Correlates of objectively measured sedentary behavior in breast cancer survivors

Background: Emerging evidence indicates increased sedentary behavior is associated with poorer health outcomes and quality of life among cancer survivors. However, very little is known about which factors are associated with increased sedentary behavior. The purpose of the present study was to examine potential correlates of sedentary behavior among breast cancer survivors. Methods: We used hierarchical general linear modeling to examine the associations between demographic, disease-specific, and psychosocial factors at baseline and accelerometer-estimated daily proportion of time spent sedentary at 6 months in breast cancer survivors [n = 342; M_age = 56.7 (SD = 9.4)]. All models adjusted for objectively measured moderate and vigorous intensity physical activity and sedentary behavior at baseline. Results: The final model including all baseline potential predictor variables and physical activity and sedentary behavior explained 49.8 % of the variance in the proportion of daily time spent sedentary at 6 months. The following factors were significantly (p < 0.05) associated with increased sedentary behavior among breast cancer survivors: higher number of comorbidities, more advanced disease stage, and increased fatigue severity. Additionally, being treated with surgery and chemotherapy was significantly related to a lower proportion of time spent sedentary compared to women who had received surgery alone. Conclusions: This study provides preliminary insight into factors associated with sedentary behavior in breast cancer survivors. Future research is warranted to understand the potential demographic, disease-specific, psychosocial correlates of sedentary behavior to determine which correlates are potential mechanisms of behavior change and intervention targets.