Medical costs in the US of clinical events associated with oral anticoagulant (OAC) use compared to warfarin among non-valvular atrial fibrillation patients ≥75 and <75 years of age, based on the ARISTOTLE, RE-LY, and ROCKET-AF trials

Comparison of all-cause costs and healthcare resource use among patients with newly-diagnosed non-valvular atrial fibrillation newly treated with oral anticoagulants

OBJECTIVES

Compare costs and healthcare resource utilization (HCRU) among newly-diagnosed non-valvular atrial fibrillation (NVAF) patients newly treated with dabigatran vs apixaban, rivaroxaban, or warfarin.

METHODS

Newly-diagnosed adult NVAF patients initiating dabigatran, apixaban, rivaroxaban, or warfarin (index event) between October 1, 2010-December 31, 2014 were identified using MarketScan claims data, and followed until medication discontinuation, switch, inpatient death, enrollment end, or study end (December 31, 2015). Dabigatran patients were propensity-score matched 1:1 separately with apixaban, rivaroxaban, and warfarin patients. Per-patient-per-month (PPPM) all-cause cost, HCRU, and 30-day re-admissions were reported. Costs were analyzed using generalized linear models.

RESULTS

Final cohorts, each matched with dabigatran patients, included 8,857 apixaban patients, 26,592 rivaroxaban patients, and 33,046 warfarin patients. Dabigatran patients had lower adjusted PPPM total healthcare, inpatient, and outpatient costs compared to rivaroxaban ($4,093 vs $4,636, $1,476 vs $1,862, and $2,016 vs $2,121, respectively, all p ≤ .001) and warfarin ($4,199 vs $4,872, $1,505 vs $1,851, and $2,049 vs $2,514, respectively, all p < .001). Adjusted costs were similar for dabigatran and apixaban. Dabigatran patients had significantly fewer hospitalizations, outpatient visits, and pharmacy claims than rivaroxaban patients (0.06 vs 0.07, 4.84 vs 4.96 and 4.80 vs 4.93, respectively, all p < .020) and warfarin patients (0.06 vs 0.07, 4.77 vs 6.88, and 4.76 vs 5.89, respectively, all p < .001). Dabigatran patients had similar hospitalizations to apixaban, but higher outpatient visits (4.70 vs 4.31) and pharmacy claims (4.86 vs 4.61), both p < .001.

CONCLUSIONS

This real-world study found adjusted all-cause costs were lower for dabigatran compared to rivaroxaban and warfarin patients and similar to apixaban patients.

All-Cause, Stroke/Systemic Embolism-, and Major Bleeding-Related Health-Care Costs Among Elderly Patients With Nonvalvular Atrial Fibrillation Treated With Oral Anticoagulants

In this study, all-cause, stroke/systemic embolism (SE)-related, and major bleeding (MB)-related health-care costs among elderly patients with nonvalvular atrial fibrillation (NVAF) initiating treatment with different oral anticoagulants (OACs) were compared. Patients ≥65 years of age initiating OACs, including apixaban, rivaroxaban, dabigatran, and warfarin, were identified from the Humana Research Database between January 1, 2013, and September 30, 2015. Propensity score matching was used to separately match the different OAC cohorts with the apixaban cohort. All-cause health-care costs and stroke/SE-related and MB-related medical costs per patient per month (PPPM) were compared using generalized linear or 2-part regression models. Compared to apixaban, rivaroxaban was associated with significantly higher all-cause health-care costs (US$2234 vs US$1846 PPPM, P < .001) and MB-related medical costs (US$106 vs US$47 PPPM, P < .001), dabigatran was associated with significantly higher all-cause health-care costs (US$1980 vs US$1801 PPPM, P = .007), and warfarin was associated with significantly higher all-cause health-care costs (US$2386 vs US$1929 PPPM, P < .001), stroke/SE-related medical costs (US$42 vs US$18 PPPM, P < .001), and MB-related medical costs (US$132 vs US$51 PPPM, P < .001). Among elderly patients with NVAF, other OACs were associated with higher all-cause health-care costs than apixaban.

Sex-Specific Comparative Effectiveness of Oral Anticoagulants in Elderly Patients With Newly Diagnosed Atrial Fibrillation

BACKGROUND

Sex-specific comparative effectiveness of direct oral anticoagulants among patients with nonvalvular atrial fibrillation is not known. Via this retrospective cohort study, we assessed the sex-specific, comparative effectiveness of direct oral anticoagulants (rivaroxaban and dabigatran), compared to each other and to warfarin among patients with atrial fibrillation.

