Abstract
Many breast cancer survivors have to deal with a variety of psychological and physiological sequelae including impaired immune responses. The primary purpose of this randomized controlled trial was to determine the efficacy of a mindfulness-based stress reduction (MBSR) intervention for mood disorders in women with breast cancer. Secondary outcomes were symptom experience, health status, coping capacity, mindfulness, posttraumatic growth, and immune status. This RTC assigned 166 women with breast cancer to one of three groups: MBSR (8 weekly group sessions of MBSR), active controls (self-instructing MBSR) and non-MBSR. The primary outcome measure was the Hospital Anxiety and Depression Scale. Secondary outcome measures were: Memorial Symptom Assessment Scale, SF-36, Sense of Coherence, Five Facets of Mindfulness Questionnaire, and Posttraumatic Growth Index. Blood samples were analyzed using flow cytometry for NK-cell activity (FANKIA) and lymphocyte phenotyping; concentrations of cytokines were determined in sera using commercial high sensitivity IL-6 and IL-8 ELISA (enzyme-linked immunosorbent assay) kits. Results provide evidence for beneficial effects of MBSR on psychological and biological responses. Women in the MBSR group experienced significant improvements in depression scores, with a mean pre-MBSR HAD-score of 4.3 and post-MBSR score of 3.3 (P = 0.001), and compared to non-MBSR (P = 0.015). Significant improvements on scores for distress, symptom burden, and mental health were also observed. Furthermore, MBSR facilitated coping capacity as well as mindfulness and posttraumatic growth. Significant benefits in immune response within the MBSR group and between groups were observed. MBSR have potential for alleviating depression, symptom experience, and for enhancing coping capacity, mindfulness and posttraumatic growth, which may improve breast cancer survivorship. MBSR also led to beneficial effect on immune function; the clinical implications of this finding merit further research.