Variation of renal function over time is associated with major bleeding in patients treated with direct oral anticoagulants for atrial fibrillation

Real-world evidence comparing oral anticoagulants for NVAF in Europe: a systematic review and network meta-analysis

AIM

Atrial fibrillation is the most commonly sustained cardiac arrhythmia, increasing the risk of stroke and systemic embolic events. This systematic review and network meta-analysis (NMA) aimed to compare real-world evidence (RWE) on the effectiveness and safety of edoxaban with other direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with non-valvular atrial fibrillation (NVAF) in Europe.

MATERIALS & METHODS

Searches from January 2013 to December 2022 identified comparative observational studies assessing effectiveness/safety outcomes in patients with NVAF. Bayesian NMA estimated comparative effectiveness/safety of edoxaban with other DOACs and VKAs.

RESULTS

The review identified 57 studies analyzing data from 24 unique databases; 33 studies were included in the base-case analyses. DOACs showed benefit over VKAs for most outcomes, of which major bleeding and all-cause mortality were most commonly reported. Edoxaban demonstrated a comparable effectiveness/safety profile to other DOACs and significantly reduced risk of major bleeding (hazard ratio [95% credible interval]: 0.67 [0.54, 0.84]) and intracranial hemorrhage (0.69 [0.51, 0.94]) versus rivaroxaban.

CONCLUSION

This NMA provides valuable insights into the real-world effectiveness and safety of DOACs and VKAs in Europe, supporting clinical decision-making and adding to the existing evidence base from clinical trials.

Timing of Off-Label Dosing of Direct Oral Anticoagulants in Three Large Health Systems

BACKGROUND

 While direct oral anticoagulants (DOACs) may be viewed as simpler to manage then warfarin, they present their own unique management challenges resulting in frequent off-label dosing. It is unknown to what extent off-label dosing occurs when a patient is started on a DOAC versus later in their treatment.

OBJECTIVES

 We aimed to better characterize when off-label DOAC dosing is occurring and to evaluate the effectiveness of prescribing oversight using a registry-based intervention.

METHODS

 We evaluated data from the Michigan Anticoagulation Quality Improvement Initiative (MAQI2) registry, a retrospective quality-improvement process using data abstractors, from 2018 to 2022 on the number of "alerts" that are generated in response to dosing deviating from the U.S. Food and Drug Administration instructions for atrial fibrillation (AF) and venous thromboembolism (VTE).

RESULTS

 Among a sample of 789 to 1,022 annual AF patients and 381 to 484 annual VTE patients prescribed a DOAC in the MAQI2 registry, off-label dosing was relatively common. Over the 5-year period (2018-2022), there were 569 alerts for AF patients and 162 alerts for VTE patients. Alerts occurred more frequently during follow-up than at the time of initial prescribing in AF patients (78.2 vs. 21.8%), but more commonly at initial prescribing in VTE patients (59.9 vs. 40.1%). After initial review by quality-improvement abstractors, 19.3% of AF alerts and 14.8% of VTE alerts resulted in contact to the prescriber. When the prescriber was contacted, it led to an intervention about 75% of the time for both populations. The most common intervention was a change in DOAC dosing.

CONCLUSION

 This study demonstrates the benefit of DOAC prescribing oversight using a registry-based intervention to monitor for off-label dosing for the entirety of the time period a patient is prescribed DOAC, particularly for patients with AF, as off-label prescribing occurs frequently during the follow-up period.

Renal function and adverse clinical events in anticoagulated patients with atrial fibrillation: insights from the GLORIA-AF Registry Phase III

Renal function, assessed by creatinine clearance (CrCl), affects the efficacy and safety of oral anticoagulant (OAC) therapy in patients with atrial fibrillation (AF). To investigate the association between CrCl and the risk of clinical adverse events and compare the safety profiles of vitamin K antagonists (VKA) and non-vitamin K antagonist oral anticoagulants (NOAC). Patients with newly diagnosed AF (< 3 months before baseline visit) were collected from the prospective Global Registry on Long-Term Oral Anti-Thrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) registry Phase III. Clinical events assessed included the composite outcome (all-cause death, thromboembolism, and major bleeding), cardiovascular (CV) death, myocardial infarction (MI), and other single outcomes. 10,594 AF patients (mean age 70.35 ± 9.92 years; 55% male; 73% on NOAC) were included. Increasing CrCl was associated with decreased risks of all cause death, composite outcomes and CV-death with in patients with CrCl < 80 mL/min. Multivariate Cox models indicated that compared to VKA, NOAC was associated with lower risks of all cause death (adjusted hazard ratio [aHR] 0.68, 95% CI 0.58-0.78), composite outcomes (aHR 0.77, 95% CI 0.69-0.86), CV-death (aHR 0.70, 95% CI 0.56-0.87), and major bleeding (aHR 0.74, 95% CI 0.61-0.91) in AF patients. For CrCl < 30 mL/min, lower risks of all-cause death, composite outcomes and CV death were related to NOAC therapy. In this large prospective global registry, NOACs were associated with better outcomes compared with VKA for patients with normal or impaired renal function.

