Decision analysis and guidelines for anticoagulant therapy to prevent stroke in patients with atrial fibrillation

Characterizing atrial fibrillation symptom improvement following de novo catheter ablation

AIMS

Atrial fibrillation (AF) symptom relief is a primary indication for catheter ablation, but AF symptom resolution is not well characterized. The study objective was to describe AF symptom documentation in electronic health records (EHRs) pre- and post-ablation and identify correlates of post-ablation symptoms.

METHODS AND RESULTS

We conducted a retrospective cohort study using EHRs of patients with AF (n = 1293), undergoing ablation in a large, urban health system from 2010 to 2020. We extracted symptom data from clinical notes using a natural language processing algorithm (F score: 0.81). We used Cochran's Q tests with post-hoc McNemar's tests to determine differences in symptom prevalence pre- and post-ablation. We used logistic regression models to estimate the adjusted odds of symptom resolution by personal or clinical characteristics at 6 and 12 months post-ablation. In fully adjusted models, at 12 months post-ablation patients, patients with heart failure had significantly lower odds of dyspnoea resolution [odds ratio (OR) 0.38, 95% confidence interval (CI) 0.25-0.57], oedema resolution (OR 0.37, 95% CI 0.25-0.56), and fatigue resolution (OR 0.54, 95% CI 0.34-0.85), but higher odds of palpitations resolution (OR 1.90, 95% CI 1.25-2.89) compared with those without heart failure. Age 65 and older, female sex, Black or African American race, smoking history, and antiarrhythmic use were also associated with lower odds of resolution of specific symptoms at 6 and 12 months.

CONCLUSION

The post-ablation symptom patterns are heterogeneous. Findings warrant confirmation with larger, more representative data sets, which may be informative for patients whose primary goal for undergoing an ablation is symptom relief.

Bleeding risk in patients prescribed dual antiplatelet therapy and triple therapy after coronary interventions: the ADAPTT retrospective population-based cohort studies

Background

Bleeding among populations undergoing percutaneous coronary intervention or coronary artery bypass grafting and among conservatively managed patients with acute coronary syndrome exposed to different dual antiplatelet therapy and triple therapy (i.e. dual antiplatelet therapy plus an anticoagulant) has not been previously quantified.

Objectives

The objectives were to estimate hazard ratios for bleeding for different antiplatelet and triple therapy regimens, estimate resources and the associated costs of treating bleeding events, and to extend existing economic models of the cost-effectiveness of dual antiplatelet therapy.

Design

The study was designed as three retrospective population-based cohort studies emulating target randomised controlled trials.

Setting

The study was set in primary and secondary care in England from 2010 to 2017.

Participants

Participants were patients aged ≥ 18 years undergoing coronary artery bypass grafting or emergency percutaneous coronary intervention (for acute coronary syndrome), or conservatively managed patients with acute coronary syndrome.

Data sources

Data were sourced from linked Clinical Practice Research Datalink and Hospital Episode Statistics.

Interventions

Coronary artery bypass grafting and conservatively managed acute coronary syndrome: aspirin (reference) compared with aspirin and clopidogrel. Percutaneous coronary intervention: aspirin and clopidogrel (reference) compared with aspirin and prasugrel (ST elevation myocardial infarction only) or aspirin and ticagrelor.

Main outcome measures

Primary outcome: any bleeding events up to 12 months after the index event. Secondary outcomes: major or minor bleeding, all-cause and cardiovascular mortality, mortality from bleeding, myocardial infarction, stroke, additional coronary intervention and major adverse cardiovascular events.

Results

The incidence of any bleeding was 5% among coronary artery bypass graft patients, 10% among conservatively managed acute coronary syndrome patients and 9% among emergency percutaneous coronary intervention patients, compared with 18% among patients prescribed triple therapy. Among coronary artery bypass grafting and conservatively managed acute coronary syndrome patients, dual antiplatelet therapy, compared with aspirin, increased the hazards of any bleeding (coronary artery bypass grafting: hazard ratio 1.43, 95% confidence interval 1.21 to 1.69; conservatively-managed acute coronary syndrome: hazard ratio 1.72, 95% confidence interval 1.15 to 2.57) and major adverse cardiovascular events (coronary artery bypass grafting: hazard ratio 2.06, 95% confidence interval 1.23 to 3.46; conservatively-managed acute coronary syndrome: hazard ratio 1.57, 95% confidence interval 1.38 to 1.78). Among emergency percutaneous coronary intervention patients, dual antiplatelet therapy with ticagrelor, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.47, 95% confidence interval 1.19 to 1.82), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.06, 95% confidence interval 0.89 to 1.27). Among ST elevation myocardial infarction percutaneous coronary intervention patients, dual antiplatelet therapy with prasugrel, compared with dual antiplatelet therapy with clopidogrel, increased the hazard of any bleeding (hazard ratio 1.48, 95% confidence interval 1.02 to 2.12), but did not reduce the incidence of major adverse cardiovascular events (hazard ratio 1.10, 95% confidence interval 0.80 to 1.51). Health-care costs in the first year did not differ between dual antiplatelet therapy with clopidogrel and aspirin monotherapy among either coronary artery bypass grafting patients (mean difference £94, 95% confidence interval -£155 to £763) or conservatively managed acute coronary syndrome patients (mean difference £610, 95% confidence interval -£626 to £1516), but among emergency percutaneous coronary intervention patients were higher for those receiving dual antiplatelet therapy with ticagrelor than for those receiving dual antiplatelet therapy with clopidogrel, although for only patients on concurrent proton pump inhibitors (mean difference £1145, 95% confidence interval £269 to £2195).

Conclusions

This study suggests that more potent dual antiplatelet therapy may increase the risk of bleeding without reducing the incidence of major adverse cardiovascular events. These results should be carefully considered by clinicians and decision-makers alongside randomised controlled trial evidence when making recommendations about dual antiplatelet therapy.

Limitations

The estimates for bleeding and major adverse cardiovascular events may be biased from unmeasured confounding and the exclusion of an eligible subgroup of patients who could not be assigned an intervention. Because of these limitations, a formal cost-effectiveness analysis could not be conducted.

Future work

Future work should explore the feasibility of using other UK data sets of routinely collected data, less susceptible to bias, to estimate the benefit and harm of antiplatelet interventions.

Trial registration

This trial is registered as ISRCTN76607611.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 8. See the NIHR Journals Library website for further project information.

Educational Needs of People Living with Atrial Fibrillation: A Qualitative Study

Background

This study explored the educational and self‐management needs of adults living with atrial fibrillation (AF).

Methods and Results

This is a qualitative study of adults living with AF, clinicians, and expert key stakeholders. Interviews were conducted via a one‐to‐one semistructured videoconference or phone and transcribed verbatim for thematic analysis. A total of 34 participants were recruited and included in analyses (clinicians n=13; experts n=13, patients n=8). Interviews were on average 40 (range 20–70) minutes in duration. Three key themes were identified: (1) “Patient‐centered AF education”; (2) “Prioritizing AF education”; and (3) “Timing AF education.” The availability of credible information was perceived as highly variable. Information primarily focused on anticoagulation, or procedural information, as opposed to other aspects of management, such as risk factor reduction. Factors to optimize learning, such as multimedia, apps, case studies, or the use of visuals were perceived as important. Continuity of care, including engagement of caregivers, was important to help develop relationships, and facilitate understanding, while concurrently creating opportunities for timely targeted education. Clinicians described acute care as a suboptimal setting to deliver education. Competing interests aligned with the time‐pressured context of acute care were prioritized over patient education. In contrast, patients valued continuity of care. AF education strategies need to pivot from a “one size fits all” approach and modernize to implement a range of approaches.

Conclusions

There remain many unmet needs in the provision of quality AF education to support self‐management. Multimodal offerings and the ability to tailor to individual patient needs are important design considerations for new education programs.

[GRADE guidelines 20: Assessing the certainty of evidence in the importance of outcomes or values and preferences-inconsistency, imprecision, and other domains]

OBJECTIVE

To provide Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) guidance for assessing inconsistency, imprecision, and other domains for the certainty of evidence about the relative importance of outcomes.

