Racial and Ethnic Disparities in Initiation of Direct Oral Anticoagulants Among Medicare Beneficiaries.

Importance: The influence of race and ethnicity on initiation of direct oral anticoagulants (DOACs) is relatively understudied in Medicare data. Objective: To investigate disparities in the initiation of DOACs compared with warfarin by race, ethnicity, and social vulnerability. Design, Setting, and Participants: This retrospective cohort study used a 50% sample of Medicare fee-for-service data from January 1, 2010, to December 31, 2019 (mean patient enrollment duration, 7.7 years). Analysis took place between January 2023 and February 2024. A cohort of older adults (aged ≥65 years) with atrial fibrillation who newly initiated warfarin or DOACs (dabigatran, rivaroxaban, apixaban, and edoxaban) was identified. Exposure: Patients were classified as non-Hispanic White, non-Hispanic Black, and Hispanic. Main Outcomes and Measures: The likelihood of starting use of DOACs compared with warfarin was modeled, adjusting for race, ethnicity, age, sex, county-level social vulnerability, and other clinical factors. Results: Among 950 698 anticoagulation initiations, consisting of 680 974 DOAC users and 269 724 warfarin users (mean [SD] age, 78.5 [7.6] years; 52.6% female), 5.2% were Black, 4.3% were Hispanic, and 86.7% were White. During the 10-year study period, DOAC use increased for all demographic groups. After adjustment, compared with White patients, Black patients were 23% less likely (adjusted odds ratio [AOR, 0.77; 95% CI, 0.75-0.79) and Hispanic patients were 13% less likely (AOR, 0.87; 95% CI, 0.85-0.89) to initiate DOAC use. Disparities in DOAC initiation were greatest among Black patients in the earlier years but attenuated during the study period. For instance, in 2010, the OR of Black patients initiating DOACs was 0.54 (95% CI, 0.50-0.57), attenuating linearly over time to 0.69 by 2013 (95% CI, 0.65-0.74) and 0.83 (95% CI, 0.78-0.89) by 2017. By 2019, these differences became nonsignificant (OR, 1.08; 95% CI, 0.99-1.18). Conclusions and Relevance: In this cohort study of Medicare patients with atrial fibrillation, Black and Hispanic patients were less likely to initiate DOACs for atrial fibrillation, although these differences diminished over time. Identifying the factors behind these early disparities is crucial for ensuring equitable access to novel therapies as they emerge for Black and Hispanic populations.

Predictors of adherence to direct oral anticoagulants after cardiovascular or bleeding events in Medicare Advantage Plan enrollees with atrial fibrillation.

BACKGROUND: Direct oral anticoagulants (DOACs) are recommended for patients with atrial fibrillation (AF) given their improved safety profile. Suboptimal adherence to DOACs remains a significant concern among individuals with AF. However, the extent of adherence to DOACs following a cardiovascular or bleeding event has not been fully evaluated. OBJECTIVE: To evaluate the pattern of adherence trajectories of DOACs after a cardiovascular or bleeding event and to investigate the sociodemographic and clinical predictors associated with each adherence trajectory by using claims-based data. METHODS: This retrospective study was conducted among patients with AF prescribed with DOACs (dabigatran/apixaban/rivaroxaban) between July 2016 and December 2017 and who were continuously enrolled in the Texas-based Medicare Advantage Plan. Patients who experienced a cardiovascular or bleeding event while using the DOACs were further included in the analysis. The sample was limited to patients who experienced a clinical event such as a cardiovascular or bleeding event while using the DOACs. The clinical events considered in this study were cardiovascular (stroke, congestive heart failure, myocardial infarction, systemic embolism) and bleeding events. To assess adherence patterns, each patient with a DOAC prescription was followed up for a year after experiencing a clinical event. The monthly adherence to DOACs after these events was evaluated using the proportion of days covered (PDC). A group-based trajectory model incorporated the monthly PDC to classify groups of patients based on their distinct patterns of adherence. Predictors associated with each trajectory were assessed using a multinomial logistic regression model, with the adherent trajectory serving as the reference group in the outcome variable. RESULTS: Among the 694 patients with AF who experienced clinical events after the initiation of DOACs, 3 distinct adherence trajectories were identified: intermediate nonadherent (30.50%), adherent (37.7%), and low adherent (31.8%); the mean PDC was 0.47 for the intermediate nonadherent trajectory, 0.93 for the adherent trajectory, and 0.01 for low adherent trajectory. The low-income subsidy was significantly associated with lower adherence trajectories (odds ratio [OR] = 4.81; 95% CI = 3.07-7.51) and with intermediate nonadherent trajectories (OR = 1.57; 95% CI = 1.06-2.34). Also, nonsteroidal anti-inflammatory drug use was significantly associated with lower adherence trajectories (OR = 5.10; 95% CI = 1.95-13.36) and intermediate nonadherent trajectories (OR = 3.17; 95% CI = 1.26-7.93). Other predictors significantly associated with both nonadherent trajectories are type of DOACs (OR = 0.53; 95% CI = 0.35-0.79), presence of coronary artery disease (OR = 1.89; 95% CI = 1.01-3.55), and having 2 or more clinical events (OR = 1.65; 95% CI = 1.09-2.50). CONCLUSIONS: Predictors identified provide valuable insights into the suboptimal adherence of DOACs among Medicare Advantage Plan enrollees with AF, which can guide the development of targeted interventions to enhance adherence in this high-risk patient population.

