Pharmacokinetics, pharmacodynamics, and safety of apixaban in subjects with end-stage renal disease on hemodialysis

Safety and efficacy of apixaban versus vitamin K antagonists in patients undergoing dialysis: a systematic review and meta-analysis

BACKGROUND

This review aims to evaluate the safety and efficacy of apixaban vs. vitamin K antagonists (VKAs) in patients on dialysis.

METHODS

All types of studies published on PubMed, Embase, CENTRAL, and Web of Science up to 10 September 2023 and comparing outcomes of apixaban vs. VKA in dialysis patients were eligible.

RESULTS

Two randomized controlled trials (RCTs) and six retrospective studies were included. Apixaban treatment was associated with significantly lower risk of major bleeding (RR: 0.61; 95% CI: 0.48, 0.77; I2 = 50%) and clinically relevant non-major bleeding (RR: 0.82, 95% CI: 0.68, 0.98, I2 = 9%) compared to VKA. Meta-analysis also showed that the risk of gastrointestinal bleeding (RR: 0.74, 95% CI: 0.64, 0.85, I2 = 16%) and intracranial bleeding (RR: 0.64, 95% CI: 0.49, 0.84, I2 = 0%) was significantly reduced with apixaban. Meta-analysis showed no difference in the risk of ischemic stroke (RR: 0.40, 95% CI: 0.06, 2.69, I2 = 0%), mortality (RR: 1.26, 95% CI: 0.74, 2.16, I2 = 94%) and recurrent venous thromboembolism (RR: 1.02, 95% CI: 0.87, 1.21, I2 = 0%) between the two groups. Subgroup analysis of RCTs showed no difference in bleeding outcomes.

CONCLUSIONS

Low-quality evidence from a mix of RCTs and retrospective studies shows that apixaban may have better safety and equivalent efficacy as compared to VKA in dialysis patients. Apixaban treatment correlated with significantly reduced risk of major bleeding and clinically relevant nonmajor bleeding in observational studies but not in RCTs. The predominance of retrospective data warrants caution in the interpretation of results.

Apixaban Use in Patients with Kidney Impairment: A Review of Pharmacokinetic, Interventional, and Observational Study Data

Chronic kidney disease (CKD) remains a significant global health issue and is a leading cause of mortality worldwide. Patients with CKD have an increased risk of developing atrial fibrillation (AF) and venous thromboembolism (VTE). While direct oral anticoagulants (DOACs) have become a standard of care for anticoagulation (AC) in patients with AF and VTE, the appropriate use of these agents in comorbid kidney impairment warrants detailed discussion. This scientific narrative review summarizes the effectiveness and safety of apixaban use in patients with renal dysfunction by assessing the current published pharmacokinetic, interventional, observational, and guideline data. Apixaban is a highly selective, orally active, direct inhibitor of factor Xa, with well-established pharmacokinetics and consistent clinical outcomes across a broad range of patient populations, including those with kidney impairment. Overall, the scientific literature has shown that apixaban has a favorable clinical efficacy and safety profile compared with vitamin K antagonists for patients with AF or VTE and comorbid kidney impairment. These data support the approved label dosing strategy of apixaban in reducing the risk of stroke/systemic embolism in patients with nonvalvular AF and in treating VTE across all ranges of kidney function. Both clinician experience and knowledge of patient-specific factors may be required in the management of comorbid patients with advanced CKD or those requiring dialysis, as data on these patients are limited.

Reprint of: Efficacy and safety of apixaban compared to warfarin for nonvalvular atrial fibrillation in end-stage renal disease on hemodialysis

BACKGROUND

This study compared the efficacy and safety of apixaban and warfarin in patients with nonvalvular atrial fibrillation (NVAF) and end-stage renal disease (ESRD) on hemodialysis (HD). Apixaban decreased incidence of stroke and bleeding compared with warfarin in major clinical trials that excluded patients with severe renal dysfunction. Apixaban is no longer contraindicated in patients with ESRD on HD with NVAF based on pharmacokinetic studies. Limited clinical data exist for patients with ESRD on HD on apixaban.

METHODS

A retrospective chart review was performed on patients with a diagnosis of NVAF and ESRD on HD who were prescribed apixaban or warfarin for stroke prevention in the years 2018 through 2019. Patients' charts were reviewed for up to a 2-year period. Patients on renal replacement therapy other than HD, those using anticoagulation for reasons other than NVAF, patients with Child-Pugh Class C cirrhosis, and those with severe mitral valve stenosis were excluded. The primary outcome was emergency department visits or hospital admissions for ischemic stroke or transient ischemic attack. Secondary outcomes included major or minor bleeding and adverse effects.

RESULTS

A total of 181 patients were screened; 110 patients met eligibility criteria and were included in the analysis. Four patients (7.5%) in the apixaban group and 6 patients (10.5%) in the warfarin group met the primary outcome of hospitalization or emergency department visit for stroke (P = 0.742). Symptomatic bleeding occurred in 39.6% of patients in the apixaban group and 36.8% in the warfarin group (P = 0.918). A trend in major bleeding occurred more often in the warfarin group, 52.4% versus 49.2% (P = 0.758).

CONCLUSIONS

There were no statistically significant differences in efficacy and safety outcomes between apixaban and warfarin in patients with NVAF and ESRD on HD in the intention-to-treat analysis of our study. Larger trials are needed to further analyze this patient population.

Evaluation of Apixaban Use in Patients With Advanced Kidney Disease

Background: Current guidelines and literature suggest apixaban may be used in patients with severe kidney disease and atrial fibrillation (AF) for stroke and systemic embolism risk reduction (SSE) or patients with acute venous thromboembolism (VTE). Limited data is available for long-term safety and efficacy outcomes in this patient population. Objective: Evaluate the use of apixaban for AF or VTE in patients with advanced kidney disease. Methods: This single-center, retrospective, Investigational Review Board approved study evaluated patients ≥18 years of age with severe kidney disease on apixaban therapy for VTE or AF from March 1, 2018, to December 31, 2020. The primary outcome was major bleeding from apixaban initiation/continuation until 12 months after discharge. The secondary outcomes included a composite bleed (major bleeding, clinically relevant non-major bleeding, and minor bleeding), the occurrence of VTE or SSE, and death during hospitalization from any cause other than bleeding. Results: Overall, 156 patients met inclusion criteria. Six patients experienced major bleeding (3.8%). Composite bleeding occurred in 16 patients (10.3%); no patients had SSE or VTE, and 4 patients died from causes other than bleeding (2.6%). Limitations included the small sample size and retrospective nature of the study. Conclusion: This study demonstrated that patients with advanced chronic kidney disease on apixaban for AF or VTE had low major bleeding and similar overall bleeding rates compared with previously published literature. When considering the use of apixaban in this population, risks and benefits should be weighed in addition to the consideration of FDA-label dosing guidance.

Apixaban Pharmacokinetics and Bioequivalence of Two Tablet Formulations: A Randomized, Open-Label, Crossover Study, Fasting Condition in Healthy Indonesian Volunteers

The present study aimed to assess the bioequivalence of a new apixaban generic with reference formulation. Twenty-six healthy volunteers were recruited for an open-label, balanced, randomized, 2-treatment, 2-sequence, 2-period, single oral dose study. Following overnight fasting, each volunteer received 5 mg of apixaban test and reference formulations as single doses, separated by a 1-week washout period. Twenty blood samples were collected at predose and multiple time points between 0.5 and 72 hours after dosing. A validated ultra-performance liquid chromatography-tandem mass spectrometry detection method following a protein precipitation step was implemented to determine apixaban concentrations. Noncompartmental analysis was used to derive the pharmacokinetic parameters, which were then compared between the test and reference products using a multivariate analysis of variance. The pharmacokinetic parameters of the test product were not statistically different from the reference product, and the 90% confidence intervals of apixaban natural log-transformed area under the concentration-time curve from time 0 to infinity, area under the concentration-time curve from time 0 to the last measurable concentration, and maximum concentration were within 80%-125% based on the bioequivalence acceptance range criteria. The test and reference formulations of apixaban are bioequivalent in healthy subjects under fasting conditions.

Meta-analysis evaluating apixaban in patients with atrial fibrillation and end-stage renal disease requiring dialysis

Background

Warfarin is considered the primary oral anticoagulant for patients with atrial fibrillation and end-stage renal disease (ESRD) requiring dialysis. Although warfarin can offer significant stroke prevention in this population, the accompanying major bleeding risks make warfarin nearly prohibitive. Apixaban was shown to be superior to warfarin in preventing stroke or systemic embolism, with a lower risk of bleeding and mortality in a large, randomized trial of individuals with mostly normal renal function but none with ESRD.

Methods

We systematically reviewed evidence comparing apixaban versus warfarin for atrial fibrillation in this population, and evaluated outcomes of stroke or systemic embolism, and major bleeding using random-effects models. The main safety outcome was major bleeding, and the main effectiveness outcome was stroke or systemic embolism.

Results

We found five observational studies of 10 036 patients (2638 receiving apixaban, and 7398 receiving warfarin) meeting inclusion criteria. Pooled analysis demonstrated a significant reduction in major bleeding with apixaban as compared to warfarin (odds ratio [OR] 0.51, 95% confidence interval [CI] 0.42-0.61; p < .0001). Apixaban was also associated with a reduction in intracranial bleeding (OR 0.58, 95% CI 0.37-0.92; p = .02) and in gastrointestinal bleeding (OR 0.61, 95% CI 0.51-0.73; p < .0001). Furthermore, apixaban was associated with a reduction in stroke/systemic embolism (OR 0.64, 95% CI 0.50-0.82; p < .0001).