STUDY DESIGN AND SETTING

We applied the GRADE domains to rate the certainty of evidence in the importance of outcomes to several systematic reviews, iteratively reviewed draft guidance, and consulted GRADE members and other stakeholders for feedback.

RESULTS

We describe the rationale for considering the remaining GRADE domains when rating the certainty in a body of evidence for the relative importance of outcomes. As meta-analyses are not common in this context, inconsistency and imprecision assessments are challenging. Furthermore, confusion exists about inconsistency, imprecision, and true variability in the relative importance of outcomes. To clarify this issue, we suggest that the true variability is neither equivalent to inconsistency nor imprecision. Specifically, inconsistency arises from population, intervention, comparison and outcome and methodological elements that should be explored and, if possible, explained. The width of the confidence interval and sample size inform judgments about imprecision. We also provide suggestions on how to detect publication bias and discuss the domains to rate up the certainty.

CONCLUSION

We provide guidance and examples for rating inconsistency, imprecision, and other domains for a body of evidence describing the relative importance of outcomes.

Returning Cardiac Rhythm Data to Patients: Opportunities and Challenges

Spurred by federal legislation, professional organizations, and patients themselves, patient access to data from electronic cardiac devices is increasingly transparent. Patients can collect data through consumer devices and access data traditionally shared only with health care providers. These data may improve screening, self-management, and shared decision-making for cardiac arrhythmias, but challenges remain, including patient comprehension, communication with providers, and sustained engagement. Ways to address these challenges include leveraging visualizations that support comprehension, involving patients in designing and developing patient-facing digital tools, and establishing clear practices and goals for data exchange with health care providers.

Cost-Effectiveness Analysis of Transcatheter Arterial Embolization Techniques for the Treatment of Gastrointestinal Bleeding in the United States

OBJECTIVES

Gastrointestinal (GI) bleeding is a common medical emergency associated with significant mortality. Transcatheter arterial embolization first was introduced by Rosch et al as an alternative to surgery for upper GI bleeding. The clinical success in patients with GI bleeding treated with transcatheter arterial embolization previously has been reported. However, there are no cost-effectiveness analyses reported to date. Here we report cost-effectiveness analysis of N-butyl 2-cyanoacrylate glue (NBCA) and ethylene-vinyl alcohol copolymer (Onyx) versus coil (gold standard) for treatment of GI bleeding from a healthcare payer perspective.

METHODS

Fixed-effects modeling with a generalized linear mixed method was used in NBCA and coil intervention arms to determine the pooled probabilities of clinical success and mortality with complications with their confidence intervals, while the Clopper-Pearson model was used for Onyx to determine the same parameters. Models were provided by the "Meta-Analysis with R" software package. A decision tree was built for cost-effectiveness analysis, and Microsoft Excel was used for probabilistic sensitivity analysis. The cost-effective option was determined based on the incremental cost-effectiveness ratio and scatter plots of incremental cost versus incremental quality-adjusted life-years.

RESULTS

Comparing scatter plots and incremental cost-effectiveness ratio results, -$1024 and -$1349 per quality-adjusted life-year for Onyx and N-butyl 2-cyanoacrylate glue, respectively, Onyx was the least expensive and most effective intervention.

CONCLUSION

Onyx was the dominant strategy regardless of threshold values. Our analyses provide a framework for researchers to predict the target clinical effectiveness for early-stage TAE interventions and guide resource allocation decisions.

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.

A cost-effectiveness analysis model of Preventicus atrial fibrillation screening from the point of view of statutory health insurance in Germany

BACKGROUND

With atrial fibrillation (AF) the risk of stroke is 4.2-fold increased to a comparable population without AF. This risk decreases by up to 70% if AF is detected early enough and effective stroke preventive measures are taken as recommended by international guidelines. Long-term studies found large number of subjects with undiagnosed AF. Preventicus Heartbeats" is a hands-on screening tool for use on smartphone to diagnose AF with high sensitivity and specificity. The aim of this study is to research the cost-effectiveness of systematic screening for AF with this smartphone application.

METHOD

Employing a Markov model we analysed the cost-effectiveness of the "Preventicus Heartbeats" screening for Germany, i.e. from the perspective of German statutory sick funds.

RESULTS

For a cohort of 10,000 insured 75-year-old the use of the diagnostic app could avoid 60 strokes in the remaining lifetime thereof 32 strokes in the next four years. Former models have applied similar cohorts. The same cohort showed an increase in quality-adjusted life years (QALY) in the remaining lifetime of 165 QALYs in the scenario with screening versus. without screening and a decrease in discounted lifetime costs (including risk compensation effects) of €129 per participant (€148 for male, €114 for female participants).

CONCLUSIONS

The modelling demonstrates the health benefits and economic effects of an implementation of a systematic screening on AF with "Preventicus Heartbeats", given the perspective of the German payer, the statutory health care system.

How the Results of a Randomized Trial of Catheter-Directed Thrombolysis Versus Anticoagulation alone for Submassive Pulmonary Embolism Would Affect Patient and Physician Decision Making: Report of an Online Survey

The purpose is to investigate how the outcomes of a randomized controlled trial (RCT) of catheter-directed thrombolysis (CDT) versus anticoagulation alone for acute submassive PE would affect clinical decision-making. An online survey was sent to the Pulmonary Embolism Response Team Consortium members and the North American Thrombosis Forum members. Participants rated their preference for CDT on a 5-point scale in 5 RCT outcome scenarios. In all scenarios, subjects in the CDT group walked farther at 1-year than those in the anticoagulation group. A total of 83.3% of patients and 67.1% of physicians preferred CDT (score > 3) if it improved exercise capacity and did not increase bleeding. In every scenario, patients scored CDT higher than physicians (p < 0.05 for each). Bleeding and clinical deterioration were independently associated with the mean score. Patients’ age, gender, and history of PE did not influence CDT scores (p = 0.083, p = 0.071, p = 0.257 respectively). For patients, 60% > 60 years, 65.5% < 60 years, 57.1% of men, and 66.3% of women preferred CDT across scenarios. In conclusion, the majority of respondents would choose CDT if it improves long-term exercise capacity and does not increase bleeding. Patients appear to accept a higher bleeding risk than physicians if CDT improves long-term exercise capacity.

Cost-Effectiveness of Aspirin Adherence for Secondary Prevention of Cardiovascular Events

BACKGROUND

Suboptimal adherence to aspirin therapy for secondary prevention of cardiovascular (CV) events is an important public health problem. Prior studies have demonstrated non-adherent patients are at higher risk of experiencing CV events.

OBJECTIVES

This study aimed to estimate the clinical and economic outcomes of aspirin non-adherence in patients with a prior primary CV event.

METHODS

We developed a Markov model to estimate the cost-effectiveness of aspirin adherence from a generic US managed care payer perspective over a 5-year time horizon. Costs, utilities and rates of aspirin adherence, CV events and adverse events were gathered from published literature to populate the model. Outcomes were quality-adjusted life years (QALYs), costs (US$) and incremental cost-effectiveness ratios (ICERs). We applied the model separately to a population without type II diabetes as a comorbidity (non-diabetic model) and a population with type II diabetes (type II diabetes model). A one-way sensitivity analysis was performed to assess the model uncertainty.

RESULTS

The base case showed adherent patients lived 0.25 and 0.36 QALYs longer than non-adherent patients in the non-diabetic model and type II diabetes model, respectively. Adherence to aspirin had an ICER of US$25/QALY in the non-diabetic population, while it saved US$297 per patient over a 5-year period in the type II diabetes population. One-way sensitivity analysis showed the models were most sensitive to rates of non-fatal events in non-adherent patients.

CONCLUSION

This study suggests aspirin adherence may improve QALYs for patients with a prior primary CV event. Further, it may decrease costs in patients with type II diabetes. While additional research is needed to validate these results, payers may wish to increase strategies to promote adherence in order to improve population health.

