A comparison of mindfulness-based stress reduction and an active control in modulation of neurogenic inflammation

Abstract

Psychological stress is a major provocative factor of symptoms in chronic inflammatory conditions. In recent years, interest in addressing stress responsivity through meditation training in health-related domains has increased astoundingly, despite a paucity of evidence that reported benefits are specific to meditation practice. We designed the present study to rigorously compare an 8-week Mindfulness-Based Stress Reduction (MBSR) intervention to a well-matched active control intervention, the Health Enhancement Program (HEP) in ability to reduce psychological stress and experimentally-induced inflammation. The Trier Social Stress Test (TSST) was used to induce psychological stress and inflammation was produced using topical application of capsaicin cream to forearm skin. Immune and endocrine measures of inflammation and stress were collected both before and after MBSR training. Results show those randomized to MBSR and HEP training had comparable post-training stress-evoked cortisol responses, as well as equivalent reductions in self-reported psychological distress and physical symptoms. However, MBSR training resulted in a significantly smaller post-stress inflammatory response compared to HEP, despite equivalent levels of stress hormones. These results suggest behavioral interventions designed to reduce emotional reactivity may be of therapeutic benefit in chronic inflammatory conditions. Moreover, mindfulness practice, in particular, may be more efficacious in symptom relief than the well-being promoting activities cultivated in the HEP program.

Copyright © 2012 Elsevier Inc. All rights reserved.

Figures

Figure 1

An illustration of the experimental design and timing of the collection of the outcome measures.

Figure 2

Raw cortisol data showing (a) response to the TSST and (b) diurnal cortisol rhythm for each group at each assessment.

Figure 3. Blister fluid cytokine and salivary cortisol response to capsaicin application and stress

(a) Increases in blister fluid TNF-α from pre to post-challenge at T1 (t(46) = −8.09, p < .001), T2 (t(42) = −8.89, p < .001), and T3 (t(46) = −12.00, p < .001). (b) Increases in blister fluid IL-8 from pre- to post-challenge at T1 (t(41) = −6.33, p < .001), T2 (t(41) = −7.99, p < .001) and T3 (t(44) = −10.54, p < .001). (c). Increases in salivary cortisol from pre- to post-challenge at T1 (t(47) = −6.01, p < .001), T2 (t(42) = −4.21, p < .001), and T3 (t(45) = −4.73, p < .001). Error bars represent standard error of the mean.

Figure 4. Effects of intervention and time on flare size

Flare size increased significantly from T1 to T2 (F(1, 27) = 31.74, p < .001). In addition, a significant group × time interaction was observed (F(1, 27) = 10.07, p = .004), such that mean flare size for the HEP group at T2 was larger than that of the MBSR group. Error bars represent standard error of the mean.

Figure 5. Relationship between practice and blister fluid cytokine changes from pre- to post-intervention differs by group

We observed interactions between group and practice in relation to blister fluid cytokine levels (TNF-α: sr = −.35, p = .028; IL-8: sr = −.17, p = .334). In the MBSR group (red), number of minutes practiced during the 8-wk intervention is (non-significantly) negatively correlated with the reduction in blister fluid (a) TNF-α (MBSR: r = −.28, p = .16; HEP: r = .42, p = .12) and (b) IL-8 levels (MBSR: r = −.20, p = .33; HEP: r = .17, p = .59) from T1 to T2, whereas these relationships are positive for the HEP group (green).