Differential Roles of Mindfulness and Thought Suppression In Posttraumatic Stress Symptoms and Substance Craving

Background: The present research provides an empirical test of a theoretical model of trauma, cognitive coping processes, and substance craving among persons diagnosed with substance dependence disorders. We propose that when individuals engage in thought suppression as a means of coping with traumatic life events, this form of experiential avoidance results in amplified symptoms of post-traumatic stress, which in turn promotes drug craving among individuals with a history of self-medicating trauma with psychoactive substances. In contrast, the adaptive psychological tendency of dispositional mindfulness, i.e., a mindset characterized by nonreactive awareness and acceptance of emotional experience, may serve as a protective factor and mitigate this pathogenic cycle underpinning the co-occurrence of trauma and addiction.

Methods: A sample of 125 individuals meeting DSM-IV criteria for one or more substance dependence diagnoses (mean age 38.7, SD = 10.0; 51.5% African American, 39.6% Caucasian; 92% male) completed a set of validated assessment instruments. The majority of study participants were dependent on either cocaine and/or alcohol, and on average, participants had experienced 5.3 different categories of traumatic life events (SD = 2.1). Path analysis tested relationships between trauma history, thought suppression, post-traumatic stress symptoms, and drug craving. Hierarchical regression analysis examined the differential roles of dispositional mindfulness and thought suppression as predictors of post-traumatic stress symptoms and drug craving.

Results: Regression analysis indicated that thought suppression, rather than extent of trauma history, significantly predicted post-traumatic stress symptom severity. Moreover, our conceptual model exhibited excellent empirical fit (chi square p value = .84, CFI = 1.00, RMSEA = .00) and all proposed path coefficients were statistically significant in the expected directions: prior traumatic experience was associated with greater thought suppression, which in turn was correlated with increased PTSD symptoms and drug craving. Furthermore, in hierarchical regression models, dispositional mindfulness and thought suppression combined explained nearly half of the variance in PTSD symptoms (Model R-squared = .46) and one-quarter of the variance in substance craving (Model R-squared = .25), and each factor accounted for unique portions of variance in these clinical outcomes.

Discussion: In an attempt to cope with the sequelae of traumatic life events, vulnerable individuals may resort to the maladaptive strategy of thought suppression, which inadvertently amplifies post-traumatic stress symptoms and depletes the self-regulatory resources needed to regulate substance cravings. Conversely, among substance dependent individuals with extensive trauma histories, dispositional mindfulness was associated with reduced post-traumatic stress and craving. Identification of malleable traits that can counter risk mechanisms implicated co-occurring disorders is of paramount importance to treatment development efforts.