METHODS AND RESULTS

Elderly (aged ≥66 years) Medicare beneficiaries enrolled in Medicare Part D benefit plan from November 2011 to October 2013 with newly diagnosed atrial fibrillation formed the study cohort (65 734 [44.8%] men and 81 137 [55.2%] women). Primary outcomes of inpatient admissions for ischemic strokes and major bleeding were compared across the 3 drugs (rivaroxaban: 20 mg QD, dabigatran: 150 mg BID, or warfarin) using 3-way propensity-matched samples. In men, rivaroxaban use decreased stroke risk when compared with warfarin use (hazard ratio, 0.69; 95% confidence interval, 0.48-0.99; P=0.048) and dabigatran use (hazard ratio, 0.66; 95% confidence interval, 0.45-0.96; P=0.029) and was associated with a similar risk of any major bleeding when compared with warfarin and dabigatran. In women, although ischemic stroke risk was similar in the 3 anticoagulant groups, rivaroxaban use significantly increased the risk for any major bleeding when compared with warfarin (hazard ratio, 1.20; 95% confidence interval, 1.03-1.42; P=0.021) and dabigatran (hazard ratio, 1.27; 95% confidence interval, 1.09-1.48; P=0.011).

CONCLUSIONS

The reduced risk of ischemic stroke in patients taking rivaroxaban, compared with dabigatran and warfarin, seems to be limited to men, whereas the higher risk of bleeding seems to be limited to women.

Setting priorities in the health care sector - the case of oral anticoagulants in nonvalvular atrial fibrillation in Denmark

Aim

Resources devoted to health care are limited, therefore setting priorities is required. It differs between countries whether decision-making concerning health care technologies focus on broad economic perspectives or whether focus is narrow on single budgets (“silo mentality”). The cost perspective as one part of the full health economic analysis is important for decision-making. With the case of oral anticoagulants in patients with nonvalvular atrial fibrillation (NVAF), the aim is to discuss the implication of the use of different cost perspectives for decision-making and priority setting.

Methods

In a cost analysis, the annual average total costs of five oral anticoagulants (warfarin and non-vitamin K oral anticoagulants [NOACs; dabigatran, rivaroxaban, apixaban, and edoxaban]) used in daily clinical practice in Denmark for the prevention of stroke in NVAF patients are analyzed. This is done in pairwise comparisons between warfarin and each NOAC based on five potential cost perspectives, from a “drug cost only” perspective up to a “societal” perspective.

Results

All comparisons of warfarin and NOACs show that the cost perspective based on all relevant costs, ie, total costs perspective, is essential for the choice of therapy. Focusing on the reimbursement costs of the drugs only, warfarin is the least costly option. However, with the aim of therapy to prevent strokes and limit bleedings, including the economic impact of this, all NOACs, except rivaroxaban, result in slightly lower health care costs compared with warfarin. The same picture was found applying the societal perspective.

Conclusion

Many broad cost-effectiveness analyses of NOACs exist. However, in countries with budget focus in decision-making this information does not apply. The present study’s case of oral anticoagulants has shown that decision-making should be based on health care or societal cost perspectives for optimal use of limited resources. Otherwise, the risk is that suboptimal decisions will be likely.

Treatment with direct oral anticoagulants in patients with upper extremity deep vein thrombosis

Background

Upper extremity deep vein thrombosis (UEDVT) constitutes around 10% of all DVT, and can cause both pulmonary embolism (PE) and postthrombotic syndrome (PTS) in the arm. The incidence of secondary UEDVT is increasing due to widespread use of central venous catheters in patients with cancer and other chronic diseases. The safety and efficacy of using new direct acting oral anti coagulants (DOAC) in the treatment of UEDVT has not been systematically evaluated. Our aims were to evaulate efficacy, safety, and risk of recurrence of venous thromboembolism (VTE) during DOAC treatment in UEDVT patients.

Methods

Data from the Swedish national anticoagulation registry (AuriculA) was retrospectively evaluated for all 55 patients (27 men aged 23–86 years, and 28 women aged 18–75 years) treated with DOAC because of UEDVT between 2012 and 2015 in the southernmost hospital region of Sweden with 1.3 million inhabitants in 2016. Patients were followed for 6 months.

