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

Unlabelled: 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).