TRIAL REGISTRATION

Not applicable.

Health-related quality of life impact of minor and major bleeding events during dual antiplatelet therapy: a systematic literature review and patient preference elicitation study

Background

Dual antiplatelet therapy (DAPT) is the recommended preventative treatment for secondary ischaemic events, but increases the risk of bleeding, potentially affecting patients’ health-related quality-of-life (HRQoL). Varied utility decrements have been used in cost-effectiveness models assessing alternative DAPT regimens, but it is unclear which of these decrements are most appropriate. Therefore, we reviewed existing sources of utility decrements for bleeds in patients receiving DAPT and undertook primary research to estimate utility decrements through a patient elicitation exercise using vignettes and the EuroQol EQ-5D.

Methods

MEDLINE, PubMed and references of included studies were searched. Primary research and decision analytic modelling studies reporting utility decrements for bleeds related to DAPT were considered. For the primary research study, 21 participants completed an elicitation exercise involving vignettes describing minor and major bleeds and the EQ-5D-3 L and EQ-5D-5 L. Utility decrements were derived using linear regression and compared to existing estimates.

Results

Four hundred forty-two citations were screened, of which 12 studies were included for review. Reported utility decrements ranged from − 0.002 to − 0.03 for minor bleeds and − 0.007 to − 0.05 for major bleeds. Data sources used to estimate the decrements, however, lacked relevance to our population group and few studies adequately reported details of their measurement and valuation approaches. No study completely adhered to reimbursement agency requirements in the UK according to the National Institute for Health and Care Excellence reference case. Our primary research elicited utility decrements overlapped existing estimates, ranging from − 0.000848 to − 0.00828 for minor bleeds and − 0.0187 to − 0.0621 for major bleeds. However, the magnitude of difference depended on the instrument, estimation method and valuation approach applied.

Conclusions

Several sources of utility decrements for bleeds are available for use in cost-effectiveness analyses, but are of limited quality and relevance. Our elicitation exercise has derived utility decrements from a relevant patient population, based on standardised definitions of minor and major bleeding events, using a validated HRQoL instrument and have been valued using general population tariffs. We suggest that our utility decrements be used in future cost-effectiveness analyses of DAPT.

Electronic supplementary material

The online version of this article (10.1186/s12955-018-1019-3) contains supplementary material, which is available to authorized users.

Would the Use of Edoxaban Be Cost-effective for the Prevention of Stroke and Systemic Embolism in Patients With Nonvalvular Atrial Fibrillation in Spain?

INTRODUCTION AND OBJECTIVES

To assess the cost-effectiveness of edoxaban vs acenocoumarol in the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation (NVAF) in Spain.

METHODS

Markov model, adapted to the Spanish setting from the perspective of the National Health System, stimulating the progression of a hypothetical cohort of patients with NVAF throughout their lifetime, with different health states: stroke, haemorrhage, and other cardiovascular complications. Efficacy and safety data were obtained from the available clinical evidence (mainly from the phase III ENGAGE AF-TIMI 48 study). The costs of managing NVAF and its complications were obtained from Spanish sources.

RESULTS

Edoxaban use led to 0.34 additional quality-adjusted life years (QALY) compared with acenocoumarol. The incremental cost with edoxaban was 3916€, mainly because of higher pharmacological costs, which were partially offset by lower costs of treatment monitoring and managing NVAF events and complications. The cost per QALY was 11 518€, within the thresholds commonly considered cost-effective in Spain (25 000-30 000 €/QALY). The robustness of the results was confirmed by various sensitivity analyses.

CONCLUSIONS

Edoxaban is a cost-effective alternative to acenocoumarol in the prevention of stroke and systemic embolism in patients with NVAF in Spain.

Shared decision-making tool for thromboprophylaxis in atrial fibrillation - A feasibility study

BACKGROUND

Appropriate thromboprophylaxis for patients with atrial fibrillation or atrial flutter (AF) remains a national challenge.

METHODS

We hypothesized that a shared decision-making interaction facilitated by an Atrial Fibrillation Shared Decision Making Tool (AFSDM) would improve patient knowledge about atrial fibrillation, and the risks and benefits of various treatment options for stroke prevention; increase satisfaction with the decision-making process; improve the therapeutic alliance between patient and the clinical care team; and increase medication adherence. Using a pre- and post-visit study design, we enrolled 76 patients and completed 2 office visits and 1-month telephone follow-up for 65 patients being seen in our Arrhythmia Clinic over the 1-year period (July 2016 through June 2017). Our primary outcome measure was change in decisional conflict between the first and second clinical visit.

RESULTS

Decisional conflict decreased from an average of 31 to 9. Mean change was 22.3 (95% CI, 25.7 - 37.1), corresponding to an effect size of 0.94 standard deviations. Satisfaction with decision increased from 4.0 to 4.5, measures of therapeutic alliance with the care team (Kim Alliance scale) increased from 100.1 to 103.1, and satisfaction with provider increased from 4.2 to 4.5 (P < .0001 for all measures). AF knowledge assessment scores increased from 8.4 to 9.1, and knowledge about personal stroke and bleeding risk increased from 1 to 1.5 (P < .0001). Finally, medication adherence improved as reflected by an increase in the Morisky Medication Adherence scale from 5.9 to 6.4 (P < .0001).

CONCLUSIONS

A shared decision-making interaction, facilitated by an AFSDM can significantly improve multiple measures of decision-making quality, leading to improved medication adherence and patient satisfaction.

Bleeding risk assessment and management in atrial fibrillation patients

In this executive summary of a Consensus Document from the European Heart Rhythm Association, endorsed by the European Society of Cardiology Working Group on Thrombosis, we comprehensively review the published evidence and propose a consensus on bleeding risk assessments in atrial fibrillation (AF) patients. The main aim of the document was to summarise ‘best practice’ in dealing with bleeding risk in AF patients when approaching antithrombotic therapy, by addressing the epidemiology and size of the problem, and review established bleeding risk factors. We also summarise definitions of bleeding in the published literature. Patient values and preferences balancing the risk of bleeding against thromboembolism as well as the prognostic implications of bleeding are reviewed. We also provide an overview of published bleeding risk stratification and bleeding risk schema. Brief discussion of special situations (e.g. periablation, peri-devices such as implantable cardioverter defibrillators [ICD] or pacemakers, presentation with acute coronary syndromes and/or requiring percutanous coronary interventions/stents and bridging therapy) is made, as well as a discussion of the prevention of bleeds and managing bleeding complications. Finally, this document puts forwards consensus statements that may help to define evidence gaps and assist in everyday clinical practice.

Patient values and preferences for antithrombotic therapy in atrial fibrillation

Guidelines recommend that patients’ values and preferences should be considered when selecting stroke prevention therapy for atrial fibrillation (SPAF). However, doing so is difficult, and tools to assist clinicians are sparse. We performed a narrative systematic review to provide clinicians with insights into the values and preferences of AF patients for SPAF antithrombotic therapy. Narrative systematic review of published literature from database inception. Research questions: 1) What are patients’ AF and SPAF therapy values and preferences? 2) How are SPAF therapy values and preferences affected by patient factors? 3) How does conveying risk information affect SPAF therapy preferences? and 4) What is known about patient values and preferences regarding novel oral anticoagulants (NOACs) for SPAF? Twenty-five studies were included. Overall study quality was moderate. Severe stroke was associated with the greatest disutility among AF outcomes and most patients value the stroke prevention efficacy of therapy more than other attributes. Utilities, values, and preferences about other outcomes and attributes of therapy are heterogeneous and unpredictable. Patients’ therapy preferences usually align with their values when individualised risk information is presented, although divergence from this is common. Patients value the attributes of NOACs but frequently do not prefer NOACs over warfarin when all therapy-related attributes are considered. In conclusion, patients’ values and preferences for SPAF antithrombotic therapy are heterogeneous and there is no substitute for directly clarifying patients’ individual values and preferences. Research using choice modelling and tools to help clinicians and patients clarify their SPAF therapy values and preferences are needed.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Cost-Effectiveness of Percutaneous Closure of the Left Atrial Appendage in Atrial Fibrillation Based on Results From PROTECT AF Versus PREVAIL

BACKGROUND

Randomized trials of left atrial appendage (LAA) closure with the Watchman device have shown varying results, and its cost effectiveness compared with anticoagulation has not been evaluated using all available contemporary trial data.

