Nonvitamin K Anticoagulant Agents in Patients With Advanced Chronic Kidney Disease or on Dialysis With AF

Use of DOACs in frail elderly patients in light of class genericization

BACKGROUND

Frailty and comorbidity influence the therapeutic approach in everyday clinical practice. The DOACs genericization opens a reflection on their differences from a pharmacological and bioavailability point of view, particularly in elderly frail patients. The aim of this project was to create a national Delphi consensus on the topic of the use of DOACs for atrial fibrillation (AF) in such patients, in light of the genericization of the class.

METHODS AND RESULTS

The consensus dealt with 3 main topics: a) efficacy and safety of DOACs in elderly and/or frail patients; b) therapeutic choice in specific frailty scenarios; c) DOACs genericization. 56 cardiologists, two internists and two neurologists from Italy expressed their level of agreement on each statement by using a 5-point Likert scale (1: strongly disagree, 2: disagree, 3: uncertain, 4: agree, 5: strongly agree). A positive consensus was reached if the percentage of agreement (vote 1-2, positive consensus) or disagreement (votes 4-5, negative consensus) was >66%; otherwise, no consensus was reached. Results are displayed accordingly.

CONCLUSIONS

After 10 years of everyday clinical management of DOACs for AF, specific elements differentiating a molecule from another, either for efficacy or for safety, are consolidated. However, some uncertainties still exist in particular contexts, such as chronic kidney disease or cancer patients. Clinicians have an unsure attitude towards generic drugs, because clinical practice is lacking as well as a proper knowledge of the topic. Albeit being an alternative, the choice of the generic drug must remain the responsibility of the clinician.

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.

Selection criteria for anticoagulants: survey of Japanese cardiologists based on their daily clinical practice: the Selection DOAC study

BACKGROUND

In patients with atrial fibrillation (AF), direct oral anticoagulants (DOACs) have been utilized as an alternative to warfarin, which is known to have several limitations. This study aimed to clarify the selection criteria for anticoagulants, considering both individual patient factors and the differences between various drugs.

METHODS

This study conducted a web-based questionnaire from September 20, 2023 to October 3, 2023, among physicians who were members of a cardiology-specific website.

RESULTS

In total, 172 respondents were enrolled in this study. Edoxaban was the most frequently selected anticoagulant (39.1%), followed by apixaban (32.7%) and rivaroxaban (16.8%). Logistic regression analysis revealed that increased concern for adherence enhanced the frequency of selecting edoxaban (odds ratio [OR] = 2.42; p = 0.047), with the opposite trend observed for dabigatran (OR = 0.404; p = 0.029). The selection of apixaban is related to whether the patient is able to maintain a regular lifestyle, including adherence to medication schedules (OR = 1.874; p = 0.031). Furthermore, detailing activities from a medical representative, especially regarding a new indication, were found to influence drug selection for rivaroxaban (OR = 2.422; p = 0.047).

CONCLUSION

This study revealed that edoxaban is the most frequently selected anticoagulant. Although prescribing cardiologists select drugs based on background factors, adherence to medication and information from medical representatives were also crucial factors in the selection process.

Efficacy and safety of oral anticoagulants according to kidney function among patients with atrial fibrillation

BACKGROUND AND AIMS

Patients with severely reduced kidney function have been excluded from randomized controlled trials and data on the safety and efficacy of direct oral anticoagulants (DOACs) according to kidney function remain sparse. The aim was to evaluate the safety and efficacy of the DOACs across subgroups of kidney function.

METHODS

Using multiple Danish nationwide registers and laboratory databases, we included patients initiated on oral anticoagulants (OACs) with atrial fibrillation and available creatinine level and followed patients for 2 years to evaluate occurrence of stroke/thromboembolism (TE) and major bleeding.

RESULTS

Among 26 686 included patients, 3667 (13.7%) had an estimated glomerular filtration rate (eGFR) of 30-49 mL/min/1.73 m2 and 596 (2.2%) had an eGFR below 30 mL/min/1.73 m2. We found no evidence of differences regarding the risk of stroke/TE between the OACs (P-value interaction >0.05 for all). Apixaban was associated with a lower 2-year risk of major bleeding compared to vitamin K antagonists (VKA) [hazard ratio 0.79, 95% confidence interval (CI) 0.67-0.93], and the risk difference was significantly larger among patients with reduced kidney function (P-value interaction 0.018). Rivaroxaban was associated with a higher risk of bleeding compared to apixaban (hazard ratio 1.78, 95%CI 1.32-2.39) among patients with eGFR 30-49 mL/min/1.73 m2.

CONCLUSIONS

Overall, we found no differences regarding the risk of stroke/TE, but apixaban was associated with a 21% lower relative risk of major bleeding compared to VKA. This risk reduction was even greater when comparing apixaban to VKA among patients with eGFR 15-30 mL/min/1.73 m2, and when comparing apixaban to dabigatran and rivaroxaban among patients with eGFR 30-49 mL/min/1.73 m2.

The Safety and Effectiveness of Apixaban in Patients with End-Stage Kidney Disease on Dialysis: A Retrospective Observational Study

Background: Apixaban has been increasingly utilized for various FDA-approved indications, including stroke prevention and venous thromboembolism (VTE) treatment in patients with end stage kidney disease (ESKD) on hemodialysis. However, the safety and efficacy of its use in this population is not well established. Hence, the purpose of this study is to evaluate the safety and effectiveness of apixaban by examining outcomes in this population. Methods: This was a retrospective observational study that involved adults with ESKD who were on hemodialysis and prescribed apixaban from our hospital's outpatient pharmacy between 1 May 2015, and 31 March 2022. Demographics, apixaban indications, dose appropriateness, concomitant antiplatelet use, and comorbidities data were collected. Bleeding and thromboembolic events were also collected. Results: Sixty-six patients fulfilled the inclusion criteria, 50% of them males. Median age was 71 (63.5-82) years, and the median BMI 28.2 (59.5-86.25) kg/m2. The median follow-up time was 5 (1.9-12.3) months. Concomitant antiplatelet use (39.4%) and high medication adherence (84.8%) were observed. During follow-up, major bleeding events occurred in 15.2% of cases, with minor bleeding being more common (36.4%), and VTE and stroke events occurred in 4.5% of cases; appropriate dosing was prevalent (62.1%), and there was an overall all-cause mortality rate of 34.8%. Most patients received a 2.5 mg BID apixaban dose (56.1%), including both NVAF and VTE groups. Notably, the multivariate logistic regression analysis indicated that weight, and daily dose were insignificant predictors of bleeding events (p = 0.104, 0.591), however, the BMI was the main independent risk factor for bleeding in this population [OR = 0.9, 95% CI: 0.8-0.99; p = 0.023]. Conclusions: Our analysis of apixaban-treated ESKD patients highlights that the risk of bleeding is significant, and BMI was the main independent risk factor. A larger prospective study is needed to confirm our findings.