Conclusion

Apixaban was associated with superior outcomes and reduced adverse events compared to warfarin in observational studies of patients with atrial fibrillation on dialysis. Randomized controlled studies are needed to confirm these findings.

Anticoagulation for Patients With Concomitant Atrial Fibrillation and End-Stage Renal Disease: A Systematic Review and Network Meta-Analysis

BACKGROUND

Concomitant atrial fibrillation and end-stage renal disease is common and associated with an unfavorable prognosis. Although oral anticoagulants have been well established to prevent thromboembolism, the applicability in patients under long-term dialysis remains debatable. The study aimed to determine the efficacy and safety of anticoagulation in the dialysis-dependent population.

METHODS AND RESULTS

An updated network meta-analysis based on MEDLINE, EMBASE, and the Cochrane Library was performed. Studies published up to December 2022 were included. Direct oral anticoagulants (DOACs, dabigatran, rivaroxaban, apixaban 2.5/5 mg twice daily), vitamin K antagonists (VKAs), and no anticoagulation were compared on safety and efficacy outcomes. The outcomes of interest were major bleeding, thromboembolism, and all-cause death. A total of 42 studies, including 3 randomized controlled trials, with 185 864 subjects were pooled. VKAs were associated with a significantly higher risk of major bleeding than either no anticoagulation (hazard ratio [HR], 1.47; 95% CI, 1.34-1.61) or DOACs (DOACs versus VKAs; HR, 0.74 [95% CI, 0.64-0.84]). For the prevention of thromboembolism, the efficacies of VKAs, DOACs, and no anticoagulation were equivalent. Nevertheless, dabigatran and rivaroxaban were associated with fewer embolic events. There were no differences in all-cause death with the administration of VKAs, DOACs, or no anticoagulation.

CONCLUSIONS

For dialysis-dependent populations, dabigatran and rivaroxaban were associated with better efficacy, while dabigatran and apixaban demonstrated better safety. No anticoagulation was a noninferior alterative, and VKAs were associated with the worst outcomes.

Efficacy and safety of apixaban compared to warfarin for nonvalvular atrial fibrillation in end-stage renal disease on hemodialysis

BACKGROUND

This study compared the efficacy and safety of apixaban and warfarin in patients with nonvalvular atrial fibrillation (NVAF) and end-stage renal disease (ESRD) on hemodialysis (HD). Apixaban decreased incidence of stroke and bleeding compared with warfarin in major clinical trials that excluded patients with severe renal dysfunction. Apixaban is no longer contraindicated in patients with ESRD on HD with NVAF based on pharmacokinetic studies. Limited clinical data exist for patients with ESRD on HD on apixaban.

METHODS

A retrospective chart review was performed on patients with a diagnosis of NVAF and ESRD on HD who were prescribed apixaban or warfarin for stroke prevention in the years 2018 through 2019. Patients' charts were reviewed for up to a 2-year period. Patients on renal replacement therapy other than HD, those using anticoagulation for reasons other than NVAF, patients with Child-Pugh Class C cirrhosis, and those with severe mitral valve stenosis were excluded. The primary outcome was emergency department visits or hospital admissions for ischemic stroke or transient ischemic attack. Secondary outcomes included major or minor bleeding and adverse effects.

RESULTS

A total of 181 patients were screened; 110 patients met eligibility criteria and were included in the analysis. Four patients (7.5%) in the apixaban group and 6 patients (10.5%) in the warfarin group met the primary outcome of hospitalization or emergency department visit for stroke (P = 0.742). Symptomatic bleeding occurred in 39.6% of patients in the apixaban group and 36.8% in the warfarin group (P = 0.918). A trend in major bleeding occurred more often in the warfarin group, 52.4% versus 49.2% (P = 0.758).

CONCLUSIONS

There were no statistically significant differences in efficacy and safety outcomes between apixaban and warfarin in patients with NVAF and ESRD on HD in the intention-to-treat analysis of our study. Larger trials are needed to further analyze this patient population.

Physiologically based pharmacokinetic modeling of apixaban to predict exposure in populations with hepatic and renal impairment and elderly populations

BACKGROUND

Apixaban is a factor Xa inhibitor with a limited therapeutic index that belongs to the family of oral direct anticoagulants. The pharmacokinetic (PK) behavior of apixaban may be altered in elderly populations and populations with renal or hepatic impairment, necessitating dosage adjustments.

METHODS

This study was conducted to examine how the physiologically based pharmacokinetic (PBPK) model describes the PKs of apixaban in adult and elderly populations and to determine the PKs of apixaban in elderly populations with renal and hepatic impairment. After PBPK models were constructed using the reported physicochemical properties of apixaban and clinical data, they were validated using data from clinical studies involving various dose ranges. Comparing predicted and observed blood concentration data and PK parameters was utilized to evaluate the model's fit performance.

RESULTS

Doses should be reduced to approximately 70% of the healthy adult population for the healthy elderly population to achieve the same PK exposure; approximately 88%, 71%, and 89% of that for the elderly populations with mild, moderate, and severe renal impairment, respectively; and approximately 96%, 81%, and 58% of that for the Child Pugh-A, Child Pugh-B, and Child Pugh-C hepatic impairment elderly populations, respectively to achieve the same PK exposure.

CONCLUSION

The findings indicate that the renal and hepatic function might be considered for apixaban therapy in Chinese elderly patients and the PBPK model can be used to optimize dosage regimens for specific populations.

Efficacy and safety of Apixaban for the prevention of thrombosis in arteriovenous grafts

This research aims to fill a vital gap in existing studies by evaluating the efficacy and safety of Apixaban, a direct oral anticoagulant, in the prevention of arteriovenous graft (AVG) thrombosis, thereby offering substantial insights into alternative anticoagulant options for hemodialysis patients. Conducted as a multi-center, randomized, double-blind, placebo-controlled trial, this study involved end-stage renal disease (ESRD) patients who had recently received polytetrafluoroethylene grafts. Participants were assigned to receive either Apixaban at a dose of 2.5 mg twice daily or a placebo. The primary outcome measure was the occurrence of graft thrombosis, while secondary outcomes focused on the incidence and severity of bleeding. Analytical methods included Kaplan-Meier estimates, Cox proportional hazards models, and conventional statistical tests. With 96 patients enrolled, the study found that Apixaban significantly reduced the incidence of AVG thrombosis compared to placebo (16.7% vs. 62.5%, P < 0.0001). Notably, this reduction in thrombosis incidence was not accompanied by an increase in bleeding events, thus affirming the safety profile of Apixaban as established in prior research. Apixaban is identified as an efficacious alternative to traditional anticoagulants in the prevention of AVG thrombosis among hemodialysis patients, representing a notable advancement in the care of individuals with ESRD. The results of this study support further investigations into the optimal dosing strategies specifically tailored for this patient demographic.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Efficacy and safety of direct oral anticoagulants vs vitamin K antagonists in patients with atrial fibrillation and end-stage renal disease on hemodialysis: A systematic review and meta-analysis

BACKGROUND

The prevalence of atrial fibrillation (AF) in individuals with end-stage renal disease (ESRD) on chronic hemodialysis is increasing. The optimal anticoagulant choice in this population is unclear since these patients were excluded from the pivotal randomized controlled trials (RCTs) of direct oral anticoagulants (DOACs) vs. vitamin K antagonists (VKAs) in the general AF population. We aimed to assess the efficacy and safety of DOACs vs. VKAs in patients with AF and ESRD on chronic hemodialysis through a systematic review and meta-analysis of all available evidence.

PATIENTS/METHODS

We performed a systematic search in MEDLINE and Scopus for RCTs or observational studies of patients with AF and ESRD on chronic hemodialysis who were treated with DOACs or VKAs. The outcomes of interest included ischemic stroke, the composite of ischemic stroke or systemic embolism, major bleeding, gastrointestinal bleeding, minor bleeding events and all-cause mortality.

RESULTS

Among 397 studies identified from the literature search, six studies (three RCTs and three observational studies) were included in the meta-analysis. Compared with VKA-treated patients, those treated with DOACs had similar risk of ischemic stroke (RR:0.76, 95% CI:0.41-1.41), ischemic stroke or systemic embolism (RR:0.65, 95% CI:0.38-1.10), major bleeding (RR:0.79, 95% CI:0.49-1.28) and all-cause death (RR:0.79, 95% CI:0.56-1.12). The risk of gastrointestinal bleeding was lower in DOAC- vs VKA-treated patients in three eligible observational studies (RR:0.73, 95% CI: 0.54-0.99, I2 = 79%) but this was not confirmed in two eligible RCTs (RR:0.69, 95% CI: 0.33-1.43, I2 = 0%).

CONCLUSIONS

Among AF patients with ESRD on chronic hemodialysis, the risk of ischemic stroke, ischemic stroke or systemic embolism, minor bleeding, major bleeding, and all-cause mortality is similar in patients treated with DOACs compared to VKAs. Given that the meta-analysis of RCTs on gastrointestinal bleeding did not confirm the results of the meta-analysis of the observational studies, it cannot be concluded that gastrointestinal bleeding is lower among DOAC-treated patients.

