Safety of direct oral anticoagulants in solid organ transplant recipients: A meta-analysis

Use of Direct Anticoagulants in Kidney Transplant Recipients: Review of the Current Evidence and Emerging Perspectives

Thromboembolic events and atrial fibrillation are common among kidney transplant recipients (KTRs), and these conditions typically require anticoagulation. Traditionally, vitamin K antagonists were used for management, but the use of direct oral anticoagulants (DOACs) has increased in KTRs. In the general population, DOACs are recommended over warfarin, but the applicability of these recommendations to KTRs is unclear because of risk-benefit concerns. There is some hesitancy to use DOACs in KTRs because of their dependence on renal clearance for elimination, potential drug-drug interactions, and limited data. To date, studies of DOACs in KTRs have demonstrated that they are efficient in thromboembolic events, major bleeding is rare, and drug-drug interactions appear rare. However, no guidance yet exists about the use of DOACs, reversal of DOAC action, and the pre- and post-kidney transplant management of DOACs in KTRs, and the evidence base is scarce. Thus, decisions on DOAC use in KTRs are based on expert opinion and the resources and experiences of individual transplant centers. This review summarizes 10 published studies on the use of DOACs in 741 KTRs, evaluating the side effects, efficacy, drug-drug interactions, and perioperative management compared with those of 1320 KTRs using vitamin K antagonists. Although current data are limited, DOACs appear to be relatively safe and effective in KTRs, with some studies suggesting lower bleeding rates and better kidney function than with vitamin K antagonists. However, more research with larger patient groups is needed to draw definitive conclusions.

Management of heart disease in renal transplant recipients: a national Delphi survey-based SET/SEC/SEN consensus document

Renal transplantation improves the survival and quality of life of patients with end-stage renal disease. Cardiovascular disease is the leading cause of morbidity and mortality in renal transplant recipients. The bidirectional relationship between renal and heart disease creates a unique clinical scenario that demands a comprehensive and personalized approach. This expert consensus, drafted by the Spanish Society of Transplantation, the Spanish Society of Cardiology, and the Spanish Society of Nephrology, aims to assess current practices and propose strategies for the management of heart disease in renal transplant recipients. A panel of Spanish nephrologists and cardiologists with expertise in renal and heart transplantation reviewed the scientific evidence concerning the current management of heart disease in renal transplant recipients. Subsequently, consensus statements were created through a 2-round Delphi methodology, resulting in 30 statements covering key topics such as the identification of renal transplant candidates, the management of heart disease in renal transplant recipients, and eligibility for combined heart-kidney transplantation in patients with both end-stage renal disease and cardiac disease. These consensus statements provide expert guidance for the management of heart disease in renal transplant recipients, an area where published clinical evidence remains limited.

Direct Oral Anticoagulants in Patients With ESRD and Kidney Transplantation

Direct oral anticoagulant (DOAC) use has significantly increased because major medical organizations endorse their role for conditions in which anticoagulation is indicated. Owing to important pharmacokinetic properties, the use of apixaban and rivaroxaban requires careful consideration in at-risk populations such as those with kidney disease. Both apixaban and rivaroxaban undergo some degree of renal elimination, and thus total drug exposure is increased in patients with renal insufficiency and/or those undergoing renal replacement therapy (RRT). The available clinical trial and real-world data in this population suggests that apixaban is likely at least comparably effective as warfarin at preventing thromboembolic events and is likely safer when evaluating bleeding risk. Rivaroxaban data is more limited, and the reported results are more discordant. Both apixaban and rivaroxaban have been used successfully in patients with end-stage renal disease (ESRD) undergoing kidney transplant listing as well as in the posttransplant setting. Prospective clinical trials evaluating the safety and efficacy of apixaban and rivaroxaban in various conditions where anticoagulation is indicated should include patients with ESRD and kidney transplant recipients to help further define the role that these important novel agents should play in these complex patient populations.

Safety and efficacy of direct oral anticoagulants in kidney transplant recipients: A systematic review and meta-analysis

INTRODUCTION

Direct-acting oral anticoagulants (DOACs) have recently shown potential efficacy for many conditions without the need for regular monitoring. However, their use in kidney transplant recipients (KTRs) is controversial, with no clear consensus on how they compare to vitamin K antagonists (VKAs), which have traditionally been used as preferred anticoagulation therapy in these patients.

METHODS

PubMed, Cochrane Central, and Embase databases were systematically searched up to December 2023 for studies comparing DOACs versus VKAs in KTRs. The main outcomes of interest included venous thromboembolism (VTE), major bleeding, graft failure, mortality, and changes in estimated glomerular filtration rate (eGFR). Statistical analyses were performed using RStudio 4.1.2 software.