Effect of different oral anticoagulants on cognitive function in patients with atrial fibrillation: A Bayesian network meta-analysis.

BACKGROUND: Atrial fibrillation (AF) is 1 of the most common types of arrhythmias. At present, the treatment for patients with AF mainly includes oral anticoagulants (OACs). Studies have shown that OACs are associated with cognitive decline in patients with atrial fibrillation; however, there is a lack of relevant evidence. This study used Bayesian network meta-analysis (NMA) to investigate the effects of different oral anticoagulants on cognitive decline in patients with AF. METHODS: We systematically searched for clinical studies on oral anticoagulants in patients with AF in PubMed, Web of Science, Embase, and the Cochrane Library as of July 3, 2023. Cochrane's randomized controlled trial bias risk assessment tool and the Newcastle-Ottawa Scale were used to assess the bias risk of the included studies. The main outcome measure was decreased cognitive functioning. RESULTS: Ten studies were included, including 2 RCTs and 7 RCSs, including 882,847 patients with AF. Five oral anticoagulants and 2 anticoagulants were included: VKAs (especially warfarin), Dabigatran, Edoxaban, Rivaroxaban, Apixaban, and Aspirin, Clopidogrel. The results of the mesh meta-analysis showed that VKAs were superior to warfarin in reducing the risk of cognitive decline in patients with AF (OR = -1.19, 95% CI (-2.35, -0.06), P < .05) (Table 5). The top 3 drugs in terms of the probability of reducing the incidence of cognitive impairment in patients with AF with different oral anticoagulants were VKAs (87%), rivaroxaban (62.2%), and dabigatran (60.8%). CONCLUSION: Based on the results of this study, VKAs may be the best intervention measure for reducing the risk of cognitive decline in patients with AF. Owing to the limitations of this study, more high-quality randomized controlled trials with large sample sizes and multiple centers are required to provide more evidence.

Appropriateness of prescribing profiles and intake adherence to non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: analysis of a retrospective longitudinal study using real-world data from Northern Portugal (AF-React Study).

OBJECTIVES: This study aimed to assess the appropriateness of prescribing profiles and intake adherence to non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF). DESIGN: Retrospective longitudinal study. SETTING: The study was conducted in the Regional Health Administration of Northern Portugal. PARTICIPANTS: The authors selected a database of 21 854 patients with prescriptions for NOACs between January 2016 and December 2018 and were classified with AF until December 2018. OUTCOME MEASURES: The appropriate dosage of NOAC for patients with AF divided into three categories: contraindicated, inconsistent and consistent, based on the 2020 European Society of Cardiology guidelines for AF. RESULTS: Dabigatran had a lower percentage of guideline-consistent doses (n=1657, 50.1%) than other drugs such as rivaroxaban (n=4737, 81.6%), apixaban (n=3830, 78.7%) and edoxaban (n=436, 82.1%). Most patients with an inconsistent dose were prescribed a lower dose than recommended based on their glomerular filtration rate (GFR). Among patients younger than 75 years with GFR >60 mL/min, 59.8% (n=10 028) had an adequate GFR range, while 27.8% (n=7166) of GFR measurements from patients older than 75 years old and 29.4% (n=913) of GFR measurements from patients younger than 75 years with GFR <60 mL/min were within an adequate time range. Adherence to NOACs varied across different drugs, with 59.1% (n=540) adhering to edoxaban, 56.3% (n=5443) to rivaroxaban, 55.3% (n=3143) to dabigatran and 53.3% (n=4211) to apixaban. CONCLUSIONS: Dabigatran had the lowest percentage of guideline-consistent doses. Patients younger than 75 years with GFR >60 mL/min had the highest percentage with an adequate GFR range, while other groups who require closer GFR monitoring had lower percentages within an adequate GFR range. Adherence to NOACs differed among different drugs, with greater adherence to treatment with edoxaban and less adherence to apixaban.

In Vitro Simulation of the Fasted Gastric Conditions and Their Variability to Elucidate Contrasting Properties of the Marketed Dabigatran Etexilate Pellet-Filled Capsules and Loose Pellets.

Variability of the gastrointestinal tract is rarely reflected in in vitro test protocols but often turns out to be crucial for the oral dosage form performance. In this study, we present a generation method of dissolution profiles accounting for the variability of fasted gastric conditions. The workflow featured 20 biopredictive tests within the physiological variability. The experimental array was constructed with the use of the design of experiments, based on three parameters: gastric pH and timings of the intragastric stress event and gastric emptying. Then, the resulting dissolution profiles served as a training data set for the dissolution process modeling with the machine learning algorithms. This allowed us to generate individual dissolution profiles under a customizable gastric pH and motility patterns. For the first time ever, we used the method to successfully elucidate dissolution properties of two dosage forms: pellet-filled capsules and bare pellets of the marketed dabigatran etexilate product Pradaxa. We showed that the dissolution of capsules was triggered by mechanical stresses and thus was characterized by higher variability and a longer dissolution onset than observed for pellets. Hence, we proved the applicability of the method for the in vitro and in silico characterization of immediate-release dosage forms and, potentially, for the improvement of in vitro-in vivo extrapolation.

