards), EMBASE (1980 onwards), PsycINFO (1974 onwards), Scopus, Web of Science and Clinical Trials Registries (listed at:https://www.hhs.gov/ohrp/international/clinical-trial-registries/index.html).

ELIGIBILITY CRITERIA

Eligible studies were randomized controlled trials evaluating a psychological intervention for adults diagnosed with Bipolar I or II disorder. The comparators were usual care, wait-list, placebo, active treatment control. Post-treatment depression status was required to be measured continuously using a validated self- or observer- report measure, or categorically by a validated diagnostic instrument or clinical diagnosis by a suitably qualified person.

DATA EXTRACTION AND SYNTHESIS

Titles and abstracts were screened, followed by full texts. Two reviewers conducted each stage until agreement was reached, and both independently extracted study information. Means, standard deviations (SDs) and number of participants were retrieved from articles and used to perform a meta-analysis. The primary outcome was depressive symptom score.

RESULTS

The database search identified 6388 studies. After removing the duplicates, 3298 studies remained, of which, 28 studies were included in the qualitative review and 22 in the meta-analysis. Effect sizes range from -1.99 [-2.50, -1.49] to 0.89 [-0.12, 1.90]. There was low quality evidence of a significant effect on symptoms of depression for cognitive behavioral therapy and dialectical behavior therapy. Trials of psychoeducation, mindfulness-based therapy, family therapy and interpersonal and social rhythm therapy showed no evidence of any effect on depression. We found no significant relationship between baseline depression score and depression outcome post-treatment when we controlled for therapy type and comparator. The result also showed that the effect sizes for studies targeting acute depression to be tightly clustered around a small overall effect size.

CONCLUSIONS

Some psychological therapies may reduce acute bipolar depression although this conclusion should be viewed with caution given the low quality of evidence. More research using similar therapy types and comparators is needed to better understand the relationship between depression status at baseline and outcome.

Emotional autobiographical memory impairment features in three mental disorders

We proposed the Emotional Autobiographical Memory Test (EAMT) as a specialized method for measuring emotional autobiographical memory impairment in patients with mental disorders. The EAMT was tested with 32 patients with schizophrenia, 18 patients with bipolar disorder, 32 patients with depression, and 42 people undiagnosed with such disorders. We extracted 13 indices of five kinds of features from participants' emotional autobiographical memory and compared them among the four groups. The overgeneralization result in the schizophrenia and depression groups was consistent with previous results, supporting the EAMT's validity. However, inconsistent with previous results, overgeneralization was not found in the bipolar disorder group. Further, the count of involuntary memories in the patient groups (vs. control group) was significantly smaller, which can guide future researchers in investigating the psychopathology of mental disorders.

From Self-Esteem to Selflessness: An Evidence (Gap) Map of Self-Related Processes as Mechanisms of Mindfulness-Based Interventions

Self-related processes (SRPs) have been theorized as key mechanisms of mindfulness-based interventions (MBIs), but the evidence supporting these theories is currently unclear. This evidence map introduces a comprehensive framework for different types of SRPs, and how they are theorized to function as mechanisms of MBIs (target identification). The evidence map then assesses SRP target engagement by mindfulness training and the relationship between target engagement and outcomes (target validation). Discussion of the measurement of SRPs is also included. The most common SRPs measured and engaged by standard MBIs represented valenced evaluations of self-concept, including rumination, self-compassion, self-efficacy, and self-esteem. Rumination showed the strongest evidence as a mechanism for depression, with other physical and mental health outcomes also supported. Self-compassion showed consistent target engagement but was inconsistently related to improved outcomes. Decentering and interoception are emerging potential mechanisms, but their construct validity and different subcomponents are still in development. While some embodied self-specifying processes are being measured in cross-sectional and meditation induction studies, very few have been assessed in MBIs. The SRPs with the strongest mechanistic support represent positive and negative evaluations of self-concept. In sum, few SRPs have been measured in MBIs, and additional research using well-validated measures is needed to clarify their role as mechanisms.

Mindfulness-based cognitive therapy efficacy in reducing physiological response to emotional stimuli in patients with bipolar I disorder and the intermediate role of cognitive reactivity

OBJECTIVES

This study aims to investigate the impact of Mindfulness-Based Cognitive Therapy (MBCT) for bipolar disorders on emotional responses by using skin conductance recording, and to investigate a mediating or predictive effect of cognitive reactivity.

METHODS

Sixty-seven patients with bipolar disorder were assessed at baseline, pre-MBCT and post-MBCT. After answering inventories regarding depression and dysfunctional attitudes, they were instructed to focus on emotional pictures from the International Affective Pictures System while electrodermal recording.

RESULTS

For a subgroup of patients having a significant change of the electrodermal response, MBCT reduced dysfunctional attitudes and the amplitude of the physiological response to negative stimuli. Findings also show that lower dysfunctional attitudes at baseline predicted a larger reduction of physiological reactivity.

CONCLUSIONS

MBCT could decrease patient's reactivity to negative stimuli by decreasing its physiological component, which is coherent with its aim to facilitate disengaging from affective stimuli. Further studies are needed to better understand the mechanisms involved and how this could translate in reducing the risk of relapse.