Efficacy and safety of dabigatran and rivaroxaban in atrial fibrillation patients with impaired liver function: a multicenter retrospective cohort study.

BACKGROUND: The efficacy and safety of direct oral anticoagulants (DOACs) in atrial fibrillation (AF) patients with impaired liver function (ILF) have not been sufficiently studied. The aim of this study was to evaluate the efficacy and safety of DOACs for stroke prevention in patients with AF and ILF. METHOD: This study was based on data from 15 centers in China, including 4,982 AF patients. The patients were divided into 2 subgroups based on their liver function status: patients with normal liver function (NLF)(n = 4213) and patients with ILF (n = 769). Logistic regression analysis was used to investigate the risk of total bleeding, major bleeding, thromboembolism, and all-cause deaths in AF patients with NLF and ILF after taking dabigatran or rivaroxaban, respectively. RESULTS: Among AF patients treated with dabigatran or rivaroxaban, patients with ILF were associated with significantly higher major bleeding, compared with NLF patients (aOR: 4.797; 95% CI: 2.224-10.256; P < 0.001). In patients with NLF, dabigatran (n = 2011) had considerably lower risk of total bleeding than rivaroxaban (n = 2202) (aOR: 1.23; 95% CI: 1.002-1.513; P = 0.049). In patients with ILF, dabigatran (n = 321) significantly favored lower risks of major bleeding compared with rivaroxaban(n = 448) (aOR: 5.484; 95% CI: 1.508-35.269; P = 0.026). CONCLUSION: After using dabigatran or rivaroxaban, patients with ILF had remarkably increased risk of major bleeding compared with patients with NLF. In AF patients with NLF, dabigatran had the distinct strength of significantly reduced risk of total bleeding compared with rivaroxaban. In patients with AF and ILF, dabigatran use was associated with lower risk for major bleeding compared with rivaroxaban.

A new model to predict the risk of major gastrointestinal bleeding in patients on direct oral anticoagulants (dabigatran and rivaroxaban).

AIMS: The aim of this study was to identify factors associated with gastrointestinal bleeding (GIB) in patients on direct oral anticoagulants (DOACs) and develop a risk score that would provide an effective tool for the clinical assessment of GIB. METHODS: This was a multicentre retrospective analysis of clinical and follow-up data of patients treated with DOACs. The score was developed through logistic regression. The performance of score was evaluated using the area under the receiver operating characteristic curve (AUC), sensitivity, specificity and Hosmer-Lemeshow test. RESULTS: The 11 903 patients had a mean age of 65.1 years. In multivariate analysis, age ≥65 years, alcohol use, history of peptic ulcer, history of major bleeding, abnormal liver function or renal function, cancer, platelet count <100 × 109 /L, anaemia, and concurrent antiplatelet agent or non-steroidal anti-inflammatory drug treatment were independent risk factors for GIB, and concurrent treatment with gastrointestinal protective agents were a protective factor. The Alfalfa-DOAC-GIB score was constructed using these 12 factors. The AUC of the Alfalfa-DOAC-GIB score was 0.77 (95% CI 0.74-0.81), which was higher than that of the HAS-BLED score (0.69; 95% CI 0.65-0.72) and the New score (0.65; 95% CI 0.61-0.68). CONCLUSIONS: Based on 12 factors, we developed a gastrointestinal bleeding risk score. The newly developed Alfalfa-DOAC-GIB score has better predictive value than the HAS-BLED score and the New score, and might be an effective tool to help reduce the occurrence of GIB in patients using DOACs.

Safety and efficacy of direct oral anticoagulation in patients with and without radiofrequency ablation of non-valvular atrial fibrillation: a multicenter retrospective cohort study.