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

BACKGROUND: Concomitant atrial fibrillation and end-stage renal disease is common and associated with an unfavorable prognosis. Although oral anticoagulants have been well established to prevent thromboembolism, the applicability in patients under long-term dialysis remains debatable. The study aimed to determine the efficacy and safety of anticoagulation in the dialysis-dependent population. METHODS AND RESULTS: An updated network meta-analysis based on MEDLINE, EMBASE, and the Cochrane Library was performed. Studies published up to December 2022 were included. Direct oral anticoagulants (DOACs, dabigatran, rivaroxaban, apixaban 2.5/5 mg twice daily), vitamin K antagonists (VKAs), and no anticoagulation were compared on safety and efficacy outcomes. The outcomes of interest were major bleeding, thromboembolism, and all-cause death. A total of 42 studies, including 3 randomized controlled trials, with 185 864 subjects were pooled. VKAs were associated with a significantly higher risk of major bleeding than either no anticoagulation (hazard ratio [HR], 1.47; 95% CI, 1.34-1.61) or DOACs (DOACs versus VKAs; HR, 0.74 [95% CI, 0.64-0.84]). For the prevention of thromboembolism, the efficacies of VKAs, DOACs, and no anticoagulation were equivalent. Nevertheless, dabigatran and rivaroxaban were associated with fewer embolic events. There were no differences in all-cause death with the administration of VKAs, DOACs, or no anticoagulation. CONCLUSIONS: For dialysis-dependent populations, dabigatran and rivaroxaban were associated with better efficacy, while dabigatran and apixaban demonstrated better safety. No anticoagulation was a noninferior alterative, and VKAs were associated with the worst outcomes.

Perioperative Treatment with Rivaroxaban and Dabigatran on Changes of Coagulation and Platelet Activation Biomarkers following Left Atrial Appendage Closure.

Insufficient data exist regarding the investigation of the impact of novel oral anticoagulants (NOACs) on coagulation activation biomarkers in the context of left atrial appendage closure (LAAC) and device-related thrombosis (DRT). The study was designed to investigate the changes and presence of coagulation activation biomarkers between different antithrombotic strategies following LAAC. A total of 120 nonvalvular atrial fibrillation patients intolerant of long-term anticoagulants, who underwent successful WATCHMAN closure implantation, were enrolled (rivaroxaban, n = 82; dabigatran, n = 38). Blood samples were obtained from left atrium (LA) and left atrial appendage (LAA) during the operation and fasting blood samples on the same day of LAAC and 45 days after discharge. The biochemical indicators, thrombin-antithrombin complex (TAT), soluble P-selectin (sP-selectin), von Willebrand factor (vWF), and CD40 ligand (CD40L), were measured by enzyme-linked immunosorbent assay. The primary endpoints of this study were the efficacy and safety characteristics of different antithrombotic strategies, including DRT incidence, stroke or transient ischemic attack, systemic embolism, and clinical major and nonmajor bleeding complications during the follow-up of 180 days. The results revealed that TAT, vWF, sP-selectin, and CD40L levels in vein were significantly reduced by 2.4% (p = 0.043), 5.0% (p < 0.001), 8.7% (p < 0.001), and 2.5% (p = 0.043) from their baseline levels after rivaroxaban treatment. Conversely, no significant changes were detected in the dabigatran group. Furthermore, the plasma levels of platelet activation biomarkers (CD40L and sP-selectin) in both LA and LAA groups were significantly lower after anticoagulation with rivaroxaban, as compared to dabigatran treatment (CD40L: 554.62 ± 155.54 vs. 445.02 ± 130.04 for LA p = 0.0013, 578.51 ± 156.28 vs. 480.13 ± 164.37 for LAA p = 0.0052; sP-selectin: 2849.07 ± 846.69 vs. 2225.54 ± 799.96 for LA p = 0.0105, 2915.52 ± 1402.40 vs. 2203.41 ± 1061.67 for LAA p = 0.0022). Notably, the present study suggests that rivaroxaban may be more effective in the prevention of DRT for patients undergoing LAAC.

The Effect of Levetiracetam Compared with Enzyme-Inducing Antiseizure Medications on Apixaban and Rivaroxaban Peak Plasma Concentrations.

