Risk of stroke/systemic embolism,major bleeding and associated costs in non-valvular atrial fibrillation patients who initiated apixaban,dabigatran or rivaroxaban compared with warfarin in the United States Medicare population

Objective: To compare the risk and cost of stroke/systemic embolism (SE) and major bleeding between each direct oral anticoagulant (DOAC) and warfarin among non-valvular atrial fibrillation (NVAF) patients.

Methods: Patients (≥65 years) initiating warfarin or DOACs (apixaban, rivaroxaban, and dabigatran) were selected from the Medicare database from 1 January 2013 to 31 December 2014. Patients initiating each DOAC were matched 1:1 to warfarin patients using propensity score matching to balance demographics and clinical characteristics. Cox proportional hazards models were used to estimate the risks of stroke/SE and major bleeding of each DOAC vs. warfarin. Two-part models were used to compare the stroke/SE- and major-bleeding-related medical costs between matched cohorts.

Results: Of the 186,132 eligible patients, 20,803 apixaban–warfarin pairs, 52,476 rivaroxaban–warfarin pairs, and 16,731 dabigatran–warfarin pairs were matched. Apixaban (hazard ratio [HR]?=?0.40; 95% confidence interval [CI] 0.31, 0.53) and rivaroxaban (HR?=?0.72; 95% CI 0.63, 0.83) were significantly associated with lower risk of stroke/SE compared to warfarin. Apixaban (HR?=?0.51; 95% CI 0.44, 0.58) and dabigatran (HR?=?0.79; 95% CI 0.69, 0.91) were significantly associated with lower risk of major bleeding; rivaroxaban (HR?=?1.17; 95% CI 1.10, 1.26) was significantly associated with higher risk of major bleeding compared to warfarin. Compared to warfarin, apixaban ($63 vs. $131) and rivaroxaban ($93 vs. $139) had significantly lower stroke/SE-related medical costs; apixaban ($292 vs. $529) and dabigatran ($369 vs. $450) had significantly lower major bleeding-related medical costs.

Conclusions: Among the DOACs in the study, only apixaban is associated with a significantly lower risk of stroke/SE and major bleeding and lower related medical costs compared to warfarin.     

Impact of renal function on ischemic stroke and major bleeding rates in nonvalvular atrial fibrillation patients treated with warfarin or rivaroxaban: a retrospective cohort study using real-world evidence

Objectives: Renal dysfunction is associated with increased risk of cardiovascular disease and is an independent predictor of stroke and systemic embolism. Nonvalvular atrial fibrillation (NVAF) patients with renal dysfunction may face a particularly high risk of thromboembolism and bleeding. The current retrospective cohort study was designed to assess the impact of renal function on ischemic stroke and major bleeding rates in NVAF patients in the real-world setting (outside a clinical trial).

Methods: Medical claims and Electronic Health Records were retrieved retrospectively from Optum’s Integrated Claims–Clinical de-identified dataset from May 2011 to August 2014. Patients with NVAF treated with warfarin (2468) or rivaroxaban (1290) were selected. Each treatment cohort was stratified by baseline estimated creatinine clearance (eCrCl) levels. Confounding adjustments were made using inverse probability of treatment weights (IPTWs). Incidence rates and hazard ratios of ischemic stroke and major bleeding events were calculated for both cohorts.

Results: Overall, patients treated with rivaroxaban had an ischemic stroke incidence rate of 1.9 per 100 person-years (PY) while patients treated with warfarin had a rate of 4.2 per 100 PY (HR?=?0.41 [0.21–0.80], p?=?.009). Rivaroxaban patients with an eCrCl below 50?mL/min (N?=?229) had an ischemic stroke rate of 0.8 per 100 PY, while the rate for the warfarin cohort (N?=?647) was 6.0 per 100 PY (HR?=?0.09 [0.01–0.72], p?=?.02). For the other renal function levels (i.e. eCrCl 50–80 and ≥80?mL/min) HRs indicated no statistically significant differences in ischemic stroke risks. Bleeding events did not differ significantly between cohorts stratified by renal function.

