Payer approval and rejection of oral anticoagulant prescriptions and prescription abandonment patterns among patients with venous thromboembolism.

BACKGROUND: Venous thromboembolism (VTE) is a major public health condition that renders patients at risk of recurrent events, which significantly increases their morbidity, mortality, and health care costs. Apart from warfarin, direct oral anticoagulants, such as apixaban, dabigatran, or rivaroxaban, are approved for VTE treatment. Cardiovascular drugs are largely impacted by formulary restrictions; however, the impact on oral anticoagulants (including warfarin and direct oral anticoagulants) in VTE has not been well studied. OBJECTIVE: To describe the extent of payer-rejected claims for oral anticoagulants for VTE and the factors associated with rejected claims. Prescription abandonment of oral anticoagulants and the time to an eventual fill for oral anticoagulant after rejection or abandonment were also evaluated. METHODS: A retrospective cohort study was conducted among patients with VTE newly prescribed an oral anticoagulant (first claim was the index) between October 2016 and October 2021. Descriptive statistics were used to describe the proportion of patients with paid (ie, filled), rejected, or abandoned index oral anticoagulant prescription and journey to paid prescription among those with initial rejection. Multivariable logistic regression was used to identify factors associated with initial rejection. RESULTS: Among the overall sample (N = 297,312), 74.3% had initial oral anticoagulant prescriptions approved, 9.1% had them rejected, and 16.7% abandoned them. Of the patients with initial rejection, 82.1% eventually filled their oral anticoagulant prescriptions; however, for 14.2% of these patients, the first fill was for an oral anticoagulant other than that initially prescribed. The mean time to a first fill for an oral anticoagulant after an initial rejection was 18.3 days. More than half of the patients with an initial rejected oral anticoagulant claim had at least 1 additional rejection during the follow-up period. Of the patients who abandoned their initial oral anticoagulant prescription, 83.9% filled an oral anticoagulant prescription during follow-up; the mean time to fill for the index oral anticoagulant was 15.6 days. Oral anticoagulant type, Medicare payer coverage, prescribing physician specialty, and VTE diagnosis setting of care were significantly associated with index oral anticoagulant claim rejection (P < 0.05). CONCLUSIONS: Rejection and abandonment may delay access to oral anticoagulant treatment. Factors contributing to these scenarios should be understood and addressed for proper VTE management.

Temporal trends in anticoagulation use and clinical outcomes among medicare beneficiaries with non-valvular atrial fibrillation.

PURPOSE: Oral anticoagulants effectively prevent stroke/systemic embolism among patients with non-valvular atrial fibrillation but remain under-prescribed. This study evaluated temporal trends in oral anticoagulant use, the incidence of stroke/systemic embolism and major bleeding, and economic outcomes among elderly patients with non-valvular atrial fibrillation and CHA2DS2-VASc scores ≥ 2. METHODS: Retrospective analyses were conducted on Medicare claims data from January 1, 2012 through December 31, 2017. Non-valvular atrial fibrillation patients aged ≥ 65 years with CHA2DS2-VASc scores ≥ 2 were stratified by calendar year (2013-2016) of care to create calendar-year cohorts. Patient characteristics were evaluated across all cohorts during the baseline period (12 months before diagnosis). Treatment patterns and clinical and economic outcomes were evaluated during the follow-up period (from diagnosis through 12 months). RESULTS: Baseline patient characteristics remained generally similar between 2013 and 2016. Although lack of oral anticoagulant prescriptions among eligible patients remained relatively high, utilization did increase progressively (53-58%). Among treated patients, there was a progressive decrease in warfarin use (79-52%) and a progressive increase in overall direct oral anticoagulant use (21-48%). There were progressive decreases in the incidence of stroke/systemic embolism 1.9-1.4 events per 100 person years) and major bleeding (4.6-3.3 events per 100 person years) as well as all-cause costs between 2013 and 2016. CONCLUSIONS: The proportions of patients with non-valvular atrial fibrillation who were not prescribed an oral anticoagulant decreased but remained high. We observed an increase in direct oral anticoagulant use that coincided with decreased incidence of clinical outcomes as well as decreasing total healthcare costs.

Oral anticoagulant underutilization among elderly patients with atrial fibrillation: insights from the United States Medicare database.

