Disentangling the Link Between Mindfulness and Dissociation in PTSD: The Mediating Role of Attention and Emotional Acceptance.

INTRODUCTION: A number of studies have investigated the relationship between mindfulness and dissociation and suggested that mindfulness-based interventions could be effective in the treatment of dissociative symptoms. A recent study in healthy volunteers found that attention and emotional acceptance mediates this relationship. However, no study has yet been performed among a clinical sample to assess this association. METHOD: We recruited 90 patients (76 women) suffering from Posttraumatic Stress Disorder (PTSD). They completed self-report questionnaires to measure PTSD, dissociation, emotion regulation difficulties, childhood trauma, mindfulness abilities and cognitive abilities. RESULTS: We found that mindfulness abilities, emotional difficulties, dissociation and attention-concentration were all related to each other. Using a step-by-step approach and bootstrapping techniques, we found a significant indirect effect of mindfulness abilities on dissociation through non-acceptance (confidence interval 95%=-.14 to -.01) and attentional difficulties (confidence interval 95%=-.23 to -.05). CONCLUSION: Patients with higher levels of dissociative symptoms have less capacity for mindfulness. Our results support Bishop et al.'s model proposing that attention and emotional acceptance are the two active components of mindfulness. To extend our findings, clinical trials are required to evaluate a causal relationship and the effectiveness of mindfulness-based interventions for patients suffering from dissociation.

Interaction of mediation and moderation effects of positivity, cognitive fusion, brooding and mindfulness.

INTRODUCTION: Currently, cognitive behavior therapy (CBT) targets multiple cognitive processes. However, only a few studies have focused on the interaction among these processes. Preliminary studies have identified a moderation effect of rumination on the link between thought content and emotional difficulties, and a mediation effect of ruminations on the link between mindfulness and emotional difficulties. METHOD: We recruited 236 participants (185 women) who consented online to participate by choosing to either continue with the study or decline to proceed. They completed a battery of questionnaires online, namely Positivity scale, General Health Questionnaire, Rumination Response Scale, Five Facet Mindfulness Questionnaire and Cognitive Fusion Questionnaire. RESULTS: All cognitive processes were significantly correlated with emotional distress. Step-by-step linear regression analysis revealed that positivity, cognitive fusion and brooding were significant independent predictors of emotional difficulties. Bootstrapping analysis confirmed that cognitive fusion and brooding mediate the link between mindfulness and depression and anxiety-insomnia. They also demonstrated that cognitive fusion moderates the link between positivity and depression but not anxiety-insomnia. CONCLUSION: Cognitive processes interact with each other. Taken together, these results suggest that combining cognitive interventions is not useful and that different cognitive interventions may be selected depending on the patient's profile.

[GABAergic approach of postpartum depression: A translational review of literature]. / Approche GABAergique de la dépression du post-partum : une revue critique translationnelle.

INTRODUCTION: Prevalence of postpartum depression (PPD) ranges from 10 to 15 % of parturients. The impact of the PPD is major on the maternal bond and the health of both mother and child. Its physiopathological mechanisms appear to differ from other types of depression. Today, pharmacotherapy is based on nonspecific treatment, and recent therapeutic advances in this field require a comprehensive approach of the implication of the GABAergic system in the development of PPD. Neurosteroid levels during pregnancy and after parturition and the GABA-A-r modulation are thought to be involved in PPD. OBJECTIVE: To evaluate if the GABAergic approach is relevant in postpartum depression management. METHODS: We conducted a systematic review of literature based on the MEDLINE database with the following Medical Subject Headings (MeSH): "postpartum depression", "GABA", "ganaxolone", "brexanolone", "allopregnanolone", prior to September 2019. We selected articles in English: preclinical and clinical studies, literature review, observational and therapeutic studies. RESULTS: Preclinical models (mouse and rat) show changes in GABAergic inhibition in the peripartum period and correlation between allopregnanolone and GABA-A-r plasticity. This plasticity in the peripartum period maintains levels of inhibition adapted despite increased neurosteroid levels. KO models for the GABA-A-r δ subunit develop depression and anxiety symptoms in the postpartum period, and a change in the expression of the gene coding for the GABA-R alpha-4 subunit was found. Artificial inhibition of progesterone metabolism during post-partum increased depression symptoms. GABAergic fluctuation seems to be interrelated with other systems such as those of oxytocins. A synthetic neurosteroid (SGE-516) was tested on mouse models of PPD, KO for δ-GABA-A-r or KCC2, and showed decreased depressive symptoms and better mothering. Clinical studies confirm neurosteroid fluctuation and changes in the GABAergic system during the peripartum period. Allopregnanolone is the neurosteroid the most studied in PPD, and it is elevated in the brain during the pregnancy. Studies disagree on the presence of significant differences in allopregnanolone plasma levels during pregnancy or postpartum between women with PPD or not. Women with a history of PPD have greater susceptibility to neurosteroid withdrawal. Imagery and genetical data also show a link between allopregnanolone and PPD. The GABA-A-r may not recover in time following a reduced number during pregnancy, and this mismatch between neurosteroid levels and their receptor may trigger PPD. Several randomized controlled trials investigated brexanolone administrated IV, a synthetic formulation of allopregnanolone, and demonstrated a rapid and well tolerated reduction in depressive symptoms. In March 2019 brexanolone obtained FDA approval in PPD indication under the name Zulresso. However, there are differences in the time of beginning of PPD, which could constitute different subgroups of this disease, and which physiopathology could respond to different mechanisms. Prenatal depression does not respond to a GABAergic approach, but women without any risk factor or previous mood disorder developing PPD in the weeks following childbirth could be particularly responsive to this kind of treatment. CONCLUSION: Disability to modulate GABA-A-r expression during pregnancy and restore its previous state after parturition appears to trigger PPD. The GABAergic system is a promising pharmacotherapy target. From preclinical to clinical studies for about twenty years the GABAergic system has been incriminated and targeted in this challenging mental disease.