Cardiovascular and renal outcomes in patients with atrial fibrillation and stage 4-5 chronic kidney disease receiving direct oral anticoagulants: a multicenter retrospective cohort study

The role of direct oral anticoagulants (DOAC) in patients with atrial fibrillation (AF) and stage 4-5 chronic kidney disease (CKD) is controversial. Electronic medical records from 2012 to 2021 were retrieved for patients with AF and stage 4-5 CKD receiving oral anticoagulants. Patients were separated into those receiving DOACs (dabigatran, rivaroxaban, apixaban, or edoxaban) or vitamin K antagonists (VKA). Primary outcomes included ischemic stroke (IS), systemic thrombosis (SE), major bleeding, gastrointestinal bleeding, hemorrhagic stroke, acute myocardial infarction, cardiovascular death, and all-cause death. Renal outcomes included eGFR declines, creatinine doubling, progression to dialysis, and major adverse kidney events (MAKE). The primary analysis was until the end of follow up and the results at 1-year and 2-year of follow ups were also assessed. 2,382 patients (DOAC = 1,047, VKA = 1,335) between 2012 and 2021 with AF and stage 4-5 CKD were identified. The mean follow-up period was 2.3 ± 2.1 years in DOCAs and 2.6 ± 2.3 years in VKA respectively. At the end of follow up, the DOAC patients had significantly decreased SE (subdistribution hazard ratio [SHR] = 0.50, 95% confidence interval [CI] = 0.34-0.73), composite of IS/SE (SHR = 0.78, 95% CI = 0.62-0.98), major bleeding (HR = 0.77, 95% CI = 0.66-0.90), hemorrhagic stroke (HR = 0.52, 95% CI = 0.36-0.76), and composite of bleeding events (SHR = 0.80, 95% CI = 0.69-0.92) compared with VKA patients. The IS efficacy outcome revealed neutral between DOAC and VKA patients (HR = 1.05, 95% CI = 0.79-1.39). In addition, DOAC patients had significantly decreased rates of eGFR decline > 50% (SHR = 0.75, 95% CI = 0.64-0.87), creatinine doubling (SHR = 0.80, 95% CI = 0.67-0.95), and MAKE (SHR = 0.81, 95% CI = 0.71-0.93). In patients with AF and stage 4-5 CKD, use of DOAC was associated with decreased rates of a composite of ischemic stroke/systemic embolism, a composite of bleeding events, and renal events compared to VKA. Efficacy and safety benefits associated with apixaban at standard doses were consistent throughout follow-up.

Supplementation with Ashitaba (Angelica keiskei) Yellow Stem Exudate Prevents Aging-Induced Thrombotic Tendencies and Systemic Inflammation Without Affecting Body Weight Gain in Mice

Angelica keiskei Koidzumi (Ashitaba) is a traditional folk medicine and health supplement in Japan. Ashitaba yellow stem exudate (AYE) contains abundant chalcones and thus has the potential to treat and prevent many pathological states such as cancer, inflammation, obesity, diabetics, thrombosis, and hypertension. Levels of plasminogen activator inhibitor 1 (PAI-1), a key regulator of the fibrinolytic system, increase with age in mouse plasma. Therefore, we aimed to determine the effects of AYE on plasma thrombotic parameters in aging mice. Long-term (52 weeks) AYE supplementation significantly decreased age-induced increases of PAI-1 in mouse plasma. Supplementation with AYE decreased levels of the acute-phase and fibrinolytic protein plasma plasminogen, and significantly decreased those of tumor necrosis factor α. These results suggested that continuous intake of AYE throughout life decreases age-induced systemic inflammation and prevents thrombotic tendencies without affecting body weight gain in aged mice. Our findings showed that supplementing diets with AYE might help to prevent thrombotic diseases in elderly individuals.

Use of direct oral anticoagulants for venous thromboembolism treatment at extremes of body weight, renal and liver function: an illustrated review

Direct oral anticoagulants (DOACs) have been a welcome addition to clinical practice due to the practical advantages they confer over traditional anticoagulants. In many countries, DOACs are now used as first-line treatment for the management of venous thromboembolism (VTE). Traditional anticoagulants allow for a degree of individualization, either through monitoring the international normalized ratio in the case of vitamin-K antagonists or through dose titration according to bodyweight in the case of low-molecular-weight heparin. However, the use of fixed doses and removal of the need for routine monitoring has created uncertainty in prescribing DOACs for patients at the extremes of bodyweight, renal function, and patients with liver impairment, who were not well represented in the DOAC licensing clinical trials. The discipline of pharmacokinetics is concerned with the movement of drugs through the body. Although the extremes of bodyweight and renal and liver function will influence the pharmacokinetics of DOACs, are these changes significant enough to affect clinical outcomes of bleeding and thrombosis? In other words, can the fixed-dosing strategy of DOACs accommodate these differences in physiology? In this review, we recap key pharmacokinetic principles for drug dosing; review venous thromboembolism trial and real-world data on patients prescribed DOACs at the extremes of bodyweight, renal function, and liver function; relate this to the pharmacokinetic properties of DOACs; and summarize the state of the field and current unknowns.

Left Atrial Appendage Occlusion versus Novel Oral Anticoagulation for Stroke Prevention in Atrial Fibrillation-One-Year Survival

Aim To compare the 1-year survival rate of patients with atrial fibrillation (AF) following left atrial appendage occluder (LAAO) implantation vs. treatment with novel oral anticoagulants (NOACs).

METHODS

We have conducted an indirect, retrospective comparison between LAAO and NOAC registries. The LAAO registry is a national prospective cohort of 419 AF patients who underwent percutaneous LAAO between January 2008 and October 2015. The NOACs registry is a multicenter prospective cohort of 3138 AF patients treated with NOACs between November 2015 and August 2018. Baseline patient characteristics were retrospectively collected from coded diagnoses of hospitalization and outpatient clinic notes. Follow-up data was sorted from coded diagnoses and the national civil registry. Subjects were matched according to propensity score. Baseline characteristics were compared using Chi-Square and student's t-test. Survival analysis was performed using Kaplan-Meier survival curves, log-rank test, and multivariable Cox regression, adjusting for possible confounding variables.

