Cost-Effectiveness of Dabigatran Compared With Warfarin for Stroke Prevention in Patients With Atrial Fibrillation and Prior Stroke or Transient Ischemic Attack

Cost-Effectiveness of Screening Asymptomatic Carotid Stenosis by Atherosclerotic Cardiovascular Risk

Importance

Extracranial internal carotid artery stenosis (50-99% arterial narrowing) is an important risk factor for ischemic stroke. Yet, the benefits and harms of targeted screening for asymptomatic carotid artery stenosis (ACAS) have not been assessed in population-based studies.

Objective

To estimate the cost-effectiveness of one-time, targeted ACAS screening stratified by atherosclerotic cardiovascular disease (ASCVD) risk using the American Heart Association's Pooled Cohort Equations.

Design Setting and Participants

We developed a lifetime microsimulation model of ACAS and stroke for a hypothetical cohort representative of US adults aged 50-80 years without stroke history. We used the Cardiovascular Health Study to estimate the probability and severity of ACAS based on individual characteristics (e.g., age, sex, smoking status, blood pressure, and cholesterol). Stroke risks were functions of these characteristics and ACAS severity. In the model, individuals testing positive for >70% stenosis with Duplex ultrasound and a confirmatory diagnostic test undergo revascularization, which may reduce the risk of stroke but also introduces complication risks. Diagnostic performance parameters, revascularization benefits and risks, utility weights, and costs were estimated from published sources. Cost-effectiveness was assessed from the health care sector perspective using a $100,000/quality-adjusted life year (QALY) threshold.

Main Outcomes and Measures

Estimated stroke events prevented, lifetime costs, QALYs, and incremental cost-effectiveness ratios (ICERs) associated with ACAS screening. Costs (2023 USD) and QALYs were discounted at 3% annually.

Results

We found that screening individuals with a 10-year ASCVD risk >30% was the most cost-effective strategy, with an ICER of $89,000/QALY. This strategy would make approximately 11.9% of the population eligible for screening, averting an estimated 24,084 strokes. Results were sensitive to variations in the efficacy and complication risk of revascularization. In probabilistic sensitivity analysis, screening those in lower ASCVD risk groups (0-20%) only had a 0.6% chance of being cost-effective.

Conclusion and Relevance

A one-time screening may only be cost-effective for adults at a relatively high ASCVD risk. Our findings provide a framework that can be adapted as future clinical trial data continue to improve our understanding of the role of revascularization and intensive medical therapy in contemporary stroke prevention secondary to carotid disease.

Cost-Effectiveness of Increased Use of Dual Antiplatelet Therapy After High-Risk Transient Ischemic Attack or Minor Stroke

BACKGROUND

Rates of dual antiplatelet therapy (DAPT) after high-risk transient ischemic attack or minor ischemic stroke (TIAMIS) are suboptimal. We performed a cost-effectiveness analysis to characterize the parameters of a quality improvement (QI) intervention designed to increase DAPT use after TIAMIS.

METHODS AND RESULTS

We constructed a decision tree model that compared current national rates of DAPT use after TIAMIS with rates after implementing a theoretical QI intervention designed to increase appropriate DAPT use. The base case assumed that a QI intervention increased the rate of DAPT use to 65% from 45%. Costs (payer and societal) and outcomes (stroke, myocardial infarction, major bleed, or death) were modeled using a lifetime horizon. An incremental cost-effectiveness ratio <$100 000 per quality-adjusted life year was considered cost-effective. Deterministic and probabilistic sensitivity analyses were performed. From the payer perspective, a QI intervention was associated with $9657 in lifetime cost savings and 0.18 more quality-adjusted life years compared with current national treatment rates. A QI intervention was cost-effective in 73% of probabilistic sensitivity analysis iterations. Results were similar from the societal perspective. The maximum acceptable, initial, 1-time payer cost of a QI intervention was $28 032 per patient. A QI intervention that increased DAPT use to at least 51% was cost-effective in the base case.

CONCLUSIONS

Increasing DAPT use after TIAMIS with a QI intervention is cost-effective over a wide range of costs and proportion of patients with TIAMIS treated with DAPT after implementation of a QI intervention. Our results support the development of future interventions focused on increasing DAPT use after TIAMIS.

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 Smoking Cessation Interventions in Patients With Ischemic Stroke and Transient Ischemic Attack

BACKGROUND

Smoking cessation rates after stroke and transient ischemic attack are suboptimal, and smoking cessation interventions are underutilized. We performed a cost-effectiveness analysis of smoking cessation interventions in this population.

METHODS

We constructed a decision tree and used Markov models that aimed to assess the cost-effectiveness of varenicline, any pharmacotherapy with intensive counseling, and monetary incentives, compared with brief counseling alone in the secondary stroke prevention setting. Payer and societal costs of interventions and outcomes were modeled. The outcomes were recurrent stroke, myocardial infarction, and death using a lifetime horizon. Estimates and variance for the base case (35% cessation), costs and effectiveness of interventions, and outcome rates were imputed from the stroke literature. We calculated incremental cost-effectiveness ratios and incremental net monetary benefits. An intervention was considered cost-effective if the incremental cost-effectiveness ratio was less than the willingness-to-pay threshold of $100 000 per quality-adjusted life-year (QALY) or when the incremental net monetary benefit was positive. Probabilistic Monte Carlo simulations modeled the impact of parameter uncertainty.

RESULTS

From the payer perspective, varenicline and pharmacotherapy with intensive counseling were associated with more QALYs (0.67 and 1.00, respectively) at less total lifetime costs compared with brief counseling alone. Monetary incentives were associated with 0.71 more QALYs at an additional cost of $120 compared with brief counseling alone, yielding an incremental cost-effectiveness ratio of $168/QALY. From the societal perspective, all 3 interventions provided more QALYs at less total costs compared with brief counseling alone. In 10 000 Monte Carlo simulations, all 3 smoking cessation interventions were cost-effective in >89% of runs.

CONCLUSIONS

For secondary stroke prevention, it is cost-effective and potentially cost-saving to deliver smoking cessation therapy beyond brief counseling alone.

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 Screening for Paroxysmal Atrial Fibrillation in Patients undergoing Echocardiography

OBJECTIVE

To compare the cost-effectiveness of unselected electrocardiographic (ECG) screening for atrial fibrillation (AF), and selective screening based on an abnormal echocardiogram.

METHODS

Two strategies of portable ECG screening for AF were compared in the base case of a hypothetical asymptomatic 65-year-old man (CHA₂ DS₂ -VASC=3 based on hypertension and diabetes mellitus) with previous echocardiography but without a cause for AF (eg. mitral valve disease, LV dysfunction). With age-based screening (AgeScreen, 3% AF detection rate) all patients underwent ECG. With imaging-guided screening (ImagingScreen; 5% detection rate), only patients with left atrial volume (LA) ≥34ml/m² and LA reservoir strain <34% or LV global longitudinal strain (GLS)>-18% underwent ECG screening. A Markov model was informed by published transition probabilities, costs and quality-adjusted life years (QALY). Costs, effects and incremental cost-effectiveness ratio (ICER) were assessed for each screening strategy over a 20 year period. The willingness-to-pay threshold was $53,000/QALY.

RESULTS

ImagingScreen dominated AgeScreen, with a lower cost ($54,823 vs $57,842) and better outcome (11.56 vs 11.52 QALY over 20 years). Monte Carlo simulation demonstrated that 61% of observations were more efficacious with ImagingScreen, with cost below willingness-to-pay. The main cost determinants were annual costs of stroke or heart failure and AF detection rates. ImagingScreen was more cost-effective for AF detection rates up to 14%, and more cost-effective across a range of annual stroke ($24,000-$102,000) and heart failure ($4,000-$12,000) costs.

CONCLUSION

In patients with a previous echocardiogram, AF screening of those with baseline clinical and imaging risk parameters is more cost-effective than age-based screening. This article is protected by copyright. All rights reserved.

