Depression and Anxiety Mediate the Associations between Nutritional Status, Functional Capacity, and Quality of Life in Patients with Cancer

Cancer patients are at risk of malnutrition, which influences their functional status, mental health (MH), and quality of life (QoL). This study aimed to examine the associations between nutritional status, functional capacity, and aspects of QoL in cancer patients, as well as the potential mediating role of depression and anxiety in these associations. Patients with various types of cancer (n = 152) were recruited from the Attikon University Hospital, Greece. Validated questionnaires were used to assess nutritional status (PG-SGA), QoL (SF-36 and EQ-5D-3L), functional capacity (ECOG), depression, and anxiety (HADS and BEDS). Handgrip strength (HGS) was also measured. Poor nutritional status was inversely associated with functional capacity, QoL, depression, and anxiety, after adjusting for confounding factors (all P & LE; 0.05). Mediation analysis indicated a significant indirect effect of nutritional status on various parameters of functional capacity and QoL through depression and anxiety, after adjusting for age and sex. Mediated proportion ranged from 26.3-34% to 23.1-82.8% for functional capacity and QoL, respectively. A significant proportion of the effect of nutritional status on QoL and functional capacity can be partly attributed to psychological effects, highlighting the significance of integrating all aforementioned aspects in the nutritional intervention for cancer patients.