METHODS AND RESULTS

We used a Markov decision model to estimate lifetime quality-adjusted survival, costs, and cost effectiveness of LAA closure with Watchman, compared directly with warfarin and indirectly with dabigatran, using data from the long-term (mean 3.8 year) follow-up of Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation (PROTECT AF) and Prospective Randomized Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation (PREVAIL) randomized trials. Using data from PROTECT AF, the incremental cost-effectiveness ratios compared with warfarin and dabigatran were $20 486 and $23 422 per quality-adjusted life year, respectively. Using data from PREVAIL, LAA closure was dominated by warfarin and dabigatran, meaning that it was less effective (8.44, 8.54, and 8.59 quality-adjusted life years, respectively) and more costly. At a willingness-to-pay threshold of $50 000 per quality-adjusted life year, LAA closure was cost effective 90% and 9% of the time under PROTECT AF and PREVAIL assumptions, respectively. These results were sensitive to the rates of ischemic stroke and intracranial hemorrhage for LAA closure and medical anticoagulation.

CONCLUSIONS

Using data from the PROTECT AF trial, LAA closure with the Watchman device was cost effective; using PREVAIL trial data, Watchman was more costly and less effective than warfarin and dabigatran. PROTECT AF enrolled more patients and has substantially longer follow-up time, allowing greater statistical certainty with the cost-effectiveness results. However, longer-term trial results and postmarketing surveillance of major adverse events will be vital to determining the value of the Watchman in clinical practice.

An Evidence-Based Medicine Approach to Antihyperglycemic Therapy in Diabetes Mellitus to Overcome Overtreatment

Overtreatment is pervasive in medicine and leads to potential patient harms and excessive costs in health care. Although evidence-based medicine is often derided as practice by rote algorithmic medicine, the appropriate application of key evidence-based medicine principles in clinical decision making is fundamental to preventing overtreatment and promoting high-value, individualized patient-centered care. Specifically, this article discusses the importance of (1) using absolute rather than relative estimates of benefits to inform treatment decisions; (2) considering the time horizon to benefit of treatments; (3) balancing potential harms and benefits; and (4) using shared decision making by physicians to incorporate the patient's values and preferences into treatment decisions. Here, we illustrate the application of these principles to considering the decision of whether or not to recommend intensive glycemic control to patients to minimize microvascular and cardiovascular complications in type 2 diabetes mellitus. Through this lens, this example will illustrate how an evidence-based medicine approach can be used to individualize glycemic goals and prevent overtreatment, and can serve as a template for applying evidence-based medicine to inform treatment decisions for other conditions to optimize health and individualize patient care.

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.

Lasting effect of an oral hygiene care program for patients with stroke during in-hospital rehabilitation: a randomized single-center clinical trial

PURPOSE

Because the oral hygiene is poorly prioritized in the immediate post-stroke period, we implemented an oral hygiene care program (OHCP) for stroke in-patients and evaluated its persistence after discharge.

METHOD

In all, 62 patients with stroke who were admitted to the rehabilitation ward were randomly assigned to two groups: 33 patients to the intervention group and 29 to the control group. The OHCP, including tooth brushing education and professional tooth cleaning, was administered to the intervention group twice a week six times during in-hospital rehabilitation. Oral health status was examined both at baseline and three months after discharge from the hospital. Oral hygiene status was examined at three- to four-day intervals five times during the hospitalization period.

RESULTS

After OHCP, oral hygiene status including the plaque index, calculus index, and O'Leary plaque index improved significantly in the intervention group, compared to the control group (p < 0.05). In the intervention group, after administration of the OHCP for the fourth time, the O'Leary index improved significantly, and remained high when checked three months after discharge (p < 0.001).

CONCLUSIONS

An OHCP conducted during in-hospital rehabilitation was effective in improving oral health and plaque control performance among patients with stroke, with effects still seen three months after discharge from the hospital. Implications for Rehabilitation Initial oral hygiene status and plaque control performance were poor in stroke patients who were in rehabilitation center. An oral hygiene care program during in-hospital rehabilitation was effective in improving oral hygiene status and plaque control performance among stroke patients at three months after discharge. Repeated tooth brushing education and professional tooth cleaning were necessary to improve plaque control performance of stroke patients.

Preference-Based Antithrombotic Therapy in Atrial Fibrillation: Implications for Clinical Decision Making

Background. Patient preferences and expert-generated clinical practice guidelines regarding treatment decisions may not be identical. The authors compared the thresholds for antithrombotic treatment from studies that determined or modeled the treatment preferences of patients with atrial fibrillation with recommendations from clinical practice guidelines. Methods. Methods included MEDLINE identification, systematic review, and pooling with some reanalysis of primary data from relevant studies. Results. Eight pertinent studies, including 890 patients, were identified. These studies used 3 methods (decision analysis, probability tradeoff, and decision aids) to determine or model patient preferences. All methods highlighted that the threshold above which warfarin was preferred over aspirin was highly variable. In 6 of 8 studies, patient preferences indicated that fewer patients would take warfarin compared to the recommendations of the guidelines. In general, at a stroke rate of 1% with aspirin, half of the participants would prefer warfarin, and at a rate of 2% with aspirin, two thirds would prefer warfarin. In 3 studies, warfarin must provide at least a 0.9% to 3.0% per year absolute reduction in stroke risk for patients to be willing to take it, corresponding to a stroke rate of 2% to 6% on aspirin. Conclusions. For patients with atrial fibrillation, treatment recommendations from clinical practice guidelines often differ from patient preferences, with substantial heterogeneity in their individual preferences. Since patient preferences can have a substantial impact on the clinical decision-making process, acknowledgment of their importance should be incorporated into clinical practice guidelines. Practicing physicians need to balance the patient preferences with the treatment recommendations from clinical practice guidelines.

Cost-effectiveness analysis of left atrial appendage occlusion compared with pharmacological strategies for stroke prevention in atrial fibrillation

BACKGROUND

Transcatheter left atrial appendage occlusion (LAAO) is a promising therapy for stroke prophylaxis in non-valvular atrial fibrillation (NVAF) but its cost-effectiveness remains understudied. This study evaluated the cost-effectiveness of LAAO for stroke prophylaxis in NVAF.

METHODS

A Markov decision analytic model was used to compare the cost-effectiveness of LAAO with 7 pharmacological strategies: aspirin alone, clopidogrel plus aspirin, warfarin, dabigatran 110 mg, dabigatran 150 mg, apixaban, and rivaroxaban. Outcome measures included quality-adjusted life years (QALYs), lifetime costs and incremental cost-effectiveness ratios (ICERs). Base-case data were derived from ACTIVE, RE-LY, ARISTOTLE, ROCKET-AF, PROTECT-AF and PREVAIL trials. One-way sensitivity analysis varied by CHADS2 score, HAS-BLED score, time horizons, and LAAO costs; and probabilistic sensitivity analysis using 10,000 Monte Carlo simulations was conducted to assess parameter uncertainty.

RESULTS

LAAO was considered cost-effective compared with aspirin, clopidogrel plus aspirin, and warfarin, with ICER of US$5,115, $2,447, and $6,298 per QALY gained, respectively. LAAO was dominant (i.e. less costly but more effective) compared to other strategies. Sensitivity analysis demonstrated favorable ICERs of LAAO against other strategies in varied CHADS2 score, HAS-BLED score, time horizons (5 to 15 years) and LAAO costs. LAAO was cost-effective in 86.24 % of 10,000 simulations using a threshold of US$50,000/QALY.