An accurate haplotyping method using multiplex pyrosequencing with AS-PCR to detect ABCB1 haplotypes associated with rivaroxaban-derived hemorrhagic events

In clinical practice, owing to the comprehensive genetic insights they offer, haplotypes have attracted greater attention than individual single nucleotide polymorphisms (SNPs). Due to the long distances across SNP locations, detecting the haplotype using genomic DNA is challenging. Current haplotyping methods are either expensive and labor-intensive (high-throughput DNA sequencing), or haplotyping a single clinical sample (computational approach) is impossible. Herein, we propose using mRNA as a haplotyping target to minimize the distance among SNPs and employing allele-specific PCR (AS-PCR) to pick up a desired haplotype, followed by multiplex pyrosequencing to type the alleles at the SNP location of interest. AS-PCR was improved by combining an additional 3'-phosphorylated modified probe to achieve the specific separation of two closely similar templates. Only the sample with more than two heterozygotes needs to be haplotyped; therefore, we propose a stratification strategy to screen the samples for further haplotyping. This method was evaluated by associating ABCB1 haplotypes with the rivaroxaban-derived side effect in a cohort of 505 patients with nephrotic syndrome, focusing on the SNPs of ABCB1: rs1236C > T, rs2677G > T/A, and rs3435C > T. We successfully identified five bleeding-related haplotypes: rs1236T-rs2677T-rs3435T, rs1236C-rs2677G-rs3435T, rs1236T-rs2677G-rs3435C, rs1236C-rs2677G-rs3435C, and rs1236T-rs2677T-rs3435C. We compared the results with those from the conventional computational algorithm PHASE and observed that PHASE results dismissed the impact of rs1236C-rs2677G-rs3435C and rs1236C-rs2677G-rs3435T on bleeding risk and erroneously suggested a false positive association of rs1236C-rs2677A-rs3435T with increased bleeding risk.

Impact of renal function variability on long-term prognosis in ischemic stroke patients with atrial fibrillation

Background

Although renal dysfunction is associated with adverse clinical outcomes in patients with atrial fibrillation (AF) following stroke, the impact of renal function variability is unclear.

Aim

This study aimed to assess the association between renal function variability and various adverse clinical outcomes in patients with transient ischemic attack (TIA)/ischemic stroke and atrial fibrillation (AF).

Methods

We conducted a population-based study and retrospectively identified patients hospitalized with a diagnosis of TIA/ischemic stroke and AF during 2016-2020 using the Clinical Data Analysis and Reporting System of Hong Kong. Serial serum creatinine tested upon the onset of TIA/ischemic stroke and during their subsequent follow-up was collected. Renal function variability was calculated using the coefficient of variation of the estimated glomerular filtration rate (eGFR). Clinical endpoints that occurred during the study period were captured and included ischemic stroke/systemic embolism, intracerebral hemorrhage (ICH), total bleeding, major adverse cardiovascular events (MACE), cardiovascular, non-cardiovascular, and all-cause mortality. Competing risk regression and Cox proportional hazard regression models were used to assess the associations of renal function variability with the outcomes of interest.

Results

A total of 3,809 patients (mean age 80 ± 10 years, 43% men) who satisfied the inclusion and exclusion criteria were followed up for a mean of 2.5 ± 1.5 years (9,523 patient-years). The mean eGFR was 66 ± 22 mL/min/1.73 m2 at baseline, and the median number of renal function tests per patient during the follow-up period was 20 (interquartile range 11-35). After accounting for potential confounders, a greater eGFR variability was associated with increased risks of recurrent ischemic stroke/systemic embolism [fully adjusted subdistribution hazard ratio 1.11, 95% confidence interval (CI) 1.03-1.20], ICH (1.17, 1.01-1.36), total bleeding (1.13, 1.06-1.21), MACE (1.22, 1.15-1.30), cardiovascular (1.49, 1.32-1.69), non-cardiovascular (1.43, 1.35-1.52), and all-cause mortality (fully adjusted hazard ratio 1.44, 1.39-1.50).

Conclusion

Visit-to-visit renal function variability is independently associated with adverse clinical outcomes in TIA/ischemic stroke patients with AF. Further large-scale studies are needed to validate our results.