BACKGROUND: Based on the few available studies on the prognostic benefit of using direct oral anticoagulants (DOACs) after atrial fibrillation (AF) ablation. Therefore, this study aimed to evaluate the prognostic differences between patients who underwent radiofrequency ablation (RFA) and those without RFA taking DOACs. METHODS: This is a multicenter retrospective cohort study enrolling 6137 patients with non-valvular AF (NVAF) at 15 hospitals in China. Patient information was collected through a mean follow-up of 10 months and medical record queries. Clinical outcomes included major bleeding, total bleeding, thrombosis, all-cause death, and a composite endpoint of bleeding, thrombosis, and all-cause death. RESULTS: After adjusting for confounders and propensity score matching (PSM), patients with RFA of NVAF had a significantly lower risk of major bleeding [OR 0.278 (95% CI, 0.150-0.515), P<0.001], thrombosis [OR 0.535 (95% CI, 0.316-0.908), P=0.020] and the composite endpoint [ OR 0.835 (95% CI, 0.710-0.982), P=0.029]. In the RFA PSM cohort, dabigatran was associated with reduced all-cause death in patients with RFA of NVAF [OR 0.420 (95% CI, 0.212-0.831), P=0.010]. In the no RFA PSM cohort, rivaroxaban was associated with a reduction in major bleeding [OR 0.521 (95% CI, 0.403-0.673), P<0.001], total bleeding [OR 0.114 (95% CI, 0.049-0.266), P<0.001], and the composite endpoint [OR 0.659 ( 95% CI, 0.535-0.811), P<0.001]. CONCLUSION: Among patients with NVAF treated with DOACs, RFA was a negative correlate of major bleeding, thrombosis, and composite endpoints but was not associated with total bleeding or all-cause mortality.

Safety and efficacy of direct oral anticoagulants in stroke prevention in patients with atrial fibrillation complicated with anemia and/or thrombocytopenia: a retrospective cohort study.

BACKGROUND: There are limited data about the clinical benefits and harm of direct oral anticoagulants (DOACs) in stroke prevention in patients with atrial fibrillation (AF) complicated with anemia or thrombocytopenia. METHODS: This is a multi-center retrospective cohort study involving 5469 AF patients from 15 hospitals in China. Patients were divided into three groups according to hemoglobin and platelet levels: Group 1 (hemoglobin male ≥ 130 g/L; female ≥ 120 g/L and platelet ≥ 100 × 109/L), Group 2 (hemoglobin male < 130 g/L; female < 120 g/L or platelet < 100 × 109/L), and Group 3 (hemoglobin male < 130 g/L; female < 120 g/L and platelet < 100 × 109/L). Patients in each category are further divided into two groups according to their stroke prevention strategies: rivaroxaban or dabigatran. Clinical results include major, minor, total bleeding, thrombosis, and the composite outcome of major bleeding and thrombosis. RESULTS: Higher hemoglobin levels were associated with a reduced risk of total bleeding and major bleeding, while platelet counts were not associated with any event. Compared with Group 1, Group 2 had a higher risk of major bleeding (aOR 1.70, 95%CI 1.12-2.57, P = 0.012), and the composite endpoint of major bleeding and thrombosis (aOR 1.70, 95%CI 1.19-2.44, P = 0.004). Compared with Group 1, Group 3 had a higher total bleeding risk (aOR 2.15, 95%CI 1.14-4.05, P = 0.018). Compared with dabigatran, rivaroxaban was associated with higher composite risk in Group 1 (aOR 2.91, 95% CI 1.66-5.16, P < 0.001) and Group 2 (aOR 3.05, 95%CI 1.46-6.39, P = 0.003), but there was no significant difference in Group 3 (aOR 1.78, 95%CI 0.23-13.54, P = 0.577). CONCLUSIONS: Higher hemoglobin levels are associated with a reduced risk of total bleeding and major bleeding in patients with AF. Dabigatran was associated with better clinical outcomes than rivaroxaban in patients with anemia or thrombocytopenia but not in those with anemia and thrombocytopenia.

Association between Body Mass Index and Clinical Outcomes in Patients with Non-valvular Atrial Fibrillation Receiving Direct Oral Anticoagulants: A New Piece of Evidence on the Obesity Paradox from China.