CONCLUSIONS

Transcatheter LAAO is cost-effective for prevention of stroke in NVAF compared with 7 pharmacological strategies. The transcatheter left atrial appendage occlusion (LAAO) is considered cost-effective against the standard 7 oral pharmacological strategies including acetylsalicylic acid (ASA) alone, clopidogrel plus ASA, warfarin, dabigatran 110 mg, dabigatran 150 mg, apixaban, and rivaroxaban for stroke prophylaxis in non-valvular atrial fibrillation management.

European Society of Cardiology Guideline-Adherent Antithrombotic Treatment and Risk of Mortality in Asian Patients with Atrial Fibrillation

This study compared the risk of mortality in atrial fibrillation (AF) patients treated adherent to the 2012 European Society of Cardiology (ESC) guidelines for stroke prevention and those who were not treated according to guideline recommendations. This study used the Taiwan National Health Insurance Research Database. From 1996 to 2011, 354,649 newly diagnosed AF patients were identified as the study population. Among the study cohort, 45,595 and 309,054 patients were defined as Guideline-Adherent and Non-Adherent groups, respectively. During the follow up of 1,480,280 person-years, 133,552 (37.7%) patients experienced mortality. The risk of mortality was lower among AF patients whose treatment was adherent to the guideline recommendation for stroke prevention than those whose treatment was not (annual risk of mortality = 4.3% versus 10.0%) with an adjusted hazard ratio of 0.62 (95% confidence interval = 0.61–0.64, p value < 0.001) after adjusting for age, gender, CHA₂DS₂-VASc score and antiplatelet therapy. The findings were consistently observed after propensity matching analysis. In conclusion, the risk of mortality was lower for AF patients who were treated according to the antithrombotic recommendations of the 2012 ESC guidelines, guided by the CHA₂DS₂-VASc score. Better efforts to implement guidelines would lead to improved outcomes for patients with AF.

Clinical and Economic Implications of AF Related Stroke

A major cause of morbidity and mortality among patients with atrial fibrillation (AF) relates to the increased risk of stroke. The burden of illness that AF imparts on stroke is likely to increase with our aging populations and increasingly sophisticated cardiac monitoring techniques. Understanding the clinical and economic differences between AF related ischaemic stroke and non-AF related stroke is important if we are to improve future cost effectiveness analyses of potential preventative treatments, but also to help educate clinical and policy decision makers on use or availability of treatments to prevent AF related stroke. In this article we review the existing evidence that highlights differences in the clinical characteristics and outcomes between AF and non-AF stroke, as well as differences in their economic impact and discuss ways to improve future economic analyses.

Whose preferences should be elicited for use in health-care decision-making? A case study using anticoagulant therapy

The question of whose preferences to elicit in health-state valuation has been widely discussed in the literature. The importance of this debate lies in the fact that health-state utility values are used in health technology assessment (HTA); therefore, an individual's preferences can influence decision-making. If preferences differ across groups, making decisions based on one group's preferences may be suboptimal for the other. Preferences for benefits, risks, experiences and health states associated with anticoagulant therapies have been elicited by researchers due to the underutilization of warfarin and the introduction of non-vitamin K antagonist oral anticoagulants. The majority of existing studies elicit preferences from patient populations as opposed to other stakeholders such as the general public. This paper extends the preference debate by using this clinical area as a case study, with a particular focus on HTA guidelines and the recent advocacy of the use of preference information in benefit-risk assessments.

Universal versus genotype-guided use of direct oral anticoagulants in atrial fibrillation patients: a decision analysis

AIM

This study aims to compare clinical and economic outcomes of CYP2C9 and VKORC1 genotype-guided (PG-DOAC) versus universal use of direct oral anticoagulant (DOAC) for stroke prevention in patients with atrial fibrillation (AF).

METHODS

Outcomes of oral anticoagulation therapy were simulated using life-long Markov modeling. In PG-DOAC, patients with genotype of high or low warfarin sensitivity were treated with DOAC, and patients with normal warfarin sensitivity genotype received warfarin.

RESULTS

Expected quality-adjusted life-years (QALYs) and cost of DOAC were higher than PG-DOAC. Incremental cost per QALY (ICER) of DOAC versus PG-DOAC was 314,129 USD/QALY, exceeding willingness-to-pay threshold (50,000 USD/QALY).

CONCLUSION

Using individual genotype to guide the use of DOAC versus warfarin appears to be the preferred strategy.

A Decision Analysis of Percutaneous Left Atrial Appendage Occlusion Relative to Novel and Traditional Oral Anticoagulation for Stroke Prevention in Patients with New-Onset Atrial Fibrillation

Background. Percutaneous left atrial appendage occlusion (LAAO) is a nonpharmacologic approach for stroke prevention in nonvalvular atrial fibrillation (NVAF). No direct comparisons to novel oral anticoagulants (OACs) exists, limiting decision making on the optimal strategy for stroke prevention in NVAF patients. Addressing this gap in knowledge is timely given the recent debate by the US Food and Drug Administration regarding the effectiveness of LAAO. Objective. To assess the cost-effectiveness of LAAO and novel OACs relative to warfarin in patients with new-onset NVAF without contraindications to OAC. Design. A cost-utility analysis using a patient-level Markov micro-simulation decision analytic model was undertaken to determine the lifetime costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER) of LAAO and all novel OACs relative to warfarin. Effectiveness and utility data were obtained from the published literature and cost from the Ontario Drug Benefits Formulary and Case Costing Initiative. Results. Warfarin had the lowest discounted QALY (5.13 QALYs), followed by dabigatran (5.18 QALYs), rivaroxaban and LAAO (5.21 QALYs), and apixaban (5.25 QALYs). The average discounted lifetime costs were $15 776 for warfarin, $18 280 for rivaroxaban, $19 156 for apixaban, $20 794 for dabigatran, and $21 789 for LAAO. Apixaban dominated dabigatran and LAAO and demonstrated extended dominance over rivaroxaban. The ICER for apixaban relative to warfarin was $28 167/QALY. Apixaban was preferred in 40.2% of simulations at a willingness-to-pay threshold of $50 000/QALY. Limitations. Assumptions regarding clinical and methodological differences between published studies of each therapy were minimized. Conclusions. Apixaban is the most cost-effective therapy for stroke prevention in patients with new-onset NVAF without contraindications to OAC. Uncertainty around this conclusion exists, highlighting the need for further research.

Developing an Atrial Fibrillation Guideline Support Tool (AFGuST) for shared decision making

OBJECTIVE

Patient values and preferences are an important component to decision making when tradeoffs exist that impact quality of life, such as tradeoffs between stroke prevention and hemorrhage in patients with atrial fibrillation (AF) contemplating anticoagulant therapy. Our objective is to describe the development of an Atrial Fibrillation Guideline Support Tool (AFGuST) to assist the process of integrating patients' preferences into this decision.

MATERIALS AND METHODS

CHA2DS2VASc and HAS-BLED were used to calculate risks for stroke and hemorrhage. We developed a Markov decision analytic model as a computational engine to integrate patient-specific risk for stroke and hemorrhage and individual patient values for relevant outcomes in decisions about anticoagulant therapy.

RESULTS

Individual patient preferences for health-related outcomes may have greater or lesser impact on the choice of optimal antithrombotic therapy, depending upon the balance of patient-specific risks for ischemic stroke and major bleeding. These factors have been incorporated into patient-tailored booklets which, along with an informational video, were developed through an iterative process with clinicians and patient focus groups.

KEY LIMITATIONS

Current risk prediction models for hemorrhage, such as the HAS-BLED, used in the AFGuST, do not incorporate all potentially significant risk factors. Novel oral anticoagulant agents recently approved for use in the United States, Canada, and Europe have not been included in the AFGuST. Rather, warfarin has been used as a conservative proxy for all oral anticoagulant therapy.

CONCLUSIONS

We present a proof of concept that a patient-tailored decision-support tool could bridge the gap between guidelines and practice by incorporating individual patient's stroke and bleeding risks and their values for major bleeding events and stroke to facilitate a shared decision making process. If effective, the AFGuST could be used as an adjunct to published guidelines to enhance patient-centered conversations about the anticoagulation management.

