Weight-Based Aspirin Dosing May Further Reduce the Incidence of Venous Thromboembolism Following Primary Total Joint Arthroplasty

Update on antithrombotic therapy and body mass: a clinical consensus statement of the European Society of Cardiology Working Group on Cardiovascular Pharmacotherapy and the European Society of Cardiology Working Group on Thrombosis

Obesity and underweight are a growing health problem worldwide and a challenge for clinicians concerning antithrombotic therapy, due to the associated risks of thrombosis and/or bleeding. This clinical consensus statement updates a previous one published in 2018, by reviewing the most recent evidence on antithrombotic drugs based on body size categories according to the World Health Organization classification. The document focuses mostly on individuals at the extremes of body weight, i.e. underweight and moderate-to-morbid obesity, who require antithrombotic drugs, according to current guidelines, for the treatment or prevention of cardiovascular diseases or venous thromboembolism. Managing antithrombotic therapy or thromboprophylaxis in these individuals is challenging, due to profound changes in body composition, metabolism and organ function, and altered drug pharmacokinetics and pharmacodynamics, as well as weak or no evidence from clinical trials. The document also includes artificial intelligence simulations derived from in silico pharmacokinetic/pharmacodynamic models, which can mimic the pharmacokinetic changes and help identify optimal regimens of antithrombotic drugs for severely underweight or severely obese individuals. Further, bariatric surgery in morbidly obese subjects is frequently performed worldwide. Bariatric surgery causes specific and additional changes in metabolism and gastrointestinal anatomy, depending on the type of the procedure, which can also impact the pharmacokinetics of antithrombotic drugs and their management. Based on existing literature, the document provides consensus statements on optimizing antithrombotic drug management for underweight and all classes of obese patients, while highlighting the current gaps in knowledge in these complex clinical settings, which require personalized medicine and precision pharmacology.

Efficacy and safety of aspirin in venous thromboembolism prevention after total hip arthroplasty, total knee arthroplasty or fracture

Background: This study aims to analyse the efficacy and safety of aspirin in the prevention of venous thromboembolism (VTE) for patients undergoing total hip arthroplasty (THA), total knee arthroplasty (TKA) or fracture. Patients and methods: Two independent investigators searched PubMed, Embase, Cochrane and ClinicalTrials.gov from January 2000 to June 2023 to retrieve randomized control trials (RCTs) about aspirin in VTE prevention after arthroplasty or fracture. Then, the relative risk (RR) was utilized to evaluate its efficiency and safety. Results: A total of 16 RCTs with 27,864 patients were included. There was no statistical difference in the incidence of deep-vein thrombosis (RR: 1.31, p = 0.100), pulmonary embolism (RR:1.05, p = 0.850), VTE (RR:1.28, p = 0.290), major bleeding (RR:0.96, p = 0.900), and death (RR:1.01, p = 0.960) between the aspirin group and the anticoagulants group. Subgroup analysis showed that a relatively higher incidence of deep-vein thrombosis in patients undergoing TKA (RR:1.49, p = 0.030), fracture (RR:1.48, p = 0.001), patients receiving 81 mg aspirin twice daily (RR:1.48, p = 0.001) and patients from North America (RR:1.57, p<0.001) when comparing aspirin with anticoagulants. Meanwhile, the incidence of VTE was higher in patients receiving 100 mg aspirin once daily (RR:1.82, p<0.001) compared with anticoagulants. Additionally, the incidence of all bleeding (RR:2.00, p = 0.030) was higher in patients receiving aspirin in Asia compared with anticoagulants. Conclusions: In terms of clinical effectiveness and safety, aspirin (antiplatelet agent) was generally not inferior to anticoagulants in the prevention of VTE after THA, TKA, or fracture. Notably, the clinical effectiveness of aspirin was affected by different surgical types, the doses of aspirin and races.

Prior COVID-19 and Venous Thromboembolism Risk in Total Joint Arthroplasty in Patients Over 65 Years of Age

BACKGROUND

The COVID-19 pandemic has been associated with increased risks of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE). However, there is limited literature investigating prothrombotic states and complications after total hip arthroplasty (THA) and total knee arthroplasty (TKA). We investigated (1) trends in VTE, PE, and DVT rates post-THA and TKA from 2016 to 2019 compared to 2020 to 2021 and (2) associations between prior COVID-19 diagnosis and VTE, PE, and DVT.

METHODS

A national dataset was queried for elective THA and TKA cases from 2016 to 2021. We first assessed trends in 90-day VTE prevalence between 2016 to 2019 and 2020 to 2021. Second, we investigated associations between previous COVID-19 and 90-day VTE with regression models.

RESULTS

From 2016 to 2021, a total of 2,422,051 cases had an annual decreasing VTE prevalence from 2.2 to 1.9% (THA) and 2.5 to 2.2% (TKA). This was evident for both PE and DVT (all trend tests P < .001). After adjusting for covariates (including vaccination status), prior COVID-19 was associated with significantly increased odds of developing VTE in TKA patients (odds ratio 1.2, 95% confidence interval 1.1 to 1.4, P = .007), but not DVT or PE (P > .05). There were no significant associations between prior COVID-19 and VTE, DVT, or PE after THA (P > .05).

CONCLUSIONS

Our study suggests that a previous diagnosis of COVID-19 is associated with increased odds of VTE, but not DVT or PE, in TKA patients. Ongoing data monitoring is needed given our effect estimates, emerging COVID-19 variants, and evolving vaccination rates.