BACKGROUND: Oral anticoagulants (OACs) mitigate stroke risk in patients with atrial fibrillation (AF). The study aim was to analyze prevalence and predictors of OAC underutilization. METHODS: Newly diagnosed AF patients with a CHA2DS2-VASc score ≥ 2 were identified from the US CMS Database (January 1, 2013-December 31, 2017). Patients were stratified based on having an OAC prescription versus not and the OAC prescription group was stratified by direct OAC (DOACs) versus warfarin. Multivariable logistic regression models were used to examine predictors of OAC underutilization. RESULTS: Among 1,204,507 identified AF patients, 617,611 patients (51.3%) were not prescribed an OAC during follow-up (mean: 2.4 years), and 586,896 patients (48.7%) were prescribed an OAC during this period (DOAC: 388,629 [66.2%]; warfarin: 198,267 [33.8%]). Age ≥ 85 years (odds ratio [OR] 0.55, 95% confidence interval [CI] 0.55-0.56), female sex (OR 0.96, 95% CI 0.95-0.96), Black race (OR 0.78, 95% CI 0.77-0.79) and comorbidities such as gastrointestinal (GI; OR 0.43, 95% CI 0.41-0.44) and intracranial bleeding (OR 0.29, 95% CI 0.28-0.31) were associated with lower utilization of OACs. Furthermore, age ≥ 85 years (OR 0.92, 95% CI 0.91-0.94), Black race (OR 0.78, 95% CI 0.76-0.80), ischemic stroke (OR 0.77, 95% CI 0.75-0.80), GI bleeding (OR 0.73, 95% CI 0.68-0.77), and intracranial bleeding (OR 0.72, 95% CI 0.65-0.80) predicted lower use of DOACs versus warfarin. CONCLUSIONS: Although OAC therapy prescription is the standard of care for stroke prevention in AF patients, its overall utilization is still low among Medicare patients ≥ 65 years old, with specific patient characteristics that predict underutilization.

Effectiveness and Safety of Direct Oral Anticoagulants Among Patients with Non-valvular Atrial Fibrillation and Multimorbidity.

INTRODUCTION: In the USA, there is a steady rise of atrial fibrillation due to the aging population with increased morbidity. This study evaluated the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) among elderly patients with non-valvular atrial fibrillation (NVAF) and multimorbidity prescribed direct oral anticoagulants (DOACs). METHODS: Using the CMS Medicare database, a retrospective observational study of adult patients with NVAF and multimorbidity who initiated apixaban, dabigatran, or rivaroxaban from January 1, 2012 to December 31, 2017 was conducted. High multimorbidity was classified as having ≥ 6 comorbidities. Cox proportional hazard models were used to evaluate the hazard ratios of S/SE and MB among three 1:1 propensity score matched DOAC cohorts. All-cause healthcare costs were estimated using generalized linear models. RESULTS: Overall 36% of the NVAF study population had high multimorbidity, forming three propensity score matched (PSM) cohorts: 12,511 apixaban-dabigatran, 60,287 apixaban-rivaroxaban, and 12,567 dabigatran-rivaroxaban patients. Apixaban was associated with a lower risk of stroke/SE and MB when compared with dabigatran and rivaroxaban. Dabigatran had a lower risk of stroke/SE and a similar risk of MB when compared with rivaroxaban. Compared to rivaroxaban, apixaban patients incurred lower all-cause healthcare costs, and dabigatran patients incurred similar all-cause healthcare costs. Compared to dabigatran, apixaban patients incurred similar all-cause healthcare costs. CONCLUSION: Patients with NVAF and ≥ 6 comorbid conditions had significantly different risks for stroke/SE and MB when comparing DOACs to DOACs, and different healthcare expenses. This study's results may be useful for evaluating the risk-benefit ratio of DOAC use in patients with NVAF and multimorbidity.

Contemporary clinical and economic outcomes among oral anticoagulant treated and untreated elderly patients with atrial fibrillation: Insights from the United States Medicare database.

