Financial well-being as a mediator of the relationship between multimorbidity and health-related quality of life in people with cancer

Background: It is unknown whether financial well-being mediates the impact of multimorbidity on the health-related quality of life (HRQoL) of cancer patients. Methods: Participants were recruited from three outpatient oncology clinics of Hong Kong public hospitals. Multimorbidity was assessed using the Charlson Comorbidity Index. Financial well-being, the mediator of the association between multimorbidity and HRQoL outcomes, was assessed using the Comprehensive Score for Financial Toxicity Functional Assessment of Chronic Illness Therapy. The HRQoL outcomes were assessed using the Functional Assessment of Cancer Therapy-General (FACT-G) and its four sub-dimensions. Mediation analyses were conducted using SPSS PROCESS v4.1. Results: Six-hundred and forty cancer patients participated in the study. Multimorbidity had a direct effect on FACT-G scores independent of financial well-being (beta for path c' = -0.752, p < 0.001). In addition, multimorbidity had an indirect effect on FACT-G scores through its effect on financial well-being (beta for path a = -0.517, p < 0.05; beta for path b = 0.785, p < 0.001). Even after adjustments were made for the covariates, the indirect effect of multimorbidity on FACT-G via financial well-being remained significant, accounting for 38.0% of the overall effect, indicating partial mediation. Although there were no statistically significant associations between multimorbidity, social well-being, and emotional well-being, the indirect effects of multimorbidity on physical and functional well-being through financial well-being remained significant. Conclusions: Poor financial well-being attributable to multimorbidity partially mediates the direct impact of chronic conditions on HRQoL in Chinese cancer patients, particularly their physical and functional well-being.