PROTOCOL REGISTRATION

PROSPERO CRD42023391966.

Effect of conventional hemodialysis on the apixaban plasma concentration

PURPOSE

Apixaban is a factor Xa inhibitor used in patients undergoing hemodialysis treatment. The objective of this study is to investigate the effect of hemodialysis on apixaban plasma concentrations.

METHODS

This observational study is on patients treated with apixaban 2.5 mg twice daily on conventional hemodialysis with standard low-molecular-weight heparin (LMWH) anticoagulation (nadroparin 3800-7600 IU). Plasma blood samples were collected before starting dialysis (t1), 2 h after starting dialysis (t2), and directly after dialysis (t3). Apixaban concentration was measured before and after dialysis. Anti-Xa activity was measured for all three samples.

RESULTS

A significant difference was observed between the apixaban concentration before and after dialysis (mean before dialysis 141.03 ng/mL; mean after dialysis 102.71 ng/mL; p = 0.003). Nonetheless, both apixaban plasma concentrations and anti-Xa levels remained within the reference range. Anti-Xa levels had a strong correlation with the apixaban concentrations (r = 0.935, p = 0.000). Thus, anti-Xa activity might be used as a surrogate for apixaban plasma concentration.

CONCLUSION

There seems to be no need for dose adjustments of apixaban; co-administration of LMWH next to apixaban might also be unnecessary.

Transcatheter left atrial appendage occlusion in patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

Chronic kidney disease (CKD) is a risk factor for embolic stroke, and many nonvalvular atrial fibrillation (NVAF) patients have concomitant CKD. Anticoagulation therapy can be challenging in CKD due to increased bleeding risk, and left atrial appendage occlusion (LAAO) may be a promising alternative.

OBJECTIVE

This systematic review aimed to consolidate current evidence on the safety and effectiveness of transcatheter LAAO in patients with CKD and end-stage renal disease (ESRD).

METHODS

Medline, Cochrane, and Embase databases were searched from inception to September 2, 2022. We conducted a meta-analysis if an outcome was evaluated in at least two similar studies.

RESULTS

We included 15 studies with 77,780 total patients. Of the 15 studies, 11 had a cohort design (five prospective and six retrospective), and four were case series. Patients with CKD were older and had a higher prevalence of comorbidities than non-CKD patients. The two groups did not differ in procedural failure rate, vascular complications, or pericardial tamponade. CKD patients exhibited higher odds of in-hospital acute kidney injury (AKI) and bleeding, longer-term bleeding, and mortality than those without CKD. The risk of in-hospital and longer-term cardioembolic events was similar between CKD and non-CKD populations (odds ratio = 1.01 [95% CI 0.70-1.15] and 1.05 [95% CI 0.55-2.00], respectively). Patients with ESRD had higher odds of in-hospital mortality and cardioembolic events than non-ESRD patients, with no differences in risk of pericardial tamponade.

CONCLUSIONS

Based on observational studies, LAAO may be an effective option to prevent cardioembolic events in CKD. However, CKD patients may have higher odds of AKI and in-hospital and long-term bleeding and mortality. The adverse clinical outcomes observed in CKD patients may be attributed to this population's high burden of comorbidities, especially among those with ERSD, rather than the LAAO procedure itself. To ensure maximum clinical benefit, careful patient selection, management, and surveillance involving multidisciplinary teams are essential for CKD patients undergoing LAAO. Transcatheter Left Atrial Appendage Occlusion (laao) Can Prevent Cardioembolic Events In Chronic Kidney Disease (ckd) Patients. However, Ckd Patients, Particularly Those With End-stage Renal Disease/dialysis (esrd), May Face Increased Odds Of Acute Kidney Injury, In-hospital And Long-term Bleeding, And Mortality. Notably, These Adverse Outcomes In Ckd Patients May Be Linked To Their High Comorbidity Burden, Particularly In Those With Esrd, Rather Than The Laao Procedure Itself. Careful Patient Selection, Management, And Surveillance Involving Multidisciplinary Teams Are Essential For Ckd Patients Undergoing Laao To Ensure Maximum Clinical Benefit Transcatheter left atrial appendage occlusion (LAAO) can prevent cardioembolic events in chronic kidney disease (CKD) patients. However, CKD patients, particularly those with end-stage renal disease/dialysis (ESRD), may face increased odds of acute kidney injury, in-hospital and long-term bleeding, and mortality. Notably, these adverse outcomes in CKD patients may be linked to their high comorbidity burden, particularly in those with ESRD, rather than the LAAO procedure itself. Careful patient selection, management, and surveillance involving multidisciplinary teams are essential for CKD patients undergoing LAAO to ensure maximum clinical benefit.

Effectiveness and safety of direct oral anticoagulants versus warfarin in patients with atrial fibrillation and advanced kidney disease

BACKGROUND

The effectiveness and safety of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) and advanced kidney disease (AKD) has not been fully established.

OBJECTIVES

To determine the effectiveness and safety related to pooled or specific DOACs to that with warfarin in patients with AF and AKD.

METHODS

Patients with AF and AKD (estimated glomerular filtration rate < 30 mL/min) who received DOAC or warfarin from July 2011 to December 2020 were retrospectively identified in a medical center in Taiwan. Primary outcomes were hospitalized for stroke/systemic embolism and major bleeding. Secondary outcomes included any ischemia and any bleeding.

RESULTS

A total of 1,011 patients were recruited, of whom 809 (80.0%) were in the DOACs group (15.3% dabigatran, 25.4% rivaroxaban, 25.2% apixaban, and 14.1% edoxaban), and 202 (20.0%) in the warfarin group. DOACs had considerably lower risks of stroke/systemic embolism (adjusted hazard ratio [aHR] 0.29; 95% CI, 0.09-0.97) and any ischemia (aHR, 0.42; 95% CI, 0.22-0.79), but had comparable risks of major bleeding (aHR, 0.99; 95% CI, 0.34-2.92) and any bleeding (aHR, 0.74; 95% CI, 0.50-1.09) than warfarin. Apixaban was linked to considerably lower risks of any ischemia (aHR, 0.13; 95% CI, 0.04-0.48) and any bleeding (aHR, 0.53; 95% CI, 0.28-0.99) than warfarin.

CONCLUSION

Among patients with AF and AKD, DOACs were linked to a lower risk of ischemic events, and apixaban was linked to a lower risk of any ischemia and any bleeding than warfarin.

Bleeding Risk in Hemodialysis Patients

Cardiovascular diseases are highly prevalent among patients on dialysis. For these diseases, antiplatelets and antithrombotic therapies including heparin, vitamin K antagonists, and direct oral anticoagulants, are being used. However, the benefit-risk balance of these therapies could differ for dialysis patients compared with the general population. This review article focuses on the bleeding risk associated with the use of heparin, antiplatelets, vitamin K antagonists, and direct oral anticoagulants in patients receiving hemodialysis.

Prescription of DOACs in Patients with Atrial Fibrillation at Different Stages of Renal Insufficiency

Atrial fibrillation (AF) and renal insufficiency often coexist and are increasingly prevalent with advancing age. Both the risk of thromboembolic events and bleeding propensity are higher in patients with AF and impaired renal function versus those with good renal health. Direct oral anticoagulants (DOACs) are being increasingly preferred over vitamin K antagonists (VKAs) in the treatment of patients with AF and impaired renal function as VKAs may accelerate progression of chronic kidney disease. DOACs, however, are eliminated by the kidneys to varying degrees, and their dosages must be adapted in accordance with renal function. Since creatinine clearance (CrCl) monitoring is recommended in patients with AF receiving DOAC therapy, CrCl must be routinely monitored in patients at the start and during the course of anticoagulation to avoid deviation from Summary of Product Characteristics dosage specifications. This review article provides an overview of current knowledge on the selection and dose of DOACs including apixaban, dabigatran, edoxaban and rivaroxaban in AF patients at different stages of renal insufficiency, with a special focus on elderly patients with comorbidities and receiving multiple medications. The groups discussed in this review include patients with varying levels of CrCl including hyperfiltration or CrCl > 90 ml/min, CrCl < 90-50 ml/min, CrCl < 50-30 ml/min, CrCl < 30-15 ml/min and end-stage renal disease or on dialysis.

Kidney function and the comparative effectiveness and safety of direct oral anticoagulants vs. warfarin in adults with atrial fibrillation: a multicenter observational study

AIMS

The aim of this study was to determine the comparative effectiveness and safety of direct oral anticoagulants (DOACs) and warfarin in adults with atrial fibrillation (AF) by level of kidney function.