RESULTS

This study included 114 subjects who underwent LAAO implantation and 342 subjects treated with NOACs. The mean age of participants was 77.9 ± 7.44 and 77.1 ± 11.2 years in the LAAO and NOAC groups, respectively (p = 0.4). The LAAO group had 70 (61%) men compared to 202 (59%) men in the NOAC group (p = 0.74). No significant differences were found in baseline comorbidities, renal function, or CHA2DS2-VASc score. One-year mortality was observed in 5 (4%) patients and 32 (9%) patients of the LAAO and NOAC groups, respectively. After adjusting for confounders, LAAO was significantly associated with a lower risk for 1-year mortality (HR 0.38, 95%CI 0.14-0.99). In patients with impaired renal function, this difference was even more prominent (HR 0.21 for creatinine clearance (CrCl) < 60 mL/min).

CONCLUSIONS

In a pooled analysis of two registries, we found a significantly lower risk for 1-year mortality in patients with AF who were implanted with LAAO than those treated with NOACs. This finding was more prominent in patients with impaired renal function. Future prospective direct studies should further investigate the efficacy and adverse effects of both treatment strategies.

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.

Percutaneous Left Atrial Appendage Closure Among Patients With Diabetes (Insights from a National Database)

Atrial fibrillation is a major risk factor for stroke. Left atrial appendage closure (LAAC) has emerged as an alternative to anticoagulation for patients with high risk of bleeding. Diabetes mellitus (DM) is associated with adverse events after cardiac procedures. We sought to compare procedural and hospital outcomes in patients who underwent LAAC with and without DM. The Nationwide Inpatient Database was queried for patients with atrial fibrillation who underwent LAAC between January 1, 2016, and December 31, 2019. The primary outcome was all adverse events that included in-hospital death, acute myocardial infarction, cardiac arrest, stroke, pericardial effusion, pericardial tamponade, pericardiocentesis, pericardial window, and postprocedural hemorrhage requiring blood transfusion. Analysis included 62,220 patients who underwent LAAC from 2016 to 2019; 34.9% of patients had DM. There was a slight increase in the percentage of patients who underwent LAAC who had DM during the study period, from 29.92% to 34.93%. In unadjusted and adjusted analysis, there was no significant difference in all adverse events between patients with and without DM who underwent LAAC (9.18% vs 8.77%, respectively, adjusted p = 0.63), and no difference in length of stay. Patients with DM have higher risk of acute kidney injury (3.75 vs 1.96%, p <0.001). This nationwide retrospective study demonstrates that DM is not associated with an increase in adverse event rates in patients who underwent LAAC.

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.

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.

Retrospective Comparison of Patients ≥ 80 Years With Atrial Fibrillation Prescribed Either an FDA-Approved Reduced or Full Dose Direct-Acting Oral Anticoagulant

Direct-acting oral anticoagulants (DOACs) represent the standard for preventing stroke and systemic embolization (SSE) in patients with atrial fibrillation (AF). There is limited information for patients ≥ 80 years. We report a retrospective analysis of AF patients ≥ 80 years prescribed either a US Food and Drug Administration (FDA)-approved reduced (n = 514) or full dose (n = 199) DOAC (Dabigatran, Rivaroxaban, or Apixaban) between January 1st, 2011 (first DOAC commercially available) and May 31st, 2017. The following multivariable differences in baseline characteristics were identified: patients prescribed a reduced dose DOAC were older (p < 0.001), had worse renal function (p = 0.001), were more often prescribed aspirin (p = 0.004) or aspirin and clopidogrel (p < 0.001), and more often had new-onset AF (p = 0.001). SSE and central nervous system (CNS) bleed rates were low and not different (1.02 vs 0 %/yr and 1.45 vs 0.44 %/yr) for the reduced and full dose groups, respectively. For non-CNS bleeds, rates were 10.89 vs 4.15 %/yr (p < 0.001, univariable) for the reduced and full doses, respectively. The mortality rate was 6.24 vs 1.75 %/yr (p = 0.001, univariable) for the reduced and full doses. Unlike the non-CNS bleed rate, mortality rate differences remained significant when adjusted for baseline characteristics. Thus, DOACs in patients ≥ 80 with AF effectively reduce SSE with a low risk of CNS bleeding, independent of DOAC dose. The higher non-CNS bleed rate and not the mortality rate is explained by the higher risk baseline characteristics in the reduced DOAC dose group. Further investigation of the etiology of non-CNS bleeds and mortality is warranted.

A systematic review of the efficacy and safety of anticoagulants in advanced chronic kidney disease

BACKGROUND

Patients with chronic kidney disease (CKD) have an increased risk of venous thromboembolism (VTE) and atrial fibrillation (AF). Anticoagulants have not been studied in randomised controlled trials with CrCl < 30 ml/min. The objective of this review was to identify the impact of different anticoagulant strategies in patients with advanced CKD including dialysis.

METHODS

We conducted a systematic review of randomized controlled trials and cohort studies, searching electronic databases from 1946 to 2022. Studies that evaluated both thrombotic and bleeding outcomes with anticoagulant use in CrCl < 50 ml/min were included.

RESULTS

Our initial search yielded 14,503 papers with 53 suitable for inclusion. RCTs comparing direct oral anticoagulants (DOACs) versus warfarin for patients with VTE and CrCl 30-50 ml/min found no difference in recurrent VTE events (RR 0.68(95% CI 0.42-1.11)) with reduced bleeding (RR 0.65 (95% CI 0.45-0.94)). Observational data in haemodialysis suggest lower risk of recurrent VTE and major bleeding with apixaban versus warfarin. Very few studies examining outcomes were available for therapeutic and prophylactic dose low molecular weight heparin for CrCl < 30 ml/min. Findings for patients with AF on dialysis were that warfarin or DOACs had a similar or higher risk of stroke compared to no anticoagulation. For patients with AF and CrCl < 30 ml/min not on dialysis, anticoagulation should be considered on an individual basis, with limited studies suggesting DOACs may have a preferable safety profile.

CONCLUSION

Further studies are still required, some ongoing, in patients with advanced CKD (CrCl < 30 ml/min) to identify the safest and most effective treatment options for VTE and AF.

Nonvalvular atrial fibrillation in patients undergoing chronic hemodialysis. Should dialysis patients with atrial fibrillation receive oral anticoagulation?

Chronic kidney disease (CKD) is an independent risk factor for presenting atrial fibrillation (AF), which conditions an increased risk already present in CKD of suffering a thromboembolic event. And this risk is even higher in the hemodialysis (HD) population. On the other hand, in CKD patients and even more so in HD patients, the probability of suffering serious bleeding is also higher. Therefore, there is no consensus on whether or not to anticoagulate this population. Taking as a model what is advised for the general population, the most common attitude among nephrologists has been to opt for anticoagulation, even though there is no randomized studies to support it. Classically, anticoagulation has been done with vitamin K antagonists, at high cost for our patients: severe bleeding events, vascular calcification, and progression of nephropathy, among other complications. With the emergence of direct-acting anticoagulants, a hopeful outlook was opened in the field of anticoagulation, as they were postulated as more effective and safer drugs than antivitamin K. However, in clinical practice, this has not been the case. In this paper we review various aspects of AF and its anticoagulant treatment in the HD population.