Conclusions: Ischemic stroke rates were significantly lower in the overall NVAF population for rivaroxaban vs. warfarin users, including patients with eCrCl below 50?mL/min. For all renal function groups, major bleeding risks were not statistically different between treatment groups.     

Continuation with apixaban treatment is associated with lower risk for hospitalization and medical costs among elderly patients

Objective: To compare the risk of hospitalization and costs associated with major bleeding (MB) or stroke/systemic embolism (SE) among elderly patients with nonvalvular atrial fibrillation (NVAF) who initiated apixaban then switched to another oral anticoagulant (OAC) vs. those who continued with apixaban treatment.

Methods: NVAF patients (≥65?years) initiating apixaban were identified from the Humana database (1 January 2013–30 September 2017) and grouped into switcher and continuer cohorts. For switchers, the earliest switch from apixaban to another OAC was defined as the index event/date. A random date during apixaban treatment was selected as the index date for continuers. Patients were followed from index date to health plan disenrollment or 31 December 2017, whichever was earlier. Multivariable regression analyses were used to examine the association of switchers vs. continuers with risk of MB-related or stroke/SE-related hospitalization and healthcare costs during follow-up.

Results: Of 7858 elderly NVAF patients included in the study, 14% (N?=?1110; mean age: 78?years) were switchers; 86% (N?=?6748; mean age: 79?years) were continuers. Apixaban switchers vs. continuers had significantly greater risk of MB-related hospitalization (hazard ratio [HR]: 2.00; 95% CI: 1.52–2.64; p?<?.001) during follow-up; risk of stroke/SE hospitalization did not differ significantly (HR: 1.36, 95% CI: 0.89–2.06, p?=?.154). MB- and stroke/SE-related medical costs were higher for switchers vs. continuers, although total all-cause healthcare costs were similar.

Conclusion: Elderly patients with NVAF in the US who continued with apixaban treatment had a lower risk of MB-related hospitalization and lower MB- and stroke/SE-related medical costs compared to patients who switched to another OAC.     

Cefoperazone-sulbactam and risk of coagulation disorders or bleeding: a retrospective cohort study

ABSTRACT

Objectives: Limited evidence has suggested that cefoperazone-sulbactam causes coagulation disorders and bleeding.

Methods: The authors conducted a retrospective study to compare patients receiving cefoperazone-sulbactam versus those treated with cefoperazone-tazobactam or ceftazidime. Propensity-score matching was used to explore whether treatment with cefoperazone-sulbactam increased the risk of prothrombin time (PT) prolongation, coagulation disorders, and bleeding, or decreased platelets (PLT).

Results: The cohort included 23,242 patients. Among patients receiving cefoperazone-sulbactam, the risk of PT prolongation, coagulation disorders, decreased PLT, and bleeding was 5.3%, 9.2%, 15.7%, and 4.2%, respectively. Propensity-score matching analyses suggested that cefoperazone-sulbactam increased the risk of PT prolongation (aOR 2.26, 95% CI 1.61–3.18), coagulation disorders (aOR 1.81, 95% CI 1.43–2.30), and decreased PLT (aOR 1.46, 95% CI 1.25–1.72), but not increase bleeding (aOR 1.05, 95% CI 0.79–1.40) compared with ceftazidime. Patients receiving cefoperazone-sulbactam had higher risk of PT prolongation (aOR 1.53, 95% CI 1.11–2.10), coagulation disorders (aOR 1.53, 95% CI 1.21–1.95), but not decreased PLT (aOR 0.93, 95% CI 0.81–1.07) or bleeding (aOR 1.11, 95% CI 0.87–1.42), compared with those receiving cefoperazone-tazobactam.

Conclusion: Cefoperazone-sulbactam may be associated with a higher risk of PT prolongation and coagulation disorders compared with cefoperazone-tazobactam and ceftazidime.     

