Rivaroxaban Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation and Severe Kidney Disease or Undergoing Hemodialysis.

BACKGROUND: Patients with nonvalvular atrial fibrillation with stage 4 or 5 chronic kidney disease or undergoing hemodialysis were excluded from phase III randomized trials of nonvitamin K antagonist oral anticoagulants (NOACs). We sought to evaluate the effectiveness and safety of rivaroxaban compared with warfarin in patients with nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis in routine practice. METHODS: Using MarketScan data from January 2012 to December 2017, we identified patients on oral anticoagulant (OAC) with naïve nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis and with ≥12 months of insurance coverage before OAC initiation. Differences in baseline covariates between the rivaroxaban and warfarin cohorts were adjusted using inverse probability-of-treatment weights based on propensity scores calculated using generalized boosted models and 10,000 regression trees (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a stroke/systemic embolism or major bleeding event, OAC discontinuation/switch, insurance disenrollment, or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the OAC cohorts were calculated using Cox regression. RESULTS: We identified 1896 rivaroxaban (38.7% received a dose <20 mg/d) and 4848 warfarin users. Eighty-eight percent of included patients had stage 5 chronic kidney disease or were undergoing hemodialysis. Rivaroxaban did not significantly reduce stroke or systemic embolism (HR = 0.55, 95% CI = 0.27-1.10) or ischemic stroke (HR = 0.67, 95% CI = 0.30-1.50) alone, but it was associated with a significant 32% (95% CI = 1-53%) reduction in major bleeding risk compared with warfarin. CONCLUSION: Among patients with nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis, rivaroxaban appears associated with significantly less major bleeding compared to warfarin.

Effectiveness and safety of rivaroxaban and warfarin for prevention of major adverse cardiovascular or limb events in patients with non-valvular atrial fibrillation and type 2 diabetes.

AIMS: To assess the effectiveness and safety of rivaroxaban versus warfarin for the prevention of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) in patients with type 2 diabetes (T2D) and non-valvular atrial fibrillation (NVAF). MATERIALS AND METHODS: Using MarketScan data from January 2012 to December 2017, we identified oral anticoagulant-naïve patients with NVAF and comorbid T2D and ≥12 months of insurance coverage prior to rivaroxaban or warfarin initiation. Differences in baseline covariates between cohorts were adjusted for using inverse probability of treatment weights based on propensity scores (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a MACE, MALE or major bleeding event, oral anticoagulant discontinuation/switch, insurance disenrolment or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the cohorts were calculated using Cox regression. RESULTS: We identified 10 700 rivaroxaban users (24.1% received a reduced dose) and 13 946 warfarin users. The median (25%, 75% range) age was 70 (62, 79) years, CHA2DS2-VASc score was 4 (3, 5) and duration of available follow-up was 1.4 (0.6, 2.7) years. Eleven percent of patients had peripheral artery disease, 5.1% had coronary artery disease, and 5.1% had a prior MALE, at baseline. Rivaroxaban was associated with a 25% (95% CI 4-41) reduced risk of MACE and a 63% (95% CI 35-79) reduced risk of MALE compared to warfarin. Major bleeding risk did not significantly differ between cohorts (HR 0.95). CONCLUSIONS: Among patients with NVAF and T2D treated in routine practice, rivaroxaban was associated with lower risks of both MACE and MALE versus warfarin, with no significant difference in major bleeding.

Influence of Polypharmacy on the Effectiveness and Safety of Rivaroxaban Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation.