Comparing the Real-World and Clinical Trial Bleeding Rates Associated with Oral Anticoagulation Treatment for Atrial Fibrillation

Background The prevention of stroke in patients with atrial fibrillation (AF) involves the use of oral anticoagulation, commonly in the form of direct oral anticoagulants (DOACs). However, it comes with an increased risk of bleeding, and therefore, counselling patients on their individual risks is important. Although the majority of patients initiated on DOACs have been represented within the clinical trials, some cohorts are under-represented in whom clinicians cannot practice evidence-based medicine. Methods Utilising the pooled clinical trial (CT) data sourced from Medidata Enterprise Data Store, five recent open-label industry-sponsored AF trials were compared with real-world data (RWD) sourced from the HealthVerity™ Marketplace with the occurrence of bleeding events as the primary outcome of interest. Results A total of 64,421 patients were included in the analysis, with 3207 patients from the clinical DOAC trials and 61,214 patients from the RWD cohort. Overall, the patients from the RWD cohort had more co-morbidities, were older (72.2 ± 11.9 vs. 65.3 ± 10.7 years old, p < 0.001), had higher mean CHA2DS2VASc (3.98 ± 1.9 vs. 2.87 ± 1.73, p < 0.001), and HAD-BLED scores (2.13 ± 1.02 vs. 1/04 ± 0.93, p < 0.001) when compared to the trial data. When comparing the incidence of the first major bleed at 12 months post-treatment initiation, rates in the RWD cohort were significantly higher (10.69 vs. 18.97 per 100 person-years). The impact of co-morbidities such as age, CHA2DS2VASc, and HAD-BLED scores was similar in both cohorts; however, there was an under-representation of older females and more co-morbid patients within the clinical trial cohort. Conclusions DOAC-treated patients have a higher bleeding incidence rate in the RWD cohort than in clinical trials. This can be explained by the older patient age group with more complex medical h istories and higher HAS-BLED scores. The under-representation of higher-risk patients and lower proportion of females within clinical trials should be addressed to better translate clinical trial data into real-world clinical practice.

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

BACKGROUND

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

AIM OF THIS STUDY

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

METHODS

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

RESULTS

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

CONCLUSION

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

Safety and Effectiveness of Apixaban Versus Warfarin in Japanese Patients with Nonvalvular Atrial Fibrillation Stratified by Renal Function: A Retrospective Cohort Study

BACKGROUND

We previously conducted a retrospective cohort study using chart review of oral anticoagulant-naïve Japanese patients with nonvalvular atrial fibrillation (NVAF) that assessed the risk of major bleeding and stroke/systemic embolism (SE) events of apixaban versus warfarin.

METHODS

In this subgroup analysis, we compared the risk of major bleeding and stroke/SE events by stratifying patients into four subgroups matched 1:1 using propensity score matching (PSM) according to baseline creatinine clearance (CrCl; mL/min): ≥ 15 to < 30, ≥ 30 to < 50, ≥ 50 to < 80, and ≥ 80.

RESULTS

Of the 7074 patients in the apixaban group and 4998 in the warfarin group eligible for inclusion in the analysis, 4385 were included in each group after PSM. Incidence rates of major bleeding and stroke/SE events were generally lower with apixaban versus warfarin across the CrCl subgroups. When all patients with a CrCl change of < 0 mL/min per year during the study period (apixaban, n = 3871; warfarin, n = 2635) were stratified into four subgroups based on the magnitude of CrCl decline (median CrCl change [mL/min] per year: - 1.09, - 3.48, - 7.54, and - 36.92 for apixaban, and - 1.10, - 3.65, - 7.85, and - 40.40 for warfarin), the incidence rates of major bleeding and stroke/SE events generally increased with an increasing CrCl decline per year in both groups.

CONCLUSIONS

In Japanese patients with NVAF, the safety and effectiveness of apixaban and warfarin were consistent across different renal subgroups, including those with severe renal impairment. Our results highlight the importance of monitoring renal function variations over time in patients with NVAF.

CLINICALTRIALS

GOV IDENTIFIER

NCT03765242.

Population pharmacokinetics of apixaban in a real-life hospitalized population from the OptimAT study

This study aimed to characterize apixaban pharmacokinetics (PKs) and its variability in a real-world clinical setting of hospitalized patients using a population PK (PopPK) approach. Model-based simulations helped to identify factors that affect apixaban exposure and their clinical significance. A classic stepwise strategy was applied to determine the best PopPK model for describing typical apixaban PKs in hospitalized patients from the OptimAT study (n = 100) and evaluating the associated variability and influencing factors. Apixaban exposure under specific conditions was assessed using the final model. A two-compartment model with first-order absorption and elimination best described the data. The developed PopPK model revealed a major role of renal function and a minor role of P-glycoprotein phenotypic (P-gp) activity in explaining apixaban variability. The final model indicated that a patient with stage 4 chronic kidney disease (creatinine clearance [CLcr] = 15-29 mL/min) would have a 45% higher drug exposure than a patient with normal renal function (CLcr >90 mL/min), with a further 12% increase if the patient was also a poor metabolizer of P-gp. A high interindividual variability in apixaban PKs was observed in a real-life setting, which was partially explained by renal function and by P-gp phenotypic activity. Target apixaban concentrations are reached under standard dosage regimens, but overexposure can rapidly occur in the presence of cumulative factors warranting the development of a predictive tool for tailoring apixaban exposure and its clinical utility in at-risk patients.

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.

Clinical characteristics and risk factors of in-hospital gastrointestinal bleeding in patients with acute myocardial infarction

Background

Gastrointestinal bleeding (GIB) is one of the most serious complications of acute myocardial infarction (AMI) and is correlated with poor outcomes.

