Barriers to anticoagulation in patients with atrial fibrillation: changing physician-related factors

Implications of Clinical Risk Phenotypes on the Management and Natural History of Atrial Fibrillation: A Report From the GLORIA-AF

Background Clinical risk factors are common among patients with atrial fibrillation (AF), but there are still limited data on their association with oral anticoagulant (OAC) treatment patterns and major outcomes. We aim to analyze the association between clinical risk phenotypes on AF treatment patterns and the risk of major outcomes. Methods and Results The GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation) phase 2 and 3 registries enrolled patients with a recent diagnosis of AF between 2011 and 2016. We defined 4 features of clinical risk among patients with CHA2DS2-VASc ≥2: elderly individuals (aged ≥80 years), chronic kidney disease (estimated glomerular filtration rate <45 mL/min), history of stroke, and history of bleeding. We analyzed the odds of receiving OAC and the risk of OAC discontinuation and adverse events at follow-up according to specific combinations and cumulative burden of these features. Primary outcome was the composite of all-cause death, thromboembolism, and major bleeding. Among 28 891 (mean±SD age, 70.1±10.5 years; 45.5% women) patients included, 10 797 (37.3%) had at least 1 clinical risk feature. OAC use was lower among patients in the elderly group (odds ratio [OR], 0.85 [95% CI, 0.75-0.96]), those with history of both stroke and bleeding (OR, 0.45 [95% CI, 0.35-0.56]), and those with multiple features (OR, 0.71 [95% CI, 0.62-0.82]). Increasing burden of clinical risk features was associated with OAC discontinuation, with highest magnitude in those with ≥3 features (hazard ratio [HR], 1.68 [95% CI, 1.31-2.15]). Groups with increasingly complex clinical risk phenotypes were associated with the occurrence of the primary composite outcome, with the highest figures observed for groups with a history of both stroke and bleeding (adjusted HR, 2.36 [95% CI, 1.83-3.04]) and multiple features (adjusted HR, 2.86 [95% CI, 2.52-3.25]). Conclusions In patients with AF, clinical risk phenotypes are multifaceted and heterogenous, and they are associated with differences in stroke prevention and worse prognosis.

Integrated Care in Atrial Fibrillation: A Road Map to the Future

Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice with an epidemiological coupling appreciated with advancing age, cardiometabolic risk factors, and structural heart disease. This has resulted in a significant public health burden over the years, evident through increasing rates of hospitalization and AF-related clinical encounters. The resultant gap in health care outcomes is largely twinned with suboptimal rates of anticoagulation prescription and adherence, deficits in symptom identification and management, and insufficient comorbid cardiovascular risk factor investigation and modification. In view of these shortfalls in care, the establishment of integrated chronic care models serves as a road map to best clinical practice. The expansion of integrated chronic care programs, which include multidisciplinary team care, nurse-led AF clinics, and use of telemedicine, are expected to improve AF-related outcomes in the coming years. This review will delve into current gaps in AF care and the role of integrated chronic care models in bridging fragmentations in its management.

A Real-world Experience of the Safety and Efficacy of Non-vitamin K Oral Anticoagulants Versus Warfarin in Patients with Non-valvular Atrial Fibrillation— A Single-centre Retrospective Cohort Study in Singapore

Introduction: Non-vitamin K oral anticoagulants (NOACs) were shown to have better outcomes than warfarin for non-valvular atrial fibrillation (NVAF). Given limited local real-world data, this study aims to evaluate the safety and efficacy of NOACs versus warfarin for NVAF in Singapore. Methods: This single-centre retrospective cohort study included 439 patients ≥ 21 years old that were newly prescribed with oral anticoagulants (OACs) for NVAF in 2015. Follow-ups for patients upon OAC initiation lasted either for 2 years or until the occurrence of bleeding or thromboembolism event or death (whichever was earlier). Primary endpoints included major bleeding and stroke, while secondary endpoints included overall bleeding and thromboembolic events. Time-to-events was evaluated via Kaplan-Meier survival analysis. Data on time in therapeutic range (TTR) and compliance were analysed. Results: Patients were assigned to 4 groups: warfarin (157, 35.8%), rivaroxaban (154, 35.1%), apixaban (98, 22.3%) and dabigatran (30, 6.8%). With a mean age of 70.8 (±10.8) years old, the population were predominantly males (56.5%) and comprised Chinese (73.8%), Malays (18.7%) and others (7.5%). The rates of stroke per year were 0.7%, 1.7%, 2.2% and 0% for warfarin, rivaroxaban, apixaban and dabigatran, respectively (P=0.411), whereas those of major bleeding were 2.7%, 1.4%, 2.2% and 0% (P=0.560). As compared to warfarin, no significant differences were observed for risks of stroke and of major bleeding for rivaroxaban (adjusted hazard ratio (HR) 4.19, 95% confidence interval (CI) 0.68–26.05, P=0.124 and adjusted HR 0.43, 95% CI 0.12–1.59, P=0.207) and apixaban (adjusted HR 5.33, 95% CI 0.85–33.34, P=0.074 and adjusted HR 1.54, 95% CI 0.39–6.15, P=0.538). Mean TTR was 68.8% (±24.3%) for warfarin. Compliance rates for rivaroxaban, apixaban, and dabigatran were 56.6%, 59.2%, and 44.8% respectively (P=0.177). Conclusion: NOACs were associated with similar stroke and major bleeding rates as warfarin for NVAF. Keywords: Anticoagulant, Asian, atrial fibrillation, compliance, haemorrhage, thrombosis