Comparative Clinical Outcomes of Edoxaban in Adults With Nonvalvular Atrial Fibrillation

BACKGROUND

A critical appraisal of all pooled evidence regarding novel oral anticoagulants (NOACs) for stroke prevention regardless of publication status or study design has not been conducted yet. Being the latest addition to NOACs, the data on edoxaban are especially scarce.

STUDY QUESTION

What are the comparative clinical outcomes of edoxaban versus warfarin and other NOACs apixaban, dabigatran, or rivaroxaban in adults with nonvalvular atrial fibrillation?

DATA SOURCES

Randomized controlled trials (RCTs), observational studies, and network meta-analyses were identified in PubMed, EMBASE, the Cochrane Library, Pharmapendium, Elsevier Clinical Pharmacology, and the clinicaltrials.gov trial registry in June 2018.

STUDY DESIGN

Rapid review per a priori developed protocol, direct frequentist random-effects meta-analysis of aggregate data, grading the quality of evidence per the Grading of Recommendations Assessment, Development and Evaluation working group approach.

RESULTS

Direct 4 RCTs (23,021 patients) suggest that edoxaban is noninferior to warfarin in prevention of stroke and systemic embolism [pooled relative risk (RR): 0.65, 95% confidence interval (CI): 0.23-1.81, 2 RCTs] and reduces the risk of cardiovascular mortality (RR: 0.87, 95% CI: 0.78-0.97, 1 RCT), major cardiovascular morbidity (RR: 0.90, 95% CI: 0.82-0.98, 2 RCTs), and major bleeding events (RR: 0.80, 95% CI: 0.71-0.91, 1 RCT) but increases the risk of gastrointestinal bleeding (RR: 1.21, 95% CI: 1.01-1.46, 1 RCT) and anemia (RR: 1.45, 95% CI: 1.05-1.99, 3 RCTs). Edoxaban is superior to warfarin in patients with increased risk of bleeding with warfarin because of variants in CYP2C9 and VKORC1 genes. Indirect evidence does not allow valid conclusions regarding comparative superiority of NOACs. The quality of evidence was downgraded because of reporting bias, small number of events, and indirectness in comparisons.

CONCLUSIONS

Edoxaban is a welcome addition to the NOAC's armamentarium. However, the comparative data with other novel NOACs are mostly nonexisting, and urgently needed for better individual patient assessment.

Cost-Effectiveness of Left Atrial Appendage Closure With the WATCHMAN Device Compared With Warfarin or Non-Vitamin K Antagonist Oral Anticoagulants for Secondary Prevention in Nonvalvular Atrial Fibrillation

Supplemental Digital Content is available in the text.

Background and Purpose—

Once a patient with atrial fibrillation experiences an embolic event, the risk of a recurrent event increases 2.6-fold. New treatments have emerged as viable treatment alternatives to warfarin for stroke risk reduction in secondary prevention populations. This analysis sought to assess the cost-effectiveness of left atrial appendage closure (LAAC) compared with warfarin and the non–vitamin K antagonist oral anticoagulants dabigatran 150 mg, apixaban and rivaroxaban in the prevention of stroke in nonvalvular atrial fibrillation patients with a prior stroke or transient ischemic attack.

Methods—

A Markov model was constructed using data from the secondary prevention subgroup analyses of the non–vitamin K antagonist oral anticoagulant and LAAC pivotal trials. Costs were from 2016 US Medicare reimbursement rates and the literature. The cost-effectiveness analysis was conducted from a US Medicare perspective over a lifetime (20 years) horizon. The model was populated with a cohort of 10 000 patients aged 70 years with a CHA₂DS₂-VASc score of 7 (annual stroke risk=9.60%) and HAS-BLED score of 3 (annual bleeding risk=3.74%).

Results—

LAAC achieved cost-effectiveness relative to dabigatran at year 5 and warfarin and apixaban at year 6. At 10 years, LAAC had more quality-adjusted life years (4.986 versus 4.769, 4.869, 4.888, and 4.810) and lower costs ($42 616 versus $53 770, $58 774, $55 656, and $58 655) than warfarin, dabigatran, apixaban, and rivaroxaban, respectively, making LAAC the dominant (more effective and less costly) stroke risk reduction strategy. LAAC remained the dominant strategy over the lifetime analysis.

Conclusions—

Upfront procedure costs initially make LAAC higher cost than warfarin and the non–vitamin K antagonist oral anticoagulants, but within 10 years, LAAC delivers more quality-adjusted life years and has lower total costs, making LAAC the most cost-effective treatment strategy for secondary prevention of stroke in atrial fibrillation.

Oral anticoagulants for primary prevention, treatment and secondary prevention of venous thromboembolic disease, and for prevention of stroke in atrial fibrillation: systematic review, network meta-analysis and cost-effectiveness analysis

BACKGROUND

Warfarin is effective for stroke prevention in atrial fibrillation (AF), but anticoagulation is underused in clinical care. The risk of venous thromboembolic disease during hospitalisation can be reduced by low-molecular-weight heparin (LMWH): warfarin is the most frequently prescribed anticoagulant for treatment and secondary prevention of venous thromboembolism (VTE). Warfarin-related bleeding is a major reason for hospitalisation for adverse drug effects. Warfarin is cheap but therapeutic monitoring increases treatment costs. Novel oral anticoagulants (NOACs) have more rapid onset and offset of action than warfarin, and more predictable dosing requirements.

OBJECTIVE

To determine the best oral anticoagulant/s for prevention of stroke in AF and for primary prevention, treatment and secondary prevention of VTE.

DESIGN

Four systematic reviews, network meta-analyses (NMAs) and cost-effectiveness analyses (CEAs) of randomised controlled trials.

SETTING

Hospital (VTE primary prevention and acute treatment) and primary care/anticoagulation clinics (AF and VTE secondary prevention).

PARTICIPANTS

Patients eligible for anticoagulation with warfarin (stroke prevention in AF, acute treatment or secondary prevention of VTE) or LMWH (primary prevention of VTE).

INTERVENTIONS

NOACs, warfarin and LMWH, together with other interventions (antiplatelet therapy, placebo) evaluated in the evidence network.

MAIN OUTCOME MEASURES

Efficacy Stroke, symptomatic VTE, symptomatic deep-vein thrombosis and symptomatic pulmonary embolism. Safety Major bleeding, clinically relevant bleeding and intracranial haemorrhage. We also considered myocardial infarction and all-cause mortality and evaluated cost-effectiveness.

DATA SOURCES

MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The Cochrane Library, reference lists of published NMAs and trial registries. We searched MEDLINE and PREMEDLINE In-Process & Other Non-Indexed Citations, EMBASE and The Cochrane Library. The stroke prevention in AF review search was run on the 12 March 2014 and updated on 15 September 2014, and covered the period 2010 to September 2014. The search for the three reviews in VTE was run on the 19 March 2014, updated on 15 September 2014, and covered the period 2008 to September 2014.

REVIEW METHODS

Two reviewers screened search results, extracted and checked data, and assessed risk of bias. For each outcome we conducted standard meta-analysis and NMA. We evaluated cost-effectiveness using discrete-time Markov models.

RESULTS

Apixaban (Eliquis^®, Bristol-Myers Squibb, USA; Pfizer, USA) [5 mg bd (twice daily)] was ranked as among the best interventions for stroke prevention in AF, and had the highest expected net benefit. Edoxaban (Lixiana^®, Daiichi Sankyo, Japan) [60 mg od (once daily)] was ranked second for major bleeding and all-cause mortality. Neither the clinical effectiveness analysis nor the CEA provided strong evidence that NOACs should replace postoperative LMWH in primary prevention of VTE. For acute treatment and secondary prevention of VTE, we found little evidence that NOACs offer an efficacy advantage over warfarin, but the risk of bleeding complications was lower for some NOACs than for warfarin. For a willingness-to-pay threshold of > £5000, apixaban (5 mg bd) had the highest expected net benefit for acute treatment of VTE. Aspirin or no pharmacotherapy were likely to be the most cost-effective interventions for secondary prevention of VTE: our results suggest that it is not cost-effective to prescribe NOACs or warfarin for this indication.