Aspirin is a safe and effective thromboembolic prophylaxis after total knee arthroplasty: a systematic review and meta-analysis

PURPOSE

Patients undergoing total knee arthroplasty (TKA) are at high risk for thromboembolic events compared to non-surgical patients. Both anticoagulants and antiplatelet agents are used as antithrombotic prophylaxis in TKA. The aim of this review is to understand the role of aspirin in the prevention of thromboembolic events and to compare its efficacy and safety with the main anticoagulants used in antithromboembolic prophylaxis in TKA.

METHODS

A systematic review and meta-analysis was performed according to the PRISMA guidelines. An electronic systematic search was conducted using PubMed, Scopus, and the Cochrane Central Registry to evaluate studies that compared aspirin with other anticoagulants, in terms of deep venous thrombosis and pulmonary embolism after TKA. The meta-analysis compared the rate of complications between aspirin and other anticoagulants.

RESULTS

Thirteen studies were included in the systematic review for a total of 163,983 patients, and 10 studies were included in the meta-analysis. The meta-analysis demonstrated no statistically significant differences between aspirin and other anticoagulants in terms of the rate of deep venous thrombosis (OR 0.93, 95% CI 0.81-1.08, p = 0.35) and pulmonary embolism (OR 0.89, 95% CI 0.56-1.41, p = 0.61).

CONCLUSION

Aspirin is safe, effective, and not inferior to other main anticoagulants in preventing thromboembolic events following TKA.

Obesity and the Risk of Venous Thromboembolism after Major Lower Limb Orthopaedic Surgery: A Literature Review

The risk of venous thromboembolism following total joint arthroplasty is significantly greater than those of other types of elective orthopaedic procedures. This risk is increased in obesity due to the associated prothrombotic physiological and hematological changes that predispose to embolic events. The prevalence of obesity is increasing in the aging population, which contributes to a further increase in the risk of postoperative thrombosis in the older patients. There is a lack of clear evidence regarding dosing information for thromboprophylaxis medications in patients with obesity. As a result, the currently available thromboprophylaxis guidelines do not provide specific recommendations for this group. Suboptimal dosing regimens for these medications can place these patients at a risk of bleeding or clotting complications postsurgery. Hence any increase in dosage may require intensive surveillance for the residual anticoagulant effects and careful balancing of risks and benefits on an individual basis. Our review discusses the basis for increased thrombotic risk in obesity, the evidence supporting dosage recommendations, and the implications of the current guidelines for pharmacological thromboprophylaxis in patients with obesity undergoing lower limb arthroplasty.

Bleeding and thrombosis outcomes in hospitalised COVID-19 patients on low-molecular-weight heparin and antiplatelet therapy

Background. An increased incidence of thromboembolic events in hospitalised COVID‐19 patients has been demonstrated despite the use of low‐molecular‐weight heparin (LMWH). Antiplatelet therapy prior to admission and early in the disease course has been hypothesised to be protective against thrombosis.Objectives. To describe the bleeding and thrombosis outcomes in hospitalised patients with confirmed COVID‐19 receiving LMWH, with and without concomitant antiplatelet therapy. Secondary objectives were to explore predictors of bleeding and thrombosis outcomes, and dosing practices of antiplatelet therapy and LMWH. Methods. We conducted a descriptive, cross‐sectional study of bleeding and thrombosis outcomes at Tygerberg Academic Hospital, Cape Town, South Africa, during the first COVID‐19 wave, in 808 hospitalised patients with confirmed COVID‐19 receiving LMWH with and without concomitant antiplatelet therapy. Multivariate logistic regression analysis was performed if predictors were deemed statistically and clinically significant. Results. Patients receiving both LMWH and antiplatelet therapy had similar bleeding outcomes compared with patients only receiving LMWH (odds ratio (OR) 1.5; 95% confidence interval (CI) 0.6 ‐ 4.0). Patients receiving both LMWH and antiplatelet therapy had increased odds of developing thrombosis compared with patients only receiving LMWH (OR 4.8; 95% CI 2.1 ‐ 10.7).Conclusion. The bleeding risk in COVID‐19 patients receiving both LMWH and antiplatelet therapy was not significantly increased. A potentially higher risk of thrombosis in patients receiving LMWH and antiplatelet therapy was observed. However, this could reflect confounding by indication. Randomised studies are required to further evaluate the use of antiplatelet therapy to treat hospitalised patients with COVID‐19.

Effect of body weight on bleeding events of aspirin in ischemic stroke or transient ischemic attack patients

WHAT IS KNOWN AND OBJECTIVES

Bleeding is the most common adverse reaction to aspirin and can lead to drug discontinuation or even be life-threatening in the secondary prevention of stroke or transient ischemic attack. The aim of this study was to evaluate risk factors for bleeding adverse reaction of aspirin in ischemic stroke or transient ischemic attack.

METHODS

This retrospective analysis included patients treated with aspirin (100 mg) as a secondary prevention for ischemic stroke or transient ischemic attack. The bleeding events that occurred during the first year were collected, including gastrointestinal, skin, nasal cavity, gum, and urinary tract bleeding events. Then, univariate and multivariate logistic regression analyses were used to identify independent factors associated with bleeding events of aspirin.

RESULTS AND DISCUSSION

A total of 578 patients were enrolled in this study, and 58 patients developed bleeding during the first year of secondary prevention. Body weight and combination with selective serotonin reuptake inhibitors were found to be significant risk factors for overall bleeding (p = 0.025 and 0.012). Body weight below 60 kg was a risk factor for overall bleeding and gastrointestinal bleeding events.

WHAT IS NEW AND CONCLUSION

Patients weighing less than 60 kg were at increased risk of bleeding with 100 mg aspirin for secondary prevention of cerebral infarction transient ischemic attack.