Trajectories of Oral Anticoagulation Adherence Among Medicare Beneficiaries Newly Diagnosed With Atrial Fibrillation

Background

Only 50% of atrial fibrillation (AF) patients recommended for oral anticoagulation (OAC) use these medications, and less than half of them adhere to OAC. In a cohort of Medicare beneficiaries newly diagnosed with AF, we identified groups of patients with similar trajectories of OAC use and adherence, and evaluated patient characteristics affecting group membership.

Methods and Results

We selected continuously enrolled Medicare Part D beneficiaries with first AF diagnosis in 2014 to 2015 (n=34 898). We calculated the proportion of days covered with OAC over the first 12 months after diagnosis and identified OAC adherence trajectories using group‐based trajectory models. We constructed multinomial logistic regression models to evaluate how demographics, system‐level factors, and clinical characteristics were associated with group membership. We identified 4 trajectories of OAC adherence: patients who never used OAC (43.8%), late OAC initiators (7.6%), early OAC discontinuers (8.9%), and continuously adherent patients (40.1%). Predictors such as sex, black race, residence in the South, or HAS‐BLED score were associated with not only OAC use, but also the timing of initiation and the likelihood of discontinuation. For example, HAS‐BLED score ≥4 was associated with a higher likelihood of not using OAC (odds ratio 1.35; 95% CI, 1.14–1.62), of late initiation (1.55; 95% CI, 1.11–2.05), and of early discontinuation (odds ratio 1.35; 95% CI, 1.01–1.84).

Conclusions

We identified 4 distinct trajectories of OAC adherence after first AF diagnosis, with <45% of newly diagnosed AF patients belonging to the trajectory group characterized by continuous OAC adherence. Trajectories were associated not only with demographic and clinical characteristics but also with regional factors.

Real-life Performance of Edoxaban in Elderly Patients With Atrial Fibrillation: a Multicenter Propensity Score-Matched Cohort Study

PURPOSE

The purpose of the current study was to compare the efficacy and safety of edoxaban versus vitamin K antagonist (VKA) therapy among a cohort of elderly patients (ie, those aged ≥75 years) with atrial fibrillation (AF) in a real-life setting.

METHODS

A propensity score-matched cohort observational study was performed comparing the safety and efficacy of edoxaban versus VKA therapy among a cohort of elderly (aged ≥75 years) patients with AF in a real-life setting. Follow-up data were obtained through outpatient visits at 1, 3, and every 6 months. The primary safety outcome was major bleeding. The primary efficacy outcome was the composite of stroke, transient ischemic attack, and systemic embolism.

FINDINGS

A total of 130 patients receiving edoxaban 60 mg (EDO) treatment were compared with the same number of VKA recipients. The mean follow-up was 16 (2.6) months. The cumulative incidence of thromboembolic events in the EDO and VKA groups was 1.5% (2 of 130) and 2.3% (3 of 130), respectively (P < 0.6). The cumulative incidence of major bleeding events was 1.5% (2 of 130) in the EDO group and 3.1% (4 of 130) in the VKA group (P < 0.4). The total anticoagulant therapy discontinuation rate was 2.3% (3 of 130) in the EDO group and 4.6% (6 of 130) in the VKA group (P < 0.3). A nonsignificant trend in improved adherence was observed between the EDO and VKA groups (81% vs 78%; P = 0.6).

IMPLICATIONS

Edoxaban therapy showed a good real-life performance among elderly patients (aged ≥75 years) with AF.

