The role of controlling nutritional status score in predicting postthrombotic syndrome in patients with lower extremity deep venous thrombosis

This study aimed to explore the efficacy of Prognostic Nutritional Index (PNI), Controlling Nutritional Status (CONUT), and Nutritional Risk Index (NRI) in predicting postthrombotic syndrome (PTS) in patients with lower extremity deep vein thrombosis (DVT) based on peripheral blood samples. We reviewed and analyzed patients with lower extremity DVT in our hospital from June 2020 to December 2023. The receiver operating characteristic (ROC) curve identified the best nutritional scoring system for a logistic regression model. Restricted cubic spline (RCS) analysis examined the nonlinear link between the CONUT score and PTS risk, using knots at the 10th, 50th, and 90th percentiles of the CONUT score.The study investigated 246 cases of lower extremity DVT, PTS occurred in 59 patients (23.2%). Multifactorial analysis indicated that body mass index (BMI), prior varicose veins, recurrent venous thromboembolism (VTE), and CONUT score were independent risk factors for patients with DVT developing PTS (P < 0.05). In the multivariate analysis model, a CONUT score of > 4.5 was independently associated with PTS (P < 0.001). RCS analysis demonstrated a significant nonlinear relationship (P for nonlinearity = 0.028), with the risk of PTS increasing with CONUT scores up to an inflection point of 7, after which the risk plateaued. Our study suggest that an independent correlation was found between CONUT score and PTS in patients with lower extremity DVT.