BACKGROUND: Oral anticoagulants (OACs) mitigate the risk of stroke in atrial fibrillation (AF) patients. OBJECTIVE: Elderly AF patients who were treated with OACs (apixaban, dabigatran, edoxaban, rivaroxaban, or warfarin) were compared against AF patients who were not treated with OACs with respect to their clinical and economic outcomes. METHODS: Newly diagnosed AF patients were identified between January 2013 and December 2017 in the Medicare database. Evidence of an OAC treatment claim on or after the first AF diagnosis was used to classify patients into treatment-defined cohorts, and these cohorts were further stratified based on the initial OAC prescribed. The risks of stroke/systemic embolism (SE), major bleeding (MB), and death were analyzed using inverse probability treatment weighted time-dependent Cox regression models, and costs were compared with marginal structural models. RESULTS: The two treatment groups were composed of 1,421,187 AF patients: OAC treated (N = 583,350, 41.0% [36.4% apixaban, 4.9% dabigatran, 0.1% edoxaban, 26.7% rivaroxaban, and 31.9% warfarin patients]) and untreated (N = 837,837, 59.0%). OAC-treated patients had a lower adjusted risk of stroke/SE compared to untreated patients (hazard ratio [HR]: 0.70; 95% confidence interval [CI]: 0.68-0.72). Additionally patients receiving OACs had a lower adjusted risk of death (HR: 0.56; 95% CI: 0.55-0.56) and a higher risk of MB (HR: 1.57; 95% CI: 1.54-1.59) and this trend was consistent across each OAC sub-group. The OAC-treated cohort had lower adjusted total healthcare costs per patient per month ($4,381 vs $7,172; p < .0001). CONCLUSION: For the OAC-treated cohort in this elderly US population, stroke/SE and all-cause death were lower, while risk of MB was higher. Among OAC treated patients, total healthcare costs were lower than those of the untreated cohort.

Non-persistence to Oral Anticoagulation Treatment in Patients with Non-valvular Atrial Fibrillation in the USA.

BACKGROUND: Studies have shown that patients with non-valvular atrial fibrillation (NVAF) who discontinue oral anticoagulants (OACs) are at higher risk of complications such as stroke. OBJECTIVE: This analysis compared the risk of non-persistence with OACs among patients with NVAF. METHODS: Adult patients with NVAF who initiated apixaban, dabigatran, rivaroxaban, or warfarin were identified using 01JAN2013-30JUN2019 data from Centers for Medicare and Medicaid Services and four US commercial claims databases. Non-persistence was defined as discontinuation (no evidence of index OAC use for ≥ 60 days from the last days' supply) or switch to another OAC. Kaplan-Meier curves were generated to illustrate time to non-persistence along with cumulative incidences of non-persistence. Baseline and time-varying covariates were evaluated, and adjusted Cox proportional hazards models were used to evaluate non-persistence risk. RESULTS: In total, 363,823 patients receiving apixaban, 57,121 receiving dabigatran, 282,831 receiving rivaroxaban, and 317,337 receiving warfarin were included. Of these, 47-72% discontinued/switched OAC therapy within an average 9-month follow-up. Apixaban was associated with a lower risk of non-persistence than were dabigatran (hazard ratio [HR] 0.62; 95% confidence interval [CI] 0.61-0.62), rivaroxaban (HR 0.76; 95% CI 0.75-0.76), and warfarin (HR 0.74; 95% CI 0.74-0.75). Dabigatran was associated with a higher risk of non-persistence than were warfarin (HR 1.21; 95% CI 1.19-1.22) and rivaroxaban (HR 1.23; 95% CI 1.22-1.25), and rivaroxaban was associated with a lower risk of non-persistence than was warfarin (HR 0.98; 95% CI 0.97-0.98). Clinical events (stroke/systemic embolism and major bleeding [MB]) during follow-up were predictors of non-persistence (stroke HR 1.57; 95% CI 1.53-1.61; MB HR 2.96; 95% CI 2.92-3.00). CONCLUSION: In over one million patients with NVAF, our results suggest differences in anticoagulation treatment persistence across OAC agents, even after accounting for clinical events after OAC initiation. It is important for clinicians and patients to take these differences into consideration, especially as non-persistence to OAC therapy is associated with thromboembolic complications.

Effectiveness and Safety of Apixaban Versus Warfarin in Obese Patients with Nonvalvular Atrial Fibrillation Enrolled in Medicare and Veteran Affairs.