The hidden costs of anticoagulation in hospitalized patients with non-valvular atrial fibrillation

Introduction: Non-valvular atrial fibrillation (NVAF) and ischemic stroke are collectively associated with annual hospital costs of tens of billions of dollars in the USA. Oral anticoagulant (OAC) treatment with warfarin reduces the risk of stroke in patients with NVAF. Unfortunately, because of the complexity of warfarin therapy and potential for adverse events (AEs), many patients who might benefit go untreated or receive suboptimal therapy, increasing their stroke and/or bleeding risk.

Areas covered: This review explores current hospital costs and resource utilization for NVAF patients on warfarin therapy and the potential impact of newer OACs in this area.

Expert opinion: Many ischemic strokes could be prevented through wider use of OACs. Further, admissions due to anticoagulant-associated AEs could be reduced by optimizing OAC therapy. In the hospital, specialized anticoagulation services can decrease costs by improving the effectiveness of warfarin management, empowering patients through education and optimizing care transitions. With fewer interactions and no dose titration or monitoring required, the novel OACs (NOACs) have the potential to further decrease inpatient resource utilization and costs. It is important that, as data become available, inpatient costs are included in cost–benefit comparisons between warfarin and the NOACs.     

New evidences for old concerns with oral anticoagulation in atrial fibrillation: focus on dabigatran

Introduction: Nonvalvular atrial fibrillation (NVAF) is associated with a fivefold excess risk of stroke. Antithrombotic therapy is crucial to reduce the risk of stroke. During past decades, vitamin K antagonists (warfarin or acenocoumarol) have been widely used for this purpose. However, they have several disadvantages that limit their daily use in clinical practice.

Areas covered: In patients with NVAF at risk of stroke, the randomized evaluation of long-term anticoagulation therapy (RE-LY) trial demonstrated that, compared with warfarin, dabigatran 150 mg b.i.d. was associated with lower rates of stroke and systemic embolism but similar rates of major hemorrhage, whereas dabigatran 110 mg b.i.d. exhibited similar rates of stroke and systemic embolism, but lower rates of major hemorrhage. Fortunately, data about dabigatran are not limited to RE-LY trial. In fact, many substudies have been drawn, providing new and important evidences about the benefits of dabigatran.

Expert opinion: The most recent evidences about efficacy and safety of dabigatran in patients with NVAF, focusing on different substudies of RE-LY trial, are reviewed. In summary, dabigatran is beneficial not only in general population with NVAF but also in different subgroups of patients or different clinical settings (i.e., CHADS2 score, INR control, type of AF, elderly, previous transient ischemic attack or stroke, cardioversion and so on).     

Safety,effectiveness, and health care cost comparisons among elderly patients with venous thromboembolism prescribed warfarin or apixaban in the United States Medicare population

Abstract

Objective: To compare safety, effectiveness, and healthcare costs of major bleeding (MB), clinically relevant non-major (CRNM) bleeding, recurrent venous thromboembolism (VTE), and all-cause hospitalization among elderly Medicare VTE patients prescribed warfarin vs apixaban.

Methods: Using 100% Medicare data, elderly patients prescribed apixaban or warfarin within 30 days after a VTE encounter were identified. Patients had continuous health plan enrollment and no parenteral or oral anticoagulant use ≤6 months preceding the VTE encounter. Cohorts were balanced using 1:1 propensity score matching (PSM). Cox proportional hazard models were used to assess the risk of MB, CRNM bleeding, recurrent VTE, and all-cause hospitalization. Generalized linear and two-part models were used to estimate MB-, recurrent VTE-, and all-cause related costs (per patient per month [PPPM]).