BACKGROUND AND OBJECTIVE: Post-stroke epilepsy represents an important clinical challenge as it often requires both treatment with direct oral anticoagulants (DOACs) and antiseizure medications (ASMs). Levetiracetam (LEV), an ASM not known to induce metabolizing enzymes, has been suggested as a safer alternative to enzyme-inducing (EI)-ASMs in patients treated with DOACs; however, current clinical guidelines suggest caution when LEV is used with DOACs because of possible P-glycoprotein induction and competition (based on preclinical studies). We investigated whether LEV affects apixaban and rivaroxaban concentrations compared with two control groups: (a) patients treated with EI-ASMs and (b) patients not treated with any ASM. METHODS: In this retrospective observational study, we monitored apixaban and rivaroxaban peak plasma concentrations (Cmax) in 203 patients treated with LEV (n = 28) and with EI-ASM (n = 33), and in patients not treated with any ASM (n = 142). Enzyme-inducing ASMs included carbamazepine, phenytoin, phenobarbital, primidone, and oxcarbazepine. We collected clinical and laboratory data for analysis, and DOAC Cmax of patients taking LEV were compared with the other two groups. RESULTS: In 203 patients, 55% were female and the mean age was 78 ± 0.8 years. One hundred and eighty-six patients received apixaban and 17 patients received rivaroxaban. The proportion of patients with DOAC Cmax below their therapeutic range was 7.1% in the LEV group, 10.6% in the non-ASM group, and 36.4% in the EI-ASM group (p < 0.001). The odds of having DOAC Cmax below the therapeutic range (compared with control groups) was not significantly different in patients taking LEV (adjusted odds ratio 0.70, 95% confidence interval 0.19-2.67, p = 0.61), but it was 12.7-fold higher in patients taking EI-ASM (p < 0.001). In an analysis in patients treated with apixaban, there was no difference in apixaban Cmax between patients treated with LEV and non-ASM controls, and LEV clinical use was not associated with variability in apixaban Cmax in a multivariate linear regression. CONCLUSIONS: In this study, we show that unlike EI-ASMs, LEV clinical use was not significantly associated with lower apixaban Cmax and was similar to that in patients not treated with any ASM. Our findings suggest that the combination of LEV with apixaban and rivaroxaban may not be associated with decreased apixaban and rivaroxaban Cmax. Therefore, prospective controlled studies are required to examine the possible non-pharmacokinetic mechanism of the effect of the LEV-apixaban or LEV-rivaroxaban combination on patients' outcomes.

Comparative effectiveness of factor Xa non-vitamin K antagonist oral anticoagulants versus phenprocoumon in patients with non-valvular atrial fibrillation.

BACKGROUND: Non-vitamin K antagonist oral anticoagulants (NOACs) have largely supplanted vitamin K antagonists (VKAs) for oral anticoagulation in non-valvular atrial fibrillation (NVAF). However, data on the real-world effectiveness of NOACs vs. phenprocoumon, a VKA widely used in Germany, are limited. The RELOADED study aimed to compare effectiveness of factor Xa NOACs and phenprocoumon in NVAF in clinical practice. METHODS: Patients who started on a factor Xa NOAC or phenprocoumon for NVAF during the study period were enrolled from the Institute for Applied Healthcare Research Berlin. Patients were followed from first prescription until the end of exposure or available data. Primary outcomes were analyzed by Cox proportional hazard regression models and included ischemic stroke and systemic embolism for effectiveness, and intracranial hemorrhage (ICH) for safety. Subgroups of interest were patients with diabetes and patients with renal impairment. RESULTS: The total study population was 64,920; 36.3% of patients initiated phenprocoumon, 34.4% initiated rivaroxaban, 25.0% apixaban, and 4.4% edoxaban. Treatment with phenprocoumon is associated with a similar risk of ischemic stroke/systemic embolism as treatment with rivaroxaban or apixaban; while rivaroxaban (adjusted hazard ratio [HR] 0.57, 95% confidence interval [CI] 0.43-0.75) and apixaban (adjusted HR 0.43, 95% CI 0.31-0.6) were associated with a lower risk of ICH compared to phenprocoumon in NVAF patients. The use of rivaroxaban and apixaban was associated with a lower risk of developing kidney failure in patients with diabetes or renal impairment in comparison to those treated with phenprocoumon. CONCLUSION: The factor Xa NOACs rivaroxaban and apixaban demonstrated similar effectiveness and lower rates of ICH compared with phenprocoumon in this study.

Real-world experience of direct oral anticoagulant use in a single pediatric center.

BACKGROUND: Pediatric venous thromboembolism has increased by 130%-200%, specifically in hospitalized children, and direct oral anticoagulants (DOACs) offer several therapeutic advantages. METHODS: This study aims to evaluate the real-world epidemiological and outcome data from a retrospective review of pediatric patients treated with DOACs from January 1, 2013 to December 31, 2022. In this single-center, IRB-approved study, 65 patients were identified and analyzed using SPSS statistical software, and a descriptive statistical analysis was conducted. RESULTS: Of the 65 patients, 37% were on apixaban, 61.5% were on rivaroxaban, and 1.5% were on dabigatran. Per the 2023 ISTH outcome definitions, one (2%) patient had a major bleeding episode, six (9%) had clinically relevant non-major bleeding, three (5%) patients had patient-important heavy menstrual bleeding (HMB), and one (1.5%) patient had minor bleeding. Seven (19%) of 37 postmenarchal patients had evidence of HMB. Six (9.2%) patients had recurrent venous thromboembolism while on a DOAC (one was on apixaban, and five were on rivaroxaban) and were transitioned to other forms of anticoagulation. CONCLUSION: Thus, bleeding rates after DOAC therapy are comparable to previous DOAC trials, as well as other anticoagulants in pediatrics. HMB is an important outcome measure and should continue to be investigated. This study reports a higher rate of recurrent thrombosis (9.2%) compared to other trials. However, this observation may be attributed to patients who had ongoing risk factors, as well as a longer duration of study follow-up. Additional multicentered outcome studies evaluating DOAC use in children are needed to determine long-term recurrence and HMB risks.

