The Type of Preoperative Oral Antithrombotics as a Risk Factor for Venous Thromboembolism After Hip Surgery: A Retrospective Study

TL;DR

This study found that the type of preoperative oral antithrombotics affects the risk of blood clots after hip surgery, with clopidogrel reducing and cilostazol increasing the risk.

Contribution

The study identifies specific antithrombotic drugs as risk factors for postoperative venous thromboembolism in hip surgery patients.

Findings

Clopidogrel was associated with a lower risk of postoperative VTE compared to other antithrombotics.

Cilostazol was linked to a higher risk of postoperative VTE.

Low preoperative albumin levels increased the risk of VTE after hip surgery.

Abstract

Background and Objectives: Hip surgery is increasingly performed among elderly patients. Oral antithrombotics, which are taken for patients’ underlying diseases, are a main concern regarding perioperative bleeding. Postoperative venous thromboembolism (VTE) is a leading cause of mortality after hip surgery. Therefore, administration of preoperative oral antithrombotics is a double-edged sword in hip surgery. In this study, we examined the correlation between the occurrence of postoperative VTE and the type of oral antithrombotics administered preoperatively. Materials and Methods: We analyzed the medical records of 601 patients aged 19 and over who underwent hip surgery from January 2021 to June 2023. The patients were assigned to two groups as follows: Groups VTE+ (patients who developed postoperative VTE) and VTE- (patients who did not develop postoperative VTE), respectively. Results: Of the 139 patients who had been taking oral antithrombotics for 6 months or more, 24 were allocated to group VTE+ and 115 to group VTE-, respectively. The number of patients who took clopidogrel and cilostazol was significantly higher in groups VTE- and VTE+, respectively (12.5 vs. 33.9%, p = 0.038, odds ratio (OR) = 0.278, 95% confidence interval (CI) = 0.078–0.991; 20.8 vs. 5.2%, p = 0.010, 95% CI = 1.325–17.245; group VTE+ vs. group VTE-). Preoperative albumin levels were significantly lower in group VTE+ (3.4 ± 0.6 g/dL vs. 3.7 ± 0.4 g/dL, p = 0.004, OR = 0.285, 95% CI = 0.115–0.702). In multivariate regression analysis, the results were statistically significant for clopidogrel, cilostazol, and preoperative albumin levels (p = 0.035, OR = 0.237, 95% CI = 0.062–0.901; p = 0.011, OR = 6.479, 95% CI = 1.542–27.226; p = 0.002, OR = 0.211, 95% CI = 0.080–0.558). Conclusions: Among the patients who had been taking oral antithrombotics for ≥6 months, clopidogrel had a prophylactic effect, but cilostazol showed an aggravating effect on postoperative VTE in hip surgery. Preoperative hypoalbuminemia increases the risk of postoperative VTE in hip surgery.

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