METHODS AND RESULTS

We pooled findings from five retrospective cohorts (2011-18) across Australia and Canada of adults with; a new dispensation for a DOAC or warfarin, an AF diagnosis, and a measure of baseline estimated glomerular filtration rate (eGFR). The outcomes of interest, within 1 year from the cohort entry date, were: (1) the composite of all-cause death, first hospitalization for ischaemic stroke, or transient ischaemic attack (effectiveness), and (2) first hospitalization for major bleeding defined as an intracranial, upper or lower gastrointestinal, or other bleeding (safety). Cox models were used to examine the association of a DOAC vs. warfarin with outcomes, after 1:1 matching via a propensity score. Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2. A total of 74 542 patients were included in the matched analysis. DOAC initiation was associated with greater or similar effectiveness compared with warfarin initiation across all eGFR categories [pooled HRs (95% CIs) for eGFR categories: 0.74(0.69-0.79), 0.76(0.54-1.07), 0.68(0.61-0.75) and 0.86(0.76-0.98)], respectively. DOAC initiation was associated with lower or similar risk of major bleeding than warfarin initiation [pooled HRs (95% CIs): 0.75(0.65-0.86), 0.81(0.65-1.01), 0.82(0.66-1.02), and 0.71(0.52-0.99), respectively). Associations between DOAC initiation, compared with warfarin initiation, and study outcomes were not modified by eGFR category.

CONCLUSION

DOAC use, compared with warfarin use, was associated with a lower or similar risk of all-cause death, ischaemic stroke, and transient ischaemic attack and also a lower or similar risk of major bleeding across all levels of kidney function.

Safety and efficacy of apixaban versus low-molecular weight heparin or vitamin-K antagonists for venous thromboembolism treatment in patients with severe renal failure: A systematic review and meta-analysis

INTRODUCTION

Chronic kidney disease is an independent risk factor for venous thromboembolism (VTE). Traditionally, Low Molecular Weight Heparin (LMWH) followed by warfarin has been the conventional therapy for VTE treatment. Direct oral anticoagulants (DOACs), including apixaban, have shown several advantages over the traditional therapy in individuals with normal kidney function. This meta-analysis aims to review the safety and efficacy of apixaban compared to warfarin or LMWH for the treatment of VTE in severe renal failure.

METHOD

We conducted literature search in PubMed, Embase, and Cochrane databases. Retrospective observational studies involving clinical effectiveness and safety outcomes of apixaban compared to warfarin in adult patients with an estimated glomerular filtration rate (eGFR) <30 mL/min/m2 or on dialysis were included.

RESULTS

Eight studies were included in the analysis. Significant reduction in VTE recurrence observed in apixaban compared to warfarin (RR, 0.65; 95 % CI, 0.43-0.98; P = 0.04; I2 = 78 %). No significant difference in all-cause mortality between apixaban and warfarin (RR, 0.99; 95 % CI, 0.91-1.07; P = 0.74; I2 = 0 %). Apixaban showed a significantly lower rate of major bleeding (RR, 0.72; 95 % CI, 0.62-0.84; P < 0.0001; I2 = 34 %) and minor bleeding events (RR, 0.42; 95 % CI, 0.21-0.86; P = 0.02; I2 = 10 %) compared to warfarin. No significant difference observed in clinically relevant non-major bleeding between apixaban and warfarin (RR, 0.81; 95 % CI, 0.65-1.00; P = 0.05; I2 = 67 %).

CONCLUSION

Apixaban was favored over warfarin for treating VTE in severe renal failure, reducing VTE recurrence and bleeding risk. No differences were observed in all-cause mortality and CRNMB events. More evidence is required due to limited RCTs and prospective studies.

Pharmacokinetics of Apixaban Among Peritoneal Dialysis Patients

Rationale & Objective

The efficacy and safety profile of apixaban remains uncertain in patients receiving peritoneal dialysis (PD) despite increasing use in this population. Accordingly, we assessed the pharmacokinetics of apixaban among patients receiving PD.

Study Design

A pharmacokinetics study in a single center. Patients recruited received 1 week of apixaban at 2.5 mg twice a day to reach steady state. Serial blood samples were then taken before and after the last dose for pharmacokinetics analysis of apixaban.

Setting & Participants

Ten stable PD patients with atrial fibrillation in an outpatient setting.

Analytical Approach/Outcomes

Pharmacokinetic parameters including the area under the concentration-time curve from time 0 to 12 hours after the last dose of apixaban (AUC0-12), peak concentration, trough level, time to peak apixaban concentration, half-life, and drug clearance were analyzed.

Results

There was a wide variation in the range of apixaban concentration across the 10 patients. The AUC0-12 for the PD group was significantly higher than those reported previously for hemodialysis patients or healthy individuals. Three patients had a supratherapeutic peak concentration whereas 2 patients had a supratherapeutic trough level as compared with the pharmacokinetic parameter in healthy individuals taking equivalent therapeutic dosage.

Limitations

Small sample size with short study duration limits the ability to ascertain the true bleeding risk and to detect any clinical outcomes. Results may be limited to Asian populations only.

Conclusions

A proportion of PD patients had supratherapeutic levels even when the reduced dosage 2.5 mg twice a day was used. Given the large interindividual variation in the drug level, therapeutic drug monitoring should be done if available. Otherwise, one should start the drug at reduced doses with caution and with more frequent clinical monitoring for any signs of bleeding.

Extracorporeal hemoadsorption therapy as a potential therapeutic option for rapid removal of Apixaban in high risk-surgical patients: a case report

BACKGROUND

Apixaban is a non-vitamin K antagonist oral anticoagulant (NOACs) recently emerged as an effective alternative to conventional vitamin K antagonists (VKAs) in the treatment of several thromboembolic disorders. However, in case of overdose or in patients requiring emergency surgery there is a high bleeding rate and severe adverse side effects due to the absence of an antidote. There is promising data from in vitro and clinical studies, that certain antithrombotic agents (that is Rivaroxaban and Ticagrelor) have been successfully removed by the extracorporeal hemoadsorption therapy CytoSorb. Here, we present the case of a patient successfully treated with CytoSorb as a kind of antidote to enable emergency surgery for bilateral nephrostomy.

CASE PRESENTATION

A 82-year-old Caucasian man was admitted to the Emergency Room with acute kidney injury (AKI) in the context of severe bilateral hydroureteronephrosis. The patient's medical history included chronic obstructive pulmonary disease, arterial hypertension, atrial fibrillation (anticoagulated with Apixaban) and a locally advanced prostate adenocarcinoma treated with trans-ureteral resection of the bladder and radiotherapy in the previous months. The indication for a bilateral nephrostomy could not be considered immediately given the major bleeding risk due to Apixaban, which was discontinued and replaced with calciparin. After 36 hours of continuous renal replacement therapy (CRRT), the Apixaban blood level was still elevated and it was decided to install CytoSorb into the running CRRT to accelerate the drug clearance. After 2 hours 30 minutes, there was good reduction of Apixaban from 139 to 72 ng/ml (reduction rate of 48.2%) registered, and this allowed for an easy placement of bilateral nephrostomies without complications. Four days after surgery renal function parameters further normalized, the patient did not require additional dialysis treatments and Apixaban therapy was prescribed again once the patient returned home.

CONCLUSIONS

In this case we report the findings of a patient with post-renal AKI requiring emergency nephrostomy placement while on chronic anticoagulation with Apixaban therapy. Combined treatment with CRRT and CytoSorb was associated with the rapid and effective removal of Apixaban allowing for prompt and urgent surgery while simultaneously ensuring the low risk of bleeding as well as an uneventful post-operative course.

Pharmacist Practice Patterns Regarding Direct Oral Anticoagulants for Treatment of Venous Thromboembolism

Background: Direct oral anticoagulants (DOACs) are increasingly prescribed for the treatment of venous thromboembolism (VTE). However, little is known regarding pharmacists' practice patterns and preferences in clinical areas of contention, such as initiation dosing, obesity, and renal impairment. Objective: To determine pharmacist trends in practice regarding DOACs for the treatment of VTE overall and within areas of clinical controversy. Methods: An electronic survey was distributed to pharmacists in the United States through national and state pharmacy organizations. Responses were collected for 30 days. Results: One hundred fifty-three complete responses were submitted. The majority of pharmacists preferred apixaban (90.2%) for the oral treatment of venous thromboembolism. When initiating apixaban or rivaroxaban for a new VTE, 76% and 64% of pharmacists surveyed, respectively, state the duration of the initiation dose phases are reduced if the patient received parenteral anticoagulation. Fifty-eight percent of pharmacists used body mass index to evaluate the appropriateness of DOACs in obese patients whereas 42% used total body weight. Preference for rivaroxaban (31.4%) was higher in this population compared to the global population (10%). Apixaban was preferred for patients with renal impairment (92.2%). However, as creatinine clearance as calculated by the Cockcroft-Gault equation (CrCl) reduced to ≤15 milliliters/minute (mL/min), preference for warfarin increased (36%). Conclusion: This national survey of pharmacists demonstrated an overall preference for apixaban and significant variability in practice patterns regarding DOACs for patients with new VTE, patients with obesity, and patients with renal impairment. Further research is warranted to evaluate the efficacy and safety of DOAC initiation dosing phase modifications. Prospective evaluations of DOACs in obese and renal dysfunction populations would confirm the safety and efficacy of DOACs in these populations.