The Risk of Major Bleeding With Apixaban Administration in Patients With Acute Kidney Injury

BACKGROUND

Apixaban is eliminated by the kidneys and in acute kidney injury (AKI) there is potential for an increase in apixaban exposure and bleeding events. In one instance, data have shown higher than normal bleed risk in patients with AKI, unless calibrated anti-factor Xa monitoring is used, which is not widely available.

OBJECTIVE

To evaluate bleeding with apixaban administration to hospitalized patients with an AKI in an unmonitored real-world scenario.

METHODS

We conducted a retrospective study of patients admitted to a large urban academic teaching hospital from April 2015 to March 2022, who received apixaban for venous thromboembolism or nonvalvular atrial fibrillation (NVAF). The primary outcome evaluated major bleeding when apixaban was administered to patients with or without an AKI.

RESULTS

A total of 232 patients were evaluated (116 per group). Most patients (79.7%) were on apixaban for NVAF, 32.7% had chronic kidney disease, 58.2% were on a medication increasing bleed risk, and HAS-BLED score was a median of 2 in both groups. No differences were noted between groups for bleeding (AKI group 7.8% vs non-AKI 3.4%; P = 0.15), and on regression analysis, coadministration of a P2Y12 inhibitor was predictive of major bleeding (odds ratio = 5.9; 95% confidence interval = 1.4-23.6).

CONCLUSION AND RELEVANCE

Although no differences between groups were noted, apixaban use in the AKI group resulted in a higher than normally reported incidence of apixaban-associated major bleeding, and concomitant antiplatelet use increased bleed risk as well. Cautious use of apixaban and further investigation with larger studies are warranted in this area.

Safety of Non-Vitamin K Antagonist Oral Anticoagulant Treatment in Patients with Chronic Kidney Disease and Kidney Transplant Recipients

The use of novel oral anticoagulants in patients with impaired renal function or undergoing immunosuppressive therapy is limited due to the risk of drug-to-drug interactions and anticoagulation-related adverse events. This article aims to assess the current data on the safety of direct-acting oral anticoagulant-based therapy in the population of kidney transplant recipients and patients with impaired renal function. The most important factors affecting the safety of treatment are the incidence of bleeding events, thromboembolic events, deaths and drug-to-drug interactions. The available data were compared to the findings on warfarin-based anticoagulation. Findings on the use of novel oral anticoagulants in kidney transplant recipients are limited yet promising in terms of safety and efficacy of use. However, current recommendations state that the co-administration of non-vitamin K antagonist oral anticoagulants with several immunosuppressive agents is contraindicated.

Direct Oral Anticoagulants vs. Warfarin in Hemodialysis Patients With Atrial Fibrillation: A Systematic Review and Meta-Analysis

Background

The use of Direct Oral Anticoagulants (DOACs) in patients who have both atrial fibrillation (AF) and end-stage renal disease (ESRD) requiring hemodialysis remains controversial, with warfarin remaining the mainstay of the treatment. As hemodialysis patients were excluded from most clinical DOACs trials, the evidence of their efficacy and safety is lacking in this cohort of patients.

Aim

To review the current evidence investigating safety profile and the efficacy of DOACs in comparison with warfarin in patients with AF and end-stage renal disease (ESRD) requiring hemodialysis.

Methods and Results

We included five studies with a total of 34,516 patients in our meta-analysis. The outcomes were major bleeding, ischemic stroke, systemic embolization, hemorrhagic stroke, gastrointestinal bleeding, minor bleeding, and death. Of these patients, 31,472 (92.14%) received warfarin and 3,044 patients received DOACs (8.91%). No significant differences in the incidence of hemorrhagic stroke, major bleeding, hemodialysis access site bleeding, ischemic stroke, and GI bleeding were found between DOACs and warfarin. However, there were higher rates of systemic embolization, minor bleeding, and death events in patients who received DOACs than in the warfarin group (3.39% vs. 1.97%, P-value = 0.02), (6.78% vs. 2.2%, P-value 0.02), and (11.38% vs. 5.12%, P-value < 0.006) respectively.

Conclusion

In patients on dialysis who require anticoagulation for AF, warfarin could be associated with a significant reduction in minor bleeding, systemic embolization, and death compared to DOACs. These findings need to be validated by further prospective studies to address the best strategy to deal with the increased thrombotic and bleeding risks in such patients.

Eight-Year Trends in Direct-Acting Oral Anticoagulant Dosing, Based on Age and Kidney Function, in Patients With Atrial Fibrillation

OBJECTIVE

Concerns have been raised over the appropriateness of dosing of direct-acting oral anticoagulants (DOACs) in clinical practice. We investigated this issue in patients who were initiated on a DOAC in Australian general practices.

METHODS

This was a retrospective study among patients newly diagnosed with atrial fibrillation (AF) who were prescribed DOACs, using data obtained from 417 general practice sites across Australia over 8 years (2011-2019). Direct-acting oral anticoagulant dosing was compared with published recommendations, in relation to age and kidney function.

RESULTS

A total of 11,251 patients (mean age, 72.8 y; 46.8% female) newly diagnosed with AF were prescribed a DOAC. Of these, 2667 patients (23.7%) had a recorded prescription of a potentially inappropriate DOAC dosage, of whom 2304 (86.4%) and 283 (10.6%) were prescribed lower and higher than the recommended dosage, respectively. The remaining 80 patients (3.0%) were initiated on DOACs when contraindicated based on renal function. Overall, the proportion of patients who seemed to be initiated on a potentially inappropriate DOAC dose decreased from 38.3% (95% confidence interval, 26.1%-51.8%) in 2012 to 22.7% (95% confidence interval, 19.8%-26.0%; P < 0.001) in 2019. By 2019, 19.4%, 20.3%, and 9.3% of the patients with a recorded prescription of apixaban, rivaroxaban, and dabigatran, respectively, received a lower-than-guideline-recommended dose. The patients were more likely to be prescribed a potentially inappropriate dosage if they were elderly with multiple comorbidities.

CONCLUSIONS

Potential inappropriate DOAC dosing is a problem in the prevention of stroke associated with AF. Nearly 1 in 5 patients received a lower-than-guideline-recommended dose, indicating a need for strategies to raise awareness among prescribers.