Objective

To evaluate the prevalence, risk factors and in-hospital mortality of GIB in patients with AMI.

Methods

This observational case-control study retrospectively enrolled consecutive patients with AMI from the Department of Cardiovascular Medicine and Cardiovascular Surgery of the First Affiliated Hospital of Xi'an Jiaotong University from January 2015 to December 2020. GIB after AMI was identified by International Classification of Diseases (ICD) codes from inpatient medical settings and validated by medical record review. AMI patients without GIB were accordingly classified as the control group. Propensity score matching (PSM) was used to match with the GIB group and the control group. All anonymized clinical data were provided by the Biobank of the First Affiliated Hospital of Xi'an Jiaotong University.

Results

A total of 5,868 AMI patients were enrolled, 0.87% (51/5,868) of whom developed GIB after AMI. On the univariate analysis, history of diabetes, chronic kidney disease, Killip IV, a lower hemoglobin concentration, a higher serum level of creatinine, blood urea nitrogen and D-dimer were closely associated with the risk of GIB (P < 0.05). On the multivariable analysis, a lower hemoglobin concentration (OR: 0.93, 95% CI: 0.89–0.96, P < 0.001) was independently associated with the risk of GIB. Patients with GIB had a much higher in-hospital mortality rate than those without GIB (14.3 vs. 2.1%, P = 0.047). In-hospital mortality among patients with GIB after AMI appeared to be associated with a decreased hemoglobin concentration (OR: 0.93, 95% CI: 0.86–0.99, P = 0.045) and Killip IV (OR: 51.59, 95% CI: 2.65–1,005.30, P = 0.009).

Conclusion

The history of diabetes, poor renal function and heart failure were associated with the high risk of GIB in patients experiencing AMI. The in-hospital mortality in patients with AMI complicating GIB was higher than that in patients without GIB and was associated with a decreased hemoglobin concentration and high Killip classification.

Use of rivaroxaban attenuates renal function impairment in patients with atrial fibrillation: insights of the EMIR study

BACKGROUND

In atrial fibrillation (AF) patients on vitamin K antagonists, a progressive deterioration of renal function is common but there is limited evidence with long-term use of rivaroxaban. Herein, we investigated the change in renal function in AF patients after 2 years of rivaroxaban treatment.

METHODS

The EMIR registry is an observational and multicentre study including AF patients treated with rivaroxaban for at least 6 months prior to inclusion. Changes in analytical parameters were recorded during 2 years of follow-up. Renal function was estimated using the Cockroft-Gault equation.

RESULTS

1433 patients (638, 44.5% women, mean age of 74.2 ± 9.7 years) were included. Creatinine clearance (CrCl) was available at baseline and at 2 years in 1085 patients. At inclusion, 33.2% of patients had impaired renal function (CrCl <60 ml/min). At 2 years, we were not able to find changes in the proportion of patients with impaired renal function, which increased to 34.6% (p = 0.290). However, the baseline mean CrCl was 76.0 ± 30.5 ml/min and slightly improved at 2 years (77.0 ± 31.8 ml/min; p = 0.014). Overall, the proportion of patients with CrCl <60 ml/min at baseline that had CrCl ≥60 ml/min at 2 years was significantly higher compared to that of patients with CrCl ≥60 ml/min at baseline and CrCl <60 ml/min after (22.2% vs. 13.1%; p < 0.001) CONCLUSIONS: In AF patients on long-term rivaroxaban therapy, a decrease in renal function was not observed. We even observed a slight improvement in the patients with renal impairment. These results reinforce the idea that rivaroxaban may be a safe option even in patients with renal impairment.

Direct Oral Anticoagulants in Old and Frail Patients with Atrial Fibrillation: The Advantages of an Anticoagulation Service

Despite the recent advancements, oral anticoagulation is still challenging in some patients and this is the case for old and frail patients. The large majority of frail patients with atrial fibrillation should receive anticoagulation since the associated benefits outweigh the risk of bleeding. A multidisciplinary consensus document on the use and prescription of direct oral anticoagulants (DOACs) in older and frail patients with atrial fibrillation has been recently published. In this manuscript we provide a comment on this document and add insights into the management of these patients. The new DOAC age had imposed a paradigm shift in the management of patients with the need for clinically-oriented services rather than laboratory-oriented services. In this paper we provide tools for a structured patient-oriented DOACs treatment service supported by a multidisciplinary approach.