Results: In the pre-matched cohort, 25,284 (66.9%) patients were prescribed warfarin and 12,515 (33.1%) apixaban. After 1:1 PSM, 11,363 matched pairs of apixaban-warfarin patients were included for a mean follow-up of 4.0 and 4.4 months, respectively. Matched cohorts had a mean age of 78 years and mean Charlson Comorbidity Index score of 2.9. Warfarin was associated with a higher risk of MB (hazard ratio [HR]?=?1.31; 95% confidence interval [CI]?=?1.10–1.57) and CRNM bleeding (HR?=?1.31; 95% CI?=?1.19–1.43) vs apixaban. The risks of recurrent VTE (HR?=?0.96; 95% CI?=?0.70–1.33) and all-cause hospitalization (HR?=?1.05; 95% CI?=?0.99–1.12) were similar among warfarin and apixaban patients. Warfarin patients had higher MB-related ($147 vs $75; p?=?.003) and all-cause costs PPPM ($3,267 vs $3,033; p?<?.001), but similar recurrent VTE-related medical costs PPPM ($30 vs $36; p?=?.516) vs apixaban patients.

Conclusions: Warfarin was associated with significantly higher risk of MB and CRNM bleeding as well as higher MB-related and all-cause costs vs apixaban patients. Recurrent VTE risk and costs were similar among warfarin and apixaban patients.     

Long-term outcome in patients with non-valvular atrial fibrillation on dabigatran: a prospective cohort study

ABSTRACT

Introduction: Most studies on thromboembolic and bleeding risk in patients with non-valvular atrial fibrillation (NVAF) exposed to non-vitamin K oral anticoagulants stem from interrogation of insurance databases.

Areas covered: We studied 742 consecutive patients with NVAF who started treatment with dabigatran in three hospitals in Italy. Average follow-up was 1.80 years.

Mean age was 76.2 years. CHA₂DS₂VASc score was 0–1 in 37 (5%), 2 in 97 (13%) and ≥ 3 in 604 (82%) patients. NVAF was permanent in 349 (48%). Overall, 76% of patients remained on treatment over the entire follow-up period. Among 180 patients who discontinued permanently, the most frequent reasons were dyspepsia (33.9%), bleeding (17.8%), and renal worsening (12.1%). About 48% and 74% of permanent discontinuations occurred during the first 6 and 12 months of treatment, respectively. Rates of major events (per 100 patient-years) were 0.75 for stroke, 0.31 for myocardial infarction, 1.50 for all-cause death, and 1.80 for major bleedings. The rate of intracranial bleedings was 0.45 and that of major gastrointestinal bleedings was 0.75.

Expert opinion: This prospective cohort study confirms the low incidence of stroke, major bleeding and intracranial bleeding, and a 76% persistence with treatment, in patients with NVAF treated with dabigatran over about 2 years.     

Effectiveness and safety of rivaroxaban in nonvalvular atrial fibrillation: data from a contemporary Spanish registry

Objective: To ascertain the clinical profile, management and rates of thromboembolic and bleeding complications in a contemporary cohort of patients with nonvalvular atrial fibrillation (NVAF) on rivaroxaban treatment, with a particular focus on some subgroups of patients.

Methods: Retrospective study that included all NVAF patients who started treatment with rivaroxaban for the prevention of stroke or systemic embolism between December 2012 and December 2015. Rates of outcomes (stroke, nonfatal myocardial infarction, major bleeding, intracranial bleeding and death) during follow-up were calculated.

Results: A total of 732 patients (mean age 76.4?±?9.2?years; 54.5% women) were included. Comorbidities were common (hypertension 87.5%; diabetes 26.5%; renal insufficiency 24.6%; prior stroke/transient ischemic attack 16.8%). Mean CHA₂DS₂-VASc was 3.9?±?1.5 and HAS-BLED 2.3?±?0.9; 61.9% of patients were rivaroxaban naïve users. After a mean treatment period of 22.7?±?7.4?months, rates of stroke, nonfatal myocardial infarction, major bleeding, intracranial bleeding and death were 1.8, 1.0, 3.2, 0.4 and 5.5 events per 100 patient-years, respectively. Rates of stroke and death were higher in patients >75?years (vs. ≤75?years) and in patients with prior stroke/transient ischemic attack or renal insufficiency. Rates of major bleeding were higher among patients >75?years and in patients with prior stroke/transient ischemic attack.