Plasma Rivaroxaban Level in Patients With Early Stages of Chronic Kidney Disease-Relationships With Renal Function and Clinical Events

Introduction Drug accumulation of rivaroxaban is a concern in patients with chronic kidney disease (CKD). Data regarding the plasma rivaroxaban levels in early CKD patients and its relationship with clinical events is lacking. Methods Early CKD patients (Stage 1-3) with atrial fibrillation who received rivaroxaban (15 or 20 mg daily) were recruited. Plasma rivaroxaban levels were measured at 2 hours (peak) and 24 hours (trough) after drug administration, and correlated with eGFR and clinically significant events during the follow-up period (1 January 2018 to 31 October 2021). Results Ninety-two patients were included (CKD stage 1 n=10, stage 2 n=53, stage 3 n=29). Plasma trough levels in patients with stage 3 CKD were significantly higher than those with stage 2 and 1 CKD (66.0±34.9 ng/ml vs. 35.7 ± 24.7 ng/ml vs. 34.7 ± 26.2 ng/ml, respectively, p=0.005), and showed inverse relationship with eGFR (r=0.391, p=0.001) in patients receiving 20 mg daily. The plasma trough rivaroxaban level correlated with PT and APTT (r = 0.650 and 0.44, respectively, p<0.001 for both). Plasma trough rivaroxaban level in those with bleeding were higher than those who did not (59.9 ± 35.6 ng/ml vs. 41.1 ± 29.2 ng/ml, p=0.011), and multivariate analysis suggested that plasma trough rivaroxaban level was associated with the rate of bleeding complications (OR: 1.020, 95% CI 1.002-1.038, p=0.028). Conclusion Plasma trough rivaroxaban levels correlated with renal function in early CKD patients, and its measurement may help dosage optimization in patients with renal impairment. Moreover, our data suggests that there may be an association between plasma trough rivaroxaban level and the rate of bleeding complication.

Potential drug-drug interaction between tolvaptan and warfarin in a geriatric patient with heart failure

Tolvaptan is a key drug for patients with heart failure. Here, we present a 92-year-old woman, whose PT-INR/dose increased from 1.74 to 3.30 after warfarin and tolvaptan co-administration, and resulted in a large cerebral infarction after warfarin dose down. Therefore, the interaction between these two drugs may be clinically significant.

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.

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.

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.

Practical Considerations for Use of Direct Oral Anticoagulants in Children

Direct oral anticoagulants (DOACs) provide an attractive alternative for the management and prevention of thrombosis in pediatric patients. With multiple ongoing and published pediatric trials and recent regulatory approval of dabigatran and rivaroxaban, the landscape of pediatric anticoagulation is rapidly changing. However, as pediatricians gain experience with these drugs, it is important to be mindful of pediatric-specific considerations that may limit the use of DOACs in certain children and adolescents. While there is increasing adult data and experience, there is a paucity of real-world evidence to guide the use of these drugs in children who would not have met clinical trial inclusion criteria. In this mini review, we summarize pediatric specific data, areas for future research, and practical considerations for the use of DOACs in children and adolescents.

Starting dose and dose adjustment of non-vitamin K antagonist oral anticoagulation agents in a nationwide cohort of patients with atrial fibrillation

This study aims to provide real-world data about starting-dose of NOACs and dose-adjustment in patients with atrial fibrillation (AF). In fact, even if new oral anticoagulation agents (NOACs) have a predictable effect without need for regular monitoring, dose-adjustments should be performed according to the summary of product information and international guidelines. We employed the Italian Medicines Agency monitoring registries comprising data on a nationwide cohort of patients with AF treated with NOACs from 2013 to 2018. Logistic regression analysis was used to evaluate the determinants of dosage choice. During the reference period, treatment was commenced for 866,539 patients. Forty-five percent of the first prescriptions were dispensed at a reduced dose (dabigatran 60.3%, edoxaban 45.2%, apixaban 40.9%, rivaroxaban 37.4%). The prescription of reduced dose was associated with older age, renal disease, bleeding risk and the concomitant use of drugs predisposing to bleeding, but not with CHA₂DS₂-VASc and HAS-BLED. A relative reduction of the proportion of patients treated with low dosages was evident overtime for dabigatran and rivaroxaban; whereas prescription of low dose apixaban and edoxaban increased progressively among elderly patients. Evidence based on real-world data shows a high frequency of low dose prescriptions of NOACs in AF patients. Except for older age, renal disease, bleeding risk and the concomitant use of drugs predisposing to bleeding, other factors that may determine the choice of reduced dose could not be ascertained. There may be potential under-treatment of AF patients, but further evaluation is warranted.

[Use of antiplatelet therapy and direct oral anticoagulants in candidates for renal transplantation: The French guidelines from the CTAFU]

OBJECTIVE

To define guidelines for the use of antiplatelet therapy (AT) and direct oral anticoagulants (DOAC) in candidates for kidney allotransplantation.

METHOD

A review of the medical literature following a systematic approach was conducted by the CTAFU to report the use of AT and DOAC before major surgery and in the setting of advanced chronic kidney disease, defining their managment prior to kidney transplantation with the corresponding level of evidence.

RESULTS

DOAC are not recommended in patients under dialysis. Aspirin therapy, but not anti-P2Y₁₂ and DOAC, may be maintained during renal transplantation. Anti-P2Y₁₂ and DOAC should not be use in patients awaiting a kidney transplant, except when a living donor is scheduled, therefore authorizing treatment interruption in optimal conditions. Further data regarding DOAC reversion and monitoring may improve their use in this setting. Global level of evidence is weak.

CONCLUSION

These French recommendations should contribute to improve surgical management of kidney transplant candidates exposed to AT or DOA.

Relation of apixaban bleeding rates to dose in patients with chronic kidney disease

The objective of this study was to evaluate the safety and efficacy of apixaban 5 mg twice daily vs 2.5 mg twice daily for nonvalvular atrial fibrillation or venous thromboembolism in patients with chronic kidney disease stage 4 and 5, including those on hemodialysis. Data were collected retrospectively on patients with advanced chronic kidney disease and nonvalvular atrial fibrillation and/or venous thromboembolism who received apixaban while hospitalized at our institution between January 2013 and August 2018. The 5 mg twice daily group included 22 patients, and the 2.5 mg twice daily group included 73 patients. There was no difference between groups in major bleeding events (9.1% vs. 12.3%, P = 1.00), any bleeding event (45.4% vs. 67.1%, P = 0.08), ischemic stroke (0% vs. 2.7%, P = 1.00), or venous thromboembolism (4.5% vs. 0%, P = 0.23). Subgroup analyses of patients with a serum creatinine >2.5 mg/dL or creatinine clearance <25 mL/min and patients on hemodialysis produced similar results. Until larger trials are conducted, clinicians should make patient-specific decisions about the optimal dose of apixaban in patients with severe renal impairment.

