OC 42.2 - Deep Vein Thrombosis and Pulmonary Embolism Rates in Total Hip and Total Knee Arthroplasty Patients-A Claims Database Study

Background: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are common post-surgical complications after hip and knee arthroplasty. Venous thromboembolism (VTE) prophylaxis is used to reduce postoperative thrombosis but is associated with bleeding and strategies for different patient populations need to be optimized.

Aims: We investigated postoperative thrombosis and bleeding complications in a contemporary cohort, comparing effectiveness and bleeding by prophylactic agent and underlying risk factors.

Methods: All hip and knee arthroplasty patients from the 2017-2019 IBM MarketScan database who had continuous insurance enrollment three months prior to and following arthroplasty were included. We collected data on demographics, comorbidities, and thromboprophylactic medication. Ninety-day cumulative incidence of postoperative VTE and bleeding were primary outcomes. Univariate analysis was performed to identify risk factors for DVT/PE. A multivariable analysis compared risk of DVT/PE and bleeding, by thromboprophylaxis agent used, adjusted for comorbidities. Patients on multiple prescription anticoagulants and those on chronic anticoagulation were excluded from the multivariable analysis.

Results: A total of 132,625 patients were included in this study. The average age was 61 years, 56.5% were female; 39.5% were hip arthroplasty and 60.5% knee. The 90-day cumulative incidence of VTE was 2.84% (95% CI 2.75-2.93), and 90-day surgical bleeding and all bleeding was 0.73% (95% CI 0.68-0.78) and 4.61% (95% CI 4.49-4.73), respectively. In the univariate analysis, those with a history of DVT/PE or hereditary hypercoagulable diagnosis had a highest VTE risk while outpatient surgery, younger age, and short length of stay had a low risk (Figure 1). Multivariable analysis adjusted for risk factors demonstrated a favorable VTE and safety profile for aspirin overall (Figure 2).

Conclusion(s): DVT/PE rates are driven more by the underlying risk factors than by thromboprophylaxis agent. Aspirin was associated with low DVT/PE and bleeding risk in lower risk populations, but should not be considered in high-risk patients.