A Review of the Safety and Efficacy of Apixaban in Patients With Severe Renal Impairment

Background Apixaban is a direct-acting oral anticoagulant (DOAC) used to treat or prevent thromboembolic events. Renal impairment limits DOAC use. Studies supporting Food and Drug Administration (FDA)-approval for apixaban did not include patients with a creatinine clearance < 25 mL/min. Consequently, limited guidance for use in end-stage renal disease (ESRD) exists in the package insert. An in-depth literature search reveals substantial evidence supporting the safety and effectiveness of apixaban in ESRD. Clinicians must have access to this evidence so that patients in need of apixaban therapy are appropriately managed. Objective To provide an up-to-date review of literature surrounding the safety and effectiveness of apixaban in patients with ESRD. Data Sources A PubMed search of research studies published through November 2021 was performed using a combination of the following terms: apixaban, severe renal impairment, end-stage renal disease, DOACs, safety, effectiveness, atrial fibrillation, anticoagulation. Study Selection/Data Extraction Relevant original research, review articles, and guidance recommendations were assessed for the use of apixaban in patients with ESRD. References from the above literature were also evaluated. Articles were selected for inclusion based on relevance to the topic, detailed methods, and complete results. Data Synthesis Numerous studies exist supporting the safety and effectiveness of apixaban in patients with ESRD who may or may not be on dialysis. Conclusion Multiple studies suggest that apixaban is possibly associated with a lower prevalence of bleeding and thromboembolic events compared with warfarin therapy in patients with ESRD and can be safely initiated in those within this sub-group who require anticoagulation with a DOAC. Clinicians should monitor for signs of bleeding throughout the duration of therapy.

Personalizing Direct Oral Anticoagulant Therapy for a Diverse Population: Role of Race, Kidney Function, Drug Interactions, and Pharmacogenetics

Oral anticoagulants (OACs) are commonly used to reduce the risk of venous thromboembolism and the risk of stroke in patients with atrial fibrillation. Endorsed by the American Heart Association, American College of Cardiology, and the European Society of Cardiology, direct oral anticoagulants (DOACs) have displaced warfarin as the OAC of choice for both conditions, due to improved safety profiles, fewer drug-drug and drug-diet interactions, and lack of monitoring requirements. Despite their widespread use and improved safety over warfarin, DOAC-related bleeding remains a major concern for patients. DOACs have stable pharmacokinetics and pharmacodynamics; however, variability in DOAC response is common and may be attributed to numerous factors, including patient-specific factors, concomitant medications, comorbid conditions, and genetics. Although DOAC randomized controlled trials included patients of varying ages and levels of kidney function, they failed to include patients of diverse ancestries. Additionally, current evidence to support DOAC pharmacogenetic associations have primarily been derived from European and Asian individuals. Given differences in genotype frequencies and disease burden among patients of different biogeographic groups, future research must engage diverse populations to assess and quantify the impact of predictors on DOAC response. Current under-representation of patients from diverse racial groups does not allow for proper generalization of the influence of clinical and genetic factors in relation to DOAC variability. Herein, we discuss factors affecting DOAC response, such as age, sex, weight, kidney function, drug interactions, and pharmacogenetics, while offering a new perspective on the need for further research including frequently excluded groups.

A Description of Apixaban Dosing Patterns for Treatment or Prevention of Thrombotic Events in Hospitalized Patients on Dialysis

Introduction: Apixaban is currently the only oral direct factor Xa inhibitor approved for treatment and prevention of venous thromboembolism (VTE) in patients on hemodialysis. Exclusion of dialysis patients from major clinical trials results in prescriber uncertainty regarding the optimal dose of apixaban for VTE treatment in this population. This study sought to characterize the variance in apixaban prescribing patterns for thrombotic indications other than atrial fibrillation. Methods: This retrospective, multi-center, descriptive study analyzed apixaban dosing patterns for hospitalized chronic dialysis patients with history of thrombosis. The primary outcome was incidence of deviation from manufacturer recommendations for dosing, assessed for either a new start or receipt prior to hospitalization. Secondary outcomes included observation of recurrent thrombotic and bleeding event rates during subsequent hospitalizations. Patients were analyzed into subgroups according to type of thrombotic indication for treatment. Data are reported with descriptive statistics. Results: A total of 101 patients were included. Deviations in recommended dosing were observed in 53 of 80 (66.2%) patients receiving apixaban for treatment of acute or chronic thrombosis. Of 44 patients started on apixaban during hospitalization for the indication of acute VTE, a dose deviation was observed in 79.5% of patients. Rates of rehospitalization for recurrent thrombotic events and bleeding were 11.8% and 9.9%, respectively. Conclusion: Variation in apixaban prescribing practices for the treatment of VTE in dialysis patients is common, suggesting an urgent need for prospective studies and updated dosing guidance to optimize safety with apixaban use in this population.

The 5 most frequently asked questions about factor Xa inhibitors

Direct oral anticoagulants (DOACs) are commonly used oral factor Xa inhibitors in recent years. However, in some special clinical situations, the appropriate use of these anticoagulants may be of concern. In this article, we address the 5 commonly asked questions regarding their use for the treatment of venous thromboembolism, including in the setting of obesity, renal impairment, gastrointestinal (GI) malignancy, catheter-related thrombosis, and drug-drug interactions. Data on the use of DOACs in the presence of significant obesity or renal failure are mainly observational. Some DOACs are shown to have an increased risk of bleeding in patients with unresected luminal GI malignancy but not others, so selection of appropriate patients is the key. Furthermore, literature on the use of DOACs for catheter-related thrombosis or when drug-drug interactions are of concern is limited, and more research is welcome.

Plasma apixaban levels in Chinese patients with chronic kidney disease-Relationship with renal function and bleeding complications

Introduction: Accumulation of apixaban in plasma is a major concern in patients with chronic kidney disease (CKD). Studies that investigated plasma apixaban level in CKD patients and its association with clinically significant events are scarce. Methods: Patients with CKD Stage 1-4 who were taking apixaban, either 2.5 mg BD or 5 mg BD were recruited. The peak and trough plasma apixaban level were measured after 2 h and 12 h of last dose respectively. The results were correlated with renal function and clinical events during the period of follow-up from 1 January 2018 to 31 October 2021. Results: 141 patients (CKD Stage 1, n = 12; Stage 2, n = 74; Stage 3, n = 48, stage 4, n = 7) were included for analysis. The plasma peak and trough apixaban were significantly higher in patients with CKD stage 3 when compared with those having CKD stage 2 and 1 (peak levels: 223.4 ± 107.8 ng/ml vs. 161.0 ± 55.2 ng/ml vs. 126.6 ± 30.2 ng/ml; trough levels: 118.3 ± 67.9 ng/ml vs. 81.2 ± 33.0 ng/ml vs. 51.9 ± 31.1 ng/ml, p < 0.05 or all) in patients taking 5 mg BD. Plasma trough apixaban level was negatively correlated with eGFR in patients taking 5 mg BD (r ² = -0.174, p < 0.001) and 2.5 mg BD (r ² = -0.215, p < 0.05). The plasma peak and trough apixaban level correlated with PT (r ² = 0.065, p = 0.003 and r ² = 0.096, p < 0.01 respectively). Multivariate analysis showed that plasma trough apixaban levels were associated with the risk of bleeding complications (Odd ratio: 1.011, 95% CI:1.002-1.021, p = 0.023). Conclusion: The plasma apixaban level shows a trend of increase with worsening renal function, and an increase in the plasma apixaban level is suggestive of an increased risk of bleeding complications in patients with CKD. Further large-scale prospective studies are needed to evaluate relationship between plasma apixaban level and renal function as well as safety outcome in CKD patients. Moreover, the role of drug level monitoring should be prospectively evaluated for dosage optimization and the minimization of bleeding risks in CKD patients.

Apixaban for Patients With Atrial Fibrillation on Hemodialysis: A Multicenter Randomized Controlled Trial

BACKGROUND

There are no randomized data evaluating the safety or efficacy of apixaban for stroke prevention in patients with end-stage kidney disease on hemodialysis and with atrial fibrillation (AF).

METHODS

The RENAL-AF trial (Renal Hemodialysis Patients Allocated Apixaban Versus Warfarin in Atrial Fibrillation) was a prospective, randomized, open-label, blinded-outcome evaluation (PROBE) of apixaban versus warfarin in patients receiving hemodialysis with AF and a CHA2DS2-VASc score ≥2. Patients were randomly assigned 1:1 to 5 mg of apixaban twice daily (2.5 mg twice daily for patients ≥80 years of age, weight ≤60 kg, or both) or dose-adjusted warfarin. The primary outcome was time to major or clinically relevant nonmajor bleeding. Secondary outcomes included stroke, mortality, and apixaban pharmacokinetics. Pharmacokinetic sampling was day 1, day 3, and month 1.

RESULTS

From January 2017 through January 2019, 154 patients were randomly assigned to apixaban (n=82) or warfarin (n=72). The trial stopped prematurely because of enrollment challenges. Time in therapeutic range (international normalized ratio, 2.0-3.0) for warfarin-treated patients was 44% (interquartile range, 23%-59%). The 1-year rates for major or clinically relevant nonmajor bleeding were 32% and 26% in apixaban and warfarin groups, respectively (hazard ratio, 1.20 [95% CI, 0.63-2.30]), whereas 1-year rates for stroke or systemic embolism were 3.0% and 3.3% in apixaban and warfarin groups, respectively. Death was the most common major event in the apixaban (21 patients [26%]) and warfarin (13 patients [18%]) arms. The pharmacokinetic substudy enrolled the target 50 patients. Median steady-state 12-hour area under the curve was 2475 ng/mL×h (10th to 90th percentiles, 1342-3285) for 5 mg of apixaban twice daily and 1269 ng/mL×h (10th to 90th percentiles, 615-1946) for 2.5 mg of apixaban twice daily. There was substantial overlap between minimum apixaban blood concentration, 12-hour area under the curve, and maximum apixaban blood concentration for patients with and without a major or clinically relevant nonmajor bleeding event.

