Cost-Effectiveness of Oral Anticoagulants for Ischemic Stroke Prophylaxis Among Nonvalvular Atrial Fibrillation Patients

Predictors of adherence to direct oral anticoagulants after cardiovascular or bleeding events in Medicare Advantage Plan enrollees with atrial fibrillation

BACKGROUND

Direct oral anticoagulants (DOACs) are recommended for patients with atrial fibrillation (AF) given their improved safety profile. Suboptimal adherence to DOACs remains a significant concern among individuals with AF. However, the extent of adherence to DOACs following a cardiovascular or bleeding event has not been fully evaluated.

OBJECTIVE

To evaluate the pattern of adherence trajectories of DOACs after a cardiovascular or bleeding event and to investigate the sociodemographic and clinical predictors associated with each adherence trajectory by using claims-based data.

METHODS

This retrospective study was conducted among patients with AF prescribed with DOACs (dabigatran/apixaban/rivaroxaban) between July 2016 and December 2017 and who were continuously enrolled in the Texas-based Medicare Advantage Plan. Patients who experienced a cardiovascular or bleeding event while using the DOACs were further included in the analysis. The sample was limited to patients who experienced a clinical event such as a cardiovascular or bleeding event while using the DOACs. The clinical events considered in this study were cardiovascular (stroke, congestive heart failure, myocardial infarction, systemic embolism) and bleeding events. To assess adherence patterns, each patient with a DOAC prescription was followed up for a year after experiencing a clinical event. The monthly adherence to DOACs after these events was evaluated using the proportion of days covered (PDC). A group-based trajectory model incorporated the monthly PDC to classify groups of patients based on their distinct patterns of adherence. Predictors associated with each trajectory were assessed using a multinomial logistic regression model, with the adherent trajectory serving as the reference group in the outcome variable.

RESULTS

Among the 694 patients with AF who experienced clinical events after the initiation of DOACs, 3 distinct adherence trajectories were identified: intermediate nonadherent (30.50%), adherent (37.7%), and low adherent (31.8%); the mean PDC was 0.47 for the intermediate nonadherent trajectory, 0.93 for the adherent trajectory, and 0.01 for low adherent trajectory. The low-income subsidy was significantly associated with lower adherence trajectories (odds ratio [OR] = 4.81; 95% CI = 3.07-7.51) and with intermediate nonadherent trajectories (OR = 1.57; 95% CI = 1.06-2.34). Also, nonsteroidal anti-inflammatory drug use was significantly associated with lower adherence trajectories (OR = 5.10; 95% CI = 1.95-13.36) and intermediate nonadherent trajectories (OR = 3.17; 95% CI = 1.26-7.93). Other predictors significantly associated with both nonadherent trajectories are type of DOACs (OR = 0.53; 95% CI = 0.35-0.79), presence of coronary artery disease (OR = 1.89; 95% CI = 1.01-3.55), and having 2 or more clinical events (OR = 1.65; 95% CI = 1.09-2.50).

CONCLUSIONS

Predictors identified provide valuable insights into the suboptimal adherence of DOACs among Medicare Advantage Plan enrollees with AF, which can guide the development of targeted interventions to enhance adherence in this high-risk patient population.

Methods for Economic Evaluations of Novel Oral Anticoagulants in Patients with Atrial Fibrillation: A Systematic Review

BACKGROUND

Atrial fibrillation (AF) is a severe epidemiological and public health concern among the elderly population worldwide, with substantial economic and social burdens. Economic evaluations can play an essential role in optimizing the utilization of scarce resources. In recent years, the number of economic evaluation studies related to AF has increased due to the rising number of AF patients, the continuous updating of clinical data, and the emergence of real-world evidence. However, there are still deficiencies in model settings and parameter sources in relevant studies.

OBJECTIVE

This study aims to review the existing economic evaluations of novel oral anticoagulants (NOACs) in patients with AF and summarize the evidence and methods applied.

METHODS

A comprehensive and systematic search was conducted on electronic databases, including PubMed, Embase, Web of Science (WOS), and The Cochrane Library, from the date of database creation to November 2022. The reporting quality of included literature was assessed using the Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022) statement.

RESULTS

A total of 102 studies were included in the review, with 200 comparisons between NOACs and vitamin K antagonists (VKAs), as well as 58 comparisons between different NOACs. The healthcare sector and payer perspectives were the most common, and accordingly, the majority of the evaluations considered only direct medical costs. Most studies used Markov cohort models with the number of health states ranging from 4 to 29. Of included studies, 80 (78%) considered event recurrence and complications, and 78 (76%) considered discontinuation and second-line therapy. All of the studies applied uncertainty analysis to explore the robustness of the results. Of all 200 NOACs-VKAs comparisons, 149 (75%) showed that NOACs were more cost-effective; this proportion was 84% (139 out of 165) in high-income countries but decreased to 29% (10 out of 35) in middle- and low-income countries. Most (82%) of the 28 items in the CHEERS 2022 checklist were elucidated in the majority of included studies. A minority (only 39%) of included studies demonstrated high reporting quality.

CONCLUSION

NOACs may be more cost-effective than VKAs in patients with AF, but this conclusion applies to high-income countries, whereas VKAs may be more cost-effective in middle- and low-income countries. The reporting quality of included studies was variable, and certain methodological issues were presented. This study highlights the economic evaluation methodology of NOACs in patients with AF and provides recommendations for modeling methods and future studies.

Cost Effectiveness of Strategies to Manage Atrial Fibrillation in Middle- and High-Income Countries: A Systematic Review

BACKGROUND

Atrial fibrillation (AF) remains the most common form of cardiac arrhythmia. Management of AF aims to reduce the risk of stroke, heart failure and premature mortality via rate or rhythm control. This study aimed to review the literature on the cost effectiveness of treatment strategies to manage AF among adults living in low-, middle- and high-income countries.

METHODS

We searched MEDLINE (OvidSp), Embase, Web of Science, Cochrane Library, EconLit and Google Scholar for relevant studies between September 2022 and November 2022. The search strategy involved medical subject headings or related text words. Data management and selection was performed using EndNote library. The titles and abstracts were screened followed by eligibility assessment of full texts. Selection, assessment of the risk of bias within the studies, and data extraction were conducted by two independent reviewers. The cost-effectiveness results were synthesised narratively. The analysis was performed using Microsoft Excel 365. The incremental cost effectiveness ratio for each study was adjusted to 2021 USD values.

RESULTS

Fifty studies were included in the analysis after selection and risk of bias assessment. In high-income countries, apixaban was predominantly cost effective for stroke prevention in patients at low and moderate risk of stroke, while left atrial appendage closure (LAAC) was cost effective in patients at high risk of stroke. Propranolol was the cost-effective choice for rate control, while catheter ablation and the convergent procedure were cost-effective strategies in patients with paroxysmal and persistent AF, respectively. Among the anti-arrhythmic drugs, sotalol was the cost-effective strategy for rhythm control. In middle-income countries, apixaban was the cost-effective choice for stroke prevention in patients at low and moderate risk of stroke while high-dose edoxaban was cost effective in patients at high risk of stroke. Radiofrequency catheter ablation was the cost-effective option in rhythm control. No data were available for low-income countries.

CONCLUSION

This systematic review has shown that there are several cost-effective strategies to manage AF in different resource settings. However, the decision to use any strategy should be guided by objective clinical and economic evidence supported by sound clinical judgement.

REGISTRATION

CRD42022360590.

