MBSR During AI Therapy for Breast Cancer

Overview

This study will use non-invasive neuroimaging (i.e., MRI) to examine whether Mindfulness-Based Stress Reduction (MBSR) improves neural markers of cognitive function for postmenopausal women taking aromatase inhibitor (AI) therapy for breast cancer. The pilot randomized controlled trial will obtain preliminary efficacy of MBSR versus Health Enhancement Program (HEP) active control to improve neural markers of cognitive function. The final sample will include 32 postmenopausal women with breast cancer. MBSR and HEP groups will meet for a matched schedule of 8 weekly 2.5-hour sessions and a one-day weekend retreat. Specimen and data collection will be done at three time points: pre-randomization (i.e., within three weeks before beginning the intervention), within three weeks after completion of the intervention, and approximately three months (+/- three weeks) post intervention. Change scores for neuroimaging parameter estimates will be correlated with change scores for measures of cognitive function and affect. Differential expression of genes will be correlated with neuroimaging parameter estimates.

Adjuvant aromatase inhibitor (AI) therapy improves disease-free and overall survival for postmenopausal women after surgery for hormone receptor-positive breast cancer. Among symptoms associated with AI therapy are changes in cognitive function. Up to 25% of postmenopausal women with breast cancer report that they experience changes in cognitive function during AI therapy. Studies using neuropsychological tests found subtle deteriorations in verbal and visual learning and memory-as well as concentration, working memory, and executive function-for as many as a third of these patients. Changes in cognitive function may be associated with changes in affect (e.g., worry, depressive symptoms). Neural markers of cognitive changes, including changes in brain function and structure, may underlie changes in cognitive function. The investigators' recent preliminary neuroimaging work to describe neural markers of cognitive changes suggests that postmenopausal women with breast cancer have inefficient cognitive-emotion processing before AI therapy, as evidenced by greater neural activity in the hippocampus (working memory) and amygdala (emotion processing) during task performance compared to controls. During AI therapy, patients show differential activation compared to controls in the dorsolateral prefrontal cortex (executive function and working memory), medial prefrontal cortices (cortical control of amygdala responses), and hippocampus. Stress responses could partially explain relationships between AI therapy and neural markers of cognitive changes. The Mindfulness Stress-Buffering Account suggests that interventions such as Mindfulness-Based Stress Reduction (MBSR) may improve stress responses by attenuating negative appraisals of stress and reducing reactivity to stressful situations. For example, mindfulness meditation improved psychological stress responses in women with breast cancer. It improved some measures of cognitive function. Mindfulness practices reduced physiological markers of stress responses, including inflammatory markers in women with breast cancer and in stressed community adults, as well as cortisol reactivity for breast cancer survivors and during chemotherapy for colorectal cancer. Although similar neural deficits as were found in the investigators' preliminary work have been shown to improve in stressed adult populations using MBSR, it is not known whether the intervention improves neural deficits in women taking AI therapy (estrogen, production of which is blocked by AI therapy, is neuroprotective and promotes neural plasticity). Genetic variability was previously found to moderate the effect of MBSR on self-reported cognitive function. Therefore, it is possible that inter-individual variability in the expression of genes involved in stress responses could moderate relationships between AI therapy and neural markers of cognitive changes during MBSR. Taken together, MBSR may improve neural markers of cognitive changes shown in preliminary work to be deficient in postmenopausal women before and during AI therapy for breast cancer by targeting stress responses. Changes in these neural markers may correspond to improved self-report and neuropsychological measures of cognitive function. Hypothesis: Stress reduction, moderated by gene expression, blunts the impact of AI therapy on neural markers of cognitive function, thereby improving cognitive function and affect in women with breast cancer.