Dabigatran for Treatment and Secondary Prevention of Venous Thromboembolism in Pediatric Congenital Heart Disease.

BACKGROUND: Congenital heart disease (CHD) is common in children and associated with greater risk of thrombotic complications. Management of these complications with standard-of-care treatment is suboptimal for these children. METHODS AND RESULTS: The effectiveness and safety of dabigatran were demonstrated in pivotal pediatric studies for the treatment of acute venous thromboembolism (VTE; NCT01895777) and secondary VTE prevention (NCT02197416). We report safety and efficacy outcomes from subgroup analyses of these studies for children with CHD (diagnosed according to local practice) and those without. In NCT01895777, 17/21 (81.0%) and 16/27 (59.3%) patients with CHD (including cyanotic) treated with dabigatran and standard of care, respectively, met the primary end point (complete thrombus resolution, freedom from recurrent VTE, and freedom from VTE-related death; odds ratio [OR], 0.34 [95% CI, 0.08-1.23]). In patients without CHD, 41.0% (n=64) versus 34.9% (n=22) achieved this end point with the respective treatments (OR, 0.77 [95% CI, 0.42-1.41]). Although numerical differences were observed, no heterogeneity in treatment effect of dabigatran on the composite primary end point was detected in patients with and without CHD (interaction P =0.2674). In NCT02197416, recurrent VTE at 12 months occurred in 0/17 patients with CHD versus 3/194 (1.5%) without. No patient with CHD experienced major or clinically relevant nonmajor bleeding events. CONCLUSIONS: Data on favorable anticoagulant alternatives for the unmet needs of children with CHD are emerging, and our exploratory results suggest that dabigatran could be an appropriate treatment choice, although challenging sample size limitations in pediatric studies require cautious interpretation of findings. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01895777, NCT02197416.

Direct oral anticoagulants in trauma patients.

PURPOSE OF REVIEW: Direct oral anticoagulants (DOACs) are increasingly prescribed for prevention of thromboembolic events. Thus, trauma care providers are facing a steadily raising number of injured patients on DOACs. RECENT FINDINGS: Despite a predictable pharmacokinetic profile, the resulting plasma levels of trauma patients upon admission and bleeding risks remain uncertain. Therefore, recent guidelines recommend the measurement of DOAC plasma concentrations in injured patients. Alternatively, DOAC specific visco-elastic tests assays can be applied to identify DOAC patients at bleeding risk.Bleeding complications in trauma patients on DOACs are generally higher compared to nonanticoagulated subjects, but comparable to vitamin K antagonists (VKAs). In particular, a traumatic brain injury does not carry an increased risk of intracranial bleeding due to a DOAK intake compared to VKAs. Current studies demonstrated that up to 14% of patients with a hip fracture are on DOACs prior to surgery. However, the majority can be operated safely within a 24h time window without an increased bleeding rate.Specific antagonists facilitate rapid reversal of patients on DOACs. Idarucizumab for dabigatran, and andexanet alfa for apixaban and rivaroxaban have been approved for life threatening bleeding. Alternatively, prothrombin complex concentrate can be used. Dialysis is a potential treatment option for dabigatran and haemoabsorption with special filters can be applied in patients on FXa-inhibitors. SUMMARY: Current guidelines recommend the measurement of DOAC plasma levels in trauma patients. Compared to VKAs, DOACs do not carry a higher bleeding risk. DOAC specific antagonists facilitate the individual bleeding management.

Age-related variation in coagulation factors in non-valvular atrial fibrillation patients receiving direct oral anticoagulants.

Age is a significant risk factor for ischemic stroke. However, the influence of aging on coagulation parameters in non-valvular atrial fibrillation (NVAF) patients treated with direct oral anticoagulants (DOACs) remains unclear. A total of 775 samples were collected from 224 NVAF patients receiving apixaban, edoxaban or rivaroxaban. The samples were categorized into three age groups: (i) ≤ 64 years, (ii) 65-74 years, and (iii) ≥ 75 years (apixaban: N = 48, 108, 119; edoxaban: N = 63, 68, 126; rivaroxaban: N = 115, 90, 38, respectively). Coagulation parameters including fibrinogen (Fbg), factor II, factor V, factor VII, factor X, and D-dimer, were compared between the three age groups for each drug. The slopes in the correlation between drug concentrations and modified diluted prothrombin time (mdPT) were also assessed. Fbg and factor V increased with age, while factor II and factor X decreased. Factor VII and D-dimer showed no significant differences across age categories. The slope in response to drug concentrations was similar between the age groups. In NVAF patients treated with apixaban, edoxaban and rivaroxaban, some coagulation parameters exhibited age-related variation. However, the response of mdPT to drug concentration was consistent across age categories.

Exploring the level of agreement among different drug-drug interaction checkers: a comparative study on direct oral anticoagulants.