Cost-Effectiveness of Direct Oral Anticoagulants in Patients With Nonvalvular Atrial Fibrillation in Hong Kong

OBJECTIVES

The emergence of direct oral anticoagulants (DOACs) has revolutionized the prevention of stroke related to nonvalvular atrial fibrillation (NVAF). Several DOACs are available on the market, while the cost-effectiveness comparison among DOACs and vitamin K antagonist (warfarin) in NVAF management in Hong Kong market remains scarce. The objective of this study was to assess the cost-effectiveness of DOACs and warfarin from a Hong Kong public institutional perspective to inform formulary listing decisions.

METHODS

A previously developed Markov model was adapted to simulate the lifetime disease progression of a hypothetical cohort of 1000 patients. Net monetary costs, quality-adjusted life-year (QALY), and incremental cost-effectiveness ratio were computed for the following competing alternatives: warfarin, apixaban (5 mg twice daily), dabigatran (110 mg or 150 mg twice daily), and rivaroxaban (20 mg once daily). Probabilistic sensitivity analyses were conducted to address study uncertainties.

RESULTS

In base-case results, all DOACs were associated with greater QALYs improvements and lower costs than warfarin. Rivaroxaban, apixaban, dabigatran 150 mg, dabigatran 110 mg, and warfarin resulted in net costs US dollar (USD) 8088, USD 8240, USD 8566, USD 8653, and USD 16 363 and net QALY 5.87, 6.017, 6.022, 5.98, and 5.829, respectively. In probabilistic sensitivity analysis, the probabilities of warfarin, rivaroxaban 20 mg, dabigatran 110 mg, dabigatran 150 mg, and apixaban 5 mg being cost-effective of 2000 iterations were 0%, 0%, 29.4%, 33.2%, and 37.4%, respectively.

CONCLUSION

Apixaban was the most cost-effective option compared with other DOACs and warfarin in the management of NVAF; this conclusion is consistent under all the tested uncertainty scenarios.

Economic evaluation in cardiac electrophysiology: Determining the value of emerging technologies

Cardiac electrophysiology is a constantly evolving speciality that has benefited from technological innovation and refinements over the past several decades. Despite the potential of these technologies to reshape patient care, their upfront costs pose a challenge to health policymakers who are responsible for the assessment of the novel technology in the context of increasingly limited resources. In this context, it is critical for new therapies or technologies to demonstrate that the measured improvement in patients' outcomes for the cost of achieving that improvement is within conventional benchmarks for acceptable health care value. The field of Health Economics, specifically economic evaluation methods, facilitates this assessment of value in health care. In this review, we provide an overview of the basic principles of economic evaluation and provide historical applications within the field of cardiac electrophysiology. Specifically, the cost-effectiveness of catheter ablation for both atrial fibrillation (AF) and ventricular tachycardia, novel oral anticoagulants for stroke prevention in AF, left atrial appendage occlusion devices, implantable cardioverter defibrillators, and cardiac resynchronization therapy will be reviewed.

Time trends in atrial fibrillation-related stroke during 2001–2020 in Sweden: a nationwide, observational study

Background

Great efforts have been made to improve stroke prevention in atrial fibrillation (AF) patients. Meanwhile, incidence of AF is increasing, which may affect the share of AF-related stroke on all strokes. We aimed to examine the temporal trends in the incidence of AF-related ischemic stroke between 2001 and 2020, if it varied by use of novel oral anticoagulant drugs (NOAC), and if the relative risk of ischemic stroke associated with AF changed over time.

Methods

Data from the total Swedish population aged ≥70 years during the period 2001-2020 were used. Annual incidence rate (IR) was calculated for overall and AF-related ischemic stroke which was defined as first-ever ischemic stroke with AF diagnosed up to 5 years before, on the same day, or within 2 months after the stroke event. Cox regression models were performed to examine if the hazard ratio (HR) between AF and stroke changed over time.

Findings

While IR of ischemic strokes declined during 2001-2020, IR of AF-related ischemic stroke remained stable between 2001 and 2010 but showed a consistent decline between 2010 and 2020. The HR of ischemic stroke within 3 years from an AF diagnosis came down from 2.39 (95% confidence interval: 2.31-2.48) to 1.54 (1.48-1.61) over the study period, which was largely explained by a substantial increase in the use of NOAC among AF patients after 2012. Yet, by the end of 2020, 24% of all ischemic strokes had a preceding or concurrent AF diagnosis, which is slightly higher than in 2001.

Interpretation

Even though both the absolute and relative risk of AF-related ischemic stroke declined over the past 20 years, every fourth ischemic stroke in 2020 still had a preceding or concurrent AF diagnosis. This represents a great potential for future gains in stroke prevention among AF patients.

Funding

Swedish Research Council and Loo and Hans Osterman Foundation for Medical Research.

Oral Anticoagulants for Stroke Prevention in Atrial Fibrillation: A Systematic Review of Economic Evaluations

OBJECTIVES

Several studies have evaluated the economic evaluation of a group of medications known as novel oral anticoagulant drugs (NOACs) in recent years. The aim of this study is to review and systematically analyze the cost-utility studies results of warfarin compared with other NOAC drugs in atrial fibrillation patients.

METHODS

A systematic review was performed to identify all studies evaluating the NOAC medications in comparison with warfarin. For this purpose, PubMed, Cochrane Library, ISI Web of Science, and Scopus were searched from 2013 to 2022. Articles were independently screened with inclusion criteria, and full texts were reviewed. First, the Consolidated Health Economic Evaluation Reporting Standards checklist was used to evaluate the quality of the articles. Then, the costs and outcomes of the studies were analyzed, and findings were appraised critically.

RESULTS

A total of 84 costs-per-quality-adjusted life-year (QALY) cases were extracted from the studies in which the share of rivaroxaban, edoxaban, apixaban, and dabigatran were 31%, 13%, 29%, and 27%, respectively. The median cost per QALY of rivaroxaban, edoxaban, apixaban, and dabigatran was 21 910$/QALY, 22 096$/QALY, 17 765$/QALY, and 24 161$/QALY, respectively. Subgroup analysis based on perspective showed that dabigatran had the highest incremental cost-effectiveness ratio (ICER) and edoxaban had the lowest ICER value. Edoxaban and apixaban had the highest and the lowest cost per QALY from an insurance perspective, respectively.

CONCLUSION

Despite the differences and variations in the economic evaluation studies of NOAC drugs, these drugs have shown acceptable cost-effectiveness in developed and developing countries. Among NOAC drugs, apixaban has the lowest ICER and the highest cost-effectiveness.

Economic evaluation of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs) for stroke prevention in patients with atrial fibrillation: a systematic review and meta-analysis

OBJECTIVES

To assess cost-effectiveness of direct oral anticoagulants (DOACs) compared with vitamin K antagonists (VKAs) for stroke prevention in atrial fibrillation (AF) by pooling incremental net benefits (INBs).

DESIGN

Systematic review and meta-analysis.

SETTING

We searched PubMed, Scopus and Centre for Evaluation of Value and Risks in Health Registry from inception to December 2019.

PARTICIPANTS

Patients with AF.

MAIN OUTCOME MEASURES

The INB was defined as a difference of incremental effectiveness multiplied by willing to pay threshold minus the incremental cost; a positive INB indicated favour treatment. These INBs were pooled (stratified by level of country income, perspective, time-horizon, model types) with a random-effects model if heterogeneity existed, otherwise a fixed effects model was applied. Heterogeneity was assessed using Q test and I² statistic. Risk of bias was assessed using the economic evaluations bias (ECOBIAS) checklist.

