Abstract
PURPOSE: The purpose of this study was to identify risk factors for poor health-related quality of life (HRQL) in multi-morbid adult cancer survivors and explore whether perceived treatment and self-management burden mediate any of these relationships. METHODS: Ninety-one multi-morbid cancer survivors (median age: 65 years) completed surveys at baseline and 6 months. Demographic, psychosocial, and health care-related factors were assessed as were perceived treatment burden and general HRQL (physical and mental health). Data on medical diagnoses and cancer treatment were extracted from the medical record. Bivariate correlations screened for associations between predictors and outcomes, with significant predictors entered into multivariable linear regressions to identify unique risk factors for greater treatment burden and poorer HRQL. Follow-up regressions examined whether treatment burden mediated any of the risk factor-outcome relationships. RESULTS: Factors that correlated with higher baseline treatment burden included: having more diagnoses, less formal education, having seen more physicians in the past 6 months, having a mental health diagnosis, not having a set routine for one's self-management, low health literacy, low self-efficacy for self-management, and low social support (Ps <0.05). Among these, factors that also correlated with worse 6-month HRQL outcome included: having more diagnoses, having seen more physicians in the past 6 months, having a mental health diagnosis, not having a set routine for one's self-management, low health literacy, low self-efficacy, and low social support (Ps <0.05). Multivariable regressions showed that some of these factors independently predicted higher treatment burden and/or worse HRQL. Low self-efficacy was the most robust independent risk factor for poor HRQL (bs: 0.34-0.49, Ps <0.005), with evidence supporting that the relationships were partially mediated by treatment burden. CONCLUSION: Monitoring of psychosocial and health care-related risk factors for high treatment burden and poor HRQL can identify multi-morbid cancer survivors in need of extra support and could inform a more personalized treatment approach.