Posted 06.24.2016 | by AMRA
Every year nearly 250,000 American women are diagnosed with breast cancer. Diagnosis and treatment can be frightening and arduous, and the interval following active treatment is often fraught with anxiety and uncertainty. Prior studies show that breast cancer survivors can benefit from psychological interventions, but little is known about which interventions yield the best outcomes.
Carlson et al. [Psycho-Oncology] conducted a randomized, controlled trial comparing two evidence-supported programs, Mindfulness-Based Cancer Recovery (MBCR) and supportive expressive group therapy (SET), in reducing stress and improving the quality of life of distressed breast cancer survivors.
The researchers randomly assigned 271 distressed Canadian breast cancer survivors (average age = 55 years) to either MBCR or SET. MBCR is an 8-week group mindfulness-based intervention modeled after Mindfulness Based Stress Reduction. SET is a 12-week group treatment developed at Stanford University that aims to mobilize social support, facilitate emotional openness and expressiveness, and strengthen coping skills.
All participating survivors had been diagnosed with Stage I-III breast cancer, completed surgical, chemotherapy, and/or radiation treatment, and scored ≥ 4 on a 10-point distress scale. Participants completed self-report measures of mood, stress, quality-of-life, perceived social support, spiritual well-being and post-traumatic growth before treatment, immediately after treatment, and at 6 month and 12 month follow-up.
Dropout rates during treatment were relatively high (MBCR=32%, SET=28%), with additional attrition (MBCR=28%, SET=23%) prior to post-treatment and follow-up assessments. The results included data from all the participants who enrolled in the trial.
Both groups improved on all of the mood subscales, but the improvement was significantly greater for MBCR participants, especially on measures of fatigue, anxiety, and confusion (average Cohen’s d = 0.37). Both groups also significantly improved on most of the stress subscales, but the MBCR group improved more (average d = 0.29).
MBCR participants also showed greater improvements on quality-of-life subscales (average d = 0.21), social support subscales (average d = 0.20), spiritual well-being subscales (average d = .23) and post-traumatic growth subscales (average d = 0.19).
These improvements and the overall patterns of MBCR superiority were largely maintained on follow-up with some exceptions: there were slight increases in depression and decreases in affectionate support for both groups, a lessening in the size of group differences in some somatic complaints, and a loss of significance for some quality-of-life measures.
The difference between groups for posttraumatic growth continued to widen on follow-up, with MBCR participants continuing to improve at a greater rate.
Among breast cancer survivors, MBCR performed better than SET on a broad variety of psychosocial measures, both initially and at one-year follow-up. The study is limited by its high attrition rates and the large number of multiple comparison tests performed.
Carlson, L. E., Tamagawa, R., Stephen, J., Drysdale, E., Zhong, L., & Speca, M. (2016). Randomized-controlled trial of mindfulness-based cancer recovery versus supportive expressive group therapy among distressed breast cancer survivors (MINDSET): Long-term follow-up results. Psycho-Oncology.