RESULTS

A total of 100 eligible economic evaluation studies (224 comparisons) were included. For high-income countries (HICs) from a third-party payer (TPP) perspective, the pooled INBs for DOAC versus VKA pairs were significantly cost-effective with INBs (95% CI) of $6632 ($2961.67 to $10 303.72; I²=59.9%), $6353.24 ($4076.03 to $8630.45; I²=0%), $7664.58 ($2979.79 to $12 349.37; I²=0%) and $8573.07 ($1877.05 to $15 269.09; I²=0%) for dabigatran, apixaban, rivaroxaban and edoxaban relative to VKA, respectively but only dabigatran was significantly cost-effective from societal perspective (SP) with an INB of $11 746.96 ($2429.34 to $21 064.59; I²=52.4%). The pooled INBs of all comparisons for upper-middle income countries (UMICs) were not significantly cost-effective. The ECOBIAS checklist indicated that risk of bias was mostly low for most items with the exception of five items which should be less influenced on pooling INBs.

CONCLUSIONS

Our meta-analysis provides comprehensive economic evidence that allows policy makers to generalise cost-effectiveness data to their local context. All DOACs may be cost-effective compared with VKA in HICs with TPP perspective. The pooling results produced moderate to high heterogeneity particularly in UMICs. Further studies are required to inform UMICs with SP.

PROSPERO REGISTERATION NUMBER

CRD 42019146610.

Cost-Effectiveness of Mobile Health-Based Integrated Care for Atrial Fibrillation: Model Development and Data Analysis

BACKGROUND

Mobile health (mHealth) technology is increasingly used in disease management. Using mHealth tools to integrate and streamline care has improved clinical outcomes of patients with atrial fibrillation (AF).

OBJECTIVE

The aim of this study was to investigate the potential clinical and health economic outcomes of mHealth-based integrated care for AF from the perspective of a public health care provider in China.

METHODS

A Markov model was designed to compare outcomes of mHealth-based care and usual care in a hypothetical cohort of patients with AF in China. The time horizon was 30 years with monthly cycles. Model outcomes measured were direct medical cost, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER). Sensitivity analyses were performed to examine the robustness of the base-case results.

RESULTS

In the base-case analysis, mHealth-based care gained higher QALYs of 0.0730 with an incurred cost of US $1090. Using US $33,438 per QALY (three times the gross domestic product) as the willingness-to-pay threshold, mHealth-based care was cost-effective, with an ICER of US $14,936 per QALY. In one-way sensitivity analysis, no influential factor with a threshold value was identified. In probabilistic sensitivity analysis, mHealth-based care was accepted as cost-effective in 92.33% of 10,000 iterations.

CONCLUSIONS

This study assessed the expected cost-effectiveness of applying mHealth-based integrated care for AF according to a model-based health economic evaluation. The exploration suggested the potential cost-effective use of mHealth apps in streamlining and integrating care via the Atrial fibrillation Better Care (ABC) pathway for AF in China. Future economic evaluation alongside randomized clinical trials is highly warranted to verify the suggestion and investigate affecting factors such as geographical variations in patient characteristics, identification of subgroups, and constraints on local implementation.

Direct Medical Cost of Stroke and the Cost-Effectiveness of Direct Oral Anticoagulants in Atrial Fibrillation-Related Stroke: A Cross-Sectional Study

BACKGROUND

Stroke has significant direct medical costs, and direct oral anticoagulants (DOACs) are better alternatives to warfarin for stroke prevention in atrial fibrillation (AF). This study aimed to determine the direct medical costs of stroke, with emphasis on AF stroke and the cost-effectiveness of DOACs among stroke patients in a tertiary hospital in Malaysia.

METHODS

This study utilised in-patient data from the case mix unit of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) between 2011 and 2018. Direct medical costs of stroke were determined using a top-down costing approach and factors associated with costs were identified. Incremental cost effectiveness ratio (ICER) was calculated to compare the cost-effectiveness between DOACs and warfarin.

RESULTS

The direct medical cost of stroke was MYR 11,669,414.83 (n = 3689). AF-related stroke cases had higher median cost of MYR 2839.73 (IQR 2269.79-3101.52). Regression analysis showed that stroke type (AF versus non-AF stroke) (p = 0.013), stroke severity (p = 0.010) and discharge status (p < 0.001) significantly influenced stroke costs. DOACs were cost-effective compared to warfarin with an ICER of MYR 19.25.

CONCLUSIONS

The direct medical cost of stroke is substantial, with AF-stroke having a higher median cost per stroke care. DOACs were cost effective in the treatment of AF-related stroke in UKMMC.

National Trends in Use of and Spending on Oral Anticoagulants Among US Medicare Beneficiaries From 2011 to 2019

This cross-sectional study examines patterns of use of direct oral anticoagulants and their association with Medicare spending.

The association between increasing oral anticoagulant prescribing and atrial fibrillation related stroke in Ireland

AIMS

Recent increases in the number of patients with atrial fibrillation (AF) prescribed oral anticoagulants (OAC) are evident in Ireland and internationally, largely due to the availability of direct oral anticoagulants (DOACs). This study aimed to determine the rate of stroke in the context of increasing anticoagulation utilisation, with a focus on AF-related ischaemic stroke (IS).

METHODS

Dispensing data for OACs were identified for the period 2010-2018 as well as hospital discharges for IS (2005-2018). Irish National Stroke Register data were used to elucidate the characteristics of patients with acute ischaemic stroke.

RESULTS

The number of patients prescribed OACs increased by 94% from 2010-2018 with a significant change from 2013 (β = 2.57, P = .038), associated with a large increase in the number of patients on DOACs. There was 3.3-fold increase in expenditure on OACs nationally from 2013 to 2018, of which 94% was DOAC related. Using the 2013 timepoint, ischaemic stroke rates until 2018 did not show a significant deviation from the previous trend (β = 0.00, P = .898). The percentage of AF-related ischaemic stroke was stable from 2013 to 2017 with a 4.5% decrease in 2018. The percentage of ischaemic stroke patients with previously diagnosed AF decreased from 2013 to 2018; however, there was an increase in the percentage of ischaemic strokes while on OAC in this cohort.

CONCLUSION

Large increases in OAC utilisation have not resulted in changes in ischaemic stroke rates at a national level. The percentage of ischaemic strokes with a previous diagnosis of AF has decreased indicating a possible benefit from greater OAC utilisation. However, the percentage presenting with an ischaemic stroke while on OAC treatment is increasing. The increase in patients presenting with stroke while treated with OAC may largely reflect the national increase in patients prescribed DOACs but the findings raise concerns about treatment failures. The real-world effectiveness of DOACs requires further examination.

Updating the Cost Effectiveness of Oral Anticoagulants for Patients with Atrial Fibrillation Based on Varying Stroke and Bleed Risk Profiles

BACKGROUND

Previous investigations into the cost effectiveness of direct oral anticoagulants only considered individual stroke risk but not bleed risk even though bleeding is an important and potentially fatal side effect for anticoagulated patients.

OBJECTIVE

This study aimed to evaluate the cost effectiveness of dabigatran, rivaroxaban, apixaban, and edoxaban vs warfarin in patients with atrial fibrillation with varying stroke/bleed risk profiles over a lifetime horizon.

METHODS

A Markov micro-simulation was adapted to examine the lifetime costs and quality-adjusted survival of five anticoagulants from a US private payer's perspective. The study hypothetical cohort consisted of 10,000 patients with atrial fibrillation with age, CHA₂DS₂-VASc, and HAS-BLED scores similar to a commercially insured patient with atrial fibrillation cohort. Model input parameters including the efficacy and safety of each strategy, utilities, and cost were estimated from public sources, published literature, and analysis conducted in the IBM MarketScan database. Lifetime cost, quality-adjusted life-years, and incremental cost-effectiveness ratios were assessed for each treatment strategy. Subgroup analyses stratified by age, stroke risk score alone, bleed risk score alone and both were performed. Uncertainty was assessed by a deterministic sensitivity analysis and a probabilistic sensitivity analysis.