PURPOSE: We conducted a multicenter real-world study in China to assess the association between body mass index (BMI) and clinical outcomes in patients with atrial fibrillation (AF) taking direct oral anticoagulants (DOACs). METHOD: This is a retrospective multicenter cohort study conducted in 15 centers in China. We collected demographic information through the hospital information system and obtained clinical events through follow-up visits to patients or relatives. Clinical outcomes include major, minor, total bleeding, thromboembolism, and all-cause death. RESULT: A total of 6164 patients with non-valvular AF (NVAF) were included in this study. The incidence of major bleeding in patients with NVAF differed significantly by BMI category (P < 0.001), with 5.2% in the underweight group, 2.6% in the normal group, 1.4% in the overweight group, 1.1% in the obese I group, and 1.3% in the obese II group. There was no significant difference in minor, total bleeding, and thrombosis in the five groups (P = 0.493; P = 0.172; P = 0.663). All-cause death was significantly different among the five groups (P < 0.001), with 8.9% in the underweight group, 6.3% in the normal group, 4.8% in the overweight group, 2.2% in the obese I group, and 0.4% in the obese II group. High BMI was negatively associated with major bleeding (OR = 0.353, 95% CI 0.205-0.608), total bleeding (OR = 0.664, 95% CI 0.445-0.991), and all-cause death (OR = 0.370, 95% CI 0.260-0.527). CONCLUSION: In patients with NVAF treated with DOACs, higher BMI was associated with lower major bleeding and better survival. BMI was a negative correlate of total bleeding, but not minor bleeding and thrombosis.

To establish a model for the prediction of initial standard and maintenance doses of warfarin for the Han Chinese population based on gene polymorphism: a multicenter study.

PURPOSE: The purpose of this paper is to study the correlation between demographic and clinical factors and warfarin dose of patients in Chinese Han population taking warfarin and study gene polymorphisms impact of related gene loci (CYP2C9*3, VKORC1-1639G > A) on warfarin doses, to establish a model to predict initial standard dose and maintenance dose based on CYP2C9*3, VKORC1-1639G > A genotype. METHODS: The study collects the data of patients in our hospital and other subcenters which incorporates 2160 patients to establish the initial dose model and 1698 patients for the stable dose model, and sequences 26 multigene sites in 451 patients. Based on the patient's dosage, clinical data, and demographic characteristics, the genetic and non-genetic effects on the initial dose and stable dose of warfarin are calculated by using statistical methods, and the prediction model of initial standard dose and maintenance dose can be established via multiple linear regression. RESULTS: The initial dose of warfarin (mg/day) was calculated as (1.346 + 0.350 × (VKORC1-1639G > A) - 0.273 × (CYP2C9*3) + 0.245 × (body surface area) - 0.003 × (age) - 0.036 × (amine-iodine) + 0.021 × (sex))2. This model incorporated seven factors and explained 55.3% of the individualization differences of the warfarin drug dose. The maintenance dose of warfarin (mg/day) was calculated as (1.336 + 0.299 × (VKORC1-1639G > A) + 0.480 × (body surface area) - 0.214 × (CYP2C9*3) - 0.074 × (amine-iodine) - 0.003 × (age) - 0.077 × (statins) - 0.002 × (height))2. This model incorporated six factors and explained 42.4% of the individualization differences in the warfarin drug dose. CONCLUSION: The genetic and non-genetic factors affecting warfarin dose in Chinese Han population were studied systematically in this study. The pharmacogenomic dose prediction model constructed in this study can predict anticoagulant efficacy of warfarin and has potential application value in clinical practice.

Off-label dose direct oral anticoagulants and clinical outcomes in Asian patients with atrial fibrillation: A new evidence of Asian dose.

AIM: This study aimed to evaluate the label compliance of DOACs in the Chinese AF population and explore the relationship between inappropriate DOACs dosage and clinical results. METHODS AND RESULTS: This is a retrospective multicenter cohort study conducted in 14 centers in China. According to the China Food and Drug Administration(CFDA) label and the recommendations of international guidelines, we divided patients into on-label dosage and off-label dosage. We then compared the clinical results after propensity score matching. We collect demographic information through the hospital information system and obtain clinical events through follow-up of patients or their families. Clinical results include major, minor, total bleeding, thrombosis, and all-cause death. 4191 patients with non-valvular AF (NVAF) were included, and approximately 55.6% and 1.7% of AF patients received off-label underdose and off-label overdose of DOACs, respectively. Compared with the on-label dose, DOACs with off-label underdose were associated with a significantly reduced risk of major bleeding (P = 0.004, OR = 0.23,95% CI: 0.08-0.69) and all-cause death (P<0.001, OR = 0.49,95% CI: 0.33-0.73). However, there was no significant difference in thrombotic events (P = 0.865 OR = 1.06,95% CI: 0.54-2.07) and minor bleeding (P = 0.465, OR = 1.10,95% CI: 0.85-1.43) risk. CONCLUSIONS: About 57.3% of Asian AF patients received an off-label dose of DOACs in daily practice. Off-label underdose DOACs were associated with significantly lower risks of major bleeding, all-cause death, and similar risks of minor bleeding, thrombotic events compared with on-label dose DOACs. Further prospective randomized trials are needed to determine the optimal dose of DOACs in Asian patients with AF at high bleeding risk.