CONCLUSIONS

NOACs have advantages over warfarin in patients with AF, but we found no strong evidence that they should replace warfarin or LMWH in primary prevention, treatment or secondary prevention of VTE.

LIMITATIONS

These relate mainly to shortfalls in the primary data: in particular, there were no head-to-head comparisons between different NOAC drugs.

FUTURE WORK

Calculating the expected value of sample information to clarify whether or not it would be justifiable to fund one or more head-to-head trials.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005324, CRD42013005331 and CRD42013005330.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Neuroinflammatory response to experimental stroke is inhibited by boldine

Inflammation plays a pivotal role in the development of ischemic brain damage. Astrocyte activation promotes the production of several proinflammatory mediators, such as TNF-α and iNOS. Eventually, neuronal death occurs, leading to the development of motor and memory deficits in patients. Boldine is the main alkaloid in the leaves and bark of the Peumus boldus Molina, and has anti-inflammatory and antioxidant properties. The aim of this work was to investigate the neuroprotective effect of boldine on neuroinflammation and memory deficits induced by permanent middle cerebral artery occlusion (pMCAO) in mice. Thirty minutes before pMCAO and during the next 5 days, animals received vehicle (0.025 µmol/l HCl) or boldine (8, 16 and 25 mg/kg, intraperitoneally). The extension of the infarct area, neurological scores, and myeloperoxidase activity were evaluated 24 h after pMCAO. Locomotor activity, working, and aversive memory were evaluated 72 h after pMCAO, object recognition memory was tested 96 h after pMCAO, and spatial memory was tested 120 h after pMCAO. Cresyl violet, Fluoro-Jade C staining, and immunohistochemical for GFAP, TNF-α, and iNOS were also carried out. The treatment with boldine significantly decreased the infarct area, improved the neurological scores, and increased cell viability. The vertical exploratory activity and aversive, spatial, object recognition, and working memory deficits induced by pMCAO were prevented by boldine. Moreover, myeloperoxidase activity and GFAP, TNF-α, and iNOS immunoreactivity were decreased significantly by boldine. Although various mechanisms such as its antioxidant activity should be considered, these results suggest that the neuroprotective effect of boldine might be related in part to its anti-inflammatory properties.

Dabigatran versus rivaroxaban for the prevention of stroke and systemic embolism in atrial fibrillation in Canada

Canadian patients with atrial fibrillation (AF) in whom anticoagulation is appropriate have two new choices for anticoagulation for prevention of stroke and systemic embolism – dabigatran etexilate (dabigatran) and rivaroxaban. Based on the RE-LY and ROCKET AF trial results, we investigated the cost-effectiveness of dabigatran (twice daily dosing of 150 mg or 110 mg based on patient age) versus rivaroxaban from a Canadian payer perspective. A formal indirect treatment comparison (ITC) of dabigatran versus rivaroxaban was performed, using dabigatran clinical event rates from RE-LY for the safety-on-treatment population, adjusted to the ROCKET AF population. A previously described Markov model was modified to simulate anticoagulation treatment using ITC results as inputs. Model outputs included total costs, event rates, and quality-adjusted life-years (QALYs). The ITC found when compared to rivaroxaban, dabigatran had a lower risk of intracranial haemorrhage (ICH) (relative risk [RR] = 0.38; 95% confidence interval [CI] 0.21 –0.67) and stroke (RR = 0.62; 95%CI 0.45–0.87). Over a lifetime horizon, the model found dabigatran-treated patients experienced fewer ICHs (0.33 dabigatran vs. 0.71 rivaroxaban) and ischaemic strokes (3.40 vs. 3.96) per 100 patient-years, and accrued more QALYs (6.17 vs. 6.01). Dabigatran-treated patients had lower acute care and long-term follow-up costs per patient ($52,314 vs. $53,638) which more than offset differences in drug costs ($7,299 vs. $6,128). In probabilistic analysis, dabigatran had high probability of being the most cost-effective therapy at common thresholds of willingness-to-pay (93% at a $20,000/QALY threshold). This study found dabigatran is economically dominant versus rivaroxaban for prevention of stroke and systemic embolism among Canadian AF patients.

Healthcare utilization and costs for patients initiating Dabigatran or Warfarin

Background

Novel oral anticoagulants (NOAC) such as dabigatran, when compared to warfarin, have been shown to potentially reduce the risk of stroke in patients with non-valvular atrial fibrillation (NVAF) together with lower healthcare resource utilization (HCRU) and similar total costs. This study expands on previous work by comparing HCRU and costs for patients newly diagnosed with NVAF and newly initiated on dabigatran or warfarin, and is the first study specifically in a Medicare population.

Methods

A retrospective matched-cohort study was conducted using data from administrative health care claims during the study period 01/01/2010–12/31/2012. Cox regression analyses were used to compare all-cause risk of first hospitalizations and emergency room (ER) visits. Medical, pharmacy, and total costs per-patient-per-month (PPPM) were compared between dabigatran and warfarin users.

Results

A total of 1110 patients initiated on dabigatran were propensity score-matched with corresponding patients initiated on warfarin. The mean number of hospitalizations (0.92 vs. 1.13, P = 0.012), ER visits (1.32 vs. 1.56, P < 0.01), office visits (21.43 vs. 29.41; P < 0.01), and outpatient visits (10.86 vs. 22.02; P < 0.01) were lower among dabigatran compared to warfarin users. Patients initiated on dabigatran had significantly lower risk of first all-cause ER visits [hazard ratio (HR): 0.84, 95% confidence interval (CI): 0.73–0.98] compared to those initiated on warfarin. Adjusted mean pharmacy costs PPPM were significantly greater for dabigatran users ($510 vs. $250, P < 0.001); however, mean medical costs PPPM ($1912 vs. $1956, P = 0.55) and mean total costs PPPM ($2381 vs. $2183, P = 0.10) were not significantly different compared to warfarin users.

Conclusions

Dabigatran users had significantly lower HCRU compared to warfarin users. In addition, dabigatran users had lower risk of all-cause ER visits. Despite higher pharmacy costs, the two cohorts did not differ significantly in medical or total all-cause costs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12955-017-0705-x) contains supplementary material, which is available to authorized users.

Nonvitamin-K-antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and previous stroke or transient ischemic attack: An updated systematic review and meta-analysis of randomized controlled trials

Background

In a previous systematic review and meta-analysis, we assessed the efficacy and safety of nonvitamin-K antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and stroke or transient ischemic attack. Since then, new information became available.

Aim

The aim of the present work was to update the results of the previous systematic review and meta-analysis.

Methods

We searched PubMed until 24 August 2016 for randomized controlled trials using the following search items: “atrial fibrillation” and “anticoagulation” and “warfarin” and “previous stroke or transient ischemic attack.” Eligible studies had to be phase III trials in patients with atrial fibrillation comparing warfarin with nonvitamin-K antagonist oral anticoagulants currently on the market or with the intention to be brought to the market in North America or Europe. The outcomes assessed in the efficacy analysis included stroke or systemic embolism, stroke, ischemic or unknown stroke, disabling or fatal stroke, hemorrhagic stroke, cardiovascular death, death from any cause, and myocardial infarction. The outcomes assessed in the safety analysis included major bleeding, intracranial bleeding, and major gastrointestinal bleeding. We performed fixed effects analyses on intention-to-treat basis.

Results

Among 183 potentially eligible articles, four were included in the meta-analysis. In 20,500 patients, compared to warfarin, nonvitamin-K antagonist oral anticoagulants were associated with a significant reduction of stroke/systemic embolism (relative risk reduction: 13.7%, absolute risk reduction: 0.78%, number needed to treat to prevent one event: 127), hemorrhagic stroke (relative risk reduction: 50.0%, absolute risk reduction: 0.63%, number needed to treat: 157), any stroke (relative risk reduction: 13.1%, absolute risk reduction: 0.7%, number needed to treat: 142), and intracranial hemorrhage (relative risk reduction: 46.1%, absolute risk reduction: 0.88%, number needed to treat: 113) over 1.8–2.8 years.