RESULTS

The base-case analysis suggested dabigatran was the optimal treatment with an incremental cost-effectiveness ratio of $35,055 per quality-adjusted life-year relative to warfarin. Subgroup analyses stratified by age, stroke risk score, and bleed risk score alone were largely consistent with the base-case analysis. Subgroup analyses stratified by both stroke and bleed risk score showed edoxaban was the preferred treatment in patients with a low stroke and a low or medium bleed risk, and patients with a high stroke and low bleed risk. Apixaban was the preferred treatment in patients with a medium stroke and high bleed risk. Results of the deterministic sensitivity analysis indicate the model results were most sensitive to the drug cost and hazard ratio for stroke and bleeding event. Results of the probability sensitivity analysis showed dabigatran is cost effective vs. other treatments in 32.8% and 42.4% of iterations at a willingness to pay of $50,000/quality-adjusted life-year and a willingness to pay of $100,000/quality-adjusted life year, respectively.

CONCLUSIONS

From a US private payer's perspective, dabigatran appears cost effective compared with other anticoagulants. This study indicated risk stratification especially considering both stroke and bleed risk simultaneously is important not only in clinical practice but also in health technology assessment exercises among patients with atrial fibrillation.

Cost-Effectiveness of Extended and One-Time Screening Versus No Screening for Non-Valvular Atrial Fibrillation in the USA

BACKGROUND

There is limited evidence on the clinical and cost benefits of screening for atrial fibrillation (AF) with electrocardiogram (ECG) in asymptomatic adults.

METHODS

We adapted a previously published Markov model to evaluate the clinical and economic impact of one-time screening for non-valvular AF (NVAF) with a single 12-lead ECG and a 14-day extended screening with a hand-held ECG device (Zenicor single-lead ECG, Z14) compared with no screening. Clinical events considered included ischemic stroke, systemic embolism, major bleeds, myocardial infarction, and death. Epidemiology and effectiveness data for extended screening were from the STROKESTOP study. Risks of clinical events in NVAF patients were derived from ARISTOTLE. Analyses were conducted from the perspective of a third-party payer, considering a population with undiagnosed NVAF, aged 75 years in the USA. Costs and utilities were discounted at a 3% annual rate. Parameter uncertainty was formally considered via deterministic and probabilistic sensitivity analyses (DSA and PSA). Structural uncertainty was assessed via scenario analyses.

RESULTS

In a hypothetical cohort of 10,000 patients followed over their lifetimes, the number of additional AF diagnoses was 54 with 12-lead ECG and 255 with Z14 compared with no screening. Both screening strategies led to better health outcomes (ischemic strokes avoided: ECG 12-lead, 9.8 and Z14, 42.2; quality-adjusted life-years gained: ECG 12-lead, 31 and Z14, 131). Extended screening and one-time screening were cost effective compared with no screening at a willingness-to-pay (WTP) threshold of $100,000 per QALY gained ($58,728/QALY with ECG 12-lead and $47,949/QALY with Z14 in 2016 US dollars). ICERs remained below $100,000 per QALY in all DSA, most PSA runs, and in all scenario analyses except for a scenario assuming low anticoagulation persistence.

CONCLUSIONS

Our analysis suggests that, screening the general population at age 75 years for NVAF is cost effective at a WTP threshold of $100,000. Both extended screening and one-time screening for NVAF are expected to provide health benefits at an acceptable cost.

The Movember Prostate Cancer Landscape Analysis: an assessment of unmet research needs

Prostate cancer is a heterogeneous cancer with widely varying levels of morbidity and mortality. Approaches to prostate cancer screening, diagnosis, surveillance, treatment and management differ around the world. To identify the highest priority research needs across the prostate cancer biomedical research domain, Movember conducted a landscape analysis with the aim of maximizing the effect of future research investment through global collaborative efforts and partnerships. A global Landscape Analysis Committee (LAC) was established to act as an independent group of experts across urology, medical oncology, radiation oncology, radiology, pathology, translational research, health economics and patient advocacy. Men with prostate cancer and thought leaders from a variety of disciplines provided a range of key insights through a range of interviews. Insights were prioritized against predetermined criteria to understand the areas of greatest unmet need. From these efforts, 17 research needs in prostate cancer were agreed on and prioritized, and 3 received the maximum prioritization score by the LAC: first, to establish more sensitive and specific tests to improve disease screening and diagnosis; second, to develop indicators to better stratify low-risk prostate cancer for determining which men should go on active surveillance; and third, to integrate companion diagnostics into randomized clinical trials to enable prediction of treatment response. On the basis of the findings from the landscape analysis, Movember will now have an increased focus on addressing the specific research needs that have been identified, with particular investment in research efforts that reduce disease progression and lead to improved therapies for advanced prostate cancer.

The Movember global Landscape Analysis Committee (LAC) was established to act as an independent group of experts across urology, medical oncology, radiation oncology, radiology, pathology, translational research, health economics and patient advocacy to identify the highest priority research needs across the prostate cancer biomedical research domain. Findings from the landscape analysis illustrate the research priorities in prostate cancer and will enable Movember to focus on specific needs, with particular investment in research to reduce disease progression and improve therapies for advanced prostate cancer.

Warden B. Direct Oral Anticoagulant Use: A Practical Guide to Common Clinical Challenges

Direct oral anticoagulants ( DOAC s) have quickly become attractive alternatives to the long‐standing standard of care in anticoagulation, vitamin K antagonist. DOAC s are indicated for prevention and treatment of several cardiovascular conditions. Since the first approval in 2010, DOAC s have emerged as leading therapeutic alternatives that provide both clinicians and patients with more effective, safe, and convenient treatment options in thromboembolic settings. With the expanding role of DOAC s, clinicians are faced with increasingly complex decisions relating to appropriate agent, duration of treatment, and use in special populations. This review will provide an overview of DOAC s and act as a practical reference for clinicians to optimize DOAC use among common challenging scenarios. Topics addressed include (1) appropriate indications; (2) use in patients with specific comorbidities; (3) monitoring parameters; (4) transitioning between anticoagulant regimens; (5) major drug interactions; and (6) cost considerations.

Warden B. Direct Oral Anticoagulant Use: A Practical Guide to Common Clinical Challenges

Direct oral anticoagulants (DOACs) have quickly become attractive alternatives to the long-standing standard of care in anticoagulation, vitamin K antagonist. DOACs are indicated for prevention and treatment of several cardiovascular conditions. Since the first approval in 2010, DOACs have emerged as leading therapeutic alternatives that provide both clinicians and patients with more effective, safe, and convenient treatment options in thromboembolic settings. With the expanding role of DOACs, clinicians are faced with increasingly complex decisions relating to appropriate agent, duration of treatment, and use in special populations. This review will provide an overview of DOACs and act as a practical reference for clinicians to optimize DOAC use among common challenging scenarios. Topics addressed include (1) appropriate indications; (2) use in patients with specific comorbidities; (3) monitoring parameters; (4) transitioning between anticoagulant regimens; (5) major drug interactions; and (6) cost considerations.