STUDY OBJECTIVE: Patients with nonvalvular atrial fibrillation (NVAF) often have multiple comorbidities requiring concomitant medications in addition to their oral anticoagulant (OAC). The objective of this study was to evaluate the impact of polypharmacy on the effectiveness and safety of rivaroxaban versus warfarin in patients with NVAF managed in routine clinical practice. DESIGN: Retrospective claims analysis. DATA SOURCE: United States Truven MarketScan database (November 2012-March 2017). PATIENTS: Adults who were OAC naïve during the 12 months before the day of the first qualifying rivaroxaban or warfarin dispensing (index date); had at least two International Classification of Diseases, Ninth or Tenth Revision diagnosis codes for atrial fibrillation without codes suggesting valvular heart disease; had at least 12 months of continuous insurance coverage prior to the qualifying OAC dispensing; and were experiencing polypharmacy (concomitant prescription claims for five or more unique chronic medication claims) were included. Patients who had concomitant prescription claims for ≥ 10 unique chronic medication claims constituted the substantial polypharmacy cohort used in the secondary analysis. Patients receiving rivaroxaban were propensity-score matched in a 1:1 ratio to patients receiving warfarin (13,981 patients in each polypharmacy OAC group, and 1765 patients in each substantial polypharmacy OAC group). MEASUREMENTS AND MAIN RESULTS: Patients were followed until occurrence of an event (stroke or systemic embolism [SSE] combined [primary effectiveness outcome] or major bleeding [primary safety outcome]), OAC discontinuation or switch (30-day permissible gap), insurance disenrollment, or end of follow-up period. Rates of SSE, ischemic stroke, and major bleeding were compared by using Cox regression, reported as hazard ratios (HRs) and 95% confidence intervals (CIs). In patients with NVAF taking five or more chronic medications, rivaroxaban was associated with a 34% (95% CI 12-50) and 40% (95% CI 16-57) hazard reduction of SSE and ischemic stroke, respectively. Occurrence of major bleeding was similar between OAC cohorts (HR 1.08, 95% CI 0.92-1.28). A secondary analysis in patients with NVAF with substantial polypharmacy (taking ≥ 10 chronic medications) was also performed. Similar trends in SSE (HR 0.44), ischemic stroke alone (HR 0.62), and major bleeding (HR 1.07) were observed in patients with NVAF who had substantial polypharmacy, although 95% CIs crossed 1.0 for each outcome in this smaller study cohort. CONCLUSION: This real-world study suggests that in the setting of polypharmacy and NVAF, rivaroxaban is an effective and safe alternative to warfarin.

Effectiveness and safety of rivaroxaban vs. warfarin in patients with non-valvular atrial fibrillation and heart failure.

AIMS: Heart failure (HF) is a common co-morbidity in non-valvular atrial fibrillation (NVAF) patients and a potent risk factor for stroke, bleeding, and a decreased time-in-therapeutic range with warfarin. We assessed the real-world effectiveness and safety of rivaroxaban and warfarin in NVAF patients with co-morbid HF. METHODS AND RESULTS: Using US Truven MarketScan Commercial and Medicare supplemental database claims data from 11/2011 to 12/2016, we identified oral anticoagulant (OAC)-naïve NVAF patients with HF (International Classification of Diseases, 10th Revision codes of I50 or I09.81) and ≥12 months of insurance coverage prior to the qualifying OAC dispensing. Rivaroxaban users (20 or 15 mg once daily) were 1:1 propensity score matched to warfarin users, with residual absolute standardized differences <0.1 being achieved for all covariates after matching. Patients were followed up until an event, OAC discontinuation/switch, insurance disenrolment, or end of follow-up. Rates [events per 100 person-years (PYs) of follow-up] for stroke or systemic embolism and major bleeding (using the Cunningham algorithm) were compared between the matched cohorts using Cox proportion hazard regression and reported as hazard ratios (HRs) with 95% confidence intervals (CIs). We matched 3418 rivaroxaban (32% receiving the reduced dose) and 3418 warfarin users with NVAF and HF with a median (interquartile range) available follow-up of 1.4 (0.6, 2.5) years. Median age was 74 (63, 82) years, and median CHA2 DS2 -VASc and HASBLED scores were 4 (3, 5) and 2 (2, 3). Common HF medications included beta-blockers (64%), angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (62%), loop diuretics (46%), digoxin (11%), and aldosterone receptor antagonists (10%). The hazard of developing stroke or systemic embolism (0.98 events/100PY vs. 1.28 events/100PY; HR = 0.82, 95% CI = 0.47-1.44), ischaemic stroke (0.70 events/100PY vs. 1.02 events/100PY; HR = 0.77, 95% CI = 0.41-1.46), or major bleeding (3.86 events/100PY vs. 4.23 events/100PY; HR = 0.98, 95% CI = 0.73-1.31) was not found to be different between rivaroxaban and warfarin users. Intracranial haemorrhage was infrequent in both cohorts and numerically less with rivaroxaban (0.27 events/100PY vs. 0.36 events/100PY; HR = 0.73, 95% CI = 0.25-2.08). CONCLUSIONS: Effectiveness and safety of rivaroxaban vs. warfarin are sustained in NVAF patients with co-morbid HF treated in routine practice. The general consistency between this real-world study and those from phase III randomized trial data of rivaroxaban should provide additional reassurance to clinicians regarding the use of rivaroxaban in NVAF patients with HF.