Cost-effectiveness of anticoagulation in patients with nonvalvular atrial fibrillation with edoxaban compared to warfarin in Germany

We compared the cost-utility analysis for edoxaban at both doses with that of dabigatran at both doses, rivaroxaban, and apixaban (non vitamin K antagonist oral anticoagulants, NOAC) in a German population. Data of clinical outcome events were taken from edoxaban's ENGAGE-AF, dabigatran's RE-LY, rivaroxaban's ROCKET, and apixaban's ARISTOTLE trials. The base-case analyses of a 65-year-old person with a CHADS2 score >1 gained 0.17 and 0.21 quality-adjusted life years over warfarin for 30 mg od and 60 mg od edoxaban, respectively. The incremental cost-effectiveness ratio was 50.000 and 68.000 euro per quality-adjusted life years for the higher and lower dose of edoxaban (Monte Carlo simulation). These findings were also similar to those for apixaban and more cost-effective than the other NOAC regimens. The current market costs for direct oral anticoagulants are high in relation to the quality of life gained from a German public health care insurance perspective. The willingness-to-pay threshold was lowest for 60 mg edoxaban compared to all direct oral anticoagulants and for 30 mg edoxaban compared to dabigatran and rivaroxaban.

Cost effectiveness of rivaroxaban for stroke prevention in German patients with atrial fibrillation

OBJECTIVE

The aim of this study was to assess the cost effectiveness of the novel fixed-dose anticoagulant rivaroxaban compared with the current standard of care, warfarin, for the prevention of stroke in patients with atrial fibrillation (AF).

METHODS

A Markov model was constructed to model the costs and health outcomes of both treatments, potential adverse events, and resulting health states over 35 years. Analyses were based on a hypothetical cohort of 65-year-old patients with non-valvular AF at moderate to high risk of stroke. The main outcome measure was cost per quality-adjusted life-year (QALY) gained over the lifetime, and was assessed from the German Statutory Health Insurance (SHI) perspective. Costs and utility data were drawn from public data and the literature, while event probabilities were derived from both the literature and rivaroxaban's pivotal ROCKET AF trial.

RESULTS

Stroke prophylaxis with rivaroxaban offers health improvements over warfarin treatment at additional cost. From the SHI perspective, at baseline the incremental cost-effectiveness ratio of rivaroxaban was <euro>15,207 per QALY gained in 2014. The results were robust to changes in the majority of variables; however, they were sensitive to the price of rivaroxaban, the hazard ratios for stroke and intracranial hemorrhage, the time horizon, and the discount rate.

CONCLUSIONS

Our results showed that the substantially higher medication costs of rivaroxaban were offset by mitigating the shortcomings of warfarin, most notably frequent dose regulation and bleeding risk. Future health economic studies on novel oral anticoagulants should evaluate the cost effectiveness for secondary stroke prevention and, as clinical data from direct head-to-head comparisons become available, new anticoagulation therapies should be compared against each other.

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).

Patient values and preferences when choosing anticoagulants

BACKGROUND

New oral anticoagulants have similar efficacy and lower bleeding rates compared with warfarin. However, in case of bleeding there is no specific antidote to reverse their effects. We evaluated the preferences and values of anticoagulants of patients at risk of atrial fibrillation and those who have already made a decision regarding anticoagulation.

METHODS

We conducted a cross-sectional study of Veterans in the primary care clinics and the international normalized ratio (INR) laboratory. We developed an instrument with patient and physician input to measure patient values and preferences. The survey contained a hypothetical scenario of the risk of atrial fibrillation and the attributes of each anticoagulant. After the scenario, we asked participants to choose the option that best fits their preferences. The options were: 1) has better efficacy at reducing risk of stroke; 2) has been in the market for a long period of time; 3) has an antidote to reverse the rare case of bleeding; 4) has better quality of life profile with no required frequent laboratory tests; or 5) I want to follow physician recommendations. We stratified our results by those patients who are currently exposed to anticoagulants and those who are not exposed but are at risk of atrial fibrillation.

RESULTS

We approached 173 Veterans and completed 137 surveys (79% response rate). Ninety subjects were not exposed to anticoagulants, 46 reported being on warfarin, and one reported being on dabigatran at the time of the survey. Ninety-eight percent of subjects stated they would like to participate in the decision-making process of selecting an anticoagulant. Thirty-six percent of those exposed and 37% of those unexposed to anticoagulants reported that they would select a medication that has an antidote even if the risk of bleeding was very small. Twenty-three percent of the unexposed and 22% of the exposed groups reported that they would prefer the medication that gives the best quality of life.

CONCLUSION

Our study found that patients who may be exposed to an anticoagulation decision prefer to actively participate in the decision-making process, and have individual values for making a decision that cannot be predicted or assumed by anyone in the health care system.

Preferences for oral anticoagulants in atrial fibrillation: a best-best discrete choice experiment

BACKGROUND

Atrial fibrillation (AF) is recognised as a growing clinical and public health problem in many countries, owing to disability and death from stroke associated with the condition, high hospitalisation costs and an increasing prevalence with ageing populations. Under-treatment with oral anticoagulants has been a significant challenge of treatment, historically related to patient concerns over the safety and convenience of warfarin, which until recently was the only oral anticoagulant available.

OBJECTIVES

The aim of this study is to examine: (1) patient preferences for attributes of warfarin and the new oral anticoagulants (dabigatran, rivaroxaban, apixaban) in AF; (2) which attributes are most important; and (3) whether current under-treatment is likely to improve with the new oral anticoagulants.

METHODS

This study was conducted in Melbourne, Australia, with members of the general public with or without AF aged ≥40 years, where those without AF proxy for newly-diagnosed patients. Participants completed a computerised best-best discrete choice experiment (and follow-up interview) as if they had AF with a moderate-to-high risk of stroke. Choice data were modelled using mixed rank-ordered logit. Relative value was explored via estimation of marginal rates of substitution with predicted probability analysis used to simulate potential uptake of oral anticoagulants.

RESULTS

Seventy-six participants were recruited and completed the study. Efficacy (stroke risk) was more important than safety (bleed risk, antidote), which were both considerably more important than convenience factors (blood tests, dose frequency, drug or food interactions). Cost was also important. Predicted use of the new oral anticoagulants (and under-treatment of AF) using simulation, given moderate-to-high risk of stroke, is 25 % (52 %), 54 % (29 %) and 70 % (21 %) assuming a market price of AUD$120/month, AUD$30/month (subsidised price) and AUD$30/month with an antidote, respectively.

CONCLUSIONS

Based on the study sample and the modelled attributes, the overall profiles of the new oral anticoagulants were preferred to warfarin as their cost decreased. Public subsidisation and the development of antidotes (such as vitamin K for warfarin) for the new oral anticoagulants may have a positive effect on the under-treatment of AF.

Pharmacogenetic-guided selection of warfarin versus novel oral anticoagulants for stroke prevention in patients with atrial fibrillation: a cost-effectiveness analysis

OBJECTIVES

To compare clinical and economic outcomes of two anticoagulation therapy strategies, (i) pharmacogenetic-guided selection (PG-AC) of warfarin versus novel oral anticoagulants (NOACs), and (ii) usual anticoagulation care (usual AC) in patients with atrial fibrillation (AF), from the perspective of US healthcare payers.

METHODS

A Markov model was used to simulate long-term outcomes in a hypothetical cohort of 65-year-old patients with newly diagnosed AF: (i) all usual AC patients received warfarin therapy, and (ii) all PG-AC patients were genotyped. Patients with normal warfarin sensitivity genotypes would receive warfarin. Patients with high or low warfarin sensitivity genotypes would receive NOAC. Model inputs were derived from clinical trials published in the literature. The outcome measure was incremental cost per quality-adjusted life-year (QALY) gained (ICER).