BACKGROUND: Direct oral anticoagulants (DOACs) may be involved in drug-drug interactions (DDIs) potentially increasing the risk of adverse drug reactions. This study aimed to evaluate the level of agreement among interaction checkers (ICs) and DOACs' summary of product characteristics (SPCs), in listing DDIs and in attributing DDIs' severity. RESEARCH DESIGN AND METHODS: The level of agreement among five ICs (i.e. INTERCheck WEB, Micromedex, Lexicomp, Epocrates, and drugs.com) in identifying potential DDIs and in attributing severity categories was evaluated using Gwet's AC1 on all five ICs and by comparing groups of four- and two-pair sets of ICs. RESULTS: A total of 486 potentially interacting drugs with dabigatran, 556 for apixaban, 444 for edoxaban, and 561 for rivaroxaban were reported. The level of agreement among the ICs in identifying potential DDIs was poor (range: 0.12-0.16). Similarly, it was low in 4 and 2 sets analyses. The level of agreement among the ICs in classifying the severity of potential DDIs was poor (range: 0.32-0.34), also in 4 and 2 sets analyses. CONCLUSIONS: The heterogeneity among different ICs and SPCs underscores the need to standardize DDI datasets and to conduct real-world studies to generate evidence regarding the frequency and clinical relevance of potential DOAC-related DDIs.

Mortality after major bleeding in Asian atrial fibrillation patients receiving different direct oral anticoagulants: a nationwide, propensity score study.

In this research, we assessed mortality after major bleeding events in atrial fibrillation (AF) patients taking four direct oral anticoagulants (DOACs). Drawing data from the Taiwan National Health Insurance Research Database between 2016 and 2019, we focused on AF patients on DOACs who had major bleeding episodes. Using propensity score stabilized weighting, we established four comparable pseudo-DOAC groups. Among 2770 patients (460 dabigatran, 1322 rivaroxaban, 548 apixaban, 440 edoxaban), 85.3% were prescribed low-dose regimens. The 7-day mortality rate was 9.0%, surging to 16.0% by the 30th day. Compared with dabigatran, there was a distinct divergence in 7-day mortality of factor Xa inhibitors (p = 0.012), with hazard ratios of 1.83 (95% CI 1.11-3.00, p = 0.017) for rivaroxaban, 2.13 (95% CI 1.23-3.66, p = 0.007) for apixaban, and 2.41 (95% CI 1.39-4.19, p = 0.002) for edoxaban. This pattern remained consistent when analyzing the subgroup that received lower dosages of DOACs. In conclusion, factor Xa inhibitors were associated with a significantly higher risk of 7-day mortality following major bleeding events than dabigatran among AF patients.

Dispensing pharmacy chains and direct anticoagulants: Potential associations with patient outcomes.

PURPOSE: Pharmacy chains can differ with respect to the characteristics of their patient populations as well as their nonprescription products, services, and practices, and thus may serve as a surrogate for potential unmeasured confounding in observational studies of prescription drugs. This study evaluates whether a single-source drug can have different patient outcomes based on the dispensing pharmacy chain. METHODS: Separate analyses for two anticoagulant drugs, rivaroxaban and apixaban, were conducted using Medicare Fee-for-Service claims evaluating the association between dispensing pharmacy chain and outcomes of acute myocardial infarction, ischemic stroke, intracranial hemorrhage, gastrointestinal (GI) bleeding, all-cause mortality, and major GI bleeding. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates across pharmacy chain cohorts, and outcome association was assessed with a Cox Proportional Hazards model. RESULTS: We observed no differences in outcomes across pharmacy chains for apixaban recipients. Rivaroxaban recipients from pharmacy chain C, however, had lower rates of GI bleeding (adjusted HR 0.83; 95% CI 0.69-1.00) and ischemic stroke (adjusted HR 0.57; 95% CI 0.38-0.87) as compared to chain A in primary analyses with a 3-day grace period. The results moved closer to the null when 14- and 30-day grace periods were implemented. CONCLUSIONS: These results suggest that dispensing pharmacy chains may have the potential to act as a confounder of associations between drug exposure and outcome in some observational studies. Additional studies of potential confounding by pharmacy chain are needed. Further evaluation of potential pharmacy chain effects on safe use would be of value.

Dabigatran-related serious medication errors: an analysis using data from VigiBase.

OBJECTIVE: To analyze the serious medication errors (MEs) on dabigatran, and their related factors, in order to avoid or reduce the occurrence of adverse events. METHODS: Serious MEs related to dabigatran were extracted from the WHO global database of reported potential side effects of medicinal products (VigiBase) by using "Medication errors and other product use errors and issues" High Level Group Term (HLGT) of the international Medical Dictionary for Regulatory Activities (MedDRA). Well-documented reports, vigiGrade completeness score ≥ 0.80, or with an informative narrative were analyzed with a focus on the clinical features of the cases. The PCNE Classification for drug-related problems (DRP) was used to classify medication errors in our analysis of cases. RESULTS: Until January 26, 2020, there were 453 cases with serious MEs related to dabigatran in VigiBase, and 113 were well-documented. Among these, 69 patients (61%) were hospitalized or had prolonged hospitalization, 16 (14%) had life-threatening events, and 12 (11%) died. The MEs occurred in the prescription phase in 77 cases, in administration in 35, and at the dispensing stage in one case. The MEs in prescription were related to a drug selection error in 44 cases (24 concerning contraindications and 20 drug interactions) and to dose error in 33 cases (17 with excessive dose; eight with insufficient frequency; four had an incorrect time; in three, the dose was too low; and in one, too frequent). The MEs in administration were medical-staff-related errors in five cases (three with wrong administration route, one administration omission, and one overdose), patient-related errors in 28 (14 insufficient dose or no administration, seven improper drug storage, four wrong administration method, and three over prescribed dose), and other errors in two (without efficacy monitoring). The dispensing error of a wrong drug strength occurred in a pharmacy. The main adverse events in the 113 patients were haemorrhage in 57 cases (50%) and ischemia in 29 cases (26%). CONCLUSION: Based on the analysis of reports in VigiBase, serious MEs related to dabigatran mainly occurred during prescription and administration. Although the incidence of MEs with clinical consequences in the use of dabigatran cannot be determined, attention should be paid to selection of the appropriate dose to a right patient in the prescription, and to patient compliance and storage in drug administration. The patient harm mainly manifested itself as bleeding or ischemia including fatal outcome in rare patients.