The Connubium among diabetes, chronic kidney disease and atrial fibrillation

The burden of cardiovascular comorbid conditions was significantly higher in patients with Atrial Fibrillation (AF); most of them are affected by hypertension, Chronic Kidney Disease (CKD) and/or Diabetes Mellitus (DM). DM represents a well-known risk factor for the development and maintenance of AF; the coexistence of DM and AF is also associated with an increased risk of mortality and stroke. Moreover, DM is currently the main cause of renal impairment and the leading cause of dialysis in the world. The hyperglycemia is responsible for inducing redox imbalance and both systemic and intrarenal inflammation, playing a critical role in the pathogenesis of diabetic kidney disease. Long-term thromboembolic preventive therapy in AF patients with DM and CKD may be more challenging because both DM and CKD have been independently associated with an increased thromboembolic and bleeding risk, which results from the prothrombotic and pro-inflammatory status. Vitamin K Antagonists (VKAs) are characterized by numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavourable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. On the other hand, Direct Oral Anticoagulants (DOACs) are currently contraindicated in dialysis patients even if mounting evidence suggests that they may have a nephroprotective role in AF patients with DM and CKD. Consequently, the choice of anticoagulant therapy in this setting of patient seems to be very challenging. The aim of this review is to investigate the role of DOACs in diabetic patients and its nephroprotective role by reviewing the current literature.

Risk factors and one-year mortality in patients with direct oral anticoagulant-associated gastrointestinal bleeding

BACKGROUND AND AIM

Risk factors and mortality in patients with DOACs-associated gastrointestinal bleeding (GIB) are not completely defined. Aims of this study were to identify risk factors for bleeding and evaluate one-year mortality in patients with DOACs-associated GIB.

METHODS

We conducted a case-control study. Cases were patients with DOACs-associated GIB admitted to the Perugia Hospital, Italy between 2013 and 2019. Controls were derived from the prospective database of patients with DOACs referred to the ambulatory service. Cases and controls were matched by a 1:2 ratio for type and dose of DOAC, indication for anticoagulation and gender. Univariate and multivariable analyses were performed to identify risk factors. Hazard Ratio with 95% confidence interval was used to calculate mortality.

RESULTS

We included 324 patients, of which 108 with DOACs-associated GIB. Mean age was 81.9 ± 7.2 years and 78.9 ± 8.7 years, respectively. The most frequent indication for anticoagulation was atrial fibrillation. Reduced doses of DOACs were prescribed in 186 patients (56.4%). At multivariable analysis, active cancer (OR:7.26; 95%CI 3.10-16.96), renal impairment (OR:4.26; 95%CI 1.98-9.17), bleeding predisposition (OR:3.66; 95%CI 2.00-6.68), COPD (OR:2.12; 95%CI 1.08-4.16) and uncontrolled hypertension (OR:1.86; 95%CI 1.07-3.23) were found to be predictors for DOACs-associated GIB. Adjusted one-year mortality was significantly higher in patients who experienced GIB compared with those who did not experience GIB (OR: 7.04; 95%CI 3.82-14.31).

CONCLUSIONS

Predictors of DOACs-associated GIB included active cancer, renal impairment, bleeding predisposition, COPD and uncontrolled hypertension. The adjusted one-year-mortality was significantly increased in patients with DOACs-associated GIB in comparison to DOACs patients without GIB.

Prediction of bleeding events using the VTE-BLEED risk score in patients with venous thromboembolism receiving anticoagulant therapy (Review)

Venous thromboembolism (VTE) is a major healthcare problem due to its high incidence, significant mortality rate from pulmonary embolism, high recurrence rate and morbidity from long-term complications. After a first episode of VTE all patients must receive anticoagulant treatment for 3 months. Further anticoagulation is recommended in patients without transient risk factors for VTE or patients with active cancer, if they are not at a high risk for bleeding. The VTE-BLEED risk score was created with the purpose of enabling a better stratification of the bleeding risk during stable anticoagulation after a first VTE. Currently, it is the most validated risk score in VTE settings (selected and non-selected cohorts). It has a good prediction power for major bleeding events in patients receiving any of the currently available classes of oral anticoagulants, and it can identify patients at risk of intracranial and fatal bleeding events. The aim of our review was to highlight the strengths of the VTE-BLEED risk score, to acknowledge its weak points and to properly position its use in current medical practice.

Non-valvular Atrial Fibrillation in CKD: Role of Vitamin K Antagonists and Direct Oral Anticoagulants. A Narrative Review

Atrial fibrillation (AF) is the most common arrhythmia in chronic kidney disease (CKD), with a close bidirectional relationship between the two entities. The presence of CKD in AF increases the risk of thromboembolic events, mortality and bleeding. Vitamin K antagonists (VKA) have been the mainstay of treatment for the prevention of thromboembolic events in AF until recently, with confirmed benefits in AF patients with stage 3 CKD. However, the risk-benefit profile of VKA in patients with AF and stages 4-5 CKD is controversial due to the lack of evidence from randomized controlled trials. Treatment with VKA in CKD patients has been associated with conditions such as poorer anticoagulation quality, increased risk of bleeding, faster progression of vascular/valvular calcification and higher risk of calciphylaxis. Direct oral anticoagulants (DOACs) have shown equal or greater efficacy in stroke/systemic embolism prevention, and a better safety profile than VKA in post-hoc analysis of the pivotal randomized controlled trials in patients with non-valvular AF and stage 3 CKD, yet evidence of its risk-benefit profile in more advanced stages of CKD is scarce. Observational studies associate DOACs with a good safety/effectiveness profile compared to VKA in non-dialysis CKD patients. Further, DOACs have been associated with a lower risk of acute kidney injury and CKD development/progression than VKA. This narrative review summarizes the evidence of the efficacy and safety of warfarin and DOACs in patients with AF at different CKD stages, as well as their effects on renal function, vascular/valvular calcification and bone health.

