Effects of treatment factors, comorbidities and health-related quality of life on self-efficacy for physical activity in cancer survivors

Objective: The physical and psychological benefits of exercise for cancer survivors are well documented. Researchers have examined self-efficacy (SE) as a target for promoting exercise; however, the predictors of SE, including treatment factors and comorbidities, have not been examined extensively. The purpose of this cross-sectional analysis was to examine how variables related to cancer and cancer treatment, comorbid health problems, health-related quality of life (QOL), and depression relate to SE for physical activity in cancer survivors. Methods: This secondary analysis examined treatment factors, comorbidity, and QOL data from 148 breast cancer and 134 prostate cancer survivors who had participated in studies examining exercise and QOL. A predictive regression model was developed by testing each variable individually with SE and including the variables that had a significance of ≤0.2 in a multivariate regression model. Results: For the breast cancer population, vitality (B = 0.23, p = 0.02), bodily pain (B = 0.16, p = 0.07), and mental health (B = 0.15, p = 0.01) were associated with SE for physical activity. For the prostate cancer survivors, education, (B = -0.20, p = 0.036) vitality (B = 0.26, p = 0.01), and bodily pain (B = 0.13, p = 0.182) remained in the model. Conclusion: Treatment factors and comorbidities were not associated with SE for physical activity, but health-related QOL factors of vitality and bodily pain were associated with SE. Thus, subjective measures of well-being are important factors to consider when developing targeted interventions to increase physical activity in cancer survivors.