Conclusions

This updated meta-analysis in 20,500 atrial fibrillation patients with previous stroke or transient ischemic attack shows that compared to warfarin non-vitamin-K antagonist oral anticoagulants are associated with a significant reduction of stroke, stroke or systemic embolism, hemorrhagic stroke, and intracranial bleeding.

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.

A cost-utility analysis for catheter ablation of atrial fibrillation in combination with warfarin and dabigatran based on the CHADS2 score in Japan

BACKGROUND

We aimed to clarify the cost-effectiveness of an expensive combination therapy for atrial fibrillation (AF) using both catheter ablation and dabigatran compared with warfarin at each CHADS₂ score for patients in Japan.

METHODS

A Markov model was constructed to analyze costs and quality-adjusted life years associated with AF therapeutic options with a time horizon of 10 years. The target population was 60-year-old patients with paroxysmal AF. The indication for anticoagulation was determined according to the Japanese guideline. Anticoagulation-related data were derived from the RE-LY study and the AF recurrence rate was set at 2.7% per month during the first 12 months and at 0.40% per month afterwards. Stroke risk was determined according to AF recurrence, anticoagulation, and CHADS₂ score. The risks for stroke recurrence and stroke death were also considered. Costs were calculated from the healthcare payer's perspective, and only direct medical costs were included.

RESULTS

Warfarin was the most preferred option for patients with a CHADS₂ score of 0 from a health economics aspect. Ablation under warfarin was preferred for a CHADS₂ score of 1-3, while ablation under dabigatran was preferred for a CHADS₂ score ≥4. The quality of life score for AF had the largest impact on the incremental cost-effectiveness ratios in the analysis between the anticoagulation arm and the anticoagulation+ablation arm for a CHADS₂ score of 2. Within the range of the Japanese willingness-to-pay threshold (¥5,000,000), the ablation+warfarin arm became the best option with its probability of 81.7% for a CHADS₂ score of 2; the dabigatran+ablation arm was the most preferred option with its probability of 56.1% for a CHADS₂ score of 4.

CONCLUSIONS

Ablation under dabigatran therapy is an expensive therapeutic option, but it might benefit patients with a low quality of life and a high CHADS₂ score.

Cost-Effectiveness of Dabigatran (150 mg Twice Daily) and Warfarin in Patients ≥ 65 Years With Nonvalvular Atrial Fibrillation

Dabigatran has been shown to be superior to warfarin for stroke prevention in nonvalvular atrial fibrillation (NVAF) but with higher out-of-pocket costs for patients. Although dabigatran has been shown to be cost effective from a societal perspective, cost implications for individual patients and insurers are not well described. We aimed to assess cost perspectives of each payer (Medicare and patient) in relation to administration, monitoring, and adverse outcomes for dabigatran and warfarin in patients with and without prescription drug coverage. Using a Markov model, we performed a decision analysis comparing 2 treatment strategies (dose-adjusted warfarin and dabigatran 150 mg twice daily) in patients 65 years old with NVAF, CHADS2 scores ≥ 1, and Medicare insurance. Patients have a quality-adjusted life expectancy of 8.998 quality-adjusted life years with warfarin and 9.39 quality-adjusted life years with dabigatran 150 mg twice daily. From Medicare's perspective, the incremental cost-effectiveness ratio comparing dabigatran with warfarin was $35,311 for patients with Part D coverage and cost saving for patients without coverage. From the patient's perspective, the incremental cost-effectiveness ratio comparing dabigatran with warfarin was cost saving for patients with Part D coverage and $63,884 for those without coverage. In patients ≥ 65 years with NVAF and prescription insurance coverage, dabigatran 150 mg twice daily is both cost effective (Medicare's perspective) and cost saving (patient perspective) compared with warfarin, at a willingness-to-pay threshold of $100,000. However, patients without prescription drug coverage have a high out-of-pocket cost burden with dabigatran therapy, leading to a reduction in its cost-effectiveness compared with warfarin therapy. In conclusion, this Markov model suggests that Medicare Part D coverage influences the cost-effectiveness of dabigatran 150 mg daily compared with dose-adjusted warfarin from multiple payer perspectives.

Personalized medicine and stroke prevention: where are we?

There are many recommended pharmacological and non-pharmacological therapies for the prevention of stroke, and an ongoing challenge is to improve their uptake. Personalized medicine is seen as a possible solution to this challenge. Although the use of genetic information to guide health care could be considered as the apex of personalized medicine, genetics is not yet routinely used to guide prevention of stroke. Currently personalized aspects of prevention of stroke include tailoring interventions based on global risk, the utilization of individualized management plans within a model of organized care, and patient education. In this review we discuss the progress made in these aspects of prevention of stroke and present a case study to illustrate the issues faced by health care providers and patients with stroke that could be overcome with a personalized approach to the prevention of stroke.

Healthcare utilization and costs associated with dabigatran compared to warfarin treatment in newly diagnosed patients with non-valvular atrial fibrillation

PURPOSE

Real-world healthcare resource utilization and costs were compared among patients with non-valvular atrial fibrillation (NVAF) receiving either dabigatran or warfarin.

METHODS

A retrospective cohort study was conducted using administrative claims data from the United States Department of Defense (DOD) Military Health System. Patients with newly diagnosed AF initiated on dabigatran or warfarin were identified using ICD-9 diagnosis, procedure and drug codes. Patients were observed for 3 months prior to treatment initiation to ascertain a diagnosis of valvular heart disease and 12 months for exclusion of those with a history of anticoagulation therapy. Propensity score matching was used to balance baseline characteristics between the two treatment cohorts. Medical and pharmacy utilization and costs were compared between the dabigatran and warfarin treatment groups for 3 and 12 months following treatment initiation.

RESULTS

A total of 1102 patients with newly diagnosed NVAF initiated on dabigatran were matched with corresponding warfarin-treated patients. In the 12 months following initiation of anticoagulation, the mean medical costs for patients initiated on dabigatran were significantly lower than for patients initiated on warfarin (-$6299, p < 0.001), largely due to fewer hospitalizations (-0.162, p = 0.009). While pharmacy costs were higher ($4369, p < 0.001) for dabigatran, overall healthcare costs were significantly lower compared with patients on warfarin (12 months: -$1940, p < 0.001). Mean hospital length of stay between these two groups were similar (6.033 days for dabigatran vs 6.318 days for warfarin, p = 0.139).

CONCLUSION

Despite higher pharmacy costs for NVAF patients initiated on dabigatran vs warfarin, this was more than offset by lower utilization of medical care resources.

Cost-Effectiveness and Cost-Utility Analyses of Dabigatran Compared with Warfarin in Patients with Nonvalvular Atrial Fibrillation and Risk Factors for Stroke and Systemic Embolism within Brazilian Private and Public Health Care Systems Perspectives

OBJECTIVE

To analyze the cost-effectiveness and cost-utility of dabigatran compared with warfarin in patients with nonvalvular atrial fibrillation with moderate to high risk of ischemic stroke or systemic embolism and eligible for treatment with anticoagulants.

METHODS

Markov-based economic analysis was performed to estimate treatment costs and outcomes. Epidemiological and efficacy data were determined after a critical revision of the medical literature. Unit costs were taken from Brazilian official databases. Only direct medical costs were covered. Costs and benefits were discounted at a rate of 5% per year. Outcomes were expressed as life-year (LY) and quality-adjusted life-year (QALY).

RESULTS

Dabigatran use is cost-effective in terms of LY and QALY considering a willingness-to-pay threshold of 3 times gross domestic product per capita of 2010 (Brazilian real 57,048/US $24,275.74) per LY and QALY saved in both analyzed perspectives (private and public health care systems).

CONCLUSIONS

Dabigatran use improves patient survival and quality of life compared with warfarin. This represents the best therapeutic option in terms of cost and effectiveness in the prevention of ischemic stroke and systemic embolism in patients with nonvalvular atrial fibrillation.