Direct Oral Anticoagulants: From Randomized Clinical Trials to Real-World Clinical Practice

Direct oral anticoagulants (DOACs) are a more manageable alternative than vitamin K antagonists (VKAs) to prevent stroke in patients with nonvalvular atrial fibrillation and to prevent and treat venous thromboembolism. Despite their widespread use in clinical practice, there are still some unresolved issues on optimizing their use in particular clinical settings. Herein, we reviewed the current clinical evidence on uses of DOACs from pharmacology and clinical indications to safety and practical issues such as drugs and food interactions. Dabigatran is the DOAC most affected by interactions with drugs and food, although all DOACs demonstrate a favorable pharmacokinetic profile. Management issues associated with perioperative procedures, bleeding treatment, and special populations (pregnancy, renal and hepatic impairment, elderly, and oncologic patients) have been discussed. Literature evidence shows that DOACs are at least as effective as VKAs, with a favorable safety profile; data are particularly encouraging in using low doses of edoxaban in elderly patients, and edoxaban and rivaroxaban in the treatment of venous thromboembolism in oncologic patients. In the next year, DOAC clinical indications are likely to be further extended.

Evaluation of Anti-Xa Apixaban and Rivaroxaban Levels With Respect to Known Doses in Relation to Major Bleeding Events

BACKGROUND

Although not routinely recommended, anti-Xa level monitoring for apixaban or rivaroxaban may be useful in certain clinical scenarios. There are currently no laboratory standards, therapeutic ranges, or proven correlation between anti-Xa levels and clinical outcomes.

OBJECTIVE

This study describes the utilization, application, and association of anti-Xa levels with clinical outcomes in patients receiving apixaban or rivaroxaban.

METHODS

This retrospective, descriptive study included adult inpatients within the Houston Methodist System on apixaban or rivaroxaban with at least one anti-Xa level ordered subsequent to administered doses. The primary endpoint was major bleeding according to International Society on Thrombosis and Haemostasis criteria. Secondary endpoints included reasons for anti-Xa level ordering, anti-Xa levels at different time intervals post-dose, and thrombotic events. Pre-specified subgroup analyses were performed to further evaluate the primary endpoint.

RESULTS

The study population consisted of 169 patients and 234 anti-Xa levels. Twenty-nine levels were obtained in context of major bleeding. The majority of levels were not drawn as peak levels 2-4 hours post-dose, however remained quantifiable above typical observed levels within this timeframe and well beyond 24 hours post-dose. Patient characteristics with major bleeding included elderly age, acute renal impairment, and low body weight. At least 14 unique reasons for anti-Xa level ordering were identified. Twenty-nine levels were associated with thrombotic events.

CONCLUSION

Anti-Xa levels may be useful for assessment of current drug concentrations, immediate safety of therapy, and guidance for possible clinical interventions. Dose titration and reversal therapies based on anti-Xa level results in major bleeding warrant further research.

Incidence and predictors of hospitalization in patients with atrial fibrillation: results from the Chinese atrial fibrillation registry study

Background

Patients with atrial fibrillation (AF) underwent a high risk of hospitalization, which has not been paid much attention to in practice. Therefore, we aimed to assess the incidence, causes and predictors of hospitalization in AF patients.

Methods

From August 2011 to December 2017, a total number of 20,172 AF patients from the Chinese Atrial Fibrillation Registry (China-AF) Study were prospectively selected for this study. We described the incidence, causes of hospitalization by age groups and sex. The Fine-Gray competing risk model was employed to identify predictors of first all-cause and first cause-specific hospitalization.

Results

After a mean follow-up of 37.3 ± 20.4 months, 7,512 (37.2%) AF patients experienced one or more hospitalizations. The overall incidence of all-cause hospitalization was 24.0 per 100 patient-years. Patients aged < 65 years were predominantly hospitalized for AF (42.1% of the total hospitalizations); while patients aged 65–74 and ≥ 75 years were mainly hospitalized for non-cardiovascular diseases (43.6% and 49.3%, respectively). We found patients complicated with heart failure (HF)[hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.02–1.18], established coronary artery disease (CAD) (HR 1.24, 95%CI 1.17–1.33), ischemic stroke/transient ischemic attack (TIA) (HR 1.22, 95%CI 1.15–1.30), diabetes (HR 1.14, 95%CI 1.08–1.20), chronic obstructive pulmonary disease (COPD) (HR 1.28, 95%CI 1.02–1.62), gastrointestinal disorder (HR 1.37, 95%CI 1.21–1.55), and renal dysfunction (HR 1.24, 95%CI 1.09–1.42) had higher risks of hospitalization.