Efficacy and Safety of Direct Oral Anticoagulants in Patients With Atrial Fibrillation Combined With Hypertension: A Multicenter, Retrospective Cohort Study.

Whether there are differences in direct oral anticoagulants efficacy and safety in patients with atrial fibrillation (AF) combined with hypertension is unclear. We therefore conducted a multicenter retrospective cohort study to assess the differences in the efficacy and safety of direct oral anticoagulants in patients with AF combined with hypertension. This multicenter retrospective cohort study was based on data from 15 centers in China and included 2086 patients with AF. We divided the patients into dabigatran and rivaroxaban groups according to their direct oral anticoagulants. Propensity score matching was used to balance the covariates between the groups. Due to our limited sample size, the number of cases of some clinical events with low incidence was small. During a mean follow-up period of 10 months, a total of 268 (12.9%) bleeding events occurred, including 27 (1.3%) major bleeding events and 241 (11.6%) minor bleeding events, and 45 (2.2%) thromboembolic events. In patients with AF combined with hypertension, rivaroxaban was associated with a higher major bleeding incidence than dabigatran (odds ratio [OR], 2.89 [95% confidence interval [CI, 1.22-6.87]; P = .012). In contrast, the risk of thromboembolism and minor bleeding was similar for rivaroxaban (OR, 0.55 [95%CI, 0.29-1.01]; P = .069) and dabigatran (OR, 0.82 [95%CI, 0.63-1.08]; P = .150). Based on the results of this study, in patients with AF and hypertension treated with direct oral anticoagulants, the incidence of thromboembolism and minor bleeding was not statistically different between dabigatran and rivaroxaban, but compared with rivaroxaban, dabigatran was associated with a lower risk of major bleeding.

New score for predicting thromboembolic events in patients with atrial fibrillation using direct oral anticoagulants.

Determinants of thrombotic events remain uncertain in patients with atrial fibrillation treated with direct oral anticoagulants (DOACs). Our aim was to identify risk factors associated with thromboembolism in patients with at atrial fibrillation on DOACs and to construct and externally validate a predictive model that would provide a validated tool for clinical assessment of thromboembolism. In the development cohort, prediction model was built by logistic regression, the area under the curve (AUC), and Nomogram. External validation and calibration of the model using AUC and Hosmer-Lemeshow test. This national multicenter retrospective study included 3263 patients with atrial fibrillation treated with DOACs. The development cohort consisted of 2390 patients from three centers and the external validation cohort consisted of 873 patients from 13 centers. Multifactorial analysis showed that heavy drinking, hypertension, prior stroke/transient ischemic attack (TIA), cerebral infarction during hospitalization were independent risk factors for thromboembolism. The Alfalfa-TE risk score was constructed using these four factors (AUC = 0.84), and in the external validation cohort, the model showed good discriminatory power (AUC = 0.74) and good calibration (Hosmer-Lemeshow test P value of 0.649). Based on four factors, we derived and externally validated a predictive model for thromboembolism with DOACs in patients with atrial fibrillation (Alfalfa-TE risk score). The model has good predictive value and may be an effective tool to help reduce the occurrence of thromboembolism in patients with DOACs.

New score for predicting major bleeding in patients with atrial fibrillation using direct oral anticoagulants.