Hospital costs associated with atrial fibrillation for patients with ischemic stroke aged 18-64 years in the United States

BACKGROUND AND PURPOSE

Hospital costs associated with atrial fibrillation (AFib) among patients with stroke have not been well-studied, especially among people aged <65 years. We estimated the AFib-associated hospital costs in US patients aged 18 to 64 years.

METHODS

We identified hospital admissions with a primary diagnosis of ischemic stroke from the 2010 to 2012 MarketScan Commercial Claims and Encounters inpatient data sets, excluding those with capitated health insurance plans, aged <18 or >64 years, missing geographic region, hospital costs below the 1st or above 99th percentile, and having carotid intervention (n=40 082). We searched the data for AFib and analyzed the costs for nonrepeat and repeat stroke admissions separately. We estimated the AFib-associated costs using multivariate regression models controlling for age, sex, geographic region, and Charlson comorbidity index.

RESULTS

Of the 33 500 nonrepeat stroke admissions, 2407 (7.2%) had AFib. Admissions with AFib cost $4991 more than those without AFib ($23 770 versus $18 779). For the 6582 repeat stroke admissions, 397 (6.0%) had AFib. The costs were $3260 more for those with AFib than those without ($24 119 versus $20 929). After controlling for potential confounders, AFib-associated costs for nonrepeat stroke admissions were $4905, representing 20.6% of the total costs for the admissions. Both the hospital costs and the AFib-associated costs were associated with age, but not with sex. AFib-associated costs for repeat stroke admissions were not significantly higher than for non-AFib patients, except for those aged 55 to 64 years ($3537).

CONCLUSIONS

AFib increased the hospital cost of ischemic stroke substantially. Further investigation on AFib-associated costs for repeat stroke admissions is needed.

Cost of acute stroke care for patients with atrial fibrillation compared with those in sinus rhythm

BACKGROUND

Atrial fibrillation (AF) is a major risk factor for stroke. Cost-effectiveness studies of anticoagulants for stroke prevention in AF rarely utilise AF-stroke-specific cost data in their analyses, as data are limited. Data that exist do not account for AF found on prolonged cardiac monitoring after stroke, further underestimating the clinical and economic burden of AF-stroke.

OBJECTIVE

Our objective was to investigate differences in direct medical costs of acute stroke care among patients with and without AF.

METHODS

Data were prospectively collected from 213 consecutive patients with confirmed stroke (196 ischaemic [IS], 17 intracranial haemorrhage [ICH]), admitted to a UK district general hospital between November 2011 and October 2012. Sociodemographic, clinical and cardiac monitoring characteristics were recorded, and resource use was calculated using a 'bottom-up' approach. Univariate and multivariate stepwise regressions were performed to identify predictors of direct cost.

RESULTS

Among patients with IS, 73 had AF (37%). These patients were older, experienced greater stroke severity, lengths of hospitalisation, inpatient mortality and discharge to institutionalised care than those without AF. Mean acute care costs for the year 2012 were £6,978 (standard deviation [SD] 6,769, range 510-36,952). Mean (SD) costs were significantly higher for patients with AF than for those without (£9,083 [7,381] vs. £5,729 [6,071], p = <0.001). AF independently predicted acute care cost along with history of heart failure and stroke severity. The adjusted independent effect of having AF on costs was an additional £2,173 (95% confidence interval 91-4,254; p = 0.041). Costs for patients with an ICH did not differ according to cardiac rhythm.

CONCLUSION

Direct medical costs of acute stroke care for patients with AF may be 50% greater than for patients without. Economic studies should take this into account to ensure the benefits of anticoagulants are not underestimated.

Dabigatran for the prevention and treatment of thromboembolic disorders

Dabigatran, an oral direct thrombin inhibitor, was the first of a new class of drugs referred to as non-vitamin K oral anticoagulants. Dabigatran is better than warfarin for stroke prevention in non-valvular atrial fibrillation (dose of 150 mg twice a day), non-inferior to enoxaparin for venous thromboembolism prevention after orthopedic surgery and non-inferior to warfarin in preventing recurrence after acute venous thromboembolism. The safety profile is similar to standard anticoagulants, with significant reduction observed in intracranial hemorrhage. Other advantages include a rapid onset of action and a predictable pharmacokinetic profile, allowing a fixed-dose regimen without the need for routine anticoagulation monitoring. In the event of bleeding, general support measures are recommended and if severe, the use of non-specific hemostatic agents such as prothrombin complex concentrates and recombinant factor VIIa must be considered. A specific reversal agent (idarucizumab) is in development.

Systematic review of cost-effectiveness analyses of novel oral anticoagulants for stroke prevention in atrial fibrillation

INTRODUCTION AND OBJECTIVES

Novel oral anticoagulants are emerging options for the prevention and treatment of thromboembolic diseases. They are increasingly used in clinical practice due to their simplicity of use and clinical benefits, but an important step is to evaluate their cost-effectiveness. The aim of the AFFORD study (A Review of Cost EFFectiveness of Novel ORal Anticoagulant Drugs) was to perform a systematic review of cost-effectiveness studies of novel oral anticoagulants for stroke prevention in non-valvular atrial fibrillation (AF).

METHODS

A systematic review of the literature was conducted by searching the PubMed, Embase, Scopus, Cochrane and Web of Knowledge databases to identify all cost-effectiveness studies of novel oral anticoagulants for stroke prevention in AF.

RESULTS

The search identified 27 studies, 18 with dabigatran, three with apixaban, two with rivaroxaban and four with at least two of these drugs. The incremental cost-effectiveness ratios were 30 405 ± 16 101 euros per quality-adjusted life-year (QALY) for dabigatran 110 mg, 17 566 ± 16 902 euros/QALY for dabigatran 150 mg, 8102 ± 3252 euros/QALY for age-adjusted dabigatran, 11 897 ± 3341 euros/QALY for apixaban and 17 960 ± 12 005 euros/QALY for rivaroxaban.

CONCLUSION

The present systematic review demonstrates that novel oral anticoagulants are cost-effective for stroke prevention in AF.

Comparison of cost-effectiveness of anticoagulation with dabigatran, rivaroxaban and apixaban in patients with non-valvular atrial fibrillation across countries

We did a cost-utility analysis for the new oral anticoagulants (NOACs) in the German population based on the quality-adjusted life years (QALY), total costs, and incremental cost-effectiveness ratios (ICER). The aim of our investigation was to examine cost-utility for current German drug market costs and compared to other countries. Outcome data were taken from dabigatran's RE-LY, rivaroxaban's ROCKET AF, and apixaban's ARISTOTLE trials. A Markov decision model, the Monte Carlo simulation (MCS), and further sensitivity analyses were used to simulate comparisons between NOACs over a follow up period of 20 years. The main perspective used for the analyses is from a German public health care insurance perspective. The base-case analyses of a 65 years old person with a CHADS2 score >1 resulted in 7.56-7.64 QALYs gained for warfarin. NOACs added 0.04-0.19 QALYs. Total costs for warfarin ranged from 7622 to 9069<euro> and for NOACs from 19537 to 20048<euro>. The sensitivity analysis indicated that current German market costs for the NOACs exceed a willingness-to-pay threshold of (hypothetical) 50000<euro>/QALY in all treatment regimen. The MCS showed willingness-to-pay thresholds from 60500<euro>/QALY for apixaban to 278000<euro>/QALY for dabigatran 110 mg bid, with values for dabigatran 150 mg bid and rivaroxaban in between. In conclusion, from a German public health care insurance perspective current market costs are high in relation to the quality of life gained. These results from clinical studies (efficacy) remain to be confirmed under real life conditions (effectiveness).

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Cost-Effectiveness of Angiographic Imaging in Isolated Perimesencephalic Subarachnoid Hemorrhage

Background and Purpose—

The purpose of this study is to perform a comprehensive cost-effectiveness analysis of all possible permutations of computed tomographic angiography (CTA) and digital subtraction angiography imaging strategies for both initial diagnosis and follow-up imaging in patients with perimesencephalic subarachnoid hemorrhage on noncontrast CT.