Conclusions: In this contemporary Spanish cohort of NVAF patients on rivaroxaban, patients had many comorbidities, a high thromboembolic risk and a moderate bleeding risk. Overall, rates of stroke and bleeding complications were low and similar to other previous studies. These data suggest that rivaroxaban is effective and safe in routine practice.     

Non-vitamin-K oral anticoagulants (NOACs) for the prevention of secondary stroke

ABSTRACT

Introduction: In patients with atrial fibrillation (AF), oral anticoagulation with vitamin K antagonists (VKA) (warfarin, phenprocoumon) is effective both for primary and secondary stroke prevention with a 60–70% relative reduction in stroke risk compared with placebo. Mortality is reduced by 26%. VKA have a number of well-documented shortcomings which were overcome by non-vitamin-K oral anticoagulants (NOACs).

Areas covered: Results of randomized trials for four NOACs (apixaban, dabigatran, edoxaban, rivaroxaban) have been published (ARISTOTLE, RE-LY, ENGAGE, ROCKET-AF). In this review, the authors discuss the results in subgroups of patients with prior transient ischemic attacks or ischemic stroke. In aggregate, the NOACs are superior to warfarin for secondary prevention and result in a 50% reduction in intracerebral hemorrhage. Apixaban was superior to aspirin in the AVERROES trial and had a similar rate of major bleeding complications.

Expert opinion: NOACs add to the therapeutic options for secondary stroke prevention in patients with AF and offer advantages over warfarin including a favorable bleeding profile and convenience of use. Aspirin should no longer be used for secondary stroke prevention in patients with AF.     

Non-vitamin K Antagonist Oral Anticoagulants Versus Warfarin in Patients with Atrial Fibrillation and Liver Disease: A Meta-Analysis and Systematic Review

Background

The effect of non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF) and liver disease remains largely unresolved. Therefore, we performed a meta-analysis to compare the efficacy and safety of NOACs with warfarin in this population.

Methods

We systematically searched the Cochrane Library, PubMed, and Embase databases for studies reporting the comparisons of NOACs with warfarin in patients with AF and liver disease. A random-effects model was selected to pool the risk ratios (RRs) and 95% confidence intervals (CIs).

Results

A total of six studies with 41,954 participants were included in this meta-analysis. In AF patients with liver disease, compared with warfarin use, the use of NOACs was associated with reduced risks of all-cause death (RR 0.78, 95% CI 0.66–0.93), major bleeding (RR 0.68, 95% CI 0.53–0.88), and intracranial hemorrhage (RR 0.49, 95% CI 0.41–0.59), but had comparable risks of stroke or system embolism (RR 0.80, 95% CI 0.57–1.12) and gastrointestinal bleeding (RR 0.90, 95% CI 0.61–1.34). In AF patients with cirrhosis, NOACs significantly reduced the risks of major bleeding (RR 0.53, 95% CI 0.37–0.76), gastrointestinal bleeding (RR 0.57, 95% CI 0.38–0.84), and intracranial hemorrhage (RR 0.55, 95% CI 0.31–0.97) compared with warfarin.

Conclusions

Based on current publications, the use of NOACs is at least non-inferior to warfarin in patients with AF and liver disease.

     

Comparison of effectiveness and safety of treatment with apixaban vs. other oral anticoagulants among elderly nonvalvular atrial fibrillation patients

Objective: To compare the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) of elderly (≥65 years of age) nonvalvular atrial fibrillation (NVAF) patients initiating apixaban vs. rivaroxaban, dabigatran, or warfarin.

Methods: NVAF patients with Medicare Advantage coverage in the US initiating oral anticoagulants (OACs, index event) were identified from the Humana database (1 January 2013–30 September 2015) and grouped into cohorts depending on OAC initiated. Propensity score matching (PSM), 1:1, was conducted among patients treated with apixaban vs. each other OAC, separately. Rates of S/SE and MB were evaluated in the follow-up. Cox regressions were used to compare the risk of S/SE and MB between apixaban and each of the other OACs during the follow-up.