Results

During 6 months after institution of DOAC treatment there was one recurrence (2%) of DVT during treatment and two (4%) recurrences after cessation of treatment. No patient died, whereas one (2%) suffered a clinically relevant nonmajor bleeding.

Conclusion

DOAC can be used in the treatment of UEDVT patients with acceptable efficacy and safety.

Effect of Apixaban Versus Warfarin Use on Health Care Resource Utilization and Costs Among Elderly Patients with Nonvalvular Atrial Fibrillation

BACKGROUND

The clinical trial ARISTOTLE showed that apixaban was superior to warfarin in reducing the risks of stroke and bleeding among patients with nonvalvular atrial fibrillation (NVAF). Further study of the effect of apixaban versus warfarin use on health care resource utilization (HCRU) and associated costs in the real-world setting is warranted, especially among elderly patients who are at higher risk of stroke and bleeding.

OBJECTIVE

To compare HCRU and costs among elderly NVAF patients treated with apixaban versus warfarin in the United States.

METHODS

Elderly patients (aged ≥ 65 years) with Medicare coverage who initiated apixaban or warfarin were identified from the Humana research database during January 1, 2013-September 30, 2015. Patients were required to have 12 months of continuous insurance coverage before drug initiation (baseline period) and an atrial fibrillation diagnosis during the baseline period or on the date of drug initiation. NVAF patients were grouped into cohorts depending on the drug initiated. Propensity score matching (PSM) was conducted to control for differences in demographics and clinical characteristics of study cohorts. Patients were followed after the index date for a variable length of follow-up. All-cause and disease-specific HCRU and costs during the follow-up were evaluated before and after PSM and reported as per patient per year.

RESULTS

Of the overall (unmatched) population, 8,250 patients (mean age: 78.0 years) initiated apixaban and 14,051 patients (mean age: 78.2 years) initiated warfarin. Among NVAF patients who initiated apixaban versus those who initiated warfarin, mean Charlson Comorbidity Index (CCI) scores (3.0 vs. 3.4, P < 0.001); stroke risk scores, including CHADS₂ (2.7 vs. 2.9, P < 0.001) and CHA₂DS₂-VASc (4.6 vs. 4.7, P < 0.001); and bleeding risk scores, including HAS-BLED (3.1 vs. 3.2, P < 0.001), were lower. Additionally, total annual all-cause health care costs were lower during the baseline period for patients treated with apixaban versus warfarin ($17,077 vs. $20,236, P < 0.001). After PSM, 14,214 patients were matched, with 7,107 in each cohort. Mean age, CCI score, and stroke and bleeding risks were similar between matched cohorts, as were total all-cause health care costs during the baseline period. During the follow-up among matched cohorts, apixaban versus warfarin treatment was associated with higher annual pharmacy costs ($5,159 vs. $2,867, P < 0.001) but lower annual inpatient ($8,327 vs. $14,296, P < 0.001), outpatient ($9,655 vs. $11,469, P < 0.001), and total all-cause health care costs ($23,141 vs. $28,633, P < 0.001), which were reflective of lower inpatient, outpatient, and all-cause HCRU among apixaban-treated patients. Furthermore, bleeding-related ($2,101 vs. $3,963, P < 0.001) and stroke-related ($652 vs. $1,178, P = 0.001) annual medical costs were lower for patients treated with apixaban versus warfarin.

CONCLUSIONS

After controlling for differences in patient characteristics, in the real-world setting apixaban versus warfarin use was associated with less HCRU and lower total all-cause health care costs and costs for bleeding- and stroke-related medical services, but greater pharmacy costs, among elderly NVAF patients.

DISCLOSURES

This study was sponsored by Pfizer and Bristol-Myers Squibb. Deitelzweig is a consultant for Pfizer and Bristol-Myers Squibb and has served on their advisory boards and received speaker fees. Deitelzweig also serves as consultant and advisory board member to Portola and Janssen. Luo, Trocio, and Mardekian are employees of Pfizer and own stock in the company. Gupta and Curtice are employees of Bristol-Myers Squibb and own stock in the company. Lingohr-Smith, Menges, and Lin are employees of Novosys Health, which received research funds from Pfizer and Bristol-Myers Squibb to conduct this study and develop the manuscript. Study concept and design were primarily contributed by Deitelzweig, Luo, and Gupta, along with Trocio, Mardekian, Curtice, and Lin. Lin, Menges, and Lingohr-Smith took the lead in data collection, with assistance from the other authors. Data interpretation was performed by Deitelzweig, Menges, and Lin, with assistance from the other authors. The manuscript was written by Lingohr-Smith and Menges, along with the other authors, and revised by all the authors. Some aspects of this study were presented at the American Heart Association Scientific Sessions in New Orleans, Louisiana, November 12-16, 2016.