PROSPERO ID

CRD42024498423.

RESULTS

Five studies with a total of 959 participants were included. Of these, 433 (45.15 %) participants were treated with DOACs. The mean age of participants was 60.05 years, and 65.9 % were male. The use of DOACs in KTRs was associated with a significant reduction in major bleeding (RR 0.56; 95 % CI 0.35 to 0.90; p = 0.02; I2 = 0 %) and mortality (RR 0.49; 95 % CI 0.33 to 0.74; p = 0.0006; I2 = 0 %). No significant differences were found between groups in VTE (RR 0.82; 95 % CI 0.47 to 1.43; p = 0.48; I2 = 12 %), graft failure (RR 0.43; 95 % CI 0.14 to 1.27; p = 0.13; I2 = 52 %), and eGFR (MD 3.72 mL/Kg/1.73 m2; 95 % CI -1.58 to 9.03; p = 0.17; I2 = 0 %). Evidence quality for some outcomes remains low to moderate, limiting the confidence in these conclusions.

CONCLUSION

Our meta-analysis suggests that DOACs represent an effective anticoagulation strategy in KTR, with a significant reduction in major bleeding and mortality relative to VKA.

A Novel Preoperative Classification System for Selecting Suitable Surgeries in Liver Transplant Patients with Portal Vein Cavernous Transformation

BACKGROUND

To evaluate the new preoperative Changgung classification (CC) system of portal vein thrombosis (PVT) in choosing suitable operative procedures to reconstruct portal veins during liver transplantation (LT) in patients with portal vein cavernous transformation (PVCT).

METHODS

This retrospective observational study analyzed data from allograft LTs performed for various liver diseases.

RESULTS

The study included 22 males and 4 females with LT indications comprising cirrhosis (n = 9), hepatocellular carcinoma (n = 12), PVCT (n = 2), liver failure from fulminant hepatitis B (n = 1), dysfunction of transplanted liver (n = 1), and chronic rejection of transplanted liver (n = 1). Patients were classified according to Yerdel (21 Yerdel II and 5 Yerdel III) and CC (C1-C5). In total 16 simple operations were performed on C1-C3 cases and 9 complex operations on C4-C5 cases, with one additional simple operation. The distribution according to the Yerdel classification was 16 simple and 5 complex operations in Yerdel II cases and 1 simple and 4 complex operations in Yerdel III cases. The median follow-up time was 27.5 months with overall one-year and three-year OS rates of 88.1% and 83.9% for the cohort. Specifically, the one-year OS rates for patients classified as C1-3 vs. C4-5 were 93.3% and 80.0%, while the three-year OS rates were 86.7% and 80.0%, respectively (p = 0.526).

CONCLUSION

The CC proposed in this study shows comparable potential to the Yerdel classification in preoperatively identifying the need for complex surgical techniques in LT patients with PVCT and may also have predictive power for the survival benefits following LT.

Recent Advances across the Spectrum of Heart Failure and Heart Transplant

In recent years, remarkable progress has been accomplished in the heart failure (HF) landscape, with novel drugs and groundbreaking device approaches [...].

Immunosuppressive therapy and oral anticoagulation in kidney transplant recipients: Direct oral anticoagulants versus vitamin-k antagonists

BACKGROUND

direct oral anticoagulants (DOACs) are an alternative to conventional antagonist of vitamin-K (AVK). However, immune suppressive drugs (ISDs) may interfere with DOACs pharmacokinetic.

AIM OF THIS STUDY

evaluate safety and efficacy profile of DOACs compared to AVK in kidney transplant recipients (KTRs) treated with ISDs.

METHODS

a multi-center study from 4 Italian University hospitals enrolling consecutive KTRs on DOACs or AVK was carried out. Sixty-six patients on DOACs were compared with fifty patients on AVK with similar clinical features. Serial evaluation of renal function and serum levels of ISDs during 18 months follow-up (FU) was performed.

RESULTS

Mean age of DOACs patients was 67±9 and mean eGFR was 58,3± 30,4mL/min/1.73m2. ISDs included tacrolimus (n=47, 71%), cyclosporin (n=13, 20%), everolimus (n=10, 7%) and sirolimus (n=4, 6%). After 14 days of DOACs therapy initiation there was a slight increase of serum levels of tacrolimus (+0.19±0.67 p=0.80) and cyclosporine (+0.12±0.25 p=0.94) not statistically significant. Levels of Tacrolimus and cyclosporin were stable at serial evaluation during 18-months follow-up. There were no thromboembolic events among patients treated with DOACs or AVK and no differences in term of major bleeding (6% vs 4% p=0.69), at long-term follow-up. There was no difference in term of eGFR decline from start therapy to 18 months FU between DOACs vs AVK therapy (-3.9±1 vs -3.8±2 p=0.82).