Effectiveness and safety of rivaroxaban vs. warfarin in non-valvular atrial fibrillation patients with a non-sex-related CHA2DS2-VASc score of 1.

AIMS: To compare the effectiveness and safety of standard-dose rivaroxaban (20 mg o.d.) and warfarin in non-valvular atrial fibrillation (NVAF) patients with a non-sex-related CHA2DS2-VASc score of 1. METHODS AND RESULTS: Analysis of United States Truven MarketScan claims from November 2011 to December 2016 for anticoagulant-naïve NVAF patients with a single non-sex-related stroke risk factor assigned 1-point in the CHA2DS2-VASc score and ≥12-months of continuous medical/prescription insurance coverage prior to the qualifying oral anticoagulant dispensing. Standard-dose rivaroxaban users were 1:1 propensity score-matched to warfarin users. Patients were followed until outcome occurrence, insurance disenrollment, or end of data availability. Primary outcomes included stroke or systemic embolism and major bleeding and were compared using Cox regression and reported as hazard ratios (HRs) with 95% confidence intervals (CIs). In all, 3319 rivaroxaban users were 1:1 propensity score-matched to 3319 warfarin users. Median (interquartile range) duration of follow-up was 1.6 (0.7, 2) years and the most common qualifying stroke risk factor was hypertension (n = 4532, 68.3%). Rivaroxaban was associated with a significant reduction in the 1-year stroke or systemic embolism vs. warfarin (HR 0.41, 95% CI 0.17-0.98), with no significant difference in overall major bleeding (HR 0.74, 95% CI 0.44-1.26) or major bleeding subtypes (HR ranging from 0.33 to 0.78, P > 0.05 for all). Similar results were seen after extending follow-up to 2 years. CONCLUSIONS: Rivaroxaban may lower the rate of stroke or systemic embolism vs. warfarin in NVAF patients with a non-sex-related CHA2DS2-VASc score of 1 without impacting major bleeding.

Effectiveness and Safety of Apixaban, Dabigatran, and Rivaroxaban Versus Warfarin in Frail Patients With Nonvalvular Atrial Fibrillation.

BACKGROUND: Frailty predicts poorer outcomes and decreased anticoagulation use in patients with nonvalvular atrial fibrillation. We sought to assess the effectiveness and safety of apixaban, dabigatran and rivaroxaban versus warfarin in frail nonvalvular atrial fibrillation patients. METHODS AND RESULTS: Using US MarketScan claims data from November 2011 to December 2016, we identified frail oral anticoagulant-naïve nonvalvular atrial fibrillation patients with ≥12 months of continuous insurance coverage before oral anticoagulant initiation. Frailty status was determined using the Johns Hopkins Claims-based Frailty Indicator score (≥0.20 indicating frailty). Users of apixaban, dabigatran, or rivaroxaban were separately 1:1 matched to warfarin users via propensity-scores, with residual absolute standardized differences <0.1 being achieved for all covariates after matching. Patients were followed for up to 2 years or until an event, insurance disenrollment or end of follow-up. Rates of stroke or systemic embolism and major bleeding were compared using Cox regression and reported as hazard ratios (HRs) and 95% confidence intervals (CIs). In total, 2700, 2784, and 5270 patients were included in the apixaban, dabigatran, and rivaroxaban 1:1 matched analyses to warfarin. At 2 years, neither apixaban nor dabigatran were associated with differences in the hazard of stroke or systemic embolism (HR=0.78; 95% CI=0.46-1.35 and HR=0.94; 0.60-1.45) or major bleeding (HR=0.72; 95% CI=0.49-1.06 and HR=0.87; 95% CI=0.63-1.19) versus warfarin. Rivaroxaban was associated with reduced stroke or systemic embolism at 2 years (HR=0.68; 95% CI=0.49-0.95) without significantly altering major bleeding risk (HR=1.07; 95% CI=0.81-1.32). CONCLUSIONS: Our study found rivaroxaban but not apixaban or dabigatran to be associated with reduced SSE versus warfarin in frail nonvalvular atrial fibrillation patients. No direct-acting oral anticoagulants demonstrated a significant difference in major bleeding versus warfarin.

Agreement between coding schemas used to identify bleeding-related hospitalizations in claims analyses of nonvalvular atrial fibrillation patients.