PURPOSE: Our aim was to identify factors associated with major bleeding in patients with atrial fibrillation (AF) on direct oral anticoagulants (DOACs) and to construct and externally validate a predictive model that would provide a validated tool for clinical assessment of major bleeding. METHODS: In the development cohort, prediction model was built by logistic regression, the area under the curve (AUC), and Nomogram. External validation, analytical identification and calibration of the model using AUC, calibration curves and Hosmer-Lemeshow test. RESULTS: The development cohort consisted of 4209 patients from 7 centers and the external validation cohort consisted of 1800 patients from 12 centers. Multifactorial analysis showed that age > 65 years, history of bleeding, anemia, vascular disease, antiplatelet therapy/non-steroidal anti-inflammatory drugs and rivaroxaban were independent risk factors for major bleeding, and gastrointestinal protective agents was a protective factor. The Alfalfa-MB model was constructed using these seven factors (AUC = 0.807), and in the external validation cohort, the model showed good discriminatory power (AUC = 0.743) and good calibration (Hosmer-Lemeshow test P value of 0.205). The predictive power of the six bleeding scores was ORBIT (AUC = 0.706), HAS-BLED (AUC = 0.648), ATRIA (AUC = 0.645), HEMORR2 HAGES (AUC = 0.632), ABC (AUC = 0.619) and Shireman (AUC = 0.599) in descending order. CONCLUSION: Based on 7 factors, we derived and externally validated a predictive model for major bleeding with DOACs in patients with AF (Alfalfa-MB). The model has good predictive value and may be an effective tool to help reduce the occurrence of major bleeding in patients with DOACs.

Population Pharmacokinetics of Rivaroxaban in Chinese Patients with Non-Valvular Atrial Fibrillation: A Prospective Multicenter Study.

BACKGROUND AND OBJECTIVE: Rivaroxaban is a novel oral anticoagulant widely used for thromboprophylaxis in patients with non-valvular atrial fibrillation (NVAF). The present study aimed to develop a population pharmacokinetic (PPK) model for rivaroxaban in Chinese patients with NVAF. METHODS: We performed a prospective multicenter study. The plasma concentration of rivaroxaban was directly detected by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and indirectly by rivaroxaban-calibrated chromogenic anti-Xa assay (STA®). Gene polymorphisms were detected by MassARRAY single nucleotide polymorphism genotyping technology. Nonlinear mixed-effects modeling was used to develop the PPK model for rivaroxaban in patients with NVAF, and we simulated the steady-state rivaroxaban exposures under different dosing strategies in different covariate levels. RESULTS: A total of 150 patients from five centers were recruited, including 263 plasma concentrations detected by HPLC-MS/MS, 2626 gene polymorphisms, and 131 plasma concentrations detected by anti-Xa assay. In our study, an oral one-compartment model was used to describe the pharmacokinetics of rivaroxaban in patients with NVAF. In the final model, the estimated apparent clearance (CL/F) and volume of distribution (V/F) were 5.79 L/h (relative standard error [RSE] 4.4%) and 51.5 L (RSE 5.0%), respectively. Covariates in the final model included creatinine clearance, total bilirubin, rs4728709, and body weight. The simulation results showed that in the 15 mg once-daily dosing regimen, in most instances the maximum plasma concentration at steady state (Cmax,ss) and trough plasma concentration at steady state (Cmin,ss) were in the target range for different covariate levels. When patients were administered rivaroxaban 15 or 20 mg once daily, the Cmax,ss and Cmin,ss in the different bodyweight levels were also in the target range. For patients with the ABCB1 rs4728709 mutation, the Cmin,ss in the 10, 15, and 20 mg once-daily dosing regimens were lower than the target range. The anti-Xa assay was highly linearly correlated with the HPLC-MS/MS method [y = 1.014x - 2.4648 (R2 = 0.97)]. CONCLUSIONS: Our study was the first multicenter PPK model for rivaroxaban in Chinese patients with NVAF (Alfalfa-RIVAAF-PPK). The study found that 15 mg once daily may be suitable as the principal rivaroxaban dose for Chinese patients with NVAF. For patients with the rs4728709 mutation, it may be necessary to examine insufficient anticoagulation. We found that the rivaroxaban-calibrated chromogenic anti-Xa assay and HPLC-MS/MS method were highly linearly correlated. Prospective studies with larger sample sizes and real-world studies are needed for further verification.