Novel Oral Anticoagulants Compared to Warfarin for Postoperative Atrial Fibrillation After Isolated Coronary Artery Bypass Grafting

BACKGROUND

Postoperative atrial fibrillation (POAF) is common after cardiac surgery and contributes to short- and long-term morbidity, particularly thromboembolism. Anticoagulation for sustained or recurrent POAF is suggested to reduce thromboembolism. Novel oral anticoagulants may present a safe alternative to warfarin with further benefits including shorter hospital length of stay and better patient convenience.

METHODS

A retrospective analysis was performed on all isolated cases of coronary artery surgery (CABG) at our institution between January 2015 and December 2018, totalling 960 patients. Rates of POAF were examined with particular focus on preoperative factors, postoperative outcomes, and anticoagulation practices.

RESULTS

The incidence of POAF was 31.8% (305 patients) and was higher in older patients (67.6±9.4 yrs vs 63.0±10.7 yrs, p<0.001), those with a history of cerebrovascular disease (14.6% vs 8.7%, p=0.02), those with higher CHADS-VASc scores (2.5±1.3 vs 2.8±1.3, p<0.001) those who had a postoperative return to theatre (2.6% vs 0.8%, p=0.002), and those with new renal failure (4.9% vs 1.8%, p=0.02). Off-pump surgery was associated with lower incidence of POAF (29.8% vs 37.1%, p=0.03). Patients who developed POAF had significantly longer admissions than those without (12.6±10.6 days vs 9.3±16.3 days, p<0.001). In total, 106 patients (11.0%) went home anticoagulated; 77 (72.6%) on warfarin and 29 (27.4% on a NOAC). Readmission for bleeding was higher in patients on anticoagulation (1.0% vs 0.0%, p=0.02), but did not drive readmission for pericardial effusion (0.3% vs 0.6%, p=0.55). No bleeding complications occurred in patients who were discharged on a NOAC. Overall mortality at median of 2 years was 1.8% (17 patients) and no mortality occurred in any patient discharged on anticoagulation.

CONCLUSION

Postoperative atrial fibrillation is a common adverse event and is linked to higher preoperative and postoperative morbidity. Anticoagulation may be safely started in these patients and use of novel anticoagulation does not appear to increase postoperative complications, although overall numbers are low.

The Genetics of Warfarin Dose-Response Variability in Africans: An Expert Perspective on Past, Present, and Future

Coumarins such as warfarin are prescribed for prevention and treatment of thromboembolic disorders. Warfarin remains the most widely prescribed and an anticoagulant of choice in Africa. Warfarin use is, however, limited by interindividual variability in pharmacokinetics and a narrow therapeutic index. The difference in patients' pharmacodynamic responses to warfarin has been attributed to genetic variation in warfarin metabolism and molecular targets (e.g., CYP2C9 and VKORC1) and host-environment interactions. This expert review offers a synthesis of human genetics studies in Africans with respect to pharmacogenetics-informed warfarin dosing. We identify areas that need future research attention or could benefit from harnessing existing pharmacogenetics knowledge toward rational and optimal therapeutics with warfarin in African patients. A literature search was conducted until January 2019. A total of 343 articles were retrieved from nine African countries: Botswana, Ethiopia, Egypt, Ghana, Kenya, South Africa, Sudan, Tanzania, and Mozambique. We found 19 studies on genetics of warfarin treatment specifically among Africans. Genes examined included CYP2C9, VKORC1, CYP4F2, APOE, CALU, GGCX, and EPHX1. CYP2C9*2 and *3 alleles were highly frequent among Egyptians, while rare in other African populations. CYP2C9*5, *8, *9, and *11, and VKORC1 Asp36Tyr genetic variants explained warfarin variability in Africans better, compared to CYP2C9*2 and *3. In Africa, there is limited pharmacogenetics data on warfarin. Therefore, future research and funding commitments should be prioritized to ensure safe and effective use of warfarin in Africa. Lessons learned in Africa from the science of pharmacogenetics would inform rational therapeutics in hematology, cardiology, and surgical specialties worldwide.

Real-World Adherence and Persistence to Direct Oral Anticoagulants in Patients With Atrial Fibrillation: A Systematic Review and Meta-Analysis

BACKGROUND

Stroke reduction with direct oral anticoagulants (DOACs) in atrial fibrillation (AF) is dependent on adherence and persistence in the real-world setting. Individual study estimates of DOAC adherence/persistence rates have been discordant. Our aims were to characterize real-world observational evidence for DOAC adherence/persistence and evaluate associated clinical outcomes in patients with AF.

METHODS AND RESULTS

PubMed, EMBASE, and CINAHL were searched from inception to June 2018. Observational studies that reported real-world DOAC adherence/persistence in patients with AF were included. Study quality was assessed using the Newcastle-Ottawa Scale. Meta-analyses for pooled estimates were performed using DerSimonian and Laird random-effects models. Outcomes included DOAC mean proportion of days covered or medication possession ratio, proportion of good adherence (proportion of days covered/medication possession ratio ≥80%), persistence, DOAC versus vitamin K antagonists persistence, and clinical outcomes associated with nonadherence/nonpersistence. Forty-eight observational studies with 594 784 unique patients with AF (59% male; mean age 71 years) were included. The overall pooled mean proportion of days covered/medication possession ratio was 77% (95% CI, 75%-80%), proportion of patients with good adherence was 66% (95% CI, 63%-70%), and proportion persistent was 69% (95% CI, 65%-72%). The pooled proportion of patients with good adherence was 71% (95% CI, 64%-78%) for apixaban, 60% (95% CI, 52%-68%) for dabigatran, and 70% (95% CI, 64%-75%) for rivaroxaban. Similar patterns were found for pooled persistence by agent. The pooled persistence was higher with DOACs than vitamin K antagonists (odds ratio, 1.44 [95% CI, 1.12-.86]). DOAC nonadherence was associated with an increased risk of stroke (hazard ratio, 1.39 [95% CI, 1.06-1.81]).

CONCLUSIONS

Suboptimal adherence and persistence to DOACs was common in patients with AF, with 1 in 3 patients adhering to their DOAC <80% of the time, which was associated with poor clinical outcomes in nonadherent patients. Although it is convenient that DOACs do not require laboratory monitoring, greater effort in monitoring for and interventions to prevent nonadherence may be necessary to optimize stroke prevention. Increased clinician awareness of DOAC nonadherence may help identify at-risk patients.

Predicting Cost-Effectiveness of Generic vs. Brand Dabigatran Using Pharmacometric Estimates Among Patients with Atrial Fibrillation in the United States

Generic entry of newer anticoagulants is expected to decrease the costs of atrial fibrillation management. However, when making switches between brand and generic medications, bioequivalence concerns are possible. The objectives of this study were to predict and compare the lifetime cost‐effectiveness of brand dabigatran with hypothetical future generics. Markov microsimulations were modified to predict the lifetime costs and quality‐adjusted life years of patients on either brand or generic dabigatran from a US private payer perspective. Event rates for generics were predicted using previously developed pharmacokinetic‐pharmacodynamic models. The analyses showed that generic dabigatran with lower‐than‐brand systemic exposure were dominant. Meanwhile, generic dabigatran with extremely high systemic exposure was not cost‐effective compared with the brand reference. Cost‐effectiveness of generic medications cannot always be assumed as shown in this example. Combined use of pharmacometric and pharmacoeconomic models can assist in decision making between brand and generic pharmacotherapies.