Oral Anticoagulation Therapy for Venous Thromboembolism in Norway: Time Trends and Treatment Patterns

PURPOSE

Data describing treatment patterns of patients with venous thromboembolism (VTE) patients in Scandinavia are scarce. This study sought to address this scarcity by describing demographic and clinical characteristics, trends in the use of oral anticoagulants (OACs), and treatment patterns in patients treated for VTE in Norway between 2013 and 2017.

METHODS

Using data from Norway's nationwide registries, a cohort study included patients newly (after 2008) treated OACs who were diagnosed with VTE between January 2013 and December 2017 and were dispensed an OAC (warfarin, apixaban, rivaroxaban, dabigatran, or edoxaban) within 30 days. Patient characteristics and the percentage of patients with VTE who initiated treatment with each OAC for each calendar year were reported. Initial therapy persistence was assessed using Kaplan-Meier curves and compared between the OAC groups using the log-rank test.

FINDINGS

The comorbidity burden was similar between patients taking warfarin and those taking apixaban but lower among patients taking rivaroxaban. Direct oral anticoagulant (DOAC) use increased from 33.2% to 93.6% during the study period, whereas warfarin use decreased. Persistence was higher in the apixaban cohort compared with the warfarin cohort, with the difference mostly apparent after 6 months, whereas persistence was similar between the patients taking rivaroxaban and those taking warfarin.

IMPLICATIONS

Between 2013 and 2017, DOAC use among patients with VTEs increased markedly in Norway, whereas the use of warfarin decreased. Patients taking apixaban had higher persistence compared with those taking warfarin, whereas patients taking warfarin and those taking rivaroxaban had similar persistence. Further studies with longer follow-up are required to examine the use of extended OAC treatment for VTE.

The cardiovascular-dialysis nexus: the transition to dialysis is a treacherous time for the heart

Chronic kidney disease (CKD) patients require dialysis to manage the progressive complications of uraemia. Yet, many physicians and patients do not recognize that dialysis initiation, although often necessary, subjects patients to substantial risk for cardiovascular (CV) death. While most recognize CV mortality risk approximately doubles with CKD the new data presented here show that this risk spikes to >20 times higher than the US population average at the initiation of chronic renal replacement therapy, and this elevated CV risk continues through the first 4 months of dialysis. Moreover, this peak reflects how dialysis itself changes the pathophysiology of CV disease and transforms its presentation, progression, and prognosis. This article reviews how dialysis initiation modifies the interpretation of circulating biomarkers, alters the accuracy of CV imaging, and worsens prognosis. We advocate a multidisciplinary approach and outline the issues practitioners should consider to optimize CV care for this unique and vulnerable population during a perilous passage.

2021 Update of the International Council for Standardization in Haematology Recommendations for Laboratory Measurement of Direct Oral Anticoagulants

In 2018, the International Council for Standardization in Haematology (ICSH) published a consensus document providing guidance for laboratories on measuring direct oral anticoagulants (DOACs). Since that publication, several significant changes related to DOACs have occurred, including the approval of a new DOAC by the Food and Drug Administration, betrixaban, and a specific DOAC reversal agent intended for use when the reversal of anticoagulation with apixaban or rivaroxaban is needed due to life-threatening or uncontrolled bleeding, andexanet alfa. In addition, this ICSH Working Party recognized areas where additional information was warranted, including patient population considerations and updates in point-of-care testing. The information in this manuscript supplements our previous ICSH DOAC laboratory guidance document. The recommendations provided are based on (1) information from peer-reviewed publications about laboratory measurement of DOACs, (2) contributing author's personal experience/expert opinion and (3) good laboratory practice.

Clinical Evidence for the Choice of the Direct Oral Anticoagulant in Patients with Atrial Fibrillation According to Creatinine Clearance

Atrial fibrillation (AF) often coexists with chronic kidney disease (CKD), which confer to the patient a higher risk of both thromboembolic and hemorrhagic events. Oral anticoagulation therapy, nowadays preferably with direct oral anticoagulants (DOACs), represents the cornerstone for ischemic stroke prevention in high-risk patients. However, all four available DOACs (dabigatran, apixaban, rivaroxaban and edoxaban) are eliminated by the kidneys to some extent. Reduced kidney function facilitates DOACs accumulation and, therefore, different dose reductions are required, with slight differences between American and European recommendations especially in case of severe renal impairment (creatinine clearance < 30 mL/min). Overall, the use of DOACs in patients with non-end stage CKD and AF is effective similarly to warfarin, showing a better safety profile. The management of thromboembolic risk among patients with AF on dialysis remains challenging, as warfarin effectiveness for stroke prevention in this population is questionable and retrospective data on apixaban need to be confirmed on a larger scale. In kidney transplant recipients, DOACs may provide a potentially safer option compared to warfarin, but co-administration with immunosuppressants is a matter of concern.

Efficacy and Safety of Direct Oral Anticoagulants vs Warfarin in Patients with Chronic Kidney Disease and Dialysis Patients: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE: Systematic reviews and meta-analyses of direct oral anticoagulants (DOACs) for patients with chronic kidney disease (CKD) or dialysis patients are lacking. We aimed to compare the efficacy and safety of DOACs and warfarin in patients with CKD requiring anticoagulation therapy.

METHODS

We performed a systematic review and meta-analysis of six randomized controlled trials and 19 observational studies, with the inclusion criteria being a comparative study between DOACs and warfarin in patients with CKD or dialysis patients from database inception until August 2020. The efficacy outcomes were stroke, systemic embolism (SE), or venous thromboembolism (VTE), and the safety outcome was major bleeding.

RESULTS

Compared with warfarin, DOACs significantly reduced the risk of stroke/SE/VTE by 22% (hazard ratio [HR] = 0.78, 95% confidence interval [CI] 0.64-0.95) and major bleeding by 17% (HR = 0.83, 95% CI 0.71-0.97). On comparing factor Xa inhibitors and dabigatran with warfarin separately, factor Xa inhibitors significantly reduced the risk of stroke/SE/VTE (HR = 0.78, 95% CI 0.62-0.98) and major bleeding (HR = 0.76, 95% CI 0.64-0.91) overall in patients. Comparing each DOACs with warfarin separately, apixaban was associated with a significantly better risk reduction of stroke/SE/VTE (25% risk reduction) and major bleeding (35% risk reduction) than warfarin. Compared with warfarin, DOACs significantly reduced the risk of stroke, SE, or VTE by 19% (HR = 0.81, 95% CI 0.68-0.97) in patients with CKD stage 3 and significantly lowered the risk of major bleeding by 31% (HR = 0.69, 95% CI 0.56-0.85) in patients with CKD stages 4-5.