CONCLUSIONS

There was inadequate power to draw any conclusion regarding rates of major or clinically relevant nonmajor bleeding comparing apixaban and warfarin in patients with AF and end-stage kidney disease on hemodialysis. Clinically relevant bleeding events were ≈10-fold more frequent than stroke or systemic embolism among this population on anticoagulation, highlighting the need for future randomized studies evaluating the risks versus benefits of anticoagulation among patients with AF and end-stage kidney disease on hemodialysis.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02942407.

Anticoagulation for Stroke Prevention of Concomitant Atrial Fibrillation and End-Stage Renal Disease: Insights of Cardiologists and Nephrologists From India

Introduction Patients with concomitant atrial fibrillation (AF) and end-stage renal disease (ESRD) are at increased risk of thrombosis and bleeding. Diligent anticoagulant therapy that prevents major bleeding is essential for stroke prevention. There is a dearth of evidence and guidance on anticoagulation in this patient subset. Methods A validated questionnaire was sent to 500 physicians across India. Anonymized responses from 353 consenting physicians (275 cardiologists and 78 nephrologists) were analyzed. Results Most physicians opined that the risk of progression of chronic kidney disease (CKD) stages 2-4 to ESRD was 1-5%, and that >10% of patients with ESRD had concomitant AF. Most physicians perceived that the risk of ischemic stroke, major bleeding, and mortality was 30-40%, <15%, and >40% respectively in patients with concomitant AF and ESRD. The first critical goal for the management of these patients was 'reduction of thrombotic risk', followed by 'prevention of bleeding' and finally 'prevention of ESRD progression' (72.0%, 68.0%, and 67.1% participants, respectively). Most participating physicians (93.8%) preferred non-vitamin K antagonist oral anticoagulants (NOACs) over warfarin for stroke prevention, and most of the participating physicians (94.9%) preferred an adjusted dose rather than the standard dose of the NOAC. Most of the responses were similar between cardiologists and nephrologists. Conclusion According to the survey response, patients with concomitant AF and ESRD have an increased risk of thrombosis, bleeding, and mortality. NOACs with dose adjustment are the preferred modality for stroke prevention among cardiologists and nephrologists in India, with the primary goal of preventing thrombotic events.

Safety and Efficacy of Apixaban vs Warfarin in Patients With Stage 4 and 5 Chronic Kidney Disease: A Systematic Review

Warfarin has been an anticoagulant of choice in patients with advanced Chronic Kidney Diseases (CKD) at stages 4 and 5 for decades, but with the advent of Novel Oral Anticoagulants (NOACs), there has been a sharp rise in their prescriptions. Among all NOACS, apixaban is the least reliant on kidney function and is a very popular choice for this patient population. However, being utilized extensively, most of the landmark trials evaluating the safety and efficacy of apixaban excluded patients with Creatinine Clearance (CrCl) <25mL/min/1.73 m² or Serum Creatinine (SCr) ≥2.5mg/dL. Its approval for advanced CKD patients came from limited pharmacokinetic data only. We conducted a systematic review comparing the safety and efficacy of apixaban to warfarin in patients with stage 4 and 5 CKD and on dialysis. We queried major research literature databases, including MEDLINE, PubMed, PubMed Central (PMC), Cochrane Central, and ScienceDirect to find relevant articles without any time or language restrictions. After screening and quality checks, we identified 11 studies relevant to our research question, of which nine were retrospective cohort studies, one was a post-hoc analysis of a randomized controlled trial (RCT), and one was an RCT. The included studies had a total of 27,007 patients, with 4,335 patients taking apixaban and 22,672 on warfarin. The results indicate that the overall efficacy of apixaban was equivalent to warfarin for the prevention of stroke, systemic embolization, and recurrent venous thromboembolism, but apixaban showed an equivalent and, in some studies, better safety profile than warfarin concerning the occurrence of bleeding. Apixaban may hence be considered a reasonable alternative to warfarin in patients with Stage 4 or 5 CKD and receiving dialysis. In light of the reviewed articles, we conclude that apixaban has similar efficacy and somewhat superior safety profile to warfarin, with more randomized controlled trials required to add to the evidence.

Elevated International Normalized Ratio Due to Apixaban in Patient With End-Stage Renal Disease on Hemodialysis

Apixaban is known to prolong international normalized ratio (INR) per some observational and in vitro studies. In patients with elevated INR secondary to apixaban use, median INR of 1.4-1.7 has been reported. Extreme elevation in INR is rare with apixaban. In patients with end-stage renal disease (ESRD) on hemodialysis (HD), there are no labeled indications for apixaban use; however, there are some pharmacokinetic data supporting its use in such patients.

We present a case of a 68-year-old Hispanic man with ESRD who presented to the emergency room (ER) with INR of 27.42. INR testing was done as a part of routine workup in rehabilitation facility. Medication list was reviewed and included apixaban 2.5 mg twice daily which was recently started for postoperative thromboprophylaxis. INR testing was repeated for confirmation in ER and was reported as >18.5 and prothrombin time >200 seconds. His liver function tests were stable as compared to baseline testing five days ago with normal bilirubin, low normal transaminases, and mild hypoalbuminemia. The patient didn’t have any active bleeding. An elevation of INR to >20 with apixaban is a rare event. No other factors including patient characteristics, laboratory results, co-existing conditions, or other medications except the direct oral anticoagulant (DOAC) were found to be responsible for elevated INR. Liver cirrhosis or vitamin K deficiency as cause for INR elevation was ruled out as the baseline INR was normal prior to starting apixaban, liver function tests were stable and INR normalized again shortly after discontinuing the medication. Plasma concentration of DOACs has been found to be correlating with the INR according to a pharmacokinetic study which potentially means that the high INR likely was secondary to high serum concentration of apixaban in this patient. However, INR monitoring is not recommended for monitoring anticoagulant activity of DOACs. As of note, renal clearance accounts for 27% of apixaban clearance.

Pharmacokinetic studies have concluded that half dose apixaban, i.e., 2.5 mg twice daily in patients on hemodialysis (dose used in this case) results in drug exposure similar to that of the standard dose of 5 mg twice daily in patients with preserved renal function. Future studies are necessary to address questions about safety of DOACs in patients with ESRD, further elucidate the clinical significance of such high INR values associated with DOACs, and establish appropriate management guidelines. Andexanet alfa has since been approved for apixaban reversal in patients with life-threatening bleeding; however, would not be indicated in such cases when there is no evidence of bleeding.

Evaluating pharmacokinetic drug-drug interactions of direct oral anticoagulants in patients with renal dysfunction

INTRODUCTION

Drug transporters, metabolic enzymes, and renal clearance play significant roles in the pharmacokinetics of direct oral anticoagulants (DOACs). Recommendations for DOAC drug-drug interactions (DDIs) by the product labeling are limited to selected CYP3A4 and P-glycoprotein inhibitors and lack considerations for concomitant renal dysfunction.

AREAS COVERED

This review focuses on: 1) current recommendations for the management of pharmacokinetic DOAC DDIs and the evidence used to support them; 2) alterations in DOAC exposure in the setting of concomitant DDIs and mild, moderate, and severe renal impairment; 3) clinical outcomes associated with this combination; and 4) expert recommendations for the management of pharmacokinetic DOAC DDIs. English-language, full-text articles on apixaban, dabigatran, rivaroxaban, and edoxaban with a publication date up to 30 September 2021 were retrieved from PubMed.

EXPERT OPINION

Given the lack of supporting clinical data, empiric dose adjustments based on pharmacokinetic data alone should be avoided. When a considerable increase in a DOAC exposure is anticipated, it may be advisable to use an alternative DOAC or anticoagulant from a different class. Future research on identification of DOAC therapeutic ranges and target patient populations is needed to inform clinical utility of DOAC level monitoring to guide the management of DDIs.

Non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients with advanced chronic kidney and liver diseases

Advanced chronic kidney disease (CKD) or chronic liver disease (CLD) is frequent in patients with atrial fibrillation (AF) because of their common risk factors. Chronic kidney disease and CLD superimposed on AF are associated with increased risks of thrombosis and bleeding, which further complicates the use of oral anticoagulants (OACs). Because currently approved non-vitamin K antagonist oral anticoagulants (NOACs) undergo certain degrees of metabolism and clearance in the liver and kidney, increased exposure to medications and risk of bleeding are major concerns with the use of NOACs in patients with advanced CKD and CLD. Besides, these patients were mostly excluded from landmark trials of NOACs and related cohort studies are also limited. Therefore, the optimal strategy for the use of NOACs in this population remains unclear. This review would go through current evidence regarding the safety and efficacy of NOACs in AF patients with advanced CKD and CLD and provide a comprehensive discussion for clinical practices.

