Abstract
Many women experience distress during diagnosis and treatment of breast cancer, and research suggests that satisfaction with access to social resources both decreases psychological distress and improves duration of survival after breast cancer diagnosis. However, biobehavioral mechanisms linking interpersonal processes to mental and physical health are poorly understood. Studies are also needed to elucidate whether psychosocial interventions that improve social well-being and psychological health affect biological outcomes known to promote cancer disease progression (e.g., inflammation). This study examined a subsample of 78 women enrolled in a 10-week randomized controlled trial of cognitive behavioral stress management (CBSM) at the University of Miami for women diagnosed with early-stage (0 – III) breast cancer. Data for this dissertation were collected at baseline, 2 – 19 weeks after breast cancer surgery (T1), and 6 months later, post-intervention (T2). Aim 1 was to determine whether baseline social well-being related to negative affect, pro-inflammatory and pro-metastatic leukocyte gene expression, and pro-inflammatory serum cytokines. Aim 2 tested whether negative affect mediated the association between social well-being and disease promoting factors. Aim 3 was longitudinal and examined whether CBSM (versus an active control condition) improved social well-being and decreased negative affect and pro-inflammatory and pro-metastatic leukocyte gene expression. Conditional mediation analyses were planned to determine whether CBSM effects on negative affect were mediated by increased social well-being (Aim 4), and whether CBSM effects on leukocyte gene expression were mediated by negative affect (Aim 5). The Social/Family Well-Being subscale of the FACT-B assessed social well-being and the Negative Affect subscale of the Affects Balance Scale measured negative affect. Microarray analysis was used to quantify leukocyte gene expression for specific pro-inflammatory (cytokines, chemokines, and COX-2) and pro-metastatic genes, and ELISA was used to quantify serum concentrations of pro-inflammatory cytokines. Multiple regression analyses using SPSS Statistical Software and controlling for age, stage of disease, days since surgery, and education, with and without body mass index (BMI), were conducted. Results showed that higher levels of social well-being cross-sectionally related to lower levels of negative affect and markers of inflammation and disease-promoting processes at baseline. However, findings did not support the hypotheses that the CBSM intervention would improve social well-being and reduce negative affect and leukocyte gene expression over the 6-month observation period in this sample of women. Meditational hypotheses were not supported. It is possible that the small sample size and short follow-up period limited ability to detect effects. Results have implications for our understanding of the mechanisms linking social resources to biological processes that may relate to health outcomes, and for the development of psychosocial interventions to improve social adaptation to breast cancer.