Impact of the type of centre on management of AF patients: Surprising evidence for differences in antithrombotic therapy decisions

Atrial fibrillation (AF) patients may receive treatment from specialists or from general medicine physicians representing different levels of care within a structured health care system. This “choice” is influenced by patient flow within a health care system, patient preference, and individual access to health care resources. We analysed how the postgraduate training and work environment of treating physicians affects management decisions in AF patients. Patient characteristics and treatment decisions were analysed at the time of enrolment into the registry of the German Atrial Fibrillation NETwork (AFNET). A total of 9,577 patients were enrolled from 2004 to 2006 in 191 German centres that belonged to the following four levels of care: 13 tertiary care centres (TCC) enrolled 3,795 patients (39.6%), 58 district hospitals (DH) enrolled 2,339 patients (24.4%), 62 office-based cardiologists (OC) enrolled 2,640 patients (27.6%), and 58 general practitioners or internists (GP) enrolled 803 patients (8.4%). Patients with new-onset AF were often treated in DH. TCC treated younger patients who more often presented with paroxysmal AF. Older patients and patients in permanent AF more often received outpatient care. Consistent with recommendations, younger patients and patients with non-permanent AF received rhythm control therapy more often. In addition, the type of centre affected the decision for rhythm control. Stroke risk was similar between centre types (mean CHADS2 scores 1.6 –1.9). TCC (68.8%) and OC (73.6%) administered adequate antithrombotic therapy more often than DH (55.1%) or GP (52.0%, p<0.001 between groups). Upon multivariate analysis, enrolment by TCC or OC was associated with a 1.60 (1.20–2.12, p=0.001) fold chance for adequate antithrombotic treatment. This difference between centre types was consistent irrespective of the type of stroke risk estimation (ESC 2001 guidelines, CHADS2 score), and also consistent when the recently suggested CHA2DS2-VASc score was used to estimate stroke risk. In conclusion, management decisions in AF are influenced by the education and clinical background of treating physicians in Germany. Inpatients receive more rhythm control therapy. Adequate antithrombotic therapy is more often administered in specialist (cardiologist) centres.

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.

Reducing the risk of stroke in elderly patients with non-valvular atrial fibrillation: a practical guide for clinicians

Non-valvular atrial fibrillation (NVAF) significantly contributes to the burden of stroke, particularly in elderly patients. The challenge of optimizing anticoagulation therapy is balancing efficacy and bleeding risk, especially as the same patients at high risk of stroke also tend to be at high risk of bleeding. Treating the elderly patient with NVAF presents special challenges because of their heightened risk for both stroke and bleeding. Despite clinical trial data and evidence-based guidelines, surveys indicate that physicians underuse anticoagulation in older patients for reasons that include overemphasis of bleeding risk, particularly with the increased risk of falling, at the cost of thromboembolic risk. Clinical trial data are now available, and real-world data are emerging, to illustrate the relative merits of the non-vitamin K antagonist oral anticoagulants compared with conventional anticoagulation in the treatment of elderly patients with this condition, and to suggest some subgroups of older patients who may be more suitable candidates for particular agents. Care of elderly patients with NVAF is often complicated by factors including risk of falling, adherence, health literacy, cognitive function, adverse effects, and involvement of caregivers, as well as other factors including the patient–provider relationship and logistical barriers to obtaining medication. Thus, conversations between clinicians and patients, as well as shared decision making, are important. In addition, elderly patients often suffer from comorbidities including hypertension, coronary heart disease, diabetes mellitus, COPD, and/or heart failure, which necessitate the use of multiple concomitant medications, increasing the risk of drug/drug interactions. This review provides an overview of clinical trial data on the use of non-vitamin K anticoagulant agents in elderly populations, and serves as a practical resource for the management of NVAF in the elderly patient.

Impact of a Computerized Antithrombotic Risk Assessment Tool on the Prescription of Thromboprophylaxis in Atrial Fibrillation: Hospital Setting