Results: The matched pairs of apixaban vs. rivaroxaban (n?=?13,620), apixaban vs. dabigatran (n?=?4654), and apixaban vs. warfarin (n?=?14,214) were well balanced for key patient characteristics. Adjusted risks for S/SE (hazard ratio [HR] vs. rivaroxaban: 0.72, p?=?.003; vs. warfarin: 0.65, p?p?p?p?=?.27) and MB (HR: 0.82, p?=?.23) of NVAF patients treated with apixaban vs. dabigatran trended to be lower, but did not reach statistical significance.

Conclusions: In the real-world setting after controlling for differences in patient characteristics, apixaban is associated with significantly lower risk of S/SE and MB than rivaroxaban and warfarin, and a trend towards better outcomes vs. dabigatran among elderly NVAF patients in the US.     

Safety and efficacy of non-vitamin K oral anticoagulants in non-valvular atrial fibrillation: a Bayesian meta-analysis approach

Introduction: Choosing between different non-vitamin K antagonist oral anticoagulants (NOACs) in non-valvular atrial fibrillation (NVAF) is difficult due to the absence of head to head comparative studies. We performed a Bayesian meta-analysis to explore similarities and differences between different NOACs and to rank treatments overall for safety and efficacy outcomes.

Areas covered: Through a systematic literature search we identified randomized controlled Phase III trials of dabigatran, rivaroxaban, apixaban, and edoxaban versus adjusted-dose warfarin in patients with NVAF.

Expert opinion: Warfarin ranked worst for all-cause mortality and intracranial bleedings and had a nil probability of ranking first for any outcome. The risk of major bleeding versus warfarin was lower with apixaban, dabigatran 110 mg, and both doses of edoxaban. All agents reduced the risk of intracranial bleeding versus warfarin. Edoxaban 30 mg was the best among the treatments being compared for major and gastrointestinal bleeding. Dabigatran 150 mg was the best for stroke and systemic embolism. This study suggests that NOACs are generally preferable to warfarin in patients with NVAF. However, safety and efficacy differences do exist among NOACs, which might drive their use in specific subsets of AF patients, allowing prescribers to tailor treatment to distinct patient profiles.     

Anticoagulation in patients with non-valvular atrial fibrillation: an evaluation of stability and early factors that predict longer-term stability on warfarin in a large UK population

ABSTRACT

Objective: To determine the proportion of patients with non-valvular atrial fibrillation (NVAF) treated with warfarin that achieved a 6‐month period within the target INR range (stability). To then evaluate any associations between stability and outcome and to determine whether stability can be predicted by clinical factors at an early stage in warfarin treatment.

Methods: This study was a record linkage study in 1513 patients with NVAF treated with warfarin for a minimum of 6‐months, carried out in a large UK population. The main outcome measures were stability (defined as six months within the target INR range [2.0–3.0]), thromboembolic and bleeding event rates and mortality. Secondary outcome measures were the predictive value of baseline characteristics and other treatment variables.

Results: Stability was achieved in 52% of the study group. Standardised mean survival was significantly higher in the group who achieved stability (? = 16.91 months, p < 0.001) with a hazard ratio of 4.36 (?p < 0.001). The stable group had a lower rate of both thromboembolic events (0.8% vs. 2.3% per patient year) and bleeds recorded on inpatient diagnoses (0.4% vs. 1.2% per patient year). Failure to achieve stable control was associated with age (Odds Ratio [OR] 1.011 (95% Confidence Interval [CI] 1.001–1.021)) and morbidity at baseline (OR 1.015; 95% CI 1.007–1.022). An increase in mean time between visits (OR 0.939; 95% CI 0.926–0.952) and the percentage time in range (OR 0.889; 95% CI 0.879–0.900) was associated with a decrease in the chance of instability. Greater variability in INR was also associated with a failure to achieve stability (OR 1.518; 95% CI 1.427–1.615). Receiver Operator Characteristic (ROC) analysis using data from the first three months of treatment demonstrated good discrimination of stability using age and morbidity at baseline and percentage time in range and frequency of visits during the first three months of treatment (area under curve [AUC] 0.780; standard error [SE] 0.012; 95% CI 0.757–0.803).

