Age-adjusted D-Dimer Thresholds Combined with the Modified Wells Score as a Predictor of Lower Extremity Deep Venous Thrombosis

Background Neurosurgical patients are at an increased risk of deep venous thrombosis (DVT), which, if not properly managed, can lead to pulmonary embolism. This study aimed to investigate the accuracy of age-adjusted D-dimer thresholds combined with the modified Wells score as a predictor for lower extremity DVT diagnosis. Methods We conducted a study among patients aged >50 years with suspected lower extremity DVT in the neurosurgery intensive care unit between December 2019 and December 2020. Receiver operating characteristic curve analysis was performed to examine the diagnostic capacity of age-adjusted D-dimer combined with the modified Wells score. Results A total of 233 participants, with an average age of 71.81 ± 12.59 years, were enrolled in the study. The mean D-dimer levels were 0.73 ± 0.39 mg/L. Among the participants, 57 (57.9%, 33 males) were diagnosed with DVT. The age-adjusted D-dimer combined with the modified Wells score had the highest area under the curve for diagnosing lower extremity DVT compared to D-dimer and age-adjusted D-dimer alone, with an AUC of 0.858. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the age-adjusted D-dimer combined with the modified Wells score for DVT diagnosis were 78.95%, 80.68%, 57%, 92.2%, and 80.26%, respectively. When analyzing subgroups, the accuracy was 79.55% for participants with cerebral hemorrhage, 81.69% for those with craniocerebral injury, 74.99% for participants with intracranial infection, and 88.89% for those with craniocerebral tumor. Conclusion The combination of the age-adjusted D-dimer thresholds with the modified Wells score might effectively predict lower extremity DVT.