title: The effect of mindfulness-based stress reduction on biological markers of stress, immune function and cellular aging among breast cancer survivors with chronic neuropathic pain
Creators: name: Strong, Vanessa Dawn
Publisher: name: Memorial University of Newfoundland
Year: 2021

description: Background: Chronic neuropathic pain (CNP) is a common sequalae among breast cancer survivors. Nonpharmacological adjuvants are being increasingly recommended as first-line adjunct treatments for the management of CNP conditions which is consistent with a multidisciplinary biopsychological approach to optimize pain management. Mindfulness-based stress reduction (MBSR) is one of the most commonly applied mindfulness interventions in the treatment of CNP and has been shown to have preferential improvements in pain and overall health-related quality of life. Although mindfulness interventions have shown promise in the treatment of chronic illness and disease, it has yet to be studied in breast cancer survivors living with CNP after medical optimization. Thus, the effect of MBSR on CNP in this highly heterogenous and complex clinical population is unknown. Biological markers are objective measures of biological systems that can be used to gain insight into the mechanisms through which psychological interventions exert their effects. The aim of the first study was to use an interdisciplinary treatment approach to CNP in breast cancer survivors by exploring the effects of MBSR on pain, and biological markers of stress, immune function and cellular aging among breast cancer survivors with CNP after guideline-based medical optimization. A second study was conducted to explore the potential mediating role of mindfulness, and the individual facets, in this change process. Methods: A double-blind randomized waitlist control trial was conducted using a sample of 98 breast cancer survivors diagnosed with CNP. Women were randomized to receive an 8-week MBSR intervention or waitlist control condition after undergoing medical optimization. Biological samples and self-report measures of pain, physical function and emotional function were collected at baseline, two-weeks post-intervention and at 3-month follow-up. Separate analyses were performed using intention-to-treat and per-protocol principles. Results: MBSR was delivered with fidelity and women randomized to MBSR demonstrated a significant increase in mindfulness relative to control. The MBSR intervention did not produce the anticipated stress reducing effects typically associated with mindfulness-based interventions. No differential changes in biomarker expression were observed between groups during the trial. Significant improvements in pain severity (intention-to-treat analysis) and pain-related interference (perprotocol analysis) were observed among women randomized to MBSR relative to control. Change in pain-related interference, but not pain severity, was found to be partially mediated by concomitant change in total mindfulness scores among women randomized to MBSR. Conclusions: Mindfulness interventions have gained significant traction in the treatment of chronic pain conditions. Despite this increase in popularity, our understanding of the association between mindfulness and pain is still evolving. Null findings can be used to help inform our understanding of adjuvant interventions in complex clinical patient populations, and identify what works for who, when and why. Mindfulness-based interventions are not homogenous, nor are they a panacea for disease and illness.