Methods—

Each possible imaging strategy was evaluated in a decision tree created with TreeAge Pro Suite 2014, with parameters derived from a meta-analysis of 40 studies and literature values. Base case and sensitivity analyses were performed to assess the cost-effectiveness of each strategy. A Monte Carlo simulation was conducted with distributional variables to evaluate the robustness of the optimal strategy.

Results—

The base case scenario showed performing initial CTA with no follow-up angiographic studies in patients with perimesencephalic subarachnoid hemorrhage to be the most cost-effective strategy ($5422/quality adjusted life year). Using a willingness-to-pay threshold of $50 000/quality adjusted life year, the most cost-effective strategy based on net monetary benefit is CTA with no follow-up when the sensitivity of initial CTA is >97.9%, and CTA with CTA follow-up otherwise. The Monte Carlo simulation reported CTA with no follow-up to be the optimal strategy at willingness-to-pay of $50 000 in 99.99% of the iterations. Digital subtraction angiography, whether at initial diagnosis or as part of follow-up imaging, is never the optimal strategy in our model.

Conclusions—

CTA without follow-up imaging is the optimal strategy for evaluation of patients with perimesencephalic subarachnoid hemorrhage when modern CT scanners and a strict definition of perimesencephalic subarachnoid hemorrhage are used. Digital subtraction angiography and follow-up imaging are not optimal as they carry complications and associated costs.

Cost-effectiveness of different strategies for stroke prevention in patients with atrial fibrillation in a health resource-limited setting

PURPOSE

To compare the lifetime cost and effectiveness of five alternative chronic atrial fibrillation (AF) management strategies: rivaroxaban, warfarin, aspirin plus clopidogrel, aspirin and no prevention.

METHODS

An individual-level state-transition model was developed to track the lifetime disease course associated with AF. The clinical and utility data were derived from published studies. The cost data were estimated based on local charges and current Chinese practices. Sensitivity analyses were used to explore the impact of uncertainty on the results.

RESULTS

For base-case patients with a CHADS2 score of 3, the cost per additional quality-adjusted life-years (QALYs) gained for rivaroxaban compared with no prevention, aspirin, aspirin plus clopidogrel and warfarin was $116,884, $153,944, $155,979 and $216,273, respectively. CHADS2 score had a substantial impact on the model outcomes for different prevention strategies. The time distribution of warfarin international normalised ratio (INR), stroke and intracranial haemorrhage (ICH) risks, cost of rivaroxaban and utility of warfarin therapy had substantial impacts on the results. Based on a willingness-to-pay threshold of $16,350/QALY, no prevention strategy was the preferred therapy for a patient with a low risk for stroke and a high risk for ICH; aspirin was preferred for patients with a moderate risk for stroke and ICH; and warfarin was preferred for patients with a high risk for stroke and a low risk of ICH.

CONCLUSION

In the context of limited health resources, rivaroxaban is unlikely to be cost-effective, although it provided more health benefits comparing with other strategies. Additionally, warfarin with good INR control might be more suitable for AF patients in developing regions.

Cost-effectiveness of dabigatran versus vitamin K antagonists for the prevention of stroke in patients with atrial fibrillation: a French payer perspective

BACKGROUND

Atrial fibrillation is the main cause of stroke, but the risk can be reduced, usually with vitamin K antagonists (VKAs) such as warfarin. The RE-LY atrial fibrillation study demonstrated that the rates of stroke and systemic embolism with dabigatran (an oral direct thrombin inhibitor) were similar to or lower than those with warfarin.

AIMS

To estimate the cost-effectiveness, from a French payer perspective, of dabigatran (150 or 110mg bid for patients<or≥80 years, respectively) versus warfarin.

METHODS

Cost-effectiveness was modeled using a Markov model in a cohort of 10,000 patients with atrial fibrillation followed over their lifetime. Events accounted for included ischemic stroke, systemic embolism, transient ischemic attack, hemorrhage, myocardial infarction and death. The model patient population matched the RE-LY patients. Dabigatran was compared with "trial-like" warfarin and "real-world" prescribing. Risks of clinical events were obtained from RE-LY. Event and follow-up costs were based on the French national tariff or published literature. Clinical events, QALYs, total costs and incremental cost-effectiveness ratios (ICERs) were calculated.

RESULTS

The ICERs of dabigatran compared with "trial-like" warfarin and "real-world" prescribing were €15,838/QALY and €7473/QALY, respectively. Deterministic and probabilistic sensitivity analyses showed these to be robust to uncertainty and variability in the model parameters. The ICER for dabigatran was below €24,000/QALY or €36,000/QALY in 71% or 92%, respectively, of the simulations when compared with "trial-like" warfarin and 100% and 100%, respectively, when compared with "real-world" prescribing.

CONCLUSION

This study suggests that the use of dabigatran in French atrial fibrillation patients is cost-effective, according to usually accepted thresholds.

New oral anticoagulants may be particularly useful for asian stroke patients

Atrial fibrillation (AF) is an emerging epidemic in both high-income and low-income countries, mainly because of global population aging. Stroke is a major complication of AF, and AF-related ischemic stroke is more disabling and more fatal than other types of ischemic stroke. However, because of concerns about bleeding complications, particularly intracranial hemorrhage, and the limitations of a narrow therapeutic window, warfarin is underused. Four large phase III randomized controlled trials in patients with non-valvular AF (RE-LY, ROCKET-AF, ARISTOTLE, and ENGAGE-AF-TIMI 48) demonstrated that new oral anticoagulants (NOACs) are superior or non-inferior to warfarin as regards their efficacy in preventing ischemic stroke and systemic embolism, and superior to warfarin in terms of intracranial hemorrhage. Among AF patients receiving warfarin, Asians compared to non-Asians are at higher risk of stroke or systemic embolism and are also more prone to develop major bleeding complications, including intracranial hemorrhage. The extra benefit offered by NOACs over warfarin appears to be greater in Asians than in non-Asians. In addition, Asians are less compliant, partly because of the frequent use of herbal remedies. Therefore, NOACs compared to warfarin may be safer and more useful in Asians than in non-Asians, especially in stroke patients. Although the use of NOACs in AF patients is rapidly increasing, guidelines for the insurance reimbursement of NOACs have not been resolved, partly because of insufficient understanding of the benefit of NOACs and partly because of cost concerns. The cost-effectiveness of NOACs has been well demonstrated in the healthcare settings of developed countries, and its magnitude would vary depending on population characteristics as well as treatment cost. Therefore, academic societies and regulatory authorities should work together to formulate a scientific healthcare policy that will effectively reduce the burden of AF-related stroke in this rapidly aging society.

Cost-effectiveness of apixaban versus other new oral anticoagulants for stroke prevention in atrial fibrillation

BACKGROUND

Apixaban (5 mg BID), dabigatran (available as 150 mg and 110 mg BID in Europe), and rivaroxaban (20 mg once daily) are 3 novel oral anticoagulants (NOACs) currently approved for stroke prevention in patients with atrial fibrillation (AF).

OBJECTIVE

The objective of this study was to evaluate the cost-effectiveness of apixaban against other NOACs from the perspective of the United Kingdom National Health Services.

METHODS

A Markov model was developed to evaluate the pharmacoeconomic impact of apixaban versus other NOACs over a lifetime. Pair-wise indirect treatment comparisons were conducted against other NOACs by using ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation), RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy), and ROCKET-AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation) trial results for the following end points: ischemic stroke, hemorrhagic stroke, intracranial hemorrhage, other major bleeds, clinically relevant nonmajor bleeds, myocardial infarction, and treatment discontinuations. Outcomes were life-years, quality-adjusted life years gained, direct health care costs, and incremental cost-effectiveness ratios.