CONCLUSIONS

In pooled, analyzed randomized controlled trials and observational studies, DOACs were associated with better efficacy in early CKD, as well as similar efficacy and safety outcomes to warfarin in patients with CKD stages 4-5 or dialysis patients. The results of patients with CKD stages 4-5 and dialysis patients were from observational studies. Well-designed randomized controlled trials focused on DOAC use in patients with CKD and dialysis patients are needed. PROSPERO register number: CRD42020150599, 6 February, 2020.

Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Renal Dysfunction

Atrial fibrillation and renal dysfunction often coexist, each disorder may predispose to the other and contribute to worsening prognosis. Both atrial fibrillation and chronic kidney disease are associated with increased risk of stroke and thromboembolic complications. Oral anticoagulation for stroke prevention is therefore recommended in patients with atrial fibrillation and decreased renal function. Each direct oral anticoagulant has unique pharmacologic properties of which clinician should be aware to optimally manage patients. The doses of direct oral anticoagulants require adjustment for renal function. There is debate regarding which equation, the Chronic Kidney Disease Epidemiology (CKD-EPI) equation vs. the Cockcroft-Gault equation, should be used to estimate glomerular filtration rate in patients with atrial fibrillation treated with direct oral anticoagulants. Our review tries to find arguments for benefit of direct oral anticoagulants in patients with renal dysfunction.

Relationship between the degree of renal dysfunction and the safety and efficacy outcomes in patients with atrial fibrillation receiving direct oral anticoagulants

BACKGROUND

The clinical evaluation of a direct oral anticoagulant (DOAC) treatment for atrial fibrillation (AF) patients with renal dysfunction has not been sufficiently studied. This study aimed to evaluate the safety and efficacy of DOACs for patients with a severely impaired renal function.

METHODS

This was a retrospective and observational study in a single center. We enrolled 894 consecutive AF patients who were prescribed DOACs, and divided them into three groups based on their creatinine clearance (CrCl) value: CrCl ≥ 50 mL/min group (n = 634), CrCl 30-49 mL/min group (n = 207), and CrCl 15-29 mL/min group (n = 53). We evaluated the occurrence of major bleeding (MB) as the safety outcome and thromboembolic events (TEs) as the efficacy outcome during the follow-up.

RESULTS

The incidence of MB in the CrCl 15-29 mL/min group was significantly higher than in the other groups (CrCl ≥ 50 mL/min group, 0.8/100 person-years; CrCl 30-49 mL/min group, 1.2/100 person-years; CrCl 15-29 mL/min group, 9.0/100 person-years, log rank test, P < .001). On the other hand, there was no significant difference in the incidence of TEs among the three groups. A multivariate analysis using a Cox proportional hazard model adjusted for the age revealed that the CrCl 15-29 mL/min group was significantly associated with increased MB compared to the CrCl ≥ 50 mL/min group (hazard ratio: 9.76, 95% confidence interval: 2.69-35.5, P < .001). Similar results were observed when adjusting for other multiple clinical factors.

CONCLUSION

This study demonstrated that the degree of renal dysfunction was a significant prognostic factor for MB in AF patients receiving DOACs.

Cost-effectiveness of rivaroxaban versus warfarin in non-valvular atrial fibrillation patients with chronic kidney disease in China

WHAT IS KNOWN AND OBJECTIVE

In non-valvular atrial fibrillation (NVAF) patients with chronic kidney disease (CKD), rivaroxaban was not inferior to warfarin in preventing stroke and systemic embolism. However, a comparative evaluation of the cost-effectiveness of rivaroxaban and warfarin therapies for NVAF patients at different renal function levels has not yet been reported, and this study aimed to estimate the cost-effectiveness of rivaroxaban compared with warfarin in Chinese NVAF patients with CKD.

METHODS

A Markov model was constructed to estimate quality-adjusted life years (QALYs) and lifetime costs associated with the use of rivaroxaban relative to warfarin in patients with NVAF at different estimated glomerular filtration rate (eGFR) levels as follows: 30 to <50, 50 to <80 and ≥80 mL/min. Input parameters were sourced from the clinical literature. Probabilistic sensitivity analyses were performed to assess model uncertainty.

RESULTS AND DISCUSSION

The incrementalQALYs with rivaroxaban was slightly increased by approximately 0.3 QALY as compared with that with warfarin in all the subgroups, resulting in an ICER of $9,736/QALY (eGFR, 30 to <50 mL/min), $9,758/QALY (50 to <80 mL/min) and $9,969/QALY (≥80 mL/min). The probabilistic sensitivity analysis suggested a chance of >80% that the ICER would be lower than the willingness-to-pay threshold of three times the GDP of China in 2019 in all the subgroups. Results were consistent even under the assumption of anticoagulant discontinuation after major bleeding events. The model was most sensitive to event-free-related utility and survival rates.

WHAT IS NEW AND CONCLUSION

The existing evidence supports the cost-effectiveness of rivaroxaban therapy as an alternative anticoagulant to warfarin for patients with NVAF at different renal function levels.

[Comparative efficacy and safety of direct oral anticoagulants in patients with atrial fibrillation and chronic kidney disease]

Aim To compare efficacy and safety of direct oral anticoagulants (DOACs) for prevention of stroke in patients with nonvalvular atrial fibrillation and reduced creatinine clearance.Material and methods Systematic search for literature and indirect comparison of DOACs were performed.Results The indirect comparison included five randomized clinical trials. The DOACs were comparable by the efficacy of preventing stroke and systemic embolism. The safety profiles had differences. Apixaban significantly decreased the relative risk of major bleeding compared to rivaroxaban by 27 % (relative risk (RR) 0.73; 95 % confidence interval (CI): 0.55-0.98). The apixaban advantage was even greater in the group of patients with a creatinine clearance &lt;50 ml/min: RR was reduced by 48 % compared to rivaroxaban (RR=0.52; 95 % CI: 0.32-0.84), by 50 % compared to dabigatran 300 mg/day (RR=0.50; 95 % CI: 0.31-0.81), and by 48 % compared to dabigatran 220 mg/day (RR=0.52; 95 % CI: 0.32-0.85)Conclusion The indirect comparison of DOACs showed that their efficacy was comparable. With respect of safety, apixaban is the preferrable DOAC for patients with atrial fibrillation and creatinine clearance below 50 ml/min.