RESULTS

PG-AC gained higher QALYs with higher cost (9.912 QALYs and USD94 396) when compared with usual AC (9.721 QALYs and USD93 853) in base-case analysis. The ICER of PG-AC was 2843 USD/QALY. The ICER of PG-AC would exceed 50 000 USD/QALY if the monthly cost of NOAC was more than USD285 or the risk of stroke with NOAC versus warfarin was more than 0.93. In 10 000 Monte Carlo simulations, PG-AC was cost-effective 96.4% of the time and usual AC was cost-effective 3.6% of the time. PG-AC was more costly than usual AC with a mean cost difference of USD1927 (95% confidence interval 1.877-1.977, P<0.001), and gained higher QALYs by 0.209 (95% confidence interval 0.208-0.210, P<0.001).

CONCLUSION

Compared with warfarin therapy with time in therapeutic range of 60%, using genotype to triage AF patients to warfarin or NOAC appears to be highly cost-effective.

Cost-effectiveness of clopidogrel-aspirin versus aspirin alone for acute transient ischemic attack and minor stroke

Background

Treatment with the combination of clopidogrel and aspirin taken soon after a transient ischemic attack (TIA) or minor stroke was shown to reduce the 90‐day risk of stroke in a large trial in China, but the cost‐effectiveness is unknown. This study sought to estimate the cost‐effectiveness of the clopidogrel‐aspirin regimen for acute TIA or minor stroke.

Methods and Results

A Markov model was created to determine the cost‐effectiveness of treatment of acute TIA or minor stroke patients with clopidogrel‐aspirin compared with aspirin alone. Inputs for the model were obtained from clinical trial data, claims databases, and the published literature. The main outcome measure was cost per quality‐adjusted life‐years (QALYs) gained. One‐way and multivariable probabilistic sensitivity analyses were performed to test the robustness of the findings. Compared with aspirin alone, clopidogrel‐aspirin resulted in a lifetime gain of 0.037 QALYs at an additional cost of CNY 1250 (US$ 192), yielding an incremental cost‐effectiveness ratio of CNY 33 800 (US$ 5200) per QALY gained. Probabilistic sensitivity analysis showed that clopidogrel‐aspirin therapy was more cost‐effective in 95.7% of the simulations at a willingness‐to‐pay threshold recommended by the World Health Organization of CNY 105 000 (US$ 16 200) per QALY.

Conclusions

Early 90‐day clopidogrel‐aspirin regimen for acute TIA or minor stroke is highly cost‐effective in China. Although clopidogrel is generic, Plavix is brand in China. If Plavix were generic, treatment with clopidogrel‐aspirin would have been cost saving.

Novel oral anticoagulants versus warfarin therapy at various levels of anticoagulation control in atrial fibrillation--a cost-effectiveness analysis

BACKGROUND

The decision as to whether to use more expensive novel oral anticoagulants (NOACs) or invest resources for quality improvement of warfarin therapy requires input from both clinical and economic analyses.

OBJECTIVE

Cost-effectiveness of NOACs compared to warfarin therapy at various levels of patient-time in therapeutic range (TTR) in patients with atrial fibrillation was examined, from the healthcare provider's perspective.

DESIGN, SUBJECTS AND INTERVENTION

A Markov model was used to compare life-long economic and treatment outcomes of warfarin and NOACs in a hypothetical cohort of 65-year-old atrial fibrillation patients with CHADS2 scores of 2 or above. Model inputs were derived from clinical trials published in the literature.

MAIN MEASURES

The outcome measure was incremental cost per quality-adjusted life-year (QALY) gained (ICER).

KEY RESULTS

Using United States Dollar (USD) 50,000 as the threshold of willingness-to-pay per QALY, NOACs therapy was cost-effective when TTR of warfarin therapy was 60 % or below, or monthly cost of warfarin management increased by two-fold or more to achieve 70 % TTR. Warfarin therapy was cost-effective when TTR of warfarin was 70 % with up to a 1.5-fold increment in monthly cost of care, or when TTR reached 75 % with monthly cost of warfarin care increased up to three-fold. At TTR 60 %, 70 % and 75 %, NOACs was cost-effective when monthly drug cost was < USD 200, < USD 122-185 and < USD 85-145, respectively. 10,000 Monte Carlo simulations showed NOACs to be cost-effective 83.6 %, 50.7 % and 32.7 % of the time at TTR of 60 %, 70 % and 75 %, respectively.

CONCLUSIONS

The acceptance of NOACs as cost-effective was highly dependent upon drug cost, anticoagulation control for warfarin, and anticoagulation service cost.

Evaluation of patients' attitudes towards stroke prevention and bleeding risk in atrial fibrillation

Patient's values and preferences regarding the relative importance of preventing strokes and avoiding bleeding are now recognised to be of great importance in deciding on therapy for the prevention of stroke due to atrial fibrillation (SPAF). We used an iPad questionnaire to determine the minimal clinically important difference (Treatment Threshold) and the maximum number of major bleeding events that a patient would be willing to endure in order to prevent one stroke (Bleeding Ratio) for the initiation of antithrombotic therapy in 172 hospital in-patients with documented non-valvular atrial fibrillation in whom anticoagulant therapy was being considered. Patients expressed strong opinions regarding SPAF. We found that 12% of patients were "medication averse" and were not willing to consider antithrombotic therapy; even if it was 100% effective in preventing strokes. Of those patients who were willing to consider antithrombotic therapy, 42% were identified as "risk averse" and 15% were "risk tolerant". Patients required at least a 0.8% (NNT=125) annual absolute risk reduction and 15% relative risk reduction in the risk of stroke in order to agree to initiate antithrombotic therapy, and patients were willing to endure 4.4 major bleeds in order to prevent one stroke. In conclusion, there was a substantial amount of inter-patient variability, and often extreme differences in opinion regarding tolerance of bleeding risk in the context of stroke prevention in atrial fibrillation. These findings highlight the importance of considering patient preferences when deciding on SPAF therapy.

Anti-coagulation, anti-platelets or no therapy in haemodialysis patients with atrial fibrillation: A decision analysis

BACKGROUND

Optimal treatment of atrial fibrillation (AF) in the haemodialysis population is uncertain due to the exclusion of this group from randomized trials. The risk-benefit profile for anticoagulation and anti-platelet therapy in haemodialysis differs from the general population due to platelet dysfunction from uraemia, altered pharmacokinetics and increased falls risk.

METHODS

This decision analysis used a Markov-state transition model that took a patient perspective over a 5 year timeframe. The Markov model compared life-years gained and quality-adjusted life-years gained (QALY) for three AF treatment strategies: warfarin, aspirin and no treatment. The base case was a 70-year-old man on haemodialysis with non-valvular AF.

RESULTS

In the base case, the total health outcomes in life-years and QALY were 2.37 and 1.47 respectively for warfarin, 2.38 and 1.61 respectively for aspirin, and 2.39 and 1.61 respectively for no treatment. Thus, warfarin led to 0.14 fewer QALY or 1.7 fewer months of life lived in full health, compared with either aspirin or no therapy. The finding that warfarin generated the lowest expected QALY was robust to one-way, two-way and probabilistic sensitivity analyses.

CONCLUSIONS

Our results suggest that warfarin should not be the default choice for older haemodialysis patients with non-valvular AF as it provides the fewest QALY compared with aspirin or no therapy.

Potential impact of new oral anticoagulants on the management of atrial fibrillation-related stroke in primary care

AIM

Anticoagulant prophylaxis with vitamin K antagonists (such as warfarin) is effective in reducing the risk of stroke in patients with atrial fibrillation (AF). New oral anticoagulants have emerged as potential alternatives to traditional oral agents. The purpose of this review was to summarise the effectiveness and safety of rivaroxaban, dabigatran and apixaban in stroke prevention in patients with AF in phase III trials, evaluate their cost-effectiveness and consider the implications for primary care.

METHODOLOGY

A literature search was performed between 2007 and 2012, selecting all phase III trials (ROCKET AF, RE-LY and ARISTOTLE) of new oral anticoagulants and relevant cost-benefit studies.