Real-world studies have evaluated the use of anticoagulants in obese patients with nonvalvular atrial fibrillation (NVAF), but they have been limited by sample size or the use of diagnosis codes on claims to define obesity. This retrospective study used body weight data of ≥100 kg or a body mass index of ≥30 kg/m2 to identify elderly (aged ≥65 years) NVAF patients with obesity in dually enrolled Veterans Affairs and fee-for-service Medicare patients. It evaluated the risk of stroke/systemic embolism (SE) and major bleeding (MB) in patients that initiated apixaban versus warfarin. Stabilized inverse probability treatment weighting was used to balance the baseline characteristics between patients prescribed apixaban and warfarin in obese patients. Cox models were used to evaluate the relative risk of stroke/SE and MB. Overall, 35.9% (n = 26,522) of the NVAF population were obese, of which 13,604 apixaban and 12,918 warfarin patients were included. After inverse probability treatment weighting, patient characteristics were balanced. The mean age was 75 years, the mean CHA2DS2-VASc score (Congestive Heart Failure, Hypertension, Age ≥75 [Doubled], Diabetes Mellitus, Prior Stroke or Transient Ischemic Attack [Doubled], Vascular Disease, Age 65-74, Female) was 3.8, the mean HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) Score was ∼2.6, and >98% of patients were males. Obese apixaban patients were associated with a similar risk of stroke/SE (hazard ratio: 0.82; 95% confidence interval: 0.66 to 1.03) and a significantly lower risk of MB (hazard ratio: 0.62; 95% confidence interval: 0.54 to 0.70) versus warfarin. No significant interaction was observed between treatment and obesity status (nonobese, obese/nonmorbid, obese/morbid) for stroke/SE (interaction p = 0.602) or MB (interaction p = 0.385). In obese patients with NVAF, apixaban was associated with a similar risk of stroke/SE and a significantly lower risk of MB versus warfarin.

Safety and effectiveness of apixaban compared with warfarin among clinically-relevant subgroups of venous thromboembolism patients in the United States Medicare population.

BACKGROUND: The AMPLIFY trial found significantly lower major bleeding (MB) and similar recurrent venous thromboembolism (VTE) risks associated with apixaban vs warfarin among patients with VTE. OBJECTIVES: To compare MB, clinically-relevant non-major (CRNM) bleeding, and recurrent VTE risks among clinically-relevant subgroups of newly diagnosed elderly patients with VTE prescribed apixaban vs warfarin. METHODS: US Medicare patients prescribed apixaban or warfarin within 30 days post-VTE encounter were identified. Propensity score matching (PSM) was used to control for patient characteristics. Cox models were used to assess MB, CRNM bleeding, and recurrent VTE. Subgroup analyses were conducted for index VTE encounter type, index VTE diagnosis type, index VTE etiology, sex, and frailty. RESULTS: Post-PSM, 11,363 matched pairs of patients prescribed apixaban or warfarin were identified. Apixaban had lower MB (Hazard Ratio [HR]:0.76; 95% CI:0.64-0.91) and similar recurrent VTE risks (HR:1.04; 95% CI:0.75-1.43) vs warfarin. No significant interactions were observed between treatment and index VTE encounter type, index VTE diagnosis type, or sex for risk of MB, CRNM bleeding, or recurrent VTE. Significant interactions: frail patients prescribed apixaban had a 15% lower, while non-frail patients prescribed apixaban had 32% lower CRNM bleeding risk vs those prescribed warfarin. Patients with provoked VTE prescribed apixaban trended toward a higher, while those with unprovoked VTE trended toward a lower risk of recurrent VTE vs patients prescribed warfarin. CONCLUSIONS: Apixaban was associated with significantly lower risks of MB and CRNM bleeding, and similar risk of recurrent VTE as compared with warfarin across the overall population and most subgroups.

Utilization of anticoagulants and predictors of treatment among hospitalized patients with atrial fibrillation in the USA.