RESULTS

Apixaban was projected to increase life expectancy versus other NOACs, including dabigatran (both doses) and rivaroxaban. A small increase in therapeutic management costs was observed with apixaban due to projected gains in life expectancy and lower discontinuation rates anticipated on apixaban versus other NOACs through lifetime. The estimated incremental cost-effectiveness ratio was £9611, £4497, and £5305 per quality-adjusted life-year gained with apixaban compared with dabigatran 150 mg BID, dabigatran 110 mg BID, and rivaroxaban 20 mg once daily, respectively. Sensitivity analyses indicated that results were robust over a wide range of inputs.

CONCLUSIONS

Although our analysis was limited by the absence of head-to-head trials, based on the indirect comparison data available, our model projects that apixaban may be a cost-effective alternative to dabigatran 150 mg BID, dabigatran 110 mg BID, and rivaroxaban 20 mg once daily for stroke prevention in AF patients from the perspective of the United Kingdom National Health Services.

Application of personalized medicine to chronic disease: a feasibility assessment

Personalized Medicine has the potential to improve health outcomes and reduce the cost of care; however its adoption has been slow in Canada. Bridgepoint Health is a complex continuous care provider striving to reduce the burden of polypharmacy in chronic patients. The main goal of the study was to explore the feasibility of utilizing personalized medicine in the treatment of chronic complex patients as a preliminary institutional health technology assessment. We analyzed stroke treatment optimization as a clinical indication that could serve as a "proof of concept" for the widespread implementation of pharmacogenetics. The objectives of the study were three-fold:1. Review current practice in medication administration for stroke treatment at Bridgepoint Health2. Critically analyze evidence that pharmacogenetic testing could (or could not) enhance drug selection and treatment efficacy for stroke patients;3. Assess the cost-benefit potential of a pharmacogenetic intervention for stroke.Review current practice in medication administration for stroke treatment at Bridgepoint HealthCritically analyze evidence that pharmacogenetic testing could (or could not) enhance drug selection and treatment efficacy for stroke patients;Assess the cost-benefit potential of a pharmacogenetic intervention for stroke.We conducted a review of stroke treatment practices at Bridgepoint Health, scanned the literature for drug-gene and drug-outcome interactions, and evaluated the potential consequences of pharmacogenetic testing using the ACCE model.There is a substantial body of evidence suggesting that pharmacogenetic stratification of stroke treatment can improve patient outcomes in the long-term, and provide substantial efficiencies for the healthcare system in the short-term. Specifically, pharmacogenetic stratification of antiplatelet and anticoagulant therapies for stroke patients may have a major impact on the risk of disease recurrence, and thus should be explored further for clinical application. Bridgepoint Health, and other healthcare institutions taking this path, should consider launching pilot projects to assess the practical impact of pharmacogenetics to optimize treatment for chronic continuous care.

Advances and challenges in treatment and prevention of ischemic stroke

We review recent advances in the treatment and prevention of acute ischemic stroke, including the current state of endovascular therapy, in light of 5 randomized controlled trials published this past year. Although no benefit of endovascular therapy over intravenous (IV) recombinant tissue plasminogen activator (rt-PA) has been demonstrated, endovascular therapy is an appropriate treatment for acute ischemic stroke patients within the t-PA window who are ineligible for IV t-PA but have a large vascular occlusion. These trials reveal promises and current limitations of endovascular therapy, and comparison of reperfusion therapies remains an important area of research. One common theme is the strong association between a faster time to reperfusion, improved outcome, and reduced mortality. Primary and secondary stroke prevention trials emphasize the importance of aggressive management of medical risk factors as part of any preventative strategy. New oral anticoagulants, for example, offer cost-effective risk reduction in patients with atrial fibrillation, and may represent an opportunity for those with cryptogenic stroke. We highlight areas of unmet need and promising research in stroke, including the need to deliver proven therapies to more patients, and the need to recruit patients into clinical trials that better define the role of endovascular and other stroke therapies. Finally, improvement in strategies to recover speech, cognition, and motor function has the potential to benefit far more stroke patients than any acute stroke therapy, and represents the greatest opportunity for research in the coming century.

Cost-effectiveness of oral anticoagulants for treatment of atrial fibrillation

BACKGROUND

New anticoagulants may improve health outcomes in patients with atrial fibrillation, but it is unclear whether their use is cost-effective.

METHODS AND RESULTS

A Markov state transition was created to compare 4 therapies: dabigatran 150 mg BID, apixaban 5 mg BID, rivaroxaban 20 mg QD, and warfarin therapy. The population included those with newly diagnosed atrial fibrillation who were eligible for treatment with warfarin. Compared with warfarin, apixaban, rivaroxaban, and dabigatran, costs were $93 063, $111 465, and $140 557 per additional quality-adjusted life year gained, respectively. At a threshold of $100 000 per quality-adjusted life year, apixaban provided the greatest absolute benefit while still being cost-effective, although warfarin would be superior if apixaban was 2% less effective than expected. Although apixaban was the optimal strategy in our base case, in probabilistic sensitivity analysis, warfarin was optimal in an equal number of iterations at a cost-effectiveness threshold of $100 000 per quality-adjusted life year.

CONCLUSIONS

While at a standard cost-effectiveness threshold of $100 000 per quality-adjusted life year, apixaban seems to be the optimal anticoagulation strategy; this finding is sensitive to assumptions about its efficacy and cost. In sensitivity analysis, warfarin seems to be the optimal choice in an equal number of simulations. As a result, although all the novel oral anticoagulants produce greater quality-adjusted life expectancy than warfarin, they may not represent good value for money.

Use of novel oral anticoagulants for patients with atrial fibrillation: systematic review and clinical implications

Atrial fibrillation (AF), a common arrhythmia, increases the risk of ischemic stroke. Stroke and bleeding scores for patients with AF can help to stratify risk and determine the need for antithrombotic therapy, for which warfarin has been the gold standard. Although highly effective, warfarin has several limitations that can lead to its underuse. Data from randomized, Phase III clinical trials of the novel oral anticoagulants, dabigatran, a direct thrombin inhibitor, and rivaroxaban and apixaban, both factor Xa inhibitors, indicate these drugs are at least noninferior to warfarin for the prevention of stroke and systemic embolism. They are easier to administer, and have an equivalent or lower risk of bleeding versus warfarin. A better understanding of the risks and benefits of the novel oral anticoagulants, and their use in clinical practice, will prepare clinicians to anticipate and address educational and clinical needs of AF patients and their families, and promote evidence-based prescription of appropriate and safe anticoagulation therapy.

Cost effectiveness of treatments for stroke prevention in atrial fibrillation: focus on the novel oral anticoagulants

For more than 5 decades, the only available treatment for the prevention of atrial fibrillation (AF)-related stroke were the vitamin K antagonists. Recently, novel oral anticoagulants (NOAC) have been approved for the prevention of AF-related stroke. In the present article, the cost effectiveness of AF-related stroke-prevention strategies is reviewed. The emphasis on NOACs aims to provide an overview of their impact on health economics based on the published cost-effectiveness analyses. The available evidence suggests that the balance from the efficacy and safety point of view makes the treatment with the NOACs a cost-effective alternative to warfarin. Thus, the NOACs offer efficacy, safety and convenience, as well as cost effectiveness, for stroke prevention in AF.

Factors influencing doctors' selection of dabigatran in non-valvular atrial fibrillation

RATIONALE, AIMS AND OBJECTIVES

This study was designed to examine the factors that influence doctors' decision in initiating or switching from warfarin to dabigratran.

METHOD

A survey questionnaire was sent to 181 doctors who were most likely to prescribe dabigatran (e.g. cardiologists and general internists) at the University of California, San Francisco Medical Center between November 2011 and February 2012. Survey participants were asked to complete an electronic or a paper version of the questionnaire, which consisted of 17 multiple-choice questions. Fisher's exact test and Cochran-Mantel-Haenszel test were used to compare survey responses between cardiologists and general internists.

