Objective:To construct a risk prediction model for malnutrition in lung cancer patients undergoing chemotherapy and develop an online calculator to predict individual risk values.Methods:A convenience sampling method was used to select 386 lung cancer patients admitted to the Department of Medical Oncology at the Cancer Hospital of the Chinese Academy of Medical Sciences in Beijing from October 2022 to March 2023 as research subjects. They were divided into a well-nourished group and a malnourished group based on the presence or absence of malnutrition. Multivariate Logistic regression analysis was used to identify the influencing factors of malnutrition in lung cancer patients undergoing chemotherapy. The nomogram of the risk prediction model was drawn and the online calculator was developed using R Studio 4.3.2 software. The model was evaluated using the area under the receiver operating characteristic curve, sensitivity, specificity, Hosmer-Lemeshow goodness-of-fit test, and decision curve analysis.Results:Among the 372 lung cancer patients undergoing chemotherapy, there were 237 males and 135 females, with 147 in the well-nourished group and 225 in the malnourished group. The incidence rate of malnutrition was 60.48%. Age 60 - 70 years [ OR(95% CI) = 1.74(1.03 - 2.93)], body mass index > 24.0 kg/m 2 [ OR(95% CI) = 0.58(0.36 - 0.93)], regular exercise [ OR(95% CI) = 0.53(0.33 - 0.85)], physical frailty [pre-frailty: OR(95% CI) = 2.74(1.61 - 4.65); frailty syndrome: OR(95% CI) = 2.67(1.37 - 5.22)], insomnia [ OR(95% CI) = 2.81(1.59 - 4.94)], and sarcopenia [ OR(95% CI) = 4.09(1.32 - 12.70)] were identified as independent influencing factors for malnutrition in lung cancer patients undergoing chemotherapy (all P<0.05). The area under the curve of the constructed prediction model was 0.76, with a sensitivity of 72%, specificity of 72%, a Hosmer-Lemeshow goodness-of-fit test P value of 0.594, and a mean absolute error of 0.018. Conclusions:The risk prediction model and online calculator for malnutrition in lung cancer patients undergoing chemotherapy constructed in this study demonstrated good performance, providing a reference for precise nutritional intervention and early screening in clinical practice.

Objective:To construct a risk prediction model for malnutrition in lung cancer patients undergoing chemotherapy and develop an online calculator to predict individual risk values.Methods:A convenience sampling method was used to select 386 lung cancer patients admitted to the Department of Medical Oncology at the Cancer Hospital of the Chinese Academy of Medical Sciences in Beijing from October 2022 to March 2023 as research subjects. They were divided into a well-nourished group and a malnourished group based on the presence or absence of malnutrition. Multivariate Logistic regression analysis was used to identify the influencing factors of malnutrition in lung cancer patients undergoing chemotherapy. The nomogram of the risk prediction model was drawn and the online calculator was developed using R Studio 4.3.2 software. The model was evaluated using the area under the receiver operating characteristic curve, sensitivity, specificity, Hosmer-Lemeshow goodness-of-fit test, and decision curve analysis.Results:Among the 372 lung cancer patients undergoing chemotherapy, there were 237 males and 135 females, with 147 in the well-nourished group and 225 in the malnourished group. The incidence rate of malnutrition was 60.48%. Age 60 - 70 years [ OR(95% CI) = 1.74(1.03 - 2.93)], body mass index > 24.0 kg/m 2 [ OR(95% CI) = 0.58(0.36 - 0.93)], regular exercise [ OR(95% CI) = 0.53(0.33 - 0.85)], physical frailty [pre-frailty: OR(95% CI) = 2.74(1.61 - 4.65); frailty syndrome: OR(95% CI) = 2.67(1.37 - 5.22)], insomnia [ OR(95% CI) = 2.81(1.59 - 4.94)], and sarcopenia [ OR(95% CI) = 4.09(1.32 - 12.70)] were identified as independent influencing factors for malnutrition in lung cancer patients undergoing chemotherapy (all P<0.05). The area under the curve of the constructed prediction model was 0.76, with a sensitivity of 72%, specificity of 72%, a Hosmer-Lemeshow goodness-of-fit test P value of 0.594, and a mean absolute error of 0.018. Conclusions:The risk prediction model and online calculator for malnutrition in lung cancer patients undergoing chemotherapy constructed in this study demonstrated good performance, providing a reference for precise nutritional intervention and early screening in clinical practice.