Functions of Resiliency Traits and Processes in Differential Effects of CBSM on Quality of Life in Breast Cancer Survivors: A Moderated Mediation Model

Background Although there is evidence that cognitive behavioral therapy (CBT)-based group interventions can improve quality of life (QoL) in women undergoing treatment for breast cancer (BC) little is known about factors that mediate and moderate these effects. We examined a) the mediating role of benefit finding on QoL changes after a Cognitive Behavioral Stress Management (CBSM) intervention, and b) whether this mediation effect differed based on baseline optimism in the first year following surgery for BC. Methods We used data from a prior CBSM trial in 240 women with stage 0–3 BC who completed measures of benefit finding (Benefit Finding Scale, BFS), QoL (Functional Assessment of Cancer Treatment, FACT-G), and optimism (Life Orientation Test-Revised) at baseline (2 – 10 weeks post-surgery), 6-months and 12-months after randomization. CBSM-related changes and mediation and moderation effects were assessed using latent growth curve models. Results We found CBSM increased benefit finding (b = 2.65, p < 0.01), emotional (b = 0.53, p < 0.01), and functional QoL (b = 0.71, p < 0.05) over time. CBSM-related changes in emotional QoL were mediated by increased benefit finding (indirect effect = 0.68, 95% bootstrapped CI: 0.17, 1.56) but only among participants with low to moderate optimism at baseline. Conclusion CBSM intervention improved emotional QoL over the first year of breast cancer treatment by increasing benefit finding among women who reported low trait optimism suggesting those who will most likely benefit from improving benefit finding during this stressful period.