Coagulation markers in patients with venous thromboembolism treated with 10 mg apixaban twice daily

Apixaban is used to treat venous thromboembolism (VTE) at 10 mg twice daily (BID) for 7 days, followed by 5 mg BID without dose adjustment, and non-valvular atrial fibrillation (NVAF) at 5 mg BID or 2.5 mg BID with dose adjustment criteria (DAC) including age, body weight, and renal function. The anti-factor Xa activity (AXA), prothrombin time (PT), and activated partial thromboplastin time (APTT) in patients with VTE receiving 10 mg BID of apixaban remains unclear. Twenty-six patients (70.8±15.4 years, 10 males) with VTE receiving 10 mg BID of apixaban were enrolled. The patients were divided into two groups based on whether they met the DAC of NVAF: DAC group (n=8) and non-DAC group (n=18). Trough and peak AXA values, PT, and APTT were measured at 10 mg BID dosage and then at 5 mg BID dosage. Coagulation markers in recipients of 10 mg BID therapy were significantly higher than those of 5 mg BID recipients. A significant and strong positive correlation was observed between AXA and PT at trough and peak times. The AXA values and PT in the DAC group were significantly higher than those in the non-DAC group. No significant inter-group differences were seen in APTT. This study provides the first report of AXA distribution in VTE patients receiving 10 mg BID of apixaban. Our findings indicate that coagulation markers may differ in patients with VTE-prescribed higher doses of apixaban and a DAC may be warranted in such patients.

Low Exposure to Direct Oral Anticoagulants Is Associated with Ischemic Stroke and Its Severity

Background and purpose

In acute stroke patients, plasma concentrations of direct oral anticoagulants (DOAC) at hospital admission only poorly mirror DOAC exposure or the coagulation status at the time of the event. Here, we evaluated whether DOAC exposure and DOAC plasma concentration at the time of transient ischemic attacks (TIA) and ischemic strokes correlate with their likelihood of occurrence.

Methods

Prospectively, consecutive DOAC patients with acute ischemic stroke or TIA were included. Admission DOAC plasma concentrations were measured by ultraperformance liquid chromatography– tandem mass spectrometry. Individual DOAC exposure (area under the curve) and DOAC concentrations at event onset were derived from population pharmacokinetic analyses.

Results

DOAC exposure was successfully modeled in 211 patients (ischemic stroke 74.4%, TIA 25.6%). Compared to published values, 63.0% had relatively lower DOAC exposure and they more often received lower DOAC doses than recommended (odds ratio [OR], 2.125; 95% confidence interval [CI], 1.039 to 4.560; P=0.044). These patients more likely suffered ischemic strokes than TIA (OR, 2.411; 95% CI, 1.254 to 4.638; P=0.008) and their strokes were more severe (slope, 3.161; 95% CI, 0.741 to 5.58; P=0.011). Low relative DOAC concentrations at event onset were likewise associated with ischemic strokes (OR, 4.123; 95% CI, 1.834 to 9.268; P=0.001), but not to stroke severity (P=0.272). DOAC exposure had a higher explanatory value for stroke severity than concentrations at event.

Conclusions

Low DOAC exposure is strongly associated to ischemic stroke and its severity. By monitoring DOAC plasma concentrations, patients prone to ischemic stroke might be identified.

Safety and Efficacy of DOACs in Patients with Advanced and End-Stage Renal Disease

The prevalence of chronic kidney disease (CKD) is increasing due to the aging of the population and multiplication of risk factors, such as hypertension, arteriosclerosis and obesity. Impaired renal function increases both the risk of bleeding and thrombosis. There are two groups of orally administered drugs to prevent thromboembolic events in patients with CKD who require anticoagulation: vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs). Although VKAs remain the first-line treatment in patients with advanced CKD, treatment with VKAs is challenging due to difficulties in maintaining the appropriate anticoagulation level, tendency to accelerate vascular calcification and faster progression of CKD in patients treated with VKAs. On the other hand, the pleiotropic effect of DOACs, including vascular protection and anti-inflammatory properties along with comparable efficacy and safety of treatment with DOACs, compared to VKAs observed in preliminary reports encourages the use of DOACs in patients with CKD. This review summarizes the available data on the efficacy and safety of DOACs in patients with CKD and provides recommendations regarding the choice of the optimal drug and dosage depending on the CKD stage.

Therapeutic Strategies for Disseminated Intravascular Coagulation Associated with Aortic Aneurysm

Aortic aneurysms are sometimes associated with enhanced-fibrinolytic-type disseminated intravascular coagulation (DIC). In enhanced-fibrinolytic-type DIC, both coagulation and fibrinolysis are markedly activated. Typical cases show decreased platelet counts and fibrinogen levels, increased concentrations of fibrin/fibrinogen degradation products (FDP) and D-dimer, and increased FDP/D-dimer ratios. Thrombin-antithrombin complex or prothrombin fragment 1 + 2, as markers of coagulation activation, and plasmin-α₂ plasmin inhibitor complex, a marker of fibrinolytic activation, are all markedly increased. Prolongation of prothrombin time (PT) is not so obvious, and the activated partial thromboplastin time (APTT) is rather shortened in some cases. As a result, DIC can be neither diagnosed nor excluded based on PT and APTT alone. Many of the factors involved in coagulation and fibrinolysis activation are serine proteases. Treatment of enhanced-fibrinolytic-type DIC requires consideration of how to control the function of these serine proteases. The cornerstone of DIC treatment is treatment of the underlying pathology. However, in some cases surgery is either not possible or exacerbates the DIC associated with aortic aneurysm. In such cases, pharmacotherapy becomes even more important. Unfractionated heparin, other heparins, synthetic protease inhibitors, recombinant thrombomodulin, and direct oral anticoagulants (DOACs) are agents that inhibit serine proteases, and all are effective against DIC. Inhibition of activated coagulation factors by anticoagulants is key to the treatment of DIC. Among them, DOACs can be taken orally and is useful for outpatient treatment. Combination therapy of heparin and nafamostat allows fine-adjustment of anticoagulant and antifibrinolytic effects. While warfarin is an anticoagulant, this agent is ineffective in the treatment of DIC because it inhibits the production of coagulation factors as substrates without inhibiting activated coagulation factors. In addition, monotherapy using tranexamic acid in cases of enhanced-fibrinolytic-type DIC may induce fatal thrombosis. If tranexamic acid is needed for DIC, combination with anticoagulant therapy is of critical importance.

The use of non-vitamin K oral anticoagulants in dialysis patients-A systematic review

Non-vitamin K oral anticoagulants (NOACs) are used for prevention of thromboembolic events, but their use in dialysis patients is debatable. This study investigated the available evidence for the use of NOACs in dialysis patients. Online databases were systematically searched for eligible studies including pharmacokinetic (PK) studies, cohort studies, and randomized control trials (RCTs) comparing NOAC with vitamin K antagonist (VKA) or no anticoagulant treatment. Newcastle Ottawa Scale and Cochrane Risk of bias tool were used for quality assessment. Twenty studies were identified (nine PK studies, two RCTs, and nine cohort studies). Most of the studies investigated apixaban or rivaroxaban. In dialysis patients, less accumulation was reported with apixaban and rivaroxaban compared to dabigatran and edoxaban. PK studies indicate that high dose apixaban or rivaroxaban should be avoided. The two RCTs (rivaroxaban/apixaban vs. VKA) were small and underpowered regarding stroke and bleeding outcomes. Most cohort studies found apixaban superior to VKA, whereas comparison of rivaroxaban with VKA yielded conflicting results. Cohort studies comparing apixaban high dose (5 mg) with low dose (2.5 mg) twice daily suggest a lower risk of stroke with high dose but also a higher risk of bleeding with high dose. Apixaban versus no anticoagulation was compared in one cohort study and did not lower the risk of stroke compared with non-treated regardless of apixaban dosage. Widespread use of NOACs in dialysis patients is limited by adequately sized RCTs. Available evidence suggests a potential for use of apixaban and rivaroxaban in reduced dose.

A Scoping Review of Alternative Anticoagulation Strategies for Hemodialysis Patients with a Mechanical Heart Valve

INTRODUCTION

Patients with end-stage renal disease (ESRD) have high rates of cardiac valvulopathy but can develop contraindications for vitamin K antagonist (VKA) therapy. We explored the evidence for alternative anticoagulation strategies in patients with ESRD with a contraindication for VKA therapy.

METHODS

A scoping review was completed, searching MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Conference abstracts from inception to March 30, 2021. The study population was patients with ESRD who were on VKA therapy and developed a contraindication to VKA therapy use. All data regarding studies, patient characteristics, anticoagulation strategy, and clinical outcomes were summarized.

RESULTS

Twenty-three articles met inclusion criteria. These articles included 57 patients. Contraindications to VKA therapy included calcific uremic arteriolopathy (CUA) (n = 55) and warfarin-induced skin necrosis (n = 2). All studies were either case reports or case series. There were 10 anticoagulation strategies identified. Continuation of VKA therapy was associated with increased death and decreased rates of CUA resolution (80.0% and 10.0%, respectively), compared to apixaban (24.0% and 70.8%), subcutaneous (SC) low-molecular-weight heparin (LMWH) (14.3%, 85.7%), and SC unfractionated heparin (0.0%, 100.0%). While only 5 patient cases were reported with mechanical heart valves, SC LMWH use has been reported in this context with good outcomes.

CONCLUSIONS

In patients with ESRD who develop a contraindication to VKA therapy, several alternative anticoagulation strategies have been reported with superior outcomes to VKA continuation. While outcomes appear superior to continuation of VKA therapy, more data are required before definitive recommendations can be made for the patient with ESRD and a mechanical heart valve.

