Malnutrition is associated with poor health-related quality of life in surgical patients with gastrointestinal cancer

•Malnutrition, assessed by various tools, was associated with poor health-related quality of life in patients with gastrointestinal cancer in the preoperative period.•Subjective global assessment was able to predict a clinically relevant decrease in health-related quality of life.•The prevalence of malnutrition, according to the subjective global assessment and the percentage of weight loss, was close to 70%. The aim of this study was to evaluate the association between preoperative nutritional status and health-related quality of life (HRQoL) in patients with gastrointestinal cancer who were admitted for elective surgical treatment. This was a cross-sectional study in which patients with a diagnosis of gastrointestinal cancer were evaluated before a surgical procedure. The nutritional assessment included subjective global assessment (SGA) and measurements of weight loss percentage, bioelectrical impedance, and functional capacity. HRQoL was evaluated by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire–Core 30 (EORTC QLQ-C30). Statistical analyses were performed with a significance level of 5%. The sample size was calculated based on a pilot study. We evaluated 132 patients, the majority of whom were men. The median age of the patients was 62 y, and the most prevalent tumors were in the colon, rectum, and anus (52.3%). The SGA highlighted the high prevalence of malnutrition (69.9%), which was confirmed by the rates of weight loss (73.8%) and the low fat-free mass index (56.8%). Malnourished patients and patients with severe weight loss had worse functional, symptom, global health and quality of life scores (P < 0.05). Malnutrition, according to the SGA, decreased physical function and role performance scores by 9 and 20 points, respectively (P < 0.05). Malnutrition, assessed by various tools, was associated with poor HRQoL of surgical patients with gastrointestinal cancer.