OBJECTIVE: To evaluate utilization of anticoagulants (ACs) and the predictors of treatment of patients with a diagnosis of atrial fibrillation (AF) during a hospital stay in the USA. METHODS: Patients (≥18 years of age) who had a primary or secondary discharge diagnosis code of AF during a hospitalization (without a diagnosis of venous thromboembolism) were identified from the Premier Hospital database (1 January 2016-30 September 2017). AC treatments were examined during hospitalizations to assign AF patients into 3 study cohorts: those who received an oral AC (OAC), those who received parenteral AC only, and those who did not receive AC therapy. Multivariable logistic regression analyses were carried out to evaluate potential predictors of receiving parenteral AC only vs. OAC therapy, no AC therapy vs. OAC therapy, as well as the specific OAC drug choices. RESULTS: Of the patients hospitalized with an AF diagnosis (n = 482,729; mean age: 74.7 years; 46.8% female; 82.9% White; 79.4% with Medicare), 42.6% received OAC therapy (most commonly, warfarin or apixaban), 35.3% parenteral AC only, and 22.2% no AC therapy. A key predictor of not receiving OAC therapy was having an AF diagnosis in the second position (applicable to 87.4% of study population). Greater comorbidity level and prior baseline bleeding were strong predictors of receiving parenteral AC only or not receiving any AC therapy vs. receiving OAC therapy. Predictors of receiving warfarin vs. apixaban included higher stroke risk and prior baseline bleeding. LIMITATIONS: OAC utilization may have been underestimated since outpatient OAC utilization was not included in the analysis. CONCLUSIONS: A substantial portion of hospitalized AF patients did not receive any AC therapy, particularly those patients with an AF diagnosis in the second position on hospital records. The predictors of inpatient AC treatment that were identified may be helpful in the clinical decision-making process for patients who are hospitalized with AF.

Clinical characteristics and treatment patterns of patients with venous thromboembolism (VTE) transitioning from hospital to post-discharge settings.

OBJECTIVE: This study examined anticoagulant use during and after a hospital encounter for venous thromboembolism (VTE), a transition of care largely uncharacterized in the literature. METHODS: Adults with a VTE diagnosis code during a hospital encounter (emergency department [ED], observation area [OBS], or inpatient hospital [IP]) from January 2012 to August 2017 were identified in an electronic health records database. The first such hospital encounter was defined as the index VTE encounter. Patients were linked to a claims database and required to be continuously enrolled for six months before the index admission date through six months after the index discharge date. Anticoagulants administered during the index VTE encounter and filled on or within 30 days of discharge were summarized descriptively overall, and by the type of index VTE encounter (IP, No IP) and anticoagulants administered during the index VTE encounter. RESULTS: Among 2,968 eligible patients, mean (SD) age was 64 (16) years, 51% were female, 67% had an IP index VTE encounter, and 77% received anticoagulation therapy during the index VTE encounter. In total, 60% filled a prescription order for anticoagulant within 30 days post-discharge. Of those who received a direct oral anticoagulant (DOAC), warfarin, or parenteral anticoagulant only during the index VTE encounter, 74%, 69%, and 34%, respectively, filled a prescription for the same anticoagulant post-discharge. Patients treated with a DOAC or warfarin during an ED or OBS VTE encounter without a subsequent inpatient hospitalization were more likely to remain on the same anticoagulation therapy post-discharge than those with an inpatient hospitalization (81% vs 69% for DOAC and 75% vs 68% for warfarin). CONCLUSIONS: Many patients treated with anticoagulation therapy during a VTE hospital encounter did not fill a prescription for an anticoagulant within 30 days post-discharge, highlighting an opportunity for improved management of care transitions in this patient population.

A review of global health technology assessments of non-VKA oral anticoagulants in non-valvular atrial fibrillation.