Safety and Efficacy of Apixaban Use in Peritoneal Dialysis: A Review of the Literature

Objective: To review the safety and efficacy of apixaban for the treatment of nonvalvular atrial fibrillation or venous thromboembolism in patients receiving peritoneal dialysis (PD). Data Sources: A PubMed and MEDLINE search was conducted through December 2020 using the following keywords and Medical Subject Headings (MeSH) terms alone or in various combinations: apixaban, peritoneal dialysis, continuous ambulatory peritoneal dialysis, end-stage renal disease, and hemodialysis. Study Selection and Data Extraction: English-language studies evaluating clinical outcomes pertaining to the use of apixaban in end stage renal disease (ESRD), which included patients receiving peritoneal dialysis were eligible for inclusion. Data Synthesis: Four studies were identified that met inclusion for this review, all retrospective in nature. These studies compared the safety and efficacy of apixaban with standard therapy in ESRD included patients on dialysis, with a very limited number of subjects receiving PD. In these studies, apixaban was shown to be potentially safer and more effective than warfarin. Outcomes did not differentiate between patients receiving PD or not. Conclusions: Use of apixaban in patients receiving PD may be safe and effective based on data from limited patients. Pharmacokinetics and pharmacodynamics of apixaban in the PD setting is an important question that clinicians should consider with use of this medication in the ESRD population. More studies focusing on the PD population are needed to better assess the use of apixaban in this understudied population.

Apixaban vs. Warfarin in Atrial Fibrillation Patients With Chronic Kidney Disease

Background and Objectives: Real-world evidence of apixaban treatment in patients with chronic kidney disease remains scarce. This study aimed to compare the relative risk of stroke or systemic embolism (SE) and major bleeding between apixaban and warfarin in atrial fibrillation (AF) patients with different degrees of kidney function.

Design, Setting, Participants, and Measurements: We evaluated newly diagnosed AF patients between 2004 and 2018, who were receiving apixaban or warfarin. Electronic medical record data were collected from a large healthcare delivery network in Taiwan. The outcomes of hospitalization for stroke/SE and major bleeding were compared with propensity-score matched apixaban and warfarin cohorts. Stratified analyses according to initial apixaban dose (standard dose of 10 mg/day vs. lower dose of 2.5–5.0 mg/day) and baseline estimated glomerular filtration rate were performed.

Results: Each cohort involved 1,625 matched patients. Apixaban was significantly associated with a lower risk of stroke/SE (adjusted hazard ratio [aHR]: 0.74; 95% confidence interval [CI]:0.57–0.97; p = 0.03). The risk of major bleeding was not increased whether in standard doses (aHR: 0.66; 95% CI: 0.45–0.96; p = 0.03) or reduced doses (aHR, 0.84; 95% CI, 0.63–1.12; p = 0.23) of apixaban. Regarding kidney function, apixaban reduced the risk of stroke/SE by 37% in those with an eGFR of <30 ml/min/1.73 m² (aHR: 0.63; 95% CI: 0.40–0.98; p = 0.04).

Conclusions: Compared to warfarin, apixaban is associated with a reduced risk of stroke/SE and is consistent with a subset of AF patients with eGFR <30 ml/min/1.73 m². Both standard and reduced doses of apixaban showed lower risk of major bleeding than those of warfarin.

High-dose versus low-dose iron sucrose in individuals undergoing maintenance haemodialysis: a retrospective study

BACKGROUND

Intravenous iron sucrose is becoming a prevailing treatment for individuals undergoing maintenance haemodialysis, but comparisons of dosing regimens are lacking. The aim of this retrospective review was to evaluate the safety and efficacy of proactively administered high-dose iron sucrose versus reactively administered low-dose iron sucrose in patients undergoing maintenance haemodialysis.

METHODS

We analysed the data of 1500 individuals with maintenance haemodialysis who were treated with either high-dose iron sucrose that was proactively administered (Group HD) or low-dose iron sucrose that was reactively administered (Group LD) at the First Affiliated Hospital of Chongqing Medical University from Jan 1, 2008, to Dec 31, 2020. The primary endpoints were the cumulative doses of iron and erythropoiesis-stimulating agent; the secondary endpoints were the events of nonfatal myocardial infarction, nonfatal stroke, hospitalization for heart failure, infection rate, and death from any cause.

RESULTS

Of the 2124 individuals, 624 individuals were excluded because they met one or more of the exclusion criteria, thus resulting in 1500 individuals who were eligible for inclusion in the study (Group HD, n = 760 and Group LD, n = 740). The median follow-up for the two cohorts was 32 months (range: 25-36). A significant median difference was detected in the monthly iron dose between the groups (1121 mg [range: 800-1274] in the HD group vs. 366 mg [range: 310-690] in the LD group; p < 0.05). The median dose of an erythropoiesis-stimulating agent was 26,323 IU/month (range: 17,596-44,712) in the HD group and 37,934 IU/month (range: 22,402-59,380) in the LD group (median difference: - 7901 IU/month; 95% CI: - 9632--5013; p = 0.000). A significant difference was detected in the secondary endpoints (266 events in 320 cases in the HD group vs. 344 events in 385 cases in the LD group) (HR: 0.62; 95% CI: 0.51-0.79; p < 0.001). A significant difference was not observed in death from any cause (HR: 0.57; 95% CI: 0.48-1.00; p = 0.361).

CONCLUSIONS

For individuals undergoing maintenance haemodialysis, high-dose iron sucrose that was proactively administered may be superior to low-dose iron sucrose that was reactively administered with low doses of erythropoiesis-stimulating agent.

Anticoagulation in patients with kidney failure on dialysis: factor XI as a therapeutic target

Chronic kidney disease is present in almost 10% of the world population and is associated with excess mortality and morbidity. Reduced glomerular filtration rate and the presence and extent of proteinuria, key domains of chronic kidney disease, have both been shown to be strong and independent risk factors for cardiovascular disease. Patients with kidney failure requiring dialysis are at highest risk for cardiovascular events (e.g., stroke or myocardial infarction), and of developing chronic cardiovascular conditions, such as heart failure. Despite the high burden of cardiovascular disease, there is a paucity of evidence supporting therapies to reduce this risk. Although long-term anticoagulant treatment has the potential to prevent thromboembolism in persons with kidney failure on dialysis, this possibility remains understudied. The limited data available on anticoagulation in patients with kidney failure has focused on vitamin K antagonists or direct oral anticoagulants that inhibit thrombin or factor (F) Xa. The risk of bleeding is a major concern with these agents. However, FXI is emerging as a potential safer target for new anticoagulants because FXI plays a greater part in thrombosis than in hemostasis. In this article, we (i) explain the rationale for considering anticoagulation therapy in patients with kidney failure to reduce atherothrombotic events, (ii) highlight the limitations of current anticoagulants in this patient population, (iii) explain the potential benefits of FXI inhibitors, and (iv) summarize ongoing studies investigating FXI inhibition in patients with kidney failure on dialysis.

Atrial fibrillation in advanced renal failure: are there alternative solutions to warfarin-dicumarol?

Patients with atrial fibrillation (AF) and chronic renal failure (CRF) represent a growing population in epidemiological terms since both conditions increase with advancing age. The association of AF and CRF is burdened with a poor prognosis and with a high risk of adverse events, both ischaemic and haemorrhagic. Oral anticoagulant therapy, in these patients, is more problematic, especially due to the concomitant increased risk of bleeding. The use of direct oral anticoagulants (DOACs) in patients with non-severe renal insufficiency appears to be safe and effective. Since all currently available DOACs are at least partially eliminated by the kidney (dabigatran is the direct anticoagulant with the highest rate of renal elimination, approximately 80%), periodic monitoring of renal function is recommended to evaluate possible need for dosage adjustment. In patients with advanced renal insufficiency, the use of DOAC appears controversial, given the small number of clinical studies that have tested its efficacy and safety. It is known, however, that oral anticoagulation therapy with vitamin K antagonists (VKAs) is associated with an increase in nephropathy and renal-vascular calcification. From this point of view, therapy with DOAC could be more advantageous than VKAs. Data from clinical studies would seem to show that the use of dabigatran and rivaroxaban in these patients may lead to a reduction in the inevitable deterioration of renal function.

Low-Molecular-Weight Heparin Anti-Xa Guided Reversal of Apixaban With Prothrombin Complex Concentrate in a Patient on Hemodialysis

The growing use of oral factor Xa (FXa) inhibitors in patients with chronic kidney disease (CKD), particularly the recent increased use of apixaban in patients with end-stage renal disease (ESRD), has created a new dilemma in the already controversial topic of oral FXa inhibitor reversal. With the limited availability of anti-Xa levels specific to oral FXa inhibitors and even scarcer availability of reversal data for patients on these agents with ESRD, ensuring adequate reversal is currently often solely guided by repeat imaging and changes in clinical status. Low molecular weight heparin (LMWH) anti-Xa levels have been used as a more commonly accessible test to guide the need for and efficacy of reversal of oral FXa inhibitors in patients with normal renal function. However, evidence supporting this technique is again lacking in patients with renal dysfunction. This case report focuses on the use of LMWH anti-Xa levels to guide reversal of apixaban in a patient with ESRD on hemodialysis and correlation of those levels to the patient's clinical status.