Position paper on the safety/efficacy profile of direct oral anticoagulants in patients with chronic kidney disease. Consensus document from the SIN, FCSA and SISET

Direct oral anticoagulants (DOAC) are mostly prescribed to prevent cardioembolic stroke in patients with non-valvular atrial fibrillation (AF). An increasing number of guidelines recommend DOAC in AF patients with preserved renal function for the prevention of thromboembolism, and an increased use of DOAC in daily practice has been recorded also in elderly patients. Ageing is associated with a reduction in glomerular filtration rate, and impaired renal function, regardless of the cause, increases the risk of bleeding. Multiple medication use (polypharmacy) for treating superimposed co-morbidities is common in both elderly and chronic kidney disease (CKD) patients and drug-drug interaction may cause accumulation of DOAC, thereby increasing the risk of bleeding. The safety profile of DOAC in patients with CKD has not been defined with any certainty, particularly in those with severely impaired renal function or end stage renal disease. This has been due to the heterogeneity of studies and the relative paucity of data. This document reports the position of three Italian scientific societies engaged in the management of patients with atrial fibrillation who are treated with DOAC and present with CKD.

Oral anticoagulation and cardiovascular outcomes in patients with atrial fibrillation and chronic kidney disease in Asian Population, Data from the COOL-AF Thailand registry

BACKGROUND AND OBJECTIVES

Patients with AF and chronic kidney disease(CKD) encountered increased risks of stroke, bleeding, morbidity, and overall mortality. Oral anticoagulation in these populations definitely enhances major bleeding but the benefit of stroke reduction remained inconclusive.The aim of this study is to evaluate the effect of oral anticoagulation (OAC) on the 2-year cardiovascular outcomes in patients with AF and CKD.

METHOD

NVAF patients were consecutively enrolled from 27 hospitals located all across Thailand.Baseline demographic and clinical data were collected within 6 months from enrollment.GFR was calculated using CKD-EPI formula. CKD patients were defined as GFR less than 60 mL/min/1.73 m² according to KDOQI of the National Kidney Foundation. Clinical outcomes included ischemic stroke or transient ischemic attack (TIA) and major bleeding.

RESULTS

At 25.7 ± 10.6 months of follow up, we identified 2538 patients with complete renal follow-up data. Among these were 1594 patients with CKD (stage 3-5) and 944 patients without CKD. The rate of ischemic stroke in patients with and without CKD were 3.7% and 1.7% respectively (p = 0.004),the rate of major bleeding was 5.6 and 3.5% accordingly (p = 0.015) and, likewise, the death rate was substantially high in patients with CKD (10.0% and 6.5%, p = 0.02). The rate of ischemic stroke/TIA in patients with CKD who were and were not on OAC did not differ significantly, 3.6% and 4.2% respectively (p = 0.602). NOAC and warfarin did not differ significantly in the propensity score-matched rate of both ischemic stroke/TIA (0 and 1.2%, p = 0.554) and major bleeding (3.3% and 7.4%, p = 0.122).The net clinical benefit of NOAC over warfarin was 2.153 per 100-patient years.

CONCLUSIONS

COOL AF registry demonstrated that AF patients with CKD had increased risks of ischemic stroke/TIA, major bleeding and death. The benefit of stroke/TIA reduction was not significantly evident for either warfarin or NOAC. However, NOAC was associated with the positive net clinical benefit over no OAC.

Kidney function stratified outcomes of percutaneous left atrial appendage occlusion in patients with atrial fibrillation and high bleeding risk

Background: Patients with chronic kidney disease (CKD) and atrial fibrillation have increased risks for stroke and bleeding under oral anticoagulation (OAC). We investigated an alternative therapy of percutaneous left atrial appendage occlusion (LAAO) in CKD patients in this study.Methods: Consecutive patients undergoing LAAO were included in a retrospective analysis and stratified for kidney function into CKD/Non-CKD groups (cutoff eGFR 60 ml/min). Procedural characteristics, in-hospital and follow-up events were analysed and compared between groups.Results: LAAO was performed in 146 patients (81 CKD; 65 Non-CKD), mean follow-up was 391 days. Groups differed in eGFR (40.1 (CKD) vs. 75.1 (Non-CKD) ml/min) and CHA₂DS₂VASc scores (4.65 ± 1.3 (CKD) vs. 4.06 ± 1.4 (Non-CKD)). Procedural success was 98.6%, contrast-induced acute kidney injury was significantly more frequent in CKD patients (11.1% vs. 0%; p = .004). Follow-up mortality was higher in CKD (10.5/100 PY vs. 4.2/100 PY; p = .156). Follow-up stroke rates were 2.3/100 (CKD) patient-years (PY) and 1.4/100 PY (Non-CKD) (p = 1.000), corresponding to a relative risk reduction (RRR) of 60% (all), 68% (CKD) and 71% (Non-CKD) compared to expected stroke rates. Follow-up major bleeding rates were 3.5/100 PY (CKD) and 4.2/100 PY (Non-CKD), corresponding to RRR of 57% (all), 61% (CKD) and 53% (Non-CKD) compared to OAC.Conclusions: Left atrial appendage occlusion shows comparable efficacy for stroke and bleeding prevention in CKD and Non-CKD patients. CKD patients experience more adverse events during follow-up and a significantly increased risk for periprocedural contrast-induced acute kidney injury.

Position paper on the safety/efficacy profile of Direct Oral Anticoagulants in patients with Chronic Kidney Disease: Consensus document of Società Italiana di Nefrologia (SIN), Federazione Centri per la diagnosi della trombosi e la Sorveglianza delle terapie Antitrombotiche (FCSA) and Società Italiana per lo Studio dell'Emostasi e della Trombosi (SISET)

Direct oral anticoagulants (DOAC) are mostly prescribed to prevent cardioembolic stroke in patients with non-valvular atrial fibrillation (AF). An increasing number of guidelines recommend DOAC in AF patients with preserved renal function for the prevention of thromboembolism and an increased use of DOAC in daily practice is recorded also in elderly patients. Aging is associated with a reduction of glomerular filtration rate and impaired renal function, regardless of the cause, increases the risk of bleeding. Multiple medication use (polypharmacy) for treating superimposed co-morbidities is common in both elderly and chronic kidney disease (CKD) patients and drug-drug interaction may cause accumulation of DOAC, thereby increasing the risk of bleeding. There is uncertainty on the safety profile of DOAC in patients with CKD, particularly in those with severely impaired renal function or end stage renal disease, due to the heterogeneity of studies and the relative paucity of data. This document reports the position of three Italian scientific societies engaged in the management of patients with atrial fibrillation who are treated with DOAC and present with CKD.