Mechanisms of mindfulness: a longitudinal study of a Mindfulness-Based Stress Reduction program

Objectives: This study sought to identify the temporal order in which mindfulness facets develop during Mindfulness-Based Stress Reduction (MBSR) and the effect of early changes on later changes in these facets and their relation to changes in depression, anxiety, and stress. Methods: This longitudinal study of 147 adults participating in a MBSR program examined relationships between components of mindfulness, self-compassion and measures of depression, anxiety, and stress. Self-report measures were administered pre-course, mid-course, end-of-course, and 3-months post-course. Results: Initial improvements in decentering, non-reactivity, and self-compassion were observed early in the MBSR course (p-values < 0.05), followed by later changes in observing, acting with awareness, and nonjudging. Bivariate latent growth curve modelling suggested changes in the mindfulness components of decentering and nonreactivity coincided with decreases in anxiety and stress (p-values < 0.05). However, in a path analysis, changes in self-compassion appeared to uniquely contribute to changes in depression and anxiety, over and above the effects of other mindfulness components (p-values < 0.05). These changes in self-compassion were associated with simultaneous and precursory change in non-reactivity and non-judgment. Conclusions: These findings elucidate the possible temporal order of change in mindfulness facets through MBSR. Self-compassion may be a prominent mechanism of change in the MBSR program, along with non-reactivity and decentering. However, additional longitudinal research is needed with alternate model specifications to confirm the proximal role of self-compassion in longitudinal symptom change. Results are tempered by a relatively short period of longitudinal observation with a possible nonresponse bias. Preregistration: Because the trial was conceived prior to 2009, pre-registration was not possible. However, the trial was registered on anzctr.org.au after data collection and analysis. [Title: “Mechanisms of mindfulness: A longitudinal observational study of the effects of mindfulness-based stress reduction (MBSR) on depression, anxiety, and stress among participants in a MBSR program”, Identifier: ACTRN12623000485639].