Non-vitamin-K-antagonist oral anticoagulants (NOACs) after acute myocardial infarction: a network meta-analysis.

BACKGROUND: Balancing the risk of bleeding and thrombosis after acute myocardial infarction (AMI) is challenging, and the optimal antithrombotic therapy remains uncertain. The potential of non-vitamin K antagonist oral anticoagulants (NOACs) to prevent ischaemic cardiovascular events is promising, but the evidence remains limited. OBJECTIVES: To evaluate the efficacy and safety of non-vitamin-K-antagonist oral anticoagulants (NOACs) in addition to background antiplatelet therapy, compared with placebo, antiplatelet therapy, or both, after acute myocardial infarction (AMI) in people without an indication for anticoagulation (i.e. atrial fibrillation or venous thromboembolism). SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, the Conference Proceedings Citation Index - Science, and two clinical trial registers in September 2022 with no language restrictions. We checked the reference lists of included studies for any additional trials. SELECTION CRITERIA: We searched for randomised controlled trials (RCTs) that evaluated NOACs plus antiplatelet therapy versus placebo, antiplatelet therapy, or both, in people without an indication for anticoagulation after an AMI. DATA COLLECTION AND ANALYSIS: Two review authors independently checked the results of searches to identify relevant studies, assessed each included study, and extracted study data. We conducted random-effects pairwise analyses using Review Manager Web, and network meta-analysis using the R package 'netmeta'. We ranked competing treatments by P scores, which are derived from the P values of all pairwise comparisons and allow ranking of treatments on a continuous 0-to-1 scale. MAIN RESULTS: We identified seven eligible RCTs, including an ongoing trial that we could not include in the analysis. Of the six RCTs involving 33,039 participants, three RCTs compared rivaroxaban with placebo, two RCTs compared apixaban with placebo, and one RCT compared dabigatran with placebo. All participants in the six RCTs received concomitant antiplatelet therapy. The available evidence suggests that rivaroxaban compared with placebo reduces the rate of all-cause mortality (risk ratio (RR) 0.82, 95% confidence interval (CI) 0.69 to 0.98; number needed to treat for an additional beneficial outcome (NNTB) 250; 3 studies, 21,870 participants; high certainty) and probably reduces cardiovascular mortality (RR 0.83, 95% CI 0.69 to 1.01; NNTB 250; 3 studies, 21,870 participants; moderate certainty). There is probably little or no difference between apixaban and placebo in all-cause mortality (RR 1.09, 95% CI 0.88 to 1.35; number needed to treat for an additional harmful outcome (NNTH) 334; 2 studies, 8638 participants; moderate certainty) and cardiovascular mortality (RR 0.99, 95% CI 0.77 to 1.27; number needed to treat not applicable; 2 studies, 8638 participants; moderate certainty). Dabigatran may reduce the rate of all-cause mortality compared with placebo (RR 0.57, 95% CI 0.31 to 1.06; NNTB 63; 1 study, 1861 participants; low certainty). Dabigatran compared with placebo may have little or no effect on cardiovascular mortality, although the point estimate suggests benefit (RR 0.72, 95% CI 0.34 to 1.52; NNTB 143; 1 study, 1861 participants; low certainty). Two of the investigated NOACs were associated with an increased risk of major bleeding compared to placebo: apixaban (RR 2.41, 95% CI 1.44 to 4.06; NNTH 143; 2 studies, 8544 participants; high certainty) and rivaroxaban (RR 3.31, 95% CI 1.12 to 9.77; NNTH 125; 3 studies, 21,870 participants; high certainty). There may be little or no difference between dabigatran and placebo in the risk of major bleeding (RR 1.74, 95% CI 0.22 to 14.12; NNTH 500; 1 study, 1861 participants; low certainty). The results of the network meta-analysis were inconclusive between the different NOACs at all individual doses for all primary outcomes. However, low-certainty evidence suggests that apixaban (combined dose) may be less effective than rivaroxaban and dabigatran for preventing all-cause mortality after AMI in people without an indication for anticoagulation. AUTHORS' CONCLUSIONS: Compared with placebo, rivaroxaban reduces all-cause mortality and probably reduces cardiovascular mortality after AMI in people without an indication for anticoagulation. Dabigatran may reduce the rate of all-cause mortality and may have little or no effect on cardiovascular mortality. There is probably no meaningful difference in the rate of all-cause mortality and cardiovascular mortality between apixaban and placebo. Moreover, we found no meaningful benefit in efficacy outcomes for specific therapy doses of any investigated NOACs following AMI in people without an indication for anticoagulation. Evidence from the included studies suggests that rivaroxaban and apixaban increase the risk of major bleeding compared with placebo. There may be little or no difference between dabigatran and placebo in the risk of major bleeding. Network meta-analysis did not show any superiority of one NOAC over another for our prespecified primary outcomes. Although the evidence suggests that NOACs reduce mortality, the effect size or impact is small; moreover, NOACs may increase major bleeding. Head-to-head trials, comparing NOACs against each other, are required to provide more solid evidence.