Individualized approaches to thromboprophylaxis in atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia worldwide. The prevalence of AF in persons older than 55 years is at least 33.5 million globally and is predicted to more than double in the next half-century. Anticoagulation, heart rate control, and heart rhythm control comprise the 3 main treatment strategies in AF. Anticoagulation is aimed at preventing debilitating stroke, systemic embolism, and associated mortality. Historically, anticoagulation in AF was achieved with a vitamin K antagonist such as warfarin, which is supported by evidence demonstrating reduced incident stroke and all-cause mortality. However, warfarin has unpredictable pharmacokinetics with many drug-drug interactions that require regular monitoring to ensure patients remain in the therapeutic anticoagulant range. Non-vitamin K antagonist oral anticoagulants including dabigatran, rivaroxaban, apixaban, and edoxaban provide a possible solution to these issues with their more predictable pharmacokinetics, rapid onset of action, and greater specificity. Results from large randomized, controlled trials indicate that these agents are at least noninferior to warfarin in prevention of stroke. These trials also demonstrate a consistently lower incidence of intracranial hemorrhage, almost always all life-threatening bleeds, and many forms of major bleeds with the possible exception of gastrointestinal and some other forms of mucosal bleeding, compared with warfarin. Patients with AF are a heterogeneous population with diverse risk of stroke and bleeding, and different subgroups respond differently to anticoagulation. Important clinical questions have arisen regarding optimal anticoagulation drug selection in distinct populations such as those with renal impairment, older age, coronary artery disease, and heart failure as well as those at particularly high risk for bleeding or thromboembolism. In this review, treatment strategies in AF management are discussed in the context of different individual subgroups of patients.

[New oral anticoagulants for prophylaxis of stroke. Results of an expert conference on practical use in geriatric patients]

Geriatric patients with non-valvular atrial fibrillation (AF) are increasingly being treated with novel oral anticoagulants (NOAC) to prevent ischemic stroke. This article highlights the outcome of an expert meeting on the practical use of NOAC in elderly patients. An interdisciplinary group of experts discussed the current situation of stroke prevention in geriatric patients and its practical management in daily clinical practice. The topic was examined through focused impulse presentations and critical analyses as the basis for the expert consensus. The key issues are summarized in this paper. The European Society of Cardiology (ESC) guidelines from 2012 for the management of patients with non-valvular AF recommend NOAC as the preferred treatment and vitamin K antagonists (VKA) only as an alternative option. Currently, the NOAC factor Xa inhibitors apixaban and rivaroxaban and the thrombin inhibitor dabigatran are more commonly used in clinical practice for patients with AF. Although these drugs have many similarities and are often grouped together it is important to recognize that the pharmacology and dose regimes differ between compounds. Especially n elderly patients NOAC drugs have some advantages compared to VKA, e.g. less drug-drug interactions with concomitant medication and a more favorable risk-benefit ratio mostly driven by the reduction of bleeding. Treatment of anticoagulation in geriatric patients requires weighing the serious risk of stroke against an equally high risk of major bleeding and pharmacoeconomic considerations. Geriatric patients in particular have the greatest benefit from NOAC, which can also be administered in cases of reduced renal function. Regular control of the indications is indispensable, as also for all other medications of the patient. The use of NOAC should certainly not be withheld from geriatric patients who have a clear need for oral anticoagulation.

Relationship of hospital-associated bleeding with length of stay and total hospitalization costs in patients hospitalized for atrial fibrillation

BACKGROUND

While literature has focused on the impact of bleeding beginning outside the hospital setting among patients with atrial fibrillation (AF), there is little information regarding bleeding that first occurs within a hospital setting. This study was performed to determine the association between hospital-associated bleeding in patients admitted for AF on outcomes of length of stay (LOS) and total hospitalization cost.