Conclusions

More than one-third of AF patients included in this study were hospitalized at least once during over 3-year follow-up. The main cause for hospitalization among the elderly patients (≥ 65 years) is non-cardiovascular diseases rather than AF. Multidisciplinary management of comorbidities should be advocated to reduce hospitalization in AF patients older than 65 years old.

Clinical Registryhttp://www.chictr.org.cn/showproj.aspx?proj=5831. Unique identifier: ChiCTR-OCH-13003729. The registration date is October 22, 2013.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-01951-5.

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.

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.

What gastroenterologists should know about direct oral anticoagulants

Direct oral anticoagulants are being increasingly used in patients with non-valvular atrial fibrillation and venous thromboembolism, due to their improved efficacy/ safety ratio, a predictable anticoagulant effect without need for routine coagulation monitoring, and fewer food and drug interactions compared with vitamin K antagonists. Gastrointestinal bleeding remains a serious complication, whose management is challenging for gastroenterologists due to the lack of a standardized clinical approach. Clinical experience on periendoscopic management of these drugs is still limited and there is a paucity of clinical data supporting guidelines recommendations', and this ultimately turns out in different, unsubstantiated and potentially harmful practices of patient management. Present study will provide a thorough revision on the risk of GI bleeding for DOAC therapy and the identification of patient risk factors to individualize treatment. Moreover, the approach to management of DOACs in case of bleeding complications is discussed, and an algorithm of different strategies in presence or not of plasma level measurement is proposed. Finally the periendoscopic management for elective procedures will be reviewed, at the light of the guideline recommendations and new evidences from observational studies.

Applying population health approaches to improve safe anticoagulant use in the outpatient setting: the DOAC Dashboard multi-cohort implementation evaluation study protocol

BACKGROUND

Use of direct oral anticoagulants (DOAC) is rapidly growing for treatment of atrial fibrillation and venous thromboembolism. However, incorrect dosing of these medications is common and puts patients at risk of adverse drug events. One way to improve safe prescribing is the use of population health tools, including interactive dashboards built into the electronic health record (EHR). As such tools become more common, exploring ways to understand which aspects are effective in specific settings and how to effectively adapt and implement in existing anticoagulation clinics across different health systems is vital.

METHODS

This three-phase project will evaluate a current nation-wide implementation effort of the DOAC Dashboard in the Veterans Health Administration (VHA) using both quantitative and qualitative methods. Informed by this evaluation, the DOAC Dashboard will be implemented in four new health systems using an implementation strategy derived from the VHA experience and interviews with providers in those new health systems. Quantitative evaluation of the VHA and non-VHA implementation will follow the Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework. Qualitative interviews with stakeholders will be analyzed using the Consolidated Framework for Implementation Research and Technology Acceptance Models to identify key determinants of implementation success.

DISCUSSION

This study will (1) evaluate the implementation of an EHR-based population health tool for medication management within a large, nation-wide, highly integrated health system; (2) guide the adoption in a set of four different health systems; and (3) evaluation that multi-center implementation effort. These findings will help to inform future EHR-based implementation efforts in a wide variety of health care settings.

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.

Direct oral anticoagulants for patients aged over 80 years in nonvalvular atrial fibrillation: the impact of frailty

AIMS

In patients aged at least 80 years, atrial fibrillation is responsible for significant morbidity and mortality, with a high incidence of stroke. Four new direct oral anticoagulants (DOACs) have been introduced in Italy for the prevention of thromboembolism. Their safety and efficacy in the elderly have already been confirmed. Frailty is frequently associated with aging, but only a few studies have paid attention to interactions between frailty and anticoagulation therapy.

METHODS

We retrospectively evaluated the effectiveness and safety of DOACs in a population aged at least 80 years. Frailty was appraised using an adaptation of the Reported Edmonton Frail Scale, considering a value at least 8 (on a scale from 0 to 18).

RESULTS

The majority (644/731) of patients remained on DOACs for more than 1 year. A total of 19 patients experienced a thrombotic event while on anticoagulation (1.11 events per 100 person-years) and 26 patients a major bleeding episode (1.52 events per 100 person-years). The probability of interrupting therapy increased significantly with frailty [hazard ratio 2.91 with confidence interval (CI) 2.15-3.92 at univariate analysis, hazard ratio 2.80 with CI 2.03-3.86 at multivariate]; frailty showed a significant impact also on major bleeding (hazard ratio 3.28 with CI 1.45-7.37 at univariate analysis, hazard ratio 3.56 with CI 1.58-8.01 at multivariate).

CONCLUSION

Our study highlights how DOACs are a safe and effective option for anticoagulation, even in frail elderly people; the introduction of these drugs is leading to an increased use of anticoagulation therapy in this population. Prospective trials will be needed to reinforce these results and to consider new variables in the thrombotic and hemorrhagic risk scores underlying the prescription of DOACs.

