Prevalence of Nutritional Risk and Obesity in Mexican Cancer Outpatients

<b>Introduction:</b> Malnutrition is a critical issue among cancer patients, leading to adverse clinical outcomes, including increased treatment toxicity, reduced physical function, and decreased survival. Nutritional screening is essential to identify patients at risk and provide timely interventions. <b>Objectives:</b> This study aimed to assess the effectiveness of various nutritional screening tools in identifying the risk of malnutrition and obesity in Mexican cancer outpatients. <b>Methods:</b> A cross-sectional study was conducted with 396 adult cancer outpatients at a public hospital in Mexico. Nutritional risk was evaluated using NRS-2002, MUST, MST, NUTRISCORE, and PG-SGA, while malnutrition was assessed using GLIM criteria and PG-SGA. Anthropometric and demographic data were collected. Sensitivity, specificity, and kappa coefficients were calculated to determine the performance of the screening tools. <b>Results:</b> Nutritional risk was identified in 22.7-26.5% of patients, with the highest agreement observed between MUST and PG-SGA (k = 0.64). Malnutrition prevalence was higher using GLIM criteria (37.4%) compared to PG-SGA (25.8%, <i>p</i> < 0.001). Overweight and obesity affected 37.1% and 23.5% of patients, respectively. Low BMI and reduced HGS were strongly associated with nutritional risk and malnutrition (<i>p</i> < 0.001). <b>Conclusions:</b> MUST and PG-SGA are reliable tools for nutritional screening in cancer outpatients, while GLIM criteria detect a higher prevalence of malnutrition than PG-SGA. The high rates of overweight and obesity highlight the complex nutritional challenges in this population, emphasizing the need for tailored nutritional assessments and interventions.