Randomized Clinical Trial of a Mindfulness Based Intervention in Generalized Anxiety Disorder

The literature suggests that Mindfulness Based Intervention may be effective in the treatment of anxiety symptoms. The objective of this study is to compare the clinical effectiveness of a Mindfulness Based Intervention - the Mind in Body Training (MBT) - with a selective serotonin reuptake inhibitor (Fluoxetine) and an active control group (Quality of Life) through different biological and clinical outcomes, as well as evaluate some possible mechanisms of treatment response. Methods: it is a three armed randomized, controlled clinical trial. Participants with General Anxiety Disorder will be recruited. A community sample of 192 participants will be randomly allocated to the MBT, Fluoxetine or Quality of Life Group. Instruments measuring anxiety, worry and meta-worry symptoms, quality of life, acceptance and self-compassion, mindfulness, rumination and emotion regulation will be applied. The patients will be submitted to Error Related Negativity (ERN) and Heart Rate Variability (HRV) measures. The primary outcome is the effectiveness of MBT compared with Fluoxetine and Quality of Life Group in symptomatic outcomes. The secondary outcome are the effectiveness os these interventions in emotional regulation process and biological measures (ERN and HRV), and the evaluation of BMT mechanisms through possible mediation of treatment response for emotional processes like mindfulness, acceptance and self-compassion, biological changes (ERN and HRV), and metacognition.