Use of insertable cardiac monitors for the detection of atrial fibrillation in patients with cryptogenic stroke in the United States is cost-effective

Objectives: Atrial fibrillation (AF) is the most common arrhythmia and a major marker of ischemic stroke risk. Early detection is crucial and, once diagnosed, anticoagulation therapy can be initiated to reduce stroke risk. The aim of this study was to assess the cost-effectiveness of employing an insertable cardiac monitor (ICM), BIOMONITOR, for the detection of AF compared to standard of care (SoC) ECG and Holter monitoring in patients with cryptogenic stroke, that is, stroke of unknown origin and where paroxysmal, silent AF is suspected. Materials and methods: A Markov model was developed which consisted of five main health states reflecting the potential lifetime evolution of the AF disease: post cryptogenic stroke (index event), subsequent mild, moderate and severe stroke, and death. Sub-states were included to track a patient's AF diagnostic status and the use of antiplatelet or anticoagulant therapy. AF detection was assumed to result in a treatment switch from aspirin to anticoagulants, except among those with a history of major bleeding. Detection yield and accuracy, clinical actions and treatment effects were derived from the literature and validated by an expert clinician. All relevant costs from a US Medicare perspective were included. Results and conclusions: An ICM-based strategy was associated with a reduction of 37 secondary ischemic strokes per 1000 patients monitored compared with SoC. Total per-patient costs with an ICM were higher (US$90,052 vs. US$85,157) although stroke-related costs were reduced. The use of an ICM was associated with a base-case incremental cost-effectiveness ratio of US$18,487 per life year gained compared with SoC and US$25,098 per quality-adjusted life year gained, below established willingness-to-pay thresholds. The conclusions were found to be robust over a range of input values. From a US Medicare perspective the use of a BIOMONITOR ICM represents a cost-effective diagnostic strategy for patients with cryptogenic stroke and suspected AF.

Effectiveness and safety of betrixaban extended prophylaxis for venous thromboembolism compared with standard-duration prophylaxis intervention in acute medically ill patients: a systematic literature review and network meta-analysis

Aims: To determine the clinical effectiveness and safety of venous thromboembolism (VTE) prophylaxis using US- and Europe-approved anticoagulants relative to extended-duration VTE prophylaxis with betrixaban. Low molecular weight heparins (LMWHs), unfractionated heparin (UFH), fondaparinux sodium and placebo were each compared to betrixaban, as standard-duration VTE prophylaxis for hospitalized, non-surgical patients with acute medical illness at risk of VTE. Materials and methods: A systematic literature review was conducted up to June 2019 to identify randomized controlled trials (RCTs) of VTE prophylaxis in hospitalized, non-surgical patients with acute medical illness at risk of VTE. Studies that reported the occurrence of VTE events (including death) and, where possible, major bleeding, from treatment initiation to 20-50 days thereafter were retrieved and extracted. A Bayesian fixed effect network meta-analysis was used to estimate efficacy and safety of betrixaban compared with standard-duration VTE prophylaxis. Results: Seven RCTs were analyzed which compared betrixaban, LMWHs, UFH, fondaparinux sodium, or placebo. There were significantly higher odds (median odds [95% credible interval]) of VTE with LMWHs (1.38 [1.12-1.70]), UFH (1.60 [1.05-2.46]), and placebo (2.37 [1.55-3.66]) compared with betrixaban. There were significantly higher odds of VTE-related death with placebo (7.76 [2.14-34.40]) compared with betrixaban. No significant differences were observed for the odds of major bleeding with all comparators, VTE-related death with any active standard-duration VTE prophylaxis, or of VTE with fondaparinux sodium, compared with betrixaban. Limitations and conclusions: In this indirect comparison, betrixaban was shown to be an effective regimen with relative benefits compared with LMWHs and UFH. This indicates that betrixaban could reduce the burden of VTE in at-risk hospitalized patients with acute medical illness who need extended prophylaxis, though without direct comparative evidence, stronger conclusions cannot be drawn.

Directly Acting Oral Anticoagulants for the Prevention of Stroke in Atrial Fibrillation in England and Wales: Cost-Effectiveness Model and Value of Information Analysis

Objectives. Determine the optimal, licensed, first-line anticoagulant for prevention of ischemic stroke in patients with non-valvular atrial fibrillation (AF) in England and Wales from the UK National Health Service (NHS) perspective and estimate value to decision making of further research. Methods. We developed a cost-effectiveness model to compare warfarin (international normalized ratio target range 2-3) with directly acting (or non-vitamin K antagonist) oral anticoagulants (DOACs) apixaban 5 mg, dabigatran 150 mg, edoxaban 60 mg, and rivaroxaban 20 mg, over 30 years post treatment initiation. In addition to death, the 17-state Markov model included the events stroke, bleed, myocardial infarction, and intracranial hemorrhage. Input parameters were informed by systematic literature reviews and network meta-analysis. Expected value of perfect information (EVPI) and expected value of partial perfect information (EVPPI) were estimated to provide an upper bound on value of further research. Results. At willingness-to-pay threshold £20,000, all DOACs have positive expected incremental net benefit compared to warfarin, suggesting they are likely cost-effective. Apixaban has highest expected incremental net benefit (£7533), followed by dabigatran (£6365), rivaroxaban (£5279), and edoxaban (£5212). There was considerable uncertainty as to the optimal DOAC, with the probability apixaban has highest net benefit only 60%. Total estimated population EVPI was £17.94 million (17.85 million, 18.03 million), with relative effect between apixaban versus dabigatran making the largest contribution with EVPPI of £7.95 million (7.66 million, 8.24 million). Conclusions. At willingness-to-pay threshold £20,000, all DOACs have higher expected net benefit than warfarin but there is considerable uncertainty between the DOACs. Apixaban had the highest expected net benefit and greatest probability of having highest net benefit, but there is considerable uncertainty between DOACs. A head-to-head apixaban versus dabigatran trial may be of value.

Cost-Effectiveness Analysis of Direct-Acting Oral Anticoagulants for Stroke Prevention in Thai Patients with Non-Valvular Atrial Fibrillation and a High Risk of Bleeding

OBJECTIVE

The objective of this study was to assess the cost effectiveness of direct-acting oral anticoagulants for stroke prevention in Thai patients with non-valvular atrial fibrillation and a HAS-BLED score of 3.

METHODS

Total costs (US$) in 2017 and quality-adjusted life-years were estimated over 20 years using a Markov model. A base-case analysis was conducted under a societal perspective, which included direct healthcare, non-healthcare and indirect costs in Thailand. Clinical events for warfarin and utilities were obtained from Thai patients whenever possible. The efficacy of direct-acting oral anticoagulants was derived from trial-based East Asian subgroups and adjusted for time in the target international normalized ratio range of warfarin.

RESULTS

In the base case, use of apixaban instead of warfarin incurred an additional cost of US$20,763 per quality-adjusted life-year gained. Substituting apixaban with rivaroxaban and rivaroxaban with high-dose edoxaban would incur an additional cost per quality-adjusted life-year by US$507 and US$434, respectively. Compared with warfarin, high-dose edoxaban had the lowest incremental cost-effectiveness ratio of US$9704/quality-adjusted life-year, followed by high-dose dabigatran (incremental cost-effectiveness ratio US$11,155/quality-adjusted life-year). The incremental cost-effectiveness ratios based on a payer perspective were similar. The incremental cost-effectiveness ratio was below Thailand's cost-effectiveness threshold when high-dose dabigatran and edoxaban prices were reduced by 50%. Changes in key parameters had a minimal impact on incremental cost-effectiveness ratios.

CONCLUSIONS

For both societal and payer perspectives, high-dose edoxaban with a price below the country cost-effectiveness threshold should be the first anticoagulant option for Thai patients with non-valvular atrial fibrillation and a high risk of bleeding.