METHODS AND RESULTS

The Premier research database was queried to identify adult inpatients discharged between 2008-2011 having a primary diagnosis code for AF where a bleeding diagnosis code was not present on admission. Regression was used to adjust for baseline differences in patients to estimate outcomes comparing patients with and without a hospital-associated bleed. There were 143,287 patients that met the study criteria. There were 2991 (2.1%) patients identified with a hospital associated bleed. After adjustment for covariates, the mean estimated LOS was significantly greater in the bleed group, at 6.0 days (95% CI = 5.8-6.1) vs the no bleed group at 3.3 days (95% CI = 3.3-3.3) (p < 0.0001). Similarly, the adjusted mean estimated total hospitalization cost was also significantly greater in the bleed group, $12,069 (95% CI = $11,779-$12,366) vs $6561 (95% CI = $6538-$6583) in the no bleed group (p < 0.0001).

CONCLUSIONS

After adjustments for baseline differences the data show that the 2.1% (n = 2991) of patients with hospital associated bleeding accounted for an estimated additional 8106 hospitalization days and $16.4 million dollars in cost over the study period compared to non-bleeders.

Nurses' self-reported time estimation of anticoagulation therapy: a survey of warfarin management in long-term care

BACKGROUND

A nursing shortage in the United States has resulted in increased workloads, potentially affecting the quality of care. This situation is particularly concerning in long-term care (LTC) facilities, where residents are older, frailer, and may be receiving multiple medications for comorbidities, thus requiring a greater commitment of nurse time. We conducted a survey of LTC nurses to determine how much of their time each week is spent managing newly started and stable warfarin-treated residents.

METHODS

Forty LTC nurses validated the questionnaire to determine what protocols/procedures are involved in warfarin management. Twenty LTC nurses completed the survey, quantifying the time they spend on procedures related to warfarin management, and how often they performed each procedure for each resident each week.

RESULTS

The nurses reported that 26% of their residents were receiving warfarin; the majority (approximately 75%) of these residents began warfarin after admission to the facility. On average, the nurses spent 4.6 hours per week for treatment procedures and monitoring patients initiating warfarin therapy and 2.35 hours per week for each resident who was stable on warfarin therapy on admission. Overall, to care for an average number of newly initiated and stable warfarin patients in a medium-size LTC facility, staff nurses are estimated to spend 68 hours per week. Study limitations include the potential for bias because of the small sample size, representativeness of the sample, and the possibility of inaccuracies in respondents' self-reported time estimation of warfarin-related procedures.

CONCLUSIONS

In the context of a well-documented and expanding nursing shortage in the United States, the substantial use of time and resources necessary to initiate, monitor, and manage warfarin treatment in elderly LTC patients is of concern. Until the problem of understaffing is resolved, implementation of therapies that are simpler and require less nursing time-e.g. the use of new oral anticoagulants in the place of warfarin-may be a way to free up nursing time for other essential care tasks.

Selection of Warfarin or One of the New Oral Antithrombotic Agents for Long-Term Prevention of Stroke among Persons with Atrial Fibrillation

OPINION STATEMENT

Atrial fibrillation (AF) is the most common sustained cardiac rhythm disorder, which can potentially increases the risk of stroke by five-fold, thus, resulting in high public healthcare burden. Stroke prevention is vital in the management of AF patients. Vitamin K antagonists (VKA, eg, warfarin) have been the mainstay treatment to prevent ischemic stroke and systemic thromboembolism in AF patients for several decades. Despite the efficacy of warfarin, its limitations have recently driven the advent of some new antithrombotic agents, the non-VKA oral anticoagulant (NOACs, including dabigatran, rivaroxaban, apixaban, and edoxaban). The NOACs have changed the landscape for thromboembolic prophylaxis among patients with nonvalvular AF. Although three NOACs thus far (dabigatran, rivaroxaban, and apixaban) have been approved in Europe and the United States, for stroke prevention in patients with nonvalvular AF on the basis of several Phase III clinical trials, warfarin still remain important in preventing stroke for patients. This is especially true for those with optimal control of international normalized ratio with high (>70 %) time in therapeutic range, valvular AF or associated prosthetic valve. These NOACs are attractive alternatives for stroke prevention in patients with nonvalvular AF who are unable or unwilling to receive warfarin. However, several issues should be taken into consideration on safe and effective use of these NOACs in day-to-day clinical practice, for example, pharmacological properties, drug interactions, monitoring and compliance, and treatment of frail elderly patients or patients with renal impairment, etc. The decision about whether to initiate oral anticoagulation either with warfarin or NOACs should be patient-centered and after consideration of both stroke and bleeding risks. It is important for clinical practitioner to offer patients with AF an individualized decision about drug choice, making decision after adequate patient education plus discussion about the risks and benefits of these agents, thus fitting the drug to the patient profile.