BACKGROUND: This review assessed global health technology assessment (HTA) reports and recommendations of non-vitamin K oral anticoagulants (NOACs) in non-valvular atrial fibrillation (NVAF). METHODS: NHTA agency websites were searched for HTA reports evaluating NOACs versus NOACs or vitamin K antagonists. HTA methods and information on patient involvement/access were collected and empirically analyzed. RESULTS: The review identified 38 unique HTA reports published between 2012 and 2017 in 16 countries including 11 in Europe. NOACs that were cost-effective per local willingness-to-pay (WTP) thresholds were positively recommended for the treatment of NVAF. WTP thresholds ranged from €20,000 to 69,000. Apixaban was recommended in 10/12 (83%) countries, dabigatran in 9/13 (69%) countries, and rivaroxaban in 10/13 (76%) over warfarin. Edoxaban was recommended in 5/7 (71%) countries. Economic evaluations and recommendations comparing NOACs were sparse (two or three countries per NOAC) and generally favored apixaban and edoxaban, followed by dabigatran. Eleven HTA reports from four countries considered the patient voice (Canada [n = 3], Scotland [n = 3], England [n = 4], Brazil [n = 1]); however, only 2/11 (18%) developed recommendations based on this. Among the reports with a positive recommendation, 26/30 (87%) featured a decision that aligned with the approved regulatory label. CONCLUSIONS: Most agencies recommended NOACs over warfarin for patients with NVAF. Few countries made statements recommending one NOAC over another. Given different WTP thresholds, a drug that is cost-effective in one market may not be in another. Therefore, the various NOAC recommendations from HTA agencies cannot be generalized across different countries.

Comparative Clinical and Economic Outcomes Associated with Warfarin Versus Apixaban in the Treatment of Patients with Venous Thromboembolism in a Large U.S. Commercial Claims Database.

BACKGROUND: Venous thromboembolism (VTE), constituting deep vein thrombosis (DVT) and pulmonary embolism (PE), is a common cause of vascular-related morbidity and mortality, resulting in a significant clinical and economic burden in the United States each year. Clinical guidelines recommend that patients with DVT and PE without cancer should be initiated on anticoagulation therapy with a direct oral anticoagulant over a vitamin K antagonist. Yet there is limited real-world evidence comparing the economic burden of warfarin and apixaban in treating VTE patients in a large commercially insured population. OBJECTIVE: To compare safety and effectiveness of warfarin and apixaban and evaluate associated economic burden in treating VTE patients in a large U.S. commercial health care claims database. METHODS: The PharMetrics Plus database was used to identify oral anticoagulant (OAC)-naive patients aged ≥ 18 years who initiated apixaban or warfarin within 30 days of a qualifying VTE encounter and had continuous health plan enrollment with medical and pharmacy benefits for 6 months before treatment initiation. Apixaban initiators and warfarin initiators were matched using the propensity score matching (PSM) technique. Cox proportional hazard models were used to assess and compare the risk of major bleeding (MB), clinically relevant nonmajor (CRNM) bleeding, and recurrent VTE. Generalized linear models were used to assess and compare the all-cause health care costs. A 2-part model with bootstrapping was used to evaluate MB- and recurrent VTE-related medical costs. RESULTS: Among 25,193 prematched patients, 13,421 (53.3%) were prescribed warfarin and 11,772 (46.7%) were prescribed apixaban. After 1:1 PSM, 8,858 matched warfarin-apixaban pairs were selected with a mean follow-up of 109 days and 103 days, respectively. Warfarin was associated with a significantly higher risk of MB (HR = 1.52, 95% CI = 1.14-2.04), CRNM bleeding (HR = 1.27, 95% CI = 1017.15-1.40), and recurrent VTE (HR = 1.50, 95% CI = 1.24-1.82) compared with apixaban. Warfarin patients had significantly higher all-cause medical costs per patient per month (PPPM; $2,333 vs. $1,992; P = 0.001), MB-related costs PPPM ($112 vs. $65; P = 0.020), and recurrent VTE-related costs PPPM ($287 vs. $206; P = 0.014) compared with apixaban patients. Warfarin patients had similar all-cause total health care costs PPPM ($2,630 vs. $2,420; P = 0.051) compared with apixaban patients. CONCLUSIONS: Warfarin use was associated with a higher risk of MB, CRNM bleeding, and recurrent VTE compared with apixaban. Warfarin use was also associated with higher all-cause medical costs, MB-related medical costs, and recurrent VTE-related costs PPPM compared with apixaban. DISCLOSURES: This study was funded by Bristol Myers Squibb and Pfizer, which were also involved in the study design, as well as writing and revising of the manuscript. Guo, Rajpura, Okano, and Rosenblatt are employees of Bristol Myers Squibb. Hlavacek, Mardekian, and Russ are employees of Pfizer. Keshishian, Sah, Delinger, and Mu are employees of SIMR, LLC, which received funding from the study sponsors to conduct this study.