Cost-Utility Analysis of Apixaban versus Warfarin in Atrial Fibrillation Patients with Chronic Kidney Disease

BACKGROUND

Warfarin use for stroke prevention in atrial fibrillation (AF) patients with chronic kidney disease is debated. Apixaban was shown to be safer than warfarin, with superior reduction in the risk of stroke, systemic embolism, mortality, and major bleeding irrespective of kidney function.

OBJECTIVES

To evaluate the cost-utility of apixaban compared with warfarin in AF patients at different levels of kidney function.

METHODS

A Markov model was used to estimate the cost effectiveness of apixaban compared with warfarin in AF patients at three levels of kidney function: estimated glomerular filtration rate (eGFR) of more than 80 ml/min, 50 to 80 ml/min, and 50 ml/min or less. Event rates and associated utilities were obtained from previous literature. The model adopted the US health care system perspective, with hospitalization costs extracted from the Healthcare and Utilization Project. Treatment costs were obtained from official price lists. Univariate and probabilistic sensitivity analyses were performed to evaluate the robustness of results.

RESULTS

Apixaban was a dominant treatment strategy compared with warfarin in AF patients with eGFR levels of 50 ml/min or less and 50 to 80 ml/min. In patients with an eGFR of more than 80 ml/min, apixaban was cost-effective compared with warfarin, costing $6307 per quality-adjusted life-year gained. Results were consistent assuming anticoagulant discontinuation after major bleeding events. Compared with dabigatran and rivaroxaban, apixaban was the only cost-effective anticoagulant strategy relative to warfarin in both mild and moderate renal impairment settings.

CONCLUSIONS

Apixaban is a favorably cost-effective alternative to warfarin in AF patients with normal kidney function and potentially cost-saving in those with renal impairment.

Annual costs attributed to atrial fibrillation management: cross-sectional study of primary healthcare electronic records

Atrial fibrillation (AF) is the most common chronic arrhythmia, with increasing healthcare and economic burden and a prevalence which increases with progressive ageing. This study aims to describe overall annual costs per patient for management of non-valvular AF in a primary healthcare (PHC) setting and compare these costs between the groups of patients treated with vitamin K antagonists, antiplatelets or non-treated through a population-based study conducted with electronic health records. We analysed annual costs per person of 19,787 patients in 2012; PHC visits, hospital admissions, AF-related events requiring hospital admission, referrals to secondary specialists, sick leave, diagnostic tests and laboratory tests at PHC level, including INR determinations performed in PHC, and drug therapy. Higher costs of AF management were associated with increasing age, male sex, stroke and bleeding risks, comorbidities and occurrence of events associated to AF. The sensitivity analyses conducted showed that PHC visits and hospitalizations represented the most important part of overall costs for all patients.

TIMI-AF score and cardiovascular events in vitamin K antagonists-naïve outpatients with atrial fibrillation

BACKGROUND

The TIMI-AF score predicts poor outcomes in patients with atrial fibrillation (AF) and guides selection of anticoagulant therapy by identifying clinical benefit of direct oral anticoagulants (DOACs) or vitamin K antagonists (VKA).

HYPOTHESIS

Our objective was to determine the ability to predict cardiovascular events according to the TIMI-AF score in a real-world population.

METHODS

Retrospective observational study of VKA-naïve patients with AF was seen at a cardiology outpatient clinic in Spain between November 2012 and August 2014. We recorded adverse events (myocardial infarction, systemic embolism or stroke, major bleeding, and death).

RESULTS

The study population comprised of 426 patients (50.7% men, mean age, 69 ± 14 years). The TIMI-AF score identified 372 patients (87.3%) with a low risk, 50 patients (11.7%) with an intermediate risk, and 4 patients (0.9%) with a high risk. After a mean follow-up of 423.4 ± 200.1 days, 37 patients (9%) experienced an adverse event. Patients with a TIMI-AF score ≥ 7 had a poorer cardiovascular prognosis (HR, 6.1; 95%CI, 3.2-11.7; P < 0.001). The area under the ROC curve of TIMI-AF was 0.755 (95%CI, 0.669-0.840; P < 0.001), which was greater than that of CHA₂ DS₂ VASc (0.641; 95%CI, 0.559-0.724; P = 0.004), HAS-BLED (0.666; 95%CI, 0.578-0.755; P < 0.001), and SAMeTT₂ R₂ (0.529; 95%CI, 0.422-0.636; P = 0.565). Similar results were obtained in relation to the net clinical outcome (life-threatening bleeding, disabling stroke, or all-cause mortality).

CONCLUSIONS

The TIMI-AF risk score can identify patients who are at greater risk of cardiovascular events and a poor net clinical outcome with a better diagnostic yield than CHA₂ DS₂ VASc, HAS-BLED, and SAMeTT₂ R₂ .

Cost-Effectiveness of Patent Foramen Ovale Closure Versus Medical Therapy for Secondary Stroke Prevention

BACKGROUND AND PURPOSE

Percutaneous transcatheter closure of patent foramen ovale (PFO closure) plus antiplatelet therapy has been shown to reduce the risk of recurrent stroke compared with medical therapy alone in carefully selected patients after cryptogenic stroke presumed to be from paradoxical embolism. Our objective was to determine the cost-effectiveness of PFO closure after cryptogenic stroke compared with conservative medical management from a US healthcare payer perspective.

METHODS

A decision analytic Markov model estimated the 15-year cost and outcomes associated with the additional benefit of PFO closure compared with medical management alone. Model inputs were obtained from published literature, national databases, and a meta-analysis of 5 published randomized clinical trials on PFO closure. Health outcomes were measured in quality-adjusted life years (QALY). Cost-effectiveness used the incremental cost per QALY gained, whereas the net monetary benefit assumed a willingness to pay of $150 000/QALY. One-way and probabilistic sensitivity analyses estimated the uncertainty of model results.

RESULTS

At 15 years, PFO closure compared with medical therapy alone improved QALY by 0.33 at a cost saving of $3568, representing an incremental net monetary benefit of $52 761 (95% interval -$8284 to $158 910). When the meta-analysis hazard ratio for stroke was increased to the 95% interval's upper bound of 0.77, one-way sensitivity analyses suggested that PFO closure's cost-effectiveness was $458 558 per additional QALY. Probabilistic sensitivity analysis suggested cost-effectiveness in 90% of simulation runs.

CONCLUSIONS

PFO closure for cryptogenic strokes in the right setting is cost-effective, producing benefit in QALYs gained and potential cost savings. However, patient selection remains vitally important as marginal declines in treatment effectiveness can dramatically affect cost-effectiveness.

Association of Intracerebral Hemorrhage Among Patients Taking Non-Vitamin K Antagonist vs Vitamin K Antagonist Oral Anticoagulants With In-Hospital Mortality

IMPORTANCE

Although non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used to prevent thromboembolic disease, there are limited data on NOAC-related intracerebral hemorrhage (ICH).

OBJECTIVE

To assess the association between preceding oral anticoagulant use (warfarin, NOACs, and no oral anticoagulants [OACs]) and in-hospital mortality among patients with ICH.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of 141 311 patients with ICH admitted from October 2013 to December 2016 to 1662 Get With The Guidelines-Stroke hospitals.

EXPOSURES

Anticoagulation therapy before ICH, defined as any use of OACs within 7 days prior to hospital arrival.

MAIN OUTCOMES AND MEASURES

In-hospital mortality.

