Development and Prospective Validation of a Novel Risk Score for Predicting the Risk of Lower Extremity Deep Vein Thrombosis Among Trauma Patients

Abstract Background: Trauma patients have an increased risk of deep vein thrombosis (DVT). Early identification of patients with a high risk of DVT after trauma is crucial for thromboembolism prophylaxis. We aimed to develop and prospectively validate a novel risk score based on a nomogram to predict lower extremity DVT among trauma patients.Methods: Clinical data were collected from 281 trauma patients who were admitted to our trauma center within 24 h of admission from September 2016 to January 2019 to develop a novel DVT risk score. The DVT risk estimates were then calculated prospectively based on the score in a new study cohort from February 2019 to July 2020. The technique of least absolute shrinkage and selection operator (LASSO) was used to select variables for the early prediction of DVT in trauma patients. The DVT risk assessment score (DRAS) was constructed by incorporating related features based on the LASSO analysis and nomogram prediction model. Further, the trauma patients were divided into various risk groups according to the DRAS. The incidence of lower extremity DVT was compared between groups and the discrimination of the DRAS was assessed using the area under the curve (AUC). Results: Based on the LASSO method, eight variables (age, injury severity score, body mass index, D-dimer level, fibrin degradation products, prothrombin time, prealbumin level, and hemoglobin level) were included in the DRAS. A total of 166 trauma patients were enrolled in this prospective study. Increased risk of DVT after trauma was related to higher DRAS. The area under the receiver operating characteristic (ROC) curve for the DRAS was 0.890(0.840–0.939) in the validation cohort. Moreover, the discriminatory capacity of the DRAS was superior to that of each variable independently and the Modified Wells score (P<0.05). Conclusions: We developed and prospectively validated the DRAS to predict the risk of lower extremity DVT among trauma patients, which may facilitate early identification of high-risk patients.