CONCLUSION

DOACs have similar safety and efficacy than AVK among KTRs treated with ISDs. However, careful evaluation of potential drug interaction and ISDs serum levels is needed.

Oral Anticoagulants after Heart Transplantation-Comparison between Vitamin K Antagonists and Direct Oral Anticoagulants

AIMS

Patients after heart transplantation (HTX) often require oral anticoagulants (OACs) due to atrial arrhythmias or thromboembolic events but little is known about the post-transplant use of direct oral anticoagulants (DOACs). We investigated the frequency, indications, and complications of DOACs and vitamin K antagonists (VKAs) after HTX.

METHODS

We screened all adult patients for the use of post-transplant OACs who underwent HTX at Heidelberg Heart Center between 2000 and 2021. Patients were stratified by type of OAC (DOAC or VKA) and by DOAC agents (apixaban, dabigatran, edoxaban, or rivaroxaban). Indications for OACs comprised atrial fibrillation, atrial flutter, pulmonary embolism, upper and lower extremity deep vein thrombosis, as well as intracardiac thrombus.

RESULTS

A total of 115 of 459 HTX recipients (25.1%) required OACs, including 60 patients with DOACs (52.2%) and 55 patients with VKAs (47.8%). Concerning DOACs, 28 patients were treated with rivaroxaban (46.7%), 27 patients with apixaban (45.0%), and 5 patients with edoxaban (8.3%). We found no significant differences between both groups concerning demographics, immunosuppressive drugs, concomitant medications, indications for OACs, ischemic stroke, thromboembolic events, or OAC-related death. Patients with DOACs after HTX had a significantly lower one-year rate of overall bleeding complications (p = 0.002) and a significantly lower one-year rate of gastrointestinal hemorrhage (p = 0.011) compared to patients with VKAs after HTX in the Kaplan-Meier estimator.

CONCLUSIONS

DOACs were comparable to VKAs concerning the risk of ischemic stroke, thromboembolic events, or OAC-related death but were associated with significantly fewer bleeding complications in HTX recipients.

Safety and mortality outcomes for direct oral anticoagulants in renal transplant recipients

PURPOSE

Direct oral anticoagulants (DOACs) are increasingly used in renal transplant recipients (RTR), but relatively understudied in this population. We assess the safety of post-transplant anticoagulation with DOACs compared to warfarin.

METHODS

We conducted a retrospective study of RTRs at the Mayo Clinic sites (2011-present) that were anticoagulated for greater than 3 months excluding the 1st month post-transplant. The main safety outcomes were bleeding and all-cause mortality. Concomitant antiplatelet and interacting drugs were noted. DOAC dose adjustment was assessed according to common US prescribing practices, guidelines, and/or FDA labeling.

RESULTS

The median follow-up was longer for RTRs on warfarin (1098 days [IQR 521, 1517]) than DOACs (449 days [IQR 338, 942]). Largely, there were no differences in baseline characteristics and comorbidities between RTRs on DOACs (n = 208; apixaban 91.3%, rivaroxaban 8.7%) versus warfarin (n = 320). There was no difference in post-transplant use of antiplatelets, immunosuppressants, most antifungals assessed, or amiodarone. There was no significant difference in incident major bleeding (8.4 vs. 5.3%, p = 0.89), GI bleeding (4.4% vs. 1.9%, p = 0.98), or intra-cranial hemorrhage (1.9% vs. 1.4%, p = 0.85) between warfarin and DOAC. There was no significant difference in mortality in the warfarin group compared to DOACs when adjusted for follow-up time (22.2% vs. 10.1%, p = 0.21). Rates of post-transplant venous thromboembolism, atrial fibrillation or stroke were similar between the two groups. 32% (n = 67) of patients on DOACs were dose reduced, where 51% of those reductions were warranted. 7% of patients that were not dose reduced should have been.

CONCLUSIONS

DOACs did not have inferior bleeding or mortality outcomes compared to warfarin in RTRs. There was greater use of warfarin compared to DOACs and a high rate of improper DOAC dose reduction.

A Review of Direct-acting Oral Anticoagulants and Their Use in Solid Organ Transplantation

Direct-acting oral anticoagulant (DOAC) use has increased dramatically since their introduction because of the growing evidence of proven efficacy and enhanced safety compared with warfarin and the low-molecular-weight heparins in the general population. Unfortunately, there is a dearth of quality data regarding the safety and efficacy of the DOACs in patients awaiting organ transplant and those who received a solid organ transplant. This review aims to evaluate the available literature and considerations regarding anticoagulation use in transplant recipients, focusing on preoperative, perioperative, and postoperative DOAC use.