Risk factors analysis and the development and validation of a clinical prediction model for acute mesenteric ischemia-induced intestinal infarction

Abstract

Objective: To investigate the risk factors of intestinal infarction caused by acute mesenteric ischemia (AMI), and develop and validate a clinical prediction model of Nomogram plot for intestinal infarction caused by AMI. Methods: From January 2014 to December 2020, 201 patients with AMI in the Affiliated Hospital of Yunnan University were selected as the modeling group, and 105 patients with AMI in the First Affiliated Hospital of Kunming Medical University were collected as the validation group. The age of patients in the modeling group was (62±12) years, and there were 70 males and 131 females. The age of patients in the validation group was (62±10) years old, and there were 69 males and 36 females. The clinical data including clinical manifestations, laboratory indicators and imaging indicators of patients in the two groups were retrospectively analyzed, and univariate and multivariate binary logistic regression analyses were performed to screen out risk factors for the progression of AMI to intestinal infarction. A Nomogram plot clinical prediction model for AMI causing intestinal infarction was developed using R software, and the differentiation, calibration and net clinical benefit of this Nomogram plot were evaluated by C-index, calibration curve and clinical decision analysis curve. Results: Shock (OR=13.69, 95%CI: 2.31-88.87), body temperature ≥38.0 ℃ (OR=6.39, 95%CI: 1.85-22.11), white blood cells (WBC) ≥18×109/L (OR=1.19, 95%CI: 1.03-1.37), intestinal changes on CT (OR=0.17, 95%CI: 0.04-0.66), peritoneal irritation (OR=0.06, 95%CI: 0.01-0.26), and pH≤7.34 (OR=0.00, 95%CI: 0.00-0.01) were risk factors for intestinal infarction caused by AMI. Body temperature ≥38.0 ℃ (sensitivity: 81.5%, specificity: 87.0%), WBC ≥18×109/L (sensitivity: 84.0%, specificity: 83.0%) and pH ≤7.34 (sensitivity: 70.4%, specificity: 76.7%) were cut-off values for progression to intestinal infarction in patients with AMI. The Nomogram plot prediction model of intestinal infarction induced by AMI was established by using the above parameters and validated internally and externally. The C index of validation group and modeling group were 0.96 (95%CI: 0.921-0.999) and 0.98 (95%CI: 0.962-0.996), respectively. The calibration curves of the validation group and the modeling group were shaped near the reference line, and the deviation from the reference line was low. The clinical decision analysis curves of validation group and modeling group showed that the clinical prediction model of Nomogram could bring better clinical net benefit for AMI patients. Conclusions: Shock, temperature, white blood cells, intestinal changes on CT, peritoneal irritation sign, and PH are independent risk factors for AMI-induced intestinal infarction. The Nomogram plot established by these factors can effectively predict the probability of AMI patients progressing to intestinal infarction.