D-dimer-albumin ratio (DAR) as a new biomarker for predicting preoperative deep vein thrombosis after geriatric hip fracture patients

PURPOSE: Hip fractures in the elderly are complicated by preoperative deep vein thrombosis (DVT). The objective of this study is to determine the usefulness of blood-based biomarkers, particularly the D-dimer-albumin ratio (DAR), in predicting preoperative DVT. METHODS: A retrospective observational study was carried out on 1149 patients from a single hospital, and subsequently validated on an additional 626 patients from a separate hospital. The aim was to evaluate the prognostic and predictive value of 10 biomarkers, with a specific emphasis on DAR, in both cohorts. The primary measure of interest was the occurrence of preoperative DVT. RESULTS: The ratio of D-dimer to albumin demonstrated superior predictive capability for preoperative DVT in older patients with hip fractures compared to other biomarkers (AUC = 0.677). Using the optimal cutoff point of 0.24, high DAR was significantly associated with preoperative DVT (OR 3.45, 95% CI 2.00–5.95). Notably, all the DAR definitions detailed above were successfully validated in an external, independent cohort. CONCLUSIONS: DAR may be a valuable biomarker for predicting preoperative DVT in elderly patients with hip fractures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13018-023-04139-z.