RESULTS

A total of 65 survey responses were received (35.9% response rate). There were 13 cardiologists and 51 general internists who participated in the study. Cost (25%), renal function (21%) and CHADS2 score (18%) were the three factors doctors considered most often to determine a patient's eligibility for dabigatran in warfarin-naïve patients. On the other hand, histories of unstable international normalized ratio (37%) and missed appointments (17%) along with cost (19%) were most often considered in patients on warfarin. Cardiologists had prescribed dabigatran more often and had a significantly higher level of comfort with prescribing the drug than general internists (P = 0.003; 77% vs. 27%).

CONCLUSIONS

Cost was the most important factor influencing doctors' decision to prescribe dabigatran. Safety and effectiveness of dabigatran as well as patient preference were additional factors influencing their decision. General internists were less comfortable with prescribing dabigatran than cardiologists.

A review of apixaban for stroke prevention in atrial fibrillation: insights from ARISTOTLE

Atrial fibrillation (AF) is associated with significant mortality and morbidity, and stroke represents the most-feared complication. Consequently, AF treatment has focused on thromboprophylaxis, with warfarin as the mainstay of therapy. However, concerns over ease of use and safety have limited its use. Three novel oral anticoagulants have been approved for use in stroke prevention in AF based on randomized data: 1) dabigatran, studied in Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY); 2) rivaroxaban, studied in Rivaroxaban Once-daily, Oral, Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF); and 3) apixaban, studied in Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE). In this review, we focus on apixaban and discuss subgroup analyses that have been performed in the three trials comparing novel oral anticoagulants with warfarin. We conclude with recommendations regarding further investigations.

Stop the clots, but at what cost? Pharmacoeconomics of dabigatran etexilate for the prevention of stroke in subjects with atrial fibrillation: a systematic literature review

Dabigatran etexilate is a newly approved agent for prophylaxis of stroke in atrial fibrillation. Through narrative review, the authors assess evidence of the efficacy of dabigatran in stroke prevention, focusing on the multicenter, randomized trial RE-LY. The authors complement this with a review of the clinical efficacy of standard treatments (antiplatelet and warfarin). Finally, the authors present a systematic review of published studies describing the economics of dabigatran. Our systematic search gave six economic reviews from a variety of healthcare systems (the USA, Canada and the UK) and utilizing different economic models. Analyses suggest economic benefit of high- or sequential-dose dabigatran, particularly when stroke risk is high; intracerebral hemorrhage risk is high or warfarin control is poor. However, questions remain around dabigatran tolerability, compliance and possible unexpected adverse events.

Cost-effectiveness of new oral anticoagulants in the prevention of stroke in patients with atrial fibrillation

Atrial fibrillation (AF) is a common arrhythmia and the leading cause of stroke, an event with high human and economic burden. Novel oral anticoagulants have been approved in many markets as alternatives to warfarin for stroke prevention in patients with AF - dabigatran etexilate, apixaban and rivaroxaban. Given the high burden of AF, and given that new treatments can more effectively prevent stroke than warfarin, but at higher drug cost, there has been a need for systematic evaluation of the costs and benefits of these new treatments. In this study, we summarize the findings of a systematic literature review on the cost-effectiveness of the new oral anticoagulants. We find that there is substantial heterogeneity between the studies and their numerical findings, despite using a common set of four trials for their clinical inputs. However, there is broad consensus among them that each of the novel oral anticoagulants is cost-effective versus warfarin or aspirin.

A comparative analysis of models used to evaluate the cost-effectiveness of dabigatran versus warfarin for the prevention of stroke in atrial fibrillation

BACKGROUND

A number of models exploring the cost-effectiveness of dabigatran versus warfarin for stroke prevention in atrial fibrillation have been published. These studies found dabigatran was generally cost-effective, considering well-accepted willingness-to-pay thresholds, but estimates of the incremental cost-effectiveness ratios (ICERs) varied, even in the same setting. The objective of this study was to compare the findings of the published economic models and identify key model features accounting for differences.

METHODS

All aspects of the economic evaluations were reviewed: model approach, inputs, and assumptions. A previously published model served as the reference model for comparisons of the selected studies in the US and UK settings. The reference model was adapted, wherever possible, using the inputs and key assumptions from each of the other published studies to determine if results could be reproduced in the reference model. Incremental total costs, incremental quality-adjusted life years (QALYs), and ICERs (cost per QALY) were compared between each study and the corresponding adapted reference model. The impact of each modified variable or assumption was tracked separately.

RESULTS

The selected studies were in the US setting (2), the Canadian setting (1), and the UK setting (2). All models used the Randomized Evaluation of Long-Term Anticoagulation study (RE-LY) as the main source for clinical inputs, and all used a Markov modelling approach, except one that used discrete event simulation. The reference model had been published in the Canadian and UK settings. In the UK setting, the reference model reported an ICER of UK£4,831, whereas the other UK-based analysis reported an ICER of UK£23,082. When the reference model was modified to use the same population characteristics, cost inputs, and utility inputs, it reproduced the results of the other model (ICER UK£25,518) reasonably well. Key reasons for the different results between the two models were the assumptions on the event utility decrement and costs associated with intracranial haemorrhage, as well as the costs of warfarin monitoring and disability following events. In the US setting, the reference model produced an ICER similar to the ICER from one of the US models (US$15,115/QALY versus US$12,386/QALY, respectively) when modelling assumptions and input values were transferred into the reference model. Key differences in results could be explained by the population characteristics (age and baseline stroke risk), utility assigned to events and specific treatments, adjustment of stroke and intracranial haemorrhage risk over time, and treatment discontinuation and switching. The reference model was able to replicate the QALY results, but not the cost results, reported by the other US cost-effectiveness analysis. The parameters driving the QALY results were utility values by disability levels as well as utilities assigned to specific treatments, and event and background mortality rates.

CONCLUSIONS

Despite differences in model designs and structures, it was mostly possible to replicate the results published by different authors and identify variables responsible for differences between ICERs using a reference model approach. This enables a better interpretation of published findings by focusing attention on the assumptions underlying the key model features accounting for differences.

Is dabigatran considered a cost-effective alternative to warfarin treatment: a review of current economic evaluations worldwide

OBJECTIVE

Dabigatran was the first of a new generation of anticoagulation drugs for the indication of non-valvular atrial fibrillation (AF) to be approved. Evidence show that dabigatran 150 mg twice daily significantly reduces the risk of stroke and systemic embolism (RR = 0.65; p < 0.001) and shows a comparable rate of major bleedings (RR = 0.93; p = 0.32), whereas dabigatran 110 mg twice daily was associated with a comparable rate of stroke and systemic embolism (RR = 0.90; p = 0.30) and a significantly lower rate of major bleedings compared to warfarin treatment (RR = 0.80; p = 0.003). The purpose is to review current economic evaluations of these alternatives for healthcare professionals to include these findings in their decision-making.

METHODS

A systematic literature search identified 43 economic evaluations, of which 10 were included and evaluated according to the Consensus Health Economic Criteria list (CHEC-list) and the Oxford model.

RESULTS

Six economic evaluations concluded that dabigatran was a cost-effective alternative to warfarin. One evaluation concluded the same except when quality in warfarin treatment was excellent, with a mean time in therapeutic range (TTR) > 73%. Three evaluations concluded that dabigatran was a cost-effective alternative to warfarin in patient sub-groups; TTR ≤ 64%, congestive heart failure, hypertension, age ≥ 75, diabetes mellitus, prior stroke or transient ischemic attack (CHADS2 score) ≥3, or a CHADS2 score = 2 unless international normalized ratio (INR) control was excellent, and with high risk of stroke or in a low-quality warfarin treatment. Dabigatran 110 mg twice daily was in general dominated by dabigatran 150 mg twice daily.

LIMITATIONS

The evaluations were not fully homogeneous, as some did not include loss of productivity, costs of dyspepsia, and annual costs of dabigatran patient management.

CONCLUSIONS

In the majority of the economic evaluations, dabigatran is a cost-effective alternative to warfarin treatment. In some evaluations dabigatran is only cost-effective in sub-groups, such as patients with a low TTR-value in warfarin treatment and a CHADS2 score ≥2.