The computerized antithrombotic risk assessment tool (CARAT) is an online decision-support algorithm that facilitates a systematic review of a patient's stroke risk, bleeding risk, and pertinent medication safety considerations, to generate an individualized treatment recommendation. The CARAT was prospectively applied across 2 hospitals in the greater Sydney area. Its impact on antithrombotics utilization for thromboprophylaxis in patients with nonvalvular atrial fibrillation was evaluated. Factors influencing prescribers' treatment selection were identified. The CARAT recommended a change in baseline therapy for 51.8% of patients. Among anticoagulant-eligible patients (ie, where the risk of stroke outweighed the risk of bleeding) using "nil therapy" or antiplatelet therapy at baseline, the CARAT recommended an upgrade to warfarin in 60 (30.8%) patients. For those in whom the bleeding risk outweighed the stroke risk, the CARAT recommended a downgrade from warfarin to safer alternatives (eg, aspirin) in 37 (19%) patients. Among the "most eligible" (ie, high stroke risk, low bleeding risk, no contraindications; n = 75), the CARAT recommended warfarin for all cases. Discharge therapy observed a marginal increase in anticoagulation prescription in eligible patients (n = 116; 57.8% vs 64.7%, P = .35) compared to baseline. Predictors of warfarin use (vs antiplatelets) included congestive cardiac failure, diabetes mellitus, and polypharmacy. The CARAT was able to optimize the selection of therapy, increasing anticoagulant use among eligible patients. With the increasing complexity of decision-making, such tools may be useful adjuncts in therapy selection in atrial fibrillation. Future studies should explore the utility of such tools in selecting therapies from within an expanded treatment armamentarium comprising the non-vitamin K antagonist oral anticoagulants.

Oral anticoagulant therapy in atrial fibrillation patients at high stroke and bleeding risk

Atrial fibrillation (AF) is associated with a 5-fold greater risk of ischemic stroke or systemic embolism compared with normal sinus rhythm. Cardioembolic AF-related strokes are often more severe, fatal or associated with greater permanent disability and higher recurrence rates than strokes of other aetiologies. These strokes may be effectively prevented with oral anticoagulant (OAC) therapy, using either vitamin K antagonists (VKAs) or non-vitamin K antagonist OACs (NOACs) such as the direct thrombin inhibitor dabigatran or direct factor Xa inhibitors rivaroxaban, apixaban or edoxaban. Most AF patients have a positive net clinical benefit from OAC, excluding those with AF and no conventional stroke risk factors. Balancing the risks of stroke and bleeding is necessary for optimal use of OAC in clinical practice, and modifiable bleeding risk factors must be addressed. Concerns remain over 'non-changeable' bleeding risk factors such as older age, significant renal or hepatic impairment, prior stroke(s) or prior bleeding event(s) and active malignancies. Such AF patients are often termed 'special' AF populations, due to their 'special' risk profile that includes increased risks of both thromboembolic and bleeding events, and due to fear of bleeding complications these AF patients are often denied OAC. Evidence shows, however, that the absolute benefits of OAC are the greatest in patients at the highest risk, and NOACs may offer even a greater net clinical benefit compared to warfarin particularly in these high risk patients. In this review article, we summarize available data on stroke prevention in AF patients at increased risk of both stroke and bleeding and discuss the use of NOACs for thromboprophylaxis in these 'special' AF populations.

Practical considerations in the use of novel oral anticoagulants for stroke prevention in nonvalvular atrial fibrillation

Atrial fibrillation (AF) is a highly prevalent cardiac arrhythmia associated with an increased risk of stroke. The role of anticoagulation therapy in the prevention of thrombosis and stroke is of critical importance for patients with AF. Limitations with vitamin K antagonists (VKAs), the current standard of care, have led to the development of novel oral anticoagulants (NOACs) that target either thrombin (dabigatran etexilate) or activated factor X (rivaroxaban, apixaban, and edoxaban). In comparison with traditional VKAs such as warfarin, these NOACs offer several pharmacologic advantages, including rapid onset of action, no significant food interactions, low potential for drug-drug interactions, and no requirement for routine coagulation monitoring. Completed phase-III clinical trials have demonstrated the therapeutic potential of dabigatran, rivaroxaban, and apixaban in comparison with warfarin for stroke prevention in patients with nonvalvular AF (NVAF). While the future utility of NOACs in preventing stroke in patients with NVAF looks promising, several practical issues, including the current lack of a reversal strategy and use of these agents in older patients with renal dysfunction, must be considered. Clinician and patient understanding of such issues will be important for the safe and effective use of NOACs.

Evaluation of practice patterns in the treatment of atrial fibrillation among the commercially insured

OBJECTIVE

The management of atrial fibrillation (AF) involves two choices: (1) rate control versus rhythm control, and (2) anticoagulation treatment based upon risk of stroke. The objective of the study was to describe practice patterns in both of these treatment areas in patients with newly diagnosed AF among a commercially insured population.

