Associations between self-reported post-diagnosis physical activity changes, body weight changes, and psychosocial well-being in breast cancer survivors.

PURPOSE: Decreased physical activity and weight gain post-breast cancer diagnosis are associated with negative psychosocial, health, and disease outcomes, but little is known about how these factors interact. The purpose of the present study was to conduct a preliminary examination of the association between post-diagnosis physical activity changes, weight changes, and psychosocial well-being in breast cancer survivors.
METHODS: We examined the association between retrospectively collected, self-reported post-diagnosis changes in physical activity and body weight and post-diagnosis fatigue, anxiety, depression, stress, self-esteem, and health-related quality of life (HRQOL) in breast cancer survivors (N = 1,348) using univariate analyses of covariance with Bonferroni's adjustment.
RESULTS: After adjusting for covariates, maintaining and/or increasing physical activity post-diagnosis was significantly (p < 0.05 for all), independently associated with lower fatigue, anxiety, depression and stress and higher physical self-worth, physical, social, emotional, functional and breast cancer specific well-being and overall HRQOL (effect sizes = 0.23 to 0.60). Maintaining and/or losing weight was significantly (p < 0.05), independently associated with lower fatigue and higher physical self-worth, physical and breast cancer-specific well-being, and overall HRQOL (effect sizes = .28 to 0.87). There were no significant interaction effects between physical activity and body weight changes.
CONCLUSIONS: This study provides preliminary data to suggest that maintaining or increasing physical activity and controlling weight post-diagnosis may be independently, positively associated with psychosocial well-being and HRQOL in breast cancer survivors. In addition, weight management effects may be larger and more outcome-specific while physical activity effects may be more general. Future research is warranted to replicate and confirm these findings.