The aim of this study was to develop a predictive model of nutritional risk in elderly CAPI patients through retrospective cross-sectional data, to identify core predictors applicable to community/nursing home settings, and to validate the predictive augmentation of the combined Braden Score and Nutritional Blood Indicator in hospitalised patients, to provide a basis for stratified nutritional risk management. A retrospective study was conducted to include 424 elderly CAPI patients. They were divided into two groups according to NRS2002 score. Demographic parameters, physiological function parameters and blood parameters were collected. All above indicators of the patients with CAPI were analysed to explore their correlation with nutritional risk. Among 424 participants, 294 patients (69.34%) were at nutritional risk. Independent risk factors identified were aged ≥ 70 years, reduced intake in the last week, and decrease in BMI, Braden score, ALB (albumin), and PA (prealbumin) levels. The AUCs of the first four parameters mentioned above and all the above parameters were 0.816 and 0.872, respectively. The value of aged ≥ 70 years, reduced intake in the past week, BMI, and Braden score in combination to predict and assess nutritional risk is high, which can be used to predict nutritional risk for elderly patients with CAPI who are at home or in nursing homes. The combination of the above parameters combined with albumin and prealbumin has an even higher predictive value in elderly patients hospitalised with CAPI.