RESULTS

Evidence shows that all three agents are at least as effective as warfarin in the prevention of stroke and systemic emboli, with similar safety profiles. Cost-benefit studies of rivaroxaban and dabigatran further confirm their potential use as alternatives to warfarin in clinical practice. These observations may allow stratification of the general practice AF population, to help prioritise which patients may benefit from receiving a new oral anticoagulant.

CONCLUSION

The clinical and economic benefits of the new oral anticoagulants, along with appropriate risk stratification, may enable a higher number of patients with AF to receive effective and convenient prophylaxis for stroke prevention.

Economic evaluation of percutaneous left atrial appendage occlusion, dabigatran, and warfarin for stroke prevention in patients with nonvalvular atrial fibrillation

BACKGROUND

Percutaneous left atrial appendage (LAA) occlusion and novel pharmacological therapies are now available to manage stroke risk in patients with nonvalvular atrial fibrillation; however, the cost-effectiveness of LAA occlusion compared with dabigatran and warfarin in patients with nonvalvular atrial fibrillation is unknown.

METHODS AND RESULTS

Cost-utility analysis using a patient-level Markov microsimulation decision analytic model with a lifetime horizon was undertaken to determine the lifetime costs, quality-adjusted life years, and incremental cost-effectiveness ratio of LAA occlusion in relation to dabigatran and warfarin in patients with nonvalvular atrial fibrillation at risk for stroke without contraindications to oral anticoagulation. The analysis was performed from the perspective of the Ontario Ministry of Health and Long Term Care, the third-party payer for insured health services in Ontario, Canada. Effectiveness and utility data were obtained from the published literature. Cost data were obtained from the Ontario Drug Benefits Formulary and the Ontario Case Costing Initiative. Warfarin therapy had the lowest discounted quality-adjusted life years at 4.55, followed by dabigatran at 4.64 and LAA occlusion at 4.68. The average discounted lifetime cost was $21 429 for a patient taking warfarin, $25 760 for a patient taking dabigatran, and $27 003 for LAA occlusion. Compared with warfarin, the incremental cost-effectiveness ratio for LAA occlusion was $41 565. Dabigatran was extendedly dominated.

CONCLUSIONS

Percutaneous LAA occlusion represents a novel therapy for stroke reduction that is cost-effective compared with warfarin for patients at risk who have nonvalvular atrial fibrillation.

Applying evidence to patient care: from population health to individual patient values

What are the health status and health needs of people with epilepsy? How do clinicians and patients choose between alternative interventions for the same condition? Are health interventions used effectively in the community, and do they improve health? How can we translate findings from regulatory clinical trials to the real world? These and similar questions are the subject of applied translational research. This evolving and broad-ranging area of research involves the application of basic sciences such as epidemiology, biostatistics, economics, and behavioral science to the assessment of health, health interventions, and outcomes. However, despite its palpable importance, applied translational research remains underfunded and underutilized. Using their own innovative research as a prototype, two young and promising investigators provide insights not only into the enormous potential but also the gaps and hurdles of two specific areas of applied translational research, i.e., clinical decision analysis and health services research. The message is clear that if we are to understand and improve the health of people with epilepsy in clinics, hospitals, and communities, we must substantially increase research capacity to address the many gaps that thwart our progress in applied research in epilepsy.

Incorporating the patient perspective: a critical review of clinical practice guidelines for implantable cardioverter defibrillator therapy

PURPOSE

Implantable cardioverter defibrillators (ICDs) are recommended for patients with heart failure and/or ventricular arrhythmias at risk of sudden cardiac death. Guidelines for ICD implantation are derived from robust clinical data. However, critical factors which might influence treatment decisions include patient preferences. We set out to determine how clinical practice guidelines (CPGs) incorporate the patient perspective into supporting decision making about ICDs.

METHODS

CPGs on ICD implantation were purposively selected from national and professional bodies in Europe, North America and Australasia. CPGs were then appraised according to three key domains of shared decision making: (a) informing patients about the risks, benefits and consequences known to be important to patients; (b) personalising risks and benefits and (c) involvement of patient (plus family/significant others if desired) in decision making.

RESULTS

Appraisal of six current CPGs found major deficiencies or inconsistencies in guidance. CPGs tended to focus on evidence of device effectiveness, with sparse consideration of other outcomes important to patients such as impacts on quality of life and psychosocial well-being. Little reference was made to involvement of the patient in decision making.

CONCLUSIONS

This suggests that embedding shared decision in CPGs will improve the patient-centeredness of ICD treatment by enabling patients to make informed, value-based decisions. Specific recommendations for CPG development include the need for signposting to preference sensitive decision points as well as inclusion of a broader range of outcomes which are known to be important to patients when deciding whether or not to have a device fitted.

Cost-effectiveness of apixaban compared with warfarin for stroke prevention in atrial fibrillation

BACKGROUND

Apixaban was shown to be superior to adjusted-dose warfarin in preventing stroke or systemic embolism in patients with atrial fibrillation (AF) and at least one additional risk factor for stroke, and associated with reduced rates of hemorrhage. We sought to determine the cost-effectiveness of using apixaban for stroke prevention.

METHODS

Based on the results from the Apixaban Versus Warfarin in Patients with Atrial Fibrillation (ARISTOTLE) trial and other published studies, we constructed a Markov model to evaluate the cost-effectiveness of apixaban versus warfarin from the Medicare perspective. The base-case analysis assumed a cohort of 65-year-old patients with a CHADS(2) score of 2.1 and no contraindication to oral anticoagulation. We utilized a 2-week cycle length and a lifetime time horizon. Outcome measures included costs in 2012 US$, quality-adjusted life-years (QALYs), life years saved and incremental cost-effectiveness ratios.

RESULTS

Under base case conditions, quality adjusted life expectancy was 10.69 and 11.16 years for warfarin and apixaban, respectively. Total costs were $94,941 for warfarin and $86,007 for apixaban, demonstrating apixaban to be a dominant economic strategy. Upon one-way sensitivity analysis, these results were sensitive to variability in the drug cost of apixaban and various intracranial hemorrhage related variables. In Monte Carlo simulation, apixaban was a dominant strategy in 57% of 10,000 simulations and cost-effective in 98% at a willingness-to-pay threshold of $50,000 per QALY.

CONCLUSIONS

In patients with AF and at least one additional risk factor for stroke and a baseline risk of ICH risk of about 0.8%, treatment with apixaban may be a cost-effective alternative to warfarin.

Cost-effectiveness of rivaroxaban compared to warfarin for stroke prevention in atrial fibrillation

Rivaroxaban has been found to be noninferior to warfarin for preventing stroke or systemic embolism in patients with high-risk atrial fibrillation (AF) and is associated with a lower rate of intracranial hemorrhage. To assess the cost-effectiveness of rivaroxaban compared to adjusted-dose warfarin for the prevention of stroke in patients with AF, we built a Markov model using a United States payer/Medicare perspective and a lifetime time horizon. The base-case analysis assumed a cohort of patients with AF 65 years of age with a congestive heart failure, hypertension, age, diabetes, stroke (2 points) score of 3 and no contraindications to anticoagulation. Data sources included the 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 other studies of anticoagulation. Outcome measurements included costs in 2011 United States dollars, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs). Patients with AF treated with rivaroxaban lived an average of 10.03 QALYs at a lifetime treatment cost of $94,456. Those receiving warfarin lived an average of 9.81 QALYs and incurred costs of $88,544. The ICER for rivaroxaban was $27,498 per QALY. These results were most sensitive to changes in the hazard decrease of intracranial hemorrhage and stroke with rivaroxaban, cost of rivaroxaban, and time horizon. Monte Carlo simulation demonstrated rivaroxaban was cost-effective in 80% and 91% of 10,000 iterations at willingness-to-pay thresholds of $50,000 and $100,000 per QALY, respectively. In conclusion, this Markov model suggests that rivaroxaban therapy may be a cost-effective alternative to adjusted-dose warfarin for stroke prevention in AF.