[Analysis of Risk Factors and Construction of Predictive Model for Iliac Vein Compression Syndrome Combined with Deep Vein Thrombosis of the Lower Extremities].

OBJECTIVE

To explore the risk factors of lower extremity deep vein thrombosis (DVT) in patients with iliac vein compression syndrome (IVCS) and to construct a risk prediction model.

METHODS

A total of 187 patients with IVCS admitted to The First Hospital of Lanzhou University from January 2023 to December 2024 were selected as the research subjects. Clinical data such as gender, age, underlying diseases, surgical history, anticoagulation history, body mass index (BMI), and laboratory test results of all patients were collected. According to whether the patients were combined with lower extremity DVT, they were divided into the DVT group (90 cases) and the non-DVT group (97 cases). Univariate and multivariate Logistic regression analyses were used to analyze the risk factors of lower extremity DVT in patients with IVCS. One hundred patients with IVCS admitted to our hospital from January 2025 to July 2025 were selected as the validation group for model validation. The Hosmer-Lemeshow test was used to evaluate the goodness-of-fit of the model, and the predictive performance of the model was evaluated based on the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

There were statistically significant differences between the DVT group and the non-DVT group in terms of age, BMI, lower extremity mobility disorder, postoperative infection, previous history of thrombosis, D-dimer levels, anticoagulation history, bed rest time, uric acid levels, prothrombin time, and fibrinogen levels (P < 0.05). Multivariate Logistic regression analysis revealed advanced age (OR =1.107, 95%CI : 1.033-1.187, P =0.004), plasma D-dimer >0.5 mg/L (OR =12.799, 95%CI : 1.124-145.782, P =0.040), BMI >25 kg/m2 (OR =5.695, 95%CI : 1.474-22.008, P =0.012), previous history of thrombosis (OR =40.453, 95%CI : 7.234-226.214, P < 0.001), no history of anticoagulation (OR =8.020, 95%CI : 2.274-28.279, P =0.001), bed rest time >72 hours (OR =38.500, 95%CI : 2.696-549.888, P =0.007), hyperuricemia (OR =1.026, 95%CI : 1.016-1.035, P < 0.001) and hyperfibrinogen (OR =3.786, 95%CI : 1.366-10.491, P =0.010) were independent risk factor for lower extremity DVT in patients with IVCS. The Hosmer-Lemeshow test showed that, χ2 =9.608, the P value was 0.294, the goodness-of-fit of the model was good. ROC curve analysis showed that the AUC of the model was 0.946 (95%CI : 0.914-0.978), the specificity was 0.918, and the sensitivity was 0.833. The prediction accuracy of this model was 90.00%, and the Kappa consistency coefficient was 0.780.

CONCLUSION

Advanced age, elevated D-dimer, BMI >25 kg/m2, previous history of thrombosis, no anticoagulation prevention, bed rest time >72 hours, hyperuricemia and hyperfibrinogen are all independent risk factors for lower extremity DVT in patients with IVCS. In clinical work, these factors should be emphasized and active intervention measures should be taken to prevent the occurrence of lower extremity DVT, and improve the prognosis of diseases.