BACKGROUND: Schemas to identify bleeding-related hospitalizations in claims data differ in billing codes used and coding positions allowed. We assessed agreement across bleeding-related hospitalization coding schemas for claims analyses of nonvalvular atrial fibrillation (NVAF) patients on oral anticoagulation (OAC). HYPOTHESIS: We hypothesized that prior coding schemas used to identify bleeding-related hospitalizations in claim database studies would provide varying levels of agreement in incidence rates. METHODS: Within MarketScan data, we identified adults, newly started on OAC for NVAF from January 2012 to June 2015. Billing code schemas developed by Cunningham et al., the US Food and Drug Administration (FDA) Mini-Sentinel program, and Yao et al. were used to identify bleeding-related hospitalizations as a surrogate for major bleeding. Bleeds were subcategorized as intracranial hemorrhage (ICH), gastrointestinal (GI), or other. Schema agreement was assessed by comparing incidence, rates of events/100 person-years (PYs), and Cohen's kappa statistic. RESULTS: We identified 151 738 new-users of OAC with NVAF (CHA2DS2-VASc score = 3, [interquartile range = 2-4] and median HAS-BLED score = 3 [interquartile range = 2-3]). The Cunningham, FDA Mini-Sentinel, and Yao schemas identified any bleeding-related hospitalizations in 1.87% (95% confidence interval [CI]: 1.81-1.94), 2.65% (95% CI: 2.57-2.74), and 4.66% (95% CI: 4.55-4.76) of patients (corresponding rates = 3.45, 4.90, and 8.65 events/100 PYs). Kappa agreement across schemas was weak-to-moderate (κ = 0.47-0.66) for any bleeding hospitalization. Near-perfect agreement (κ = 0.99) was observed with the FDA Mini-Sentinel and Yao schemas for ICH-related hospitalizations, but agreement was weak when comparing Cunningham to FDA Mini-Sentinel or Yao (κ = 0.52-0.53). FDA Mini-Sentinel and Yao agreement was moderate (κ = 0.62) for GI bleeding, but agreement was weak when comparing Cunningham to FDA Mini-Sentinel or Yao (κ = 0.44-0.56). For other bleeds, agreement across schemas was minimal (κ = 0.14-0.38). CONCLUSIONS: We observed varying levels of agreement among 3 bleeding-related hospitalizations schemas in NVAF patients.

IntravenousCorticosteroid Use Is Associated With Reduced Early Recurrence of Atrial Fibrillation Immediately Following Radiofrequency Catheter Ablation.

Background: Early recurrence of atrial fibrillation (ERAF) occurs in up to 40% of patients after radiofrequency catheter ablation for atrial fibrillation (RFCA), increasing hospital stay, need for anti-arrhythmic medications (AADs) and cardioversion, and, possibly, the risk of future AF. It has been postulated that inflammation plays a key role in developing ERAF. Short term postoperative use of corticosteroids to reduce ERAF post-RFCA has not been vigorously studied. Methods: This was a case-control study of consecutive patients undergoing RFCA for the management of AF at a single-institution. RFCA was performed by a single operator from October 2005 through July 2009. Patients receiving intravenous corticosteroids immediately following the ablation and for 48 hours (6 doses) constituted the treatment group. Controls received no intravenous corticosteroids during their hospitalization. All other management strategies were similar between the 2 groups, including the administration of AADs post- operatively. All patients had continuous electrocardiographic monitoring throughout their hospitalization. Multivariable logistic regression analysis was used to determine the impact of intravenous corticosteroids on ERAF defined as any AF>10 minutes during hospitalization. Results: A total of 68 patients undergoing RFCA for the management of AF were included in this analysis. The overall ERAF rate, irrespective of intravenous corticosteroid use, was 23.5%. The administration of intravenous corticosteroids (n=37; mean±SD dexamethasone mean dose 11.9±4.6 mg/day; range 4-16 mg/day) was associated with an 82% reduction in patients' odds of ERAF (adjusted odds ratio; 0.18, 95% confidence interval [CI] 0.04 to 0.78) compared with those who did not receive corticosteroids (n=31). A dose-response effect was also observed, with a 17% reduction in ERAF odds for each dexamethasone mg-equivalent administered (adjusted odds ratio; 0.83, 95%CI 0.73 to 0.96). Conclusions: The use of intravenous corticosteroids was associated with a dose-dependent reduction in the odds of developing ERAF after RFCA for the management of AF.