Comparison of inpatient admission rates of patients treated with apixaban vs. warfarin for venous thromboembolism in the emergency department.

Objectives: This study evaluated inpatient admission status, hospitalization length of stay (LOS), hospital costs, and readmissions of patients who were diagnosed with venous thromboembolism (VTE) and treated with apixaban or warfarin in the emergency department (ED).Methods: Patients (≥18 years) with an ED visit with a primary discharge diagnosis code of VTE were identified from the Premier Hospital database (8/1/2014-5/31/2018). Patients who received apixaban or warfarin during the ED visit were selected and grouped into two treatment cohorts. Outcomes of ED disposition (discharged or admitted to the inpatient setting), hospital LOS, hospital cost of index event, and rate of 1-month readmissions were compared for the study cohorts.Results: Of the overall study population, 30.5% (n = 12,174; mean age: 59.7 years) received apixaban and 69.5% (n = 27,767; mean age: 59.3 years) received warfarin for VTE in the ED. After adjusting for patient and hospital characteristics, the regression analysis showed that apixaban was associated with a significantly lower likelihood of admission to the inpatient setting vs. warfarin (Odds Ratio [OR]: 0.12, 95% Confidence Interval [CI]: 0.12 to 0.13; p < 0.001). Correspondingly, mean index hospital LOS was 1.42 days shorter (95% CI: -1.47 to -1.36; p < 0.001) and mean index event hospital cost per patient was significantly lower by $4,276 ($3,732 [95% CI: $3,565 to $3,907] vs. $8,008 [95% CI: $7,676 to $8,355]; p < 0.001). Also, the likelihood of all-cause 1-month readmission was significantly lower for patients treated with apixaban vs. warfarin (OR: 0.85, 95% CI: 0.79 to 0.92; p < 0.001).Conclusions: In the real-world setting, VTE patients with an ED visit who were treated with apixaban vs. warfarin had a lower likelihood of being admitted to the inpatient setting, which was reflected in shorter average LOS and lower average index event cost. Additionally, the risk of 1-month readmission was also lower for patients treated with apixaban vs. warfarin.

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

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.

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.

Comparative clinical outcomes between direct oral anticoagulants and warfarin among elderly patients with non-valvular atrial fibrillation in the CMS medicare population.

Atrial fibrillation (AF) prevalence increases with age; > 80% of US adults with AF are aged ≥ 65 years. Compare the risk of stroke/systemic embolism (SE), major bleeding (MB), net clinical outcome (NCO), and major adverse cardiac events (MACE) among elderly non-valvular AF (NVAF) Medicare patients prescribed direct oral anticoagulants (DOACs) VS warfarin. NVAF patients aged ≥ 65 years who initiated DOACs (apixaban, dabigatran, and rivaroxaban) or warfarin were selected from 01JAN2013-31DEC2015 in CMS Medicare data. Propensity score matching was used to balance DOAC and warfarin cohorts. Cox proportional hazards models estimated the risk of stroke/SE, MB, NCO, and MACE. 37,525 apixaban-warfarin, 18,131 dabigatran-warfarin, and 55,359 rivaroxaban-warfarin pairs were included. Compared to warfarin, apixaban (HR: 0.69; 95% CI 0.59-0.81) and rivaroxaban (HR: 0.82; 95% CI 0.73-0.91) had lower risk of stroke/SE, and dabigatran (HR: 0.88; 95% CI 0.72-1.07) had similar risk of stroke/SE. Apixaban (MB: HR: 0.61; 95% CI 0.57-0.67; NCO: HR: 0.64; 95% CI 0.60-0.69) and dabigatran (MB: HR: 0.79; 95% CI 0.71-0.89; NCO: HR: 0.84; 95% CI 0.76-0.93) had lower risk of MB and NCO, and rivaroxaban had higher risk of MB (HR: 1.08; 95% CI 1.02-1.14) and similar risk of NCO (HR: 1.04; 95% CI 0.99-1.09). Compared to warfarin, apixaban had a lower risk for stroke/SE, MB, and NCO; dabigatran had a lower risk of MB and NCO; and rivaroxaban had a lower risk of stroke/SE but higher risk of MB. All DOACs had lower risk of MACE compared to warfarin.