METHODS

This retrospective administrative claims analysis included patients with ≥2 AF claims between 1 January 2008 and 30 September 2010. Patients with AF claims within a year prior to the index date (i.e., the first AF diagnosis date) were excluded. The primary outcome was the proportion of patients treated with rate control (i.e., beta blockers, calcium channel blockers, digoxin) versus rhythm control (i.e., electrical cardioversion, left atrial catheter ablation [LACA], and/or surgical ablation) and the use of anticoagulants stratified by risk of stroke based on CHADS2 score.

RESULTS

Of 48,814 patients with a diagnosis of AF, 38,502 (78.9%) received treatment. Of those treated, the majority received only pharmacologic treatment (73.4%), of which beta blockers were predominantly used in the initial regimen (66.7%). Antiarrhythmic drugs were used in 23.9% of patients, but within the initial regimen in only 11.7% of patients. Direct current cardioversion occurred in 18.2% of patients, with the majority being either first-line (8.5%) or second-line (9.1%) therapy. LACA was used in only 5.2% of patients and was typically reserved for use after pharmacologic treatment or direct current cardioversion. Of 1924 patients who received LACA, 14.6% received a repeat procedure and 53.4% of the repeat procedures occurred within 6 months of the initial one. A little more than half of all patients (57.0%) received anticoagulant therapy (predominantly warfarin); of those at high risk for stroke, 63.8% with a CHADS2 score ≥2 received anticoagulants.

KEY LIMITATIONS

It is a retrospective analysis using administrative claims data from a commercially insured population only. Identification of the first episode of AF may be inaccurate, and we cannot differentiate between paroxysmal and persistent AF.

CONCLUSIONS

Debate continues regarding whether the preferred management of most patients with AF is through rate control or restoration of normal sinus rhythm. Our retrospective study found that treatments to restore normal heart rhythm, including LACA, which could be considered aggressive initial treatment, were typically reserved as second- or third-line alternatives. Initial standard of care for the majority patients was beta blockers. Though use of anticoagulation may be higher than other observational studies, opportunities exist to increase treatment in high risk patients.

Anticoagulant use for the prevention of stroke in patients with atrial fibrillation: findings from a multi-payer analysis

Background

Oral anticoagulation is recommended for stroke prevention in intermediate/high stroke risk atrial fibrillation (AF) patients. The objective of this study was to demonstrate the usefulness of analytic software tools for descriptive analyses of disease management in atrial AF; a secondary objective is to demonstrate patterns of potential anticoagulant undertreatment in AF.

Methods

Retrospective data analyses were performed using the Anticoagulant Quality Improvement Analyzer (AQuIA), a software tool designed to analyze health plan data. Two-year data from five databases were analyzed: IMS LifeLink (IMS), MarketScan Commercial (MarketScanCommercial), MarketScan Medicare Supplemental (MarketScanMedicare), Clinformatics™ DataMart, a product of OptumInsight Life Sciences (Optum), and a Medicaid Database (Medicaid). Included patients were ≥ 18 years old with a new or existing diagnosis of AF. The first observed AF diagnosis constituted the index date, with patient outcomes assessed over a one year period. Key study measures included stroke risk level, anticoagulant use, and frequency of International Normalized Ratio (INR) monitoring.

Results

High stroke risk (CHADS₂ ≥ 2 points) was estimated in 54% (IMS), 22% (MarketScanCommercial), 64% (MarketscanMedicare), 42% (Optum) and 62% (Medicaid) of the total eligible population. Overall, 35%, 29%, 38%, 39% and 16% of all AF patients received an anticoagulant medication in IMS, MarketScanCommercial, MarketScanMedicare, Optum and Medicaid, respectively. Among patients at high risk for stroke, 19% to 51% received any anticoagulant.

Conclusions

The AQuIA provided a consistent platform for analysis across multiple AF populations with varying baseline characteristics. Analyzer results show that many high-risk AF patients in selected commercial, Medicare-eligible, and Medicaid populations do not receive appropriate thromboprophylaxis, as recommended by treatment guidelines.

Impact of stated barriers on proposed warfarin prescription for atrial fibrillation: a survey of Canadian physicians

BACKGROUND

Atrial fibrillation (AF) is a common cardiac arrhythmia, and leading cause of ischemic stroke. Despite proven effectiveness, warfarin remains an under-used treatment in atrial fibrillation patients. We sought to study, across three physician specialties, a range of factors that have been argued to have a disproportionate effect on treatment decisions.

METHODS

Cross-sectional survey of Canadian Family Doctors (FD: n = 500), Geriatricians (G: n