A rapid and sensitive analytical methodology for the simultaneous biomonitoring of two direct oral anticoagulant drugs and their major metabolites in thromboembolic disordered patients samples for clinical evaluations.

Apixaban and dabigatran are the two major direct oral anticoagulant drugs to treat thromboembolic disordered patients. Increasing the clinical application for the thromboembolic disorder and monitoring the concentrations of apixaban, dabigatran, and their metabolites are essential in most clinical circumstances. In this work, we developed a rapid analytical methodology comprising of vortex-assisted salt-enhanced liquid-liquid microextraction technique coupled with UHPLC-MS/MS for the extraction and simultaneous determination of two major direct oral anticoagulant drugs (apixaban, dabigatran), and their two major metabolites from plasma, serum, and urine samples of patients. The developed method was optimized with various procedural steps and validated to study the analytical merits. The developed method yielded a good detection limit of 0.01 ∼ 0.37 ng/mL, 0.01 ∼ 0.32 ng/ml, and 0.01 ∼ 0.27 ng/mL for four target analytes in the plasma, serum, and urine matrices. Moreover, extraction recoveries ranged from 85.11 - 113.57% (for plasma), 89.63 - 110.47% (for serum), and 87.44 -106.79% (for urine samples) with 8.78% RSD. In addition, the method exhibited good R2 values of 0.999 for all four target analytes, and the specificity and carryover study revealed no carryover effect from the UHPLC-MS/MS system for determining the apixaban, dabigatran, and their metabolites. Due to the above advantages, the developed analytical technique was applied to examine 11 real-time clinical patients' samples, and the observed results were satisfactory for all three different sample matrices. Therefore, this analytical method can be applied for biomonitoring apixaban, dabigatran, and their two major metabolites with high sensitivity in a short time for various clinical applications.

Antithrombotic Usage, Including Three-Year Outcomes With Dabigatran and Vitamin K Antagonists for Atrial Fibrillation, in Eastern Europe: A Descriptive Analysis From Phase 3 of the GLORIA-AF Registry.

BACKGROUND: Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF) is a prospective registry of outcomes from patients with newly diagnosed AF at risk of stroke. In the propensity score (PS)-matched global population of phase 3 GLORIA-AF, at 3 years, dabigatran-treated patients experienced reduced risk for major bleeding, and similar risk for stroke and myocardial infarction, compared with vitamin K antagonist (VKA)-treated patients. STUDY QUESTION: Do patients in Eastern Europe benefit from treatment with dabigatran versus VKA? STUDY DESIGN: Descriptive analysis, without PS matching. To contextualize the Eastern Europe results of GLORIA-AF phase 3, we also descriptively analyzed the global population without PS matching. Consecutive patients with newly diagnosed AF and CHA2DS2-VASc-score ≥1 were enrolled until December 2016 in 38 countries (9 in Eastern Europe). MEASURES AND OUTCOMES: Three-year outcomes with dabigatran and VKA. RESULTS: In Eastern Europe, 1341 patients were eligible (6% of patients globally), and incidence rates (per 100 patient-years) for the following outcomes were numerically lower with dabigatran (N = 498) versus VKA (N = 466): major bleeding (0.26 vs. 0.90), all-cause death (2.04 vs. 3.50), and a composite of stroke, systemic embolism, myocardial infarction, life-threatening bleeding, and vascular death (1.37 vs. 1.92); stroke was comparable (0.51 vs. 0.50). All incidence rates were numerically lower in Eastern Europe versus the global population for both treatments. Chronic concomitant use of high bleeding risk medications (eg, nonsteroidal anti-inflammatories) was lower in Eastern Europe (dabigatran 3.8%, VKA 9.3%) than globally (dabigatran 14.8%, VKA 20.6%) and persistence with dabigatran was higher in Eastern Europe (76%) than globally (64%). CONCLUSIONS: Dabigatran was associated with numerically reduced major bleeding, all-cause death, and cardiovascular (CV) composite, with comparable risk of stroke versus VKA, in Eastern Europe. Limitations of this descriptive analysis include few CV events (n = 11 for stroke, in the dabigatran and VKA groups combined) and a lack of statistical analysis and PS matching, which precludes definitive conclusions; however, the CV outcomes in Eastern Europe were consistent with the beneficial impact of dabigatran versus VKA in the statistically analyzed global population with PS matching.