Standardized stress reduction interventions and blood pressure habituation: Secondary results from a randomized controlled trial.

Meta-analyses suggest a small association between cardiovascular responses to acute stressors and cardiovascular disease, but a recent review suggests that this effect may be underestimated due to insufficient consideration of individual differences in habituation to repeated stressors. OBJECTIVE: The present article reports new analyses of a published randomized controlled trial comparing the effects of mindfulness-based stress reduction (MBSR), cognitive behavioral therapy (CBT), and a passive control condition on blood pressure habituation-a secondary outcome. Psychological mediators of intervention effects were examined. METHOD: Participants (138 healthy adults reporting moderate/high stress) were randomly assigned to 6-week MBSR, CBT, or a waitlist control. Analyses were conducted on 86 participants who subsequently completed stressful speech and mental arithmetic tasks during two posttreatment visits scheduled 48 hr apart. Blood pressure was measured -15, +0, +5, +10, +25, +35, and +60 min poststressor onset. RESULTS: There were no between-condition differences in blood pressure habituation (all ps > .05). However, both MBSR and CBT led to increased perceived control over thoughts, F(2, 72) = 5.20, p = .008, and individuals who displayed a greater change in perceived control over thoughts also displayed greater habituation to the speech portion of the stressor, F(6, 799) = 2.32, p = .020. Results implied an indirect effect of stress reduction interventions on blood pressure habituation via change in perceived control over thoughts (b = -3.93, SE = 1.98, 95% CI: [-8.392, -0.701]). CONCLUSION: Stress reduction interventions that increase perceived control over thoughts may benefit cardiovascular health by promoting blood pressure habituation. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

When enhanced awareness threatens: Interactive effects of domain-specific awareness and acceptance manipulations on cardiovascular indices of challenge and threat.

Mindfulness includes acceptance and awareness subcomponents, and emerging theories imply that cultivating both acceptance and awareness may benefit health by diminishing stress reactivity. Yet, no prior work has examined the effects of mindful acceptance and awareness on cardiovascular markers of threat and challenge-cardiac output and total peripheral resistance-despite the unique insights these indices yield into stress-related evaluations and motivation. The current research integrates Monitor and Acceptance Theory with the Biopsychosocial Model of Challenge and Threat to elucidate how an awareness manipulation and a brief acceptance training are associated with cardiovascular stress responses underlying states of challenge and threat. Healthy young adults (N = 202) were enrolled in a 2 × 2 between-subjects experimental design manipulating both awareness (enhanced awareness vs. no enhanced awareness) and acceptance (acceptance training vs. no acceptance training) of physiological responses to a social-evaluative cold pressor test. Cardiovascular indices were recorded throughout. The combination of enhanced awareness and acceptance training led to higher cardiac output and lower total peripheral resistance (indexing greater challenge, less threat) to the cold pressor test than the combination of enhanced awareness and no acceptance training. However, the combination of no enhanced awareness and no acceptance training also led to higher cardiac output and lower total peripheral resistance than the combination of enhanced awareness and no acceptance training. These results add to a growing body of work suggesting that mindful awareness and acceptance subcomponents interact to influence stress reactivity and imply that enhanced stressor awareness without acceptance may lead to increased threat.

Cognitive behavioral therapy, mindfulness, and cortisol habituation: A randomized controlled trial.

BACKGROUND: Hypothalamic-pituitary-adrenocortical (HPA) axis dysregulation is associated with disease and may be indexed by poor cortisol habituation (i.e., a failure to show decreased responding with repeated stressor exposure). Thus, stress management training that can enhance HPA axis habituation may benefit health. To date, the effects of Mindfulness Based Stress Reduction (MBSR) and Cognitive Behavioral Therapy (CBT) interventions on HPA axis habituation remain untested. To test the effects of MBSR and CBT on HPA axis habituation, the present study used a parallel arm randomized controlled trial. METHODS: Healthy adults reporting moderate-to-high stress (n = 138) were randomly assigned to a 6-week MBSR intervention, a 6-week CBT intervention, or Waitlist control group. Post-intervention, participants completed a social-evaluative performance stressor during each of two laboratory visits scheduled 48-h apart. Salivary cortisol was collected pre-stressor, and 25, 35, and 60 min post-stressor onset during each visit. Final analyses included 86 participants who completed procedures up to the first laboratory visit. RESULTS: Relative to the control condition, both MBSR and CBT groups showed greater cortisol habituation. The MBSR group exhibited marginally greater habituation than the Waitlist group in cortisol samples corresponding to the recovery time points (35 and 60 min post-stressor onset). In contrast, the CBT group showed greater habituation than the Waitlist across all sampling timepoints collected (pre-stressor, 25, 35, and 60 min post-stressor onset). Yet, the CBT group also demonstrated elevated pre-stressor cortisol during the first visit. CONCLUSIONS: Results suggest that MBSR and CBT interventions promote greater HPA axis habituation relative to no training, but do not reduce overall cortisol output (i.e., across both visits). Observed differences between CBT and MBSR training in relation to cortisol habituation are discussed.

Trait mindfulness predicts the presence but not the magnitude of cortisol responses to acute stress.

BACKGROUND: Mindfulness, or the practice of observing present moment experiences with acceptance, is thought to improve health at least partially by limiting hypothalamic-pituitary-adrenal (HPA) axis over-responsiveness during episodes of acute stress. However, models of allostatic load suggest that HPA axis under-responsiveness can also be detrimental to health, and the relationship between mindfulness and cortisol under-responsiveness has yet to be examined. The present study therefore aimed to address this knowledge gap, and to revisit the relationship between mindfulness and acute cortisol response magnitude while excluding (or statistically controlling for) individuals displaying HPA axis under-responsiveness. METHODS: Participants (124 healthy undergraduate students) were subjected to a stressful speech task, and completed a trait mindfulness questionnaire. Salivary cortisol was collected 0, +15, +25, +40, and +55 min post-stressor onset. RESULTS: Greater trait mindfulness was associated with greater odds of displaying a cortisol response relative to none, but was unrelated to the magnitude of cortisol responses among those who displayed an acute response. CONCLUSIONS: In the present sample, trait mindfulness was associated with cortisol responses, but this was driven by the fact that subjects low in mindfulness were more likely to be non-responders. Contrasting the effects of mindfulness on the presence (i.e., present vs. absent) and the degree (i.e., magnitude) of acute stress responses may therefore be warranted in future research.