Optimal duration of anticoagulant thromboprophylaxis in total hip arthroplasty: new evidence in 55,540 patients with osteoarthritis from the Nordic Arthroplasty Register Association (NARA) group

Abstract

Background and purpose — The recommended optimal duration of the thromboprophylaxis treatment in total hip arthroplasty (THA) patients has been a matter of debate for years. We examined the association between short (1–5 days), standard (6–14 days), and extended (≥ 15 days) duration of thromboprophylaxis, with regards to the risk of venous thromboembolism (VTE), major bleeding, and death in unselected THA patients. Patients and methods — We performed a cohort study using prospectively collected data from the population-based hip arthroplasty registries, prescription databases, and patient administrative registries in Denmark and Norway. We included 55,540 primary THA patients with osteoarthritis Results — The 90-day cumulative incidence of VTE was 1.0% for patients with standard treatment (reference), 1.1% for those with short-term treatment (adjusted hazard ratio [aHR] of 1.1, 95% confidence interval (CI) 0.8–1.5) and 1.0% for those with extended treatment (aHR of 0.9, CI 0.8–1.2). The aHRs for major bleeding were 1.1 (CI 0.8–1.6) for short and 0.8 (CI 0.6–1.1) for extended vs. standard treatment. In addition, patients with short and extended treatment had aHRs for death of 1.2 (CI 0.8–1.8) and 0.8 (CI 0.5–1.1) vs. standard treatment, respectively. Patients who started short treatment postoperatively had an aHR for death of 1.8 (CI 1.1–3.1) and absolute risk difference of 0.2%, whereas patients who started short treatment preoperatively had an aHR for death of 0.5 (CI 0.2–1.2) and absolute risk difference of 0.3% compared with patients who had standard treatment with post- and preoperative start, respectively. Interpretation — In routine clinical practice, we observed no overall clinically relevant difference in the risks of VTE and major bleeding within 90 days of THA with respect to thromboprophylaxis duration. However, our data indicate that short-term thromboprophylaxis started postoperatively is associated with increased 90-day mortality. The significance of these data should be explored further.

Similar early mortality risk after cemented compared with cementless total hip arthroplasty for primary osteoarthritis: data from 188,606 surgeries in the Nordic Arthroplasty Register Association database

“… 2013 , Pedersen et al. 2019 ). If use of thromboprophylaxis is related to fixation method we would be confronted with residual confounding in our study.…”

Preventing VTE following total hip and knee arthroplasty: Is prediction the future?

“…8 In spite of all these implemented guidelines on thromboprophylaxis therapy following THA and TKA, about 1.5% of patients still develop symptomatic VTE, which may be explained by several factors. 9,10 First, thromboprophylaxis is not 100% effective, for example, the effectiveness of LMWH on VTE prevention following THA and TKA is estimated to be approximately 50%. 7 Thus, some patients still develop VTE despite pharmacological thromboprophylactic strategies.…”

“…In the current situation (strategy 1), 1.5% of patients develop postoperative VTE despite the use of thromboprophylaxis therapy, assuming drug effectiveness of 50%. Consequently, assuming a baseline major bleeding risk of 0.15% and relative risk for major bleeding from thromboprophylaxis of 5.0, 0.75% of patients develop postoperative major bleeding, 9,10 leading to a total of 22.5/1000 complications (15 VTEs + 7.5 bleedings). To further lower VTE rates, the only option is to intensify thromboprophylaxis (strategy 2).…”

High risk of venous thromboembolism after orthopedic surgery in patients with thrombophilia

“…Simply increasing the intensity of thromboprophylaxis (ie, a higher dosage or longer duration) is not advised because this comes with an increased risk of major bleeding. The estimated risk of major bleeding following total hip and knee arthroplasty is approximately 0.75% 10,11 . Therefore, it would be clinically relevant to know which patients have an increased risk of VTE so that thromboprophylaxis can be tailored to individual patient characteristics.…”

“…The estimated risk of major bleeding following total hip and knee arthroplasty is approximately 0.75%. 10,11 Therefore, it would be clinically relevant to know which patients have an increased risk of VTE so that thromboprophylaxis can be tailored to individual patient characteristics.…”