【Abstract】Objective To analyze the risk factors for malnutrition in elderly patients with colorectal cancer (CRC) during chemotherapy, and construct a prediction model for malnutrition in the patients. Methods A retrospective study was conducted on 354 elderly CRC patients admitted in our hospital from January 2022 to February 2023. They were divided into training set and verification set in a ratio of 2∶1. In the training set, univariate and multivariate logistic regression analyses were used to screen the risk factors of malnutrition in the patients during chemotherapy, and a prediction model was then constructed. In the verification set, receiver operating characteristic (ROC) curve was drawn to verify the prediction performance of the model. Data analysis was performed by using SPSS 22.0 software, and Chi-square test and independent sample t test were applied for intergroup comparison in enumeration and measurement data, respectively. Results There were 236 cases in the training set and 118 cases in the validation set. No significant differences were observed in general demographic data and clinical baseline data between two groups (P>0.05). In the training set, univariate analysis revealed that age, clinical stage, average monthly family income, mid-arm muscle circumference, BMI, protein intake and total energy intake were related factors for malnutrition in elderly CRC patients during chemotherapy (P<0.05). Multivariate logistic regression analysis showed that age, average monthly family income <5 000 yuan and clinical stage Ⅳ were independent risk factors (P<0.05), and protein intake was a protective factor of malnutrition in these patients (P<0.05). Based on the results of multivariate logistic regression analysis, a prediction model of malnutrition in elderly CRC patients during chemotherapy was constructed. Hosmer-Lemeshow fit test indicated that the model had good calibration (χ2=4.763, P=0.689). In the verification set, the area under the curve, sensitivity and specificity of the model was 0.805,81.61% and 85.48%, respectively. Conclusion The incidence rate of malnutrition is quite high among the elderly CRC patients during chemotherapy, and its influencing factors include age, average monthly family income, clinical stage and protein intake. The prediction model established on this basis has certain reference value to screen high-risk patients with malnutrition.