Clinical Discussions in Antithrombotic Therapy Management : A Delphi Consensus Panel

For some years now, direct-acting oral anticoagulants (DOACs) have entered the clinical practice for stroke prevention in non-valvular atrial fibrillation (NVAF) or prevention and treatment of venous thromboembolism (VTE). However, there is uncertainty on DOAC use in some clinical scenarios not fully explored by clinical trials, but commonly encountered in the real world. We report a Delphi Consensus on DOAC use in NVAF and VTE patients. The consensus dealt with 16 main topics: (1) clinical superiority of DOACs compared to VKAs; (2) DOACs as a first-line treatment in patients with AF; (3) therapeutic options for patients undergoing electrical cardioversion; (4) selection of patients suitable for switching from VKAs to DOACs; (5) and (7) role of general practitioners in the follow-up of patients receiving a DOAC; (6) duties of Italian oral anticoagulation therapy centers; (8) role of therapy with DOACs in oncological patients with NVAF; (9) role of DOACs in oncological patients with VTE; (10) methods for administration and therapy compliance for DOACs; (11) drug interactions; (12) safety of low doses of DOACs; (13) therapeutic management of frail patients with NVAF; (14) therapeutic management of NVAF patients with glomerular filtration rate <30 ml/min (15); advantages of DOACs for the treatment of frail patients; (16) limitations on therapeutic use of DOACs. Sixty-two cardiologists from Italy expressed their level of agreement on each statement by using a 5-point Likert scale (1: strongly disagree, 2: disagree, 3: somewhat agree, 4: agree, 5: strongly agree). Namely, votes 1-2 were considered as disagreement while votes 3-5 as agreement. Agreement among the respondents of ≥66% for each statement was considered consensus. A brief discussion about the results for each topic is also reported.

Pharmacokinetics and pharmacodynamics of oral anticoagulants used in atrial fibrillation

INTRODUCTION

The availability of non-vitamin K antagonist oral anti-coagulants alongside vitamin K antagonists has offered a variety of options for anti-coagulation, but has also necessitated a good understanding of the pharmacological properties of each of these drugs prior to their use, to maximise the therapeutic benefit and minimise patient harm Areas covered: This review article outlines the pharmacokinetic and pharmacodynamic profiles of the currently licensed VKAs and NOACs that are most commonly used in clinical practice, with the aim of demonstrating how variations in these characteristics influence their use in clinical practice. A literature search was conducted on PubMed using keywords and relevant articles published by the 31^st of December 2018 were included. Expert opinion: The effect of a drug is determined by a combination of elements which include patient characteristics and external factors, in addition to its pharmacokinetic and pharmacodynamic properties. A good understanding of these is essential. Despite the wealth of information available, particularly on VKAs, our knowledge on the pharmacology responsible for certain drug effects and inter-individual variations is still limited. Increasing efforts are being made to understand these and include focus on pharmacogenomics and drug transporter proteins.

[Treatment with oral anticoagulants in older patients: Should warfarin still be prescribed?]

Vitamin-K antagonists (VKA) have been the standard for oral anticoagulation. However, they carry several problems in older patients: frequent bleeding complications, complex management, risk of interactions with multiple drugs. Two classes of direct oral anticoagulants (DOA) are currently available in France: (a) direct thrombin inhibitors: dabigatran; and (b) direct factor Xa inhibitors: rivaroxaban, apixaban and others. Their management is easier: quickly effective after administration, they are given at fixed doses and do not need regular laboratory monitoring. Several randomized trials have shown that DOA are non-inferior to VKA for treating venous thromboembolic disease (prophylactic or curative treatment) and atrial fibrillation (prevention of associated embolisms). DOA might be also effective for long-term treatment of coronary disease, in some cases. No trial has specifically studied older patients. In the context of atrial fibrillation, subgroup analysis show similar results between patients above and below 75-years-old. Lower doses of dabigatran and apixaban should be used in many older people. All DOA are eliminated at least partly by kidneys. Their dose must be reduced in moderate renal failure (filtration glomerular rate (FGR) 30 to 50mL/min) and they are contraindicated in older patients with severe renal failure (FGR<30mL/min). DOA also have other problems: (a) important drug interactions are still possible, (b) the clinical application of specific coagulation tests need to be defined, (c) their safety in some subgroups of elderly patients, very different from patients included in clinical trials, is not known.

The use of direct oral anticoagulants in chronic kidney disease

Increasing use of direct oral anticoagulants (DOACs) has made management of non-valvular atrial fibrillation and venous thromboembolism easier in most patients. But the presence of co-existing renal impairment could render the use of DOACs problematic because all of these drugs have varying degrees of renal excretion. In this paper we address misconceptions about the safety and efficacy of DOACs in moderate-severe renal impairment by presenting a summary of the literature from phase III trials and real-world studies. It also addresses the important consideration of correct estimate of renal function for DOAC dosing. It is hoped that the review will serve as a valuable resource for clinicians involved in anticoagulation decision-making in patients with renal impairment to guide the choice of most suitable agent. Accurate dosing is of particular relevance as registry data suggests it is done inconsistently and may be resulting in avoidable thromboembolic and bleeding events.