Session-specific effects of the Metacognitive Group Training for Obsessive-Compulsive Disorder: significant results for thought control

The investigation of the session-specific effects is central for the understanding of psychological interventions. For the present study, we investigated the session-specific effects of the Metacognitive Group Training for Obsessive-Compulsive Disorder (MCT-OCD), which was revised based on data of a pilot study. Thirty-four outpatients with OCD participated in the MCT-OCD once a week over 8 weeks. Different metacognitive beliefs (e.g., thought control) and cognitive beliefs (e.g., intolerance of uncertainty), OC symptoms, as well as associated comorbid symptoms were assessed before and after each session. Linear mixed effects models showed that patients' obsessions and compulsions, thought control, the belief of being well informed about the disorder, and action fusion improved over the course of the training. The only session-specific effect emerged for thought control, which improved immediately after the respective module. We were able to replicate the findings of the pilot study and thus corroborate the session-specific effect of the module targeting thought control. Moreover, we generated information on the mode of action of the individual modules of the MCT-OCD that allows a more in-depth evaluation of the intervention. Notably, we were able to eliminate the adverse effects of the pilot version of the MCT-OCD.Trial Registration: German Clinical Trials Register (Deutsches Register Klinischer Studien [DRKS];DRKS-ID: DRKS00013539;registration date: 22/02/2018)

Inverse autonomic stress reactivity in depressed patients with and without prior history of depression

Background: There is a considerable association between major depressive disorder (MDD) and cardiovascular disease, most possibly relying on abnormalities in the autonomic nervous system (ANS)-related cardiac reactivity, although the exact underlying pathophysiological pathway is unclear. This study tends to shed some additional light on this background by investigating ANS reactivity in MDD with respect to previous depression history through an objective stress challenge paradigm. Methods: The study assessed the effects of an overnight hypothalamus-pituitary-adrenal (HPA) axis stimulation with metyrapone (MET) on baseline ANS activity through linear and non-linear heart rate variability (HRV) measures in the morning of two continuous days in a group of 14 physically healthy, antidepressant-free patients with clinical, non-psychotic MDD, to investigate differences in autonomic reactivity with respect to prior MDD history. Results: The main findings of this study include statistically significant time × group interactions with respect to several HRV measures, suggesting substantial differences on autonomic reactivity between patients with and without depression history. Hereby, recurrent-episode MDD patients showed lower vagal activity, while first-episode MDD patients increased PNS activity after HPA axis stimulation. Conclusions: These findings indicate that HPA axis stimulation in MDD patients leads to inverse vagal response according to MDD history. We suggest that chronic stress system overactivation, as found in MDD, might lead to a progressive inversion of the original stress response through HPA axis and ANS divergence over the course of a recurrent illness. HRV could, thus, represent a significant biomarker in MDD with temporal sensitivity