How does emotion regulation change during psychotherapy? A daily diary study of adults in a transdiagnostic partial hospitalization program.

Improvement in emotion regulation is a proposed transdiagnostic mechanism of change. However, treatment research is limited by disorder-specific investigations that assess a narrow number of emotion regulation strategies. Moreover, most assess pre-to-post-treatment change without examining short-term changes throughout psychotherapy that might influence treatment response.To address these gaps, this study uses daily diary methodology to examine trajectories of change in use of six emotion regulation strategies during partial hospitalization psychiatric treatment. Treatment was rooted in cognitive behavioral principles and included skills adapted from empirically supported cognitive behavioral therapy (CBT) and dialectical behavior therapy (DBT) manuals. Participants were adults (N = 364; Mage = 34.6 years; 60% female; 85% non-Hispanic White) with various profiles of mood, anxiety, and obsessive-compulsive disorders who completed symptom measures at baseline and discharge and daily measures of emotion regulation.In the first 7 treatment days, patients increased use of engagement strategies (reappraisal, acceptance) and decreased use of disengagement (expressive suppression) and cognitive perseveration (experiential avoidance, rumination) strategies. Day-to-day trajectories found that decreased use of experiential avoidance predicted next-day changes in distraction and suppression use. In predicting treatment outcomes, steeper rates of decreased suppression use predicted reductions in anxiety, depression, and general psychopathology symptoms; similar patterns were observed for decreased rumination and experiential avoidance use and increased reappraisal use.Results add to a growing literature on the value of intentional, constructive engagement with emotional experiences as a mechanism of psychological health. (PsycInfo Database Record (c) 2023 APA, all rights reserved).