Malnutrition in gastrointestinal cancer manifests before systemic therapy and is associated with fatigue and reduced physical quality of life

Background There is a high malnutrition risk in patients with gastrointestinal tumors. Yet, it is unknown when malnutrition manifests and how changes in nutritional status are related to quality of life and fatigue at different stages of oncologic therapy. Patients and Methods In a prospective observational study, we recruited patients with initial diagnosis of any gastrointestinal tumor requiring systemic therapy and respective patients already receiving treatment. Subjects underwent comprehensive nutritional assessment at enrollment and after 3 months. In addition, patients reported data on physical activity (IPAQ-SF), quality of life (SF-12), and fatigue (EORTC QLQ-FA12). Besides baseline associations, relations between changes in nutritional status and patient-reported outcomes during treatment were analyzed. Results We included 66 patients (mean(±SD) age: 62.1(±10.6) yrs.; 68% male), of which 29 had received initial diagnosis and 37 were already undergoing treatment. Baseline clinical characteristics and nutritional status were comparable between groups. With 88% of patients, GLIM-defined malnutrition was highly prevalent at baseline and associated with fatigue, reduced physical activity and quality of life (p < 0.01, respectively). Among 36 study completers, only minor fat mass (p = 0.033) and progressed weight loss (p = 0.025) indicated further nutritional deterioration. Development of cachexia, but not malnutrition or sarcopenia, during treatment was associated with impaired patient-reported outcomes, i.e., higher fatigue (rho = 0.400; p = 0.019) and lowered physical activity (rho=-0.423; p = 0.013). Conclusion Most patients with gastrointestinal cancer are malnourished already at diagnosis. Impaired nutritional status is closely linked with reduced quality of life and fatigue, especially their physical components. Trials are warranted to test whether optimized nutrition support can halt further aggravation during treatment.