Conclusions: Many patients never achieved a period of 6‐months stability and were at increased risk of thromboembolic events and bleeds. Age, morbidity at baseline and variability of INR control in the first three months could be used to predict instability using warfarin. This study infers that patients should be treated more intensively in the early stages of warfarinisation in order to improve outcome.     

Anticoagulation Therapy for Patients with Non-Valvular Atrial Fibrillation

Background: Anticoagulation in patients with atrial fibrillation (AF) is challenging because stroke-risk reduction must be balanced against increased bleeding risk. Objective: We developed a decision model integrating both stroke and bleeding risk schemes to guide optimal use of anticoagulation in AF, and compared model recommendations with warfarin use in a real-world database. Methods: A Markov model based on demographics, CHADS₂ (Congestive Heart Failure, Hypertension, Age of 75 years and greater, Diabetes Mellitus and History of Stroke) stroke and ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) bleed risk scores, and anticoagulation treatment effects from clinical trials simulated health state transitions for recently diagnosed AF patients. The model recommended the treatment with greater quality-adjusted life expectancy. Model recommendations were contrasted with actual warfarin use recorded in the Thomson Reuters MarketScan database (N=64 946). Results: 74.8% (n = 48 548) of the Marketscan AF cohort had CHADS₂ ≥1, of whom 14.3% had moderate/high (≥4) ATRIA bleeding risk. While the model recommended warfarin for almost all patients with CHADS₂ ≥1 who are at low bleeding risk, it recommended warfarin for fewer patients as bleeding risk increased. Of the 44 611 patients recommended warfarin, 63.4% of patients were considered warfarin exposed (concordant with model recommendation), and of the 20 335 patients recommended aspirin (ace-tylsalicylic acid), 59.7% received warfarin (discordant with model recommendations). Actual warfarin use decreased modestly with higher stroke risk (p< 0.0001) and with higher bleeding risk (p< 0.0001). Conclusion: High discordance between actual warfarin use and model recommendations suggests that anticoagulation decisions are not based on systematic evaluation of stroke and bleeding risks. Model-based clinical decision aids may improve oral anticoagulation decisions by more systematically weighing bleed and stroke risk.     

CMS hospital readmission reduction program and anticoagulants received following a total hip and knee arthroplasty discharge

Objectives: To assess association between 30?day readmission rate and treatment received after total hip and knee arthroplasty (THA/TKA) discharge (rivaroxaban vs. warfarin or non-anticoagulant). To subsequently model impact of increasing rivaroxaban use on the Hospital Readmission Reduction Program (HRRP) penalty, which was imposed on hospitals with excess 30?day readmissions after hospitalizations for selected conditions, including THA/TKA.

Methods: The US Truven Health MarketScan Medicare Supplemental database from 1 July 2010 to 30 April 2015 was used. A retrospective claims analysis was conducted to assess the risk of all-cause 30?day readmission among patients receiving either rivaroxaban or warfarin, or no anticoagulation following THA/TKA discharge. Simulations were performed to estimate the impact of post-discharge treatment on the HRRP penalty.

Results: The risk-adjusted all-cause 30?day readmission rates were 1.21% (95% confidence interval [95% CI]: 0.94%–1.49%), 1.41% (95% CI: 1.19%–1.58%) and 1.95% (95% CI: 1.81%–2.11%) for rivaroxaban, warfarin and non-anticoagulant cohorts, respectively. Using these rates, simulations illustrated that when switching patients from warfarin or non-anticoagulant to rivaroxaban, annual penalty per hospital would be reduced up to 67% or 88%, respectively.

Conclusions: Rivaroxaban treatment post-THA/TKA discharge reduced the risk of 30?day readmission compared to non-anticoagulants. Simulations illustrated that increasing rivaroxaban use could decrease the HRRP penalty.