RESULTS

Among 141 311 patients with ICH (mean [SD] age, 68.3 [15.3] years; 48.1% women), 15 036 (10.6%) were taking warfarin and 4918 (3.5%) were taking NOACs preceding ICH, and 39 585 (28.0%) and 5783 (4.1%) were taking concomitant single and dual antiplatelet agents, respectively. Patients with prior use of warfarin or NOACs were older and had higher prevalence of atrial fibrillation and prior stroke. Acute ICH stroke severity (measured by the National Institutes of Health Stroke Scale) was not significantly different across the 3 groups (median, 9 [interquartile range, 2-21] for warfarin, 8 [2-20] for NOACs, and 8 [2-19] for no OACs). The unadjusted in-hospital mortality rates were 32.6% for warfarin, 26.5% for NOACs, and 22.5% for no OACs. Compared with patients without prior use of OACs, the risk of in-hospital mortality was higher among patients with prior use of warfarin (adjusted risk difference [ARD], 9.0% [97.5% CI, 7.9% to 10.1%]; adjusted odds ratio [AOR], 1.62 [97.5% CI, 1.53 to 1.71]) and higher among patients with prior use of NOACs (ARD, 3.3% [97.5% CI, 1.7% to 4.8%]; AOR, 1.21 [97.5% CI, 1.11-1.32]). Compared with patients with prior use of warfarin, patients with prior use of NOACs had a lower risk of in-hospital mortality (ARD, -5.7% [97.5% CI, -7.3% to -4.2%]; AOR, 0.75 [97.5% CI, 0.69 to 0.81]). The difference in mortality between NOAC-treated patients and warfarin-treated patients was numerically greater among patients with prior use of dual antiplatelet agents (32.7% vs 47.1%; ARD, -15.0% [95.5% CI, -26.3% to -3.8%]; AOR, 0.50 [97.5% CI, 0.29 to 0.86]) than among those taking these agents without prior antiplatelet therapy (26.4% vs 31.7%; ARD, -5.0% [97.5% CI, -6.8% to -3.2%]; AOR, 0.77 [97.5% CI, 0.70 to 0.85]), although the interaction P value (.07) was not statistically significant.

CONCLUSIONS AND RELEVANCE

Among patients with ICH, prior use of NOACs or warfarin was associated with higher in-hospital mortality compared with no OACs. Prior use of NOACs, compared with prior use of warfarin, was associated with lower risk of in-hospital mortality.

Advances in anticoagulation therapy

Because atrial fibrillation (AF) is a major risk for thrombotic disease, many patients with AF are managed with anticoagulation for primary or secondary prevention of these events. The emergence of novel oral anticoagulants offers patients and providers options to consider beyond warfarin. Decision making should address safety, tolerability, efficacy, price, and simplicity of use; and decisions should be individualized for each patient.

Nonpharmacist Health Care Providers' Knowledge of and Opinions Regarding Medication Costs in Critically Ill Patients

Purpose: Medication cost is frequently overlooked when treating critically ill patients. Stewardship of health care resources in high-utilization settings is imperative. This study was conducted to determine nonpharmacist health care providers' knowledge and perceptions of medication costs in a medical intensive care unit (MICU). Methods: Nonpharmacist health care providers in a MICU completed a 27-item survey. The survey queried perceptions regarding medication cost, cost-limiting strategies, and most/least expensive medications in 8 classes, medication price ranges, and intravenous-to-oral comparisons for commonly prescribed medications. Responses were analyzed using descriptive statistics and compared between providers using Fisher exact tests. Results: Among 98 health care providers (76 medical trainees, 5 attending physicians, 17 nurses), when ordering a medication, 49% consider its cost. Few (15%) providers considered themselves knowledgeable regarding medication costs with no difference between providers (P = .174). Attending physicians were more aware of the most/least expensive medications than residents (correct out of 16: 9.6 vs 8.5, P = .044). The correct price ranges for select medications (11%-36%, P = .373) and intravenous-to-oral relative costs (3%-49%, P = .596) were similarly low. Most (59%) believed pharmacists limit expensive medication use, particularly senior physicians (58% resident vs 100% attending, P = .007). Conclusion: In spite of a goal of cost consideration, most nonpharmacist health care providers are unaware of medication costs and fail to include them in decision making. These knowledge gaps and perceptions should inform future efforts to improve knowledge and attitudes regarding medication costs.

Evaluation of bleeding in patients receiving direct oral anticoagulants

Direct oral anticoagulants (DOACs) are recognized by evidence-based treatment guidelines as the first-line option for the treatment of venous thromboembolism and prevention of stroke and systemic embolism in nonvalvular atrial fibrillation. As use of these anticoagulants has become favored over the past several years, reported bleeding-related adverse drug events with these agents has increased. In randomized clinical trials, all DOACs have a reduced risk for intracranial hemorrhage, while major and other bleeding results have varied among the agents compared to vitamin K antagonists. We have reviewed the bleeding incidence and severity from randomized and real-world data in patients receiving DOACs in an effort to provide the clinician with a critical review of bleeding and offer practical considerations for avoiding adverse events with these anticoagulants.

Edoxaban: How Does the Newest Agent Fit into the DOAC Landscape?

Edoxaban is the most recently approved factor Xa inhibitor within the class of direct oral anticoagulants (DOACs). Like other DOACs, edoxaban was approved by the US Food and Drug Administration for treatment of venous thromboembolism and prevention of stroke in patients with nonvalvular atrial fibrillation. Similar to other DOACs, edoxaban has fewer drug-drug interactions than warfarin and does not require routine laboratory monitoring. Unlike other DOACs, edoxaban has yet to be approved for secondary or postoperative venous thromboembolism thromboprophylaxis. Currently no antidote for edoxaban is available. To optimally prescribe agents in the DOAC class, it is critical that providers 1) understand how the agents compare; and 2) identify specific settings in which one agent may be preferred over another.

Cost-effectiveness of non-vitamin K antagonist oral anticoagulants for stroke prevention in patients with atrial fibrillation at high risk of bleeding and normal kidney function

INTRODUCTION

The comparative cost-effectiveness of all oral anticoagulants approved up to date has not been evaluated from the US perspective. The objective of this study was to compare the cost-effectiveness of edoxaban 60mg, apixaban 5mg, dabigatran 150mg, dabigatran 110mg, rivaroxaban 20mg and warfarin in stroke prevention in atrial fibrillation patients at high-risk of bleeding (defined as HAS-BLED score≥3).

MATERIALS AND METHODS

We constructed a Markov state-transition model to evaluate lifetime costs and quality-adjusted life years (QALYs) with each of the six treatments from the perspective of US third-party payers. Probabilities of clinical events were obtained from the RE-LY, ROCKET-AF, ARISTOTLE and ENGAGE AF-TIMI trials; costs were derived from the Healthcare Cost and Utilization Project, and other studies. Because edoxaban is only indicated in patients with creatinine clearance ≤95ml/min, we re-ran our analyses after excluding edoxaban from the analysis.

RESULTS

Treatment with edoxaban 60mg cost $77,565/QALY gained compared to warfarin, and apixaban 5mg cost $108,631/QALY gained compared to edoxaban 60mg. When edoxaban was not included in the analysis, treatment with apixaban 5mg cost $84,128/QALY gained, compared to warfarin. Dabigatran 150mg, dabigatran 110mg and rivaroxaban 20mg were dominated strategies.

CONCLUSIONS

For patients with creatinine clearance between 50 and 95ml/min, apixaban 5mg was the most cost-effective treatment for willingness-to-pay thresholds (WTP) above $115,000/QALY gained, and edoxaban 60mg was cost-effective when the WTP was between $75,000 and $115,000/QALY gained. For patients with creatinine clearance >95ml/min, apixaban 5mg was the most cost-effective treatment for WTP thresholds above $80,000/QALY gained.