Risk Factor Analysis And Predicting Nomogram Construction And Validation Of The Morbidity Of Common Bile Duct Stones In Cholecystolithiasis Patients With Elevated Serum Bilirubin

Objective:To analyze the risk factors associated with the morbidity of common bile duct(CBD)stones in patients with cholecystolithiasis with elevated serum total bilirubin and therefore construct a nomogram to predict the corresponding morbidity risks.The nomogram is further validated and the morbidigy risks are quantified,which provides new insights into the diagnosis of CBD stones in cholecystolithiasis patients with elevated serum bilirubin.Methods:Clinical data of 478 patients diagnosed of cholecystolithiasis by abdominal ultrasound together with elevated total bilirubin were retrospectively collected from June 2017 to December 2018,including demographic factors,clinicopathological factors,imaging factors,etc.The admitted patients were randomly divided into a training and a validating group with a ratio of 2:1.In the training group,patients were divided into two groups according to morbidity of CBD stones diagnosed by magnetic resonance cholangiopancreatography.Univariate analysis was used to screen the potential morbidity risk factors of CBD stones,and multivariate logistic regression analysis was used to screen independent risk factors.A nomogram model for predicting the risk of CBD stones in patients with cholecystolithiasis with elevated bilirubin levels was constructed on the basis of independent risk factors.The discrimination,calibration and clinical decision-making ability of the nomogram were verified internally and externally both in the training group and the validating group.Result:Four independent risk factors were obtained based on multivariate analysis,including gallstone diameter < 5mm(p=0.036),CBD diameter > 8mm(p=0.002),evelated direct bilirubin(p=0.029),the ratio of direct bilirubin to total bilirubin>0.35(p=0.001).Based on the above factors,a nomogram model for predicting CBD stones in cholecystolithiasis patients with elevated bilirubin was established.Discrimination analyses showed that the area under curve(AUC)were 0.798 and 0.7809 in thetraining group and verification group.Calibration analysis using Hosmer-Lemeshow tests showed that p values were 0.945 and 0.839.Clinical decision analysis showed good clinical application value.Conclusion:This study screened out the morbidity risk factors of CBD stones in cholecystolithiasis patients with elevated bilirubin.A nomogram model predicting the morbidity risk was constructed.Both internal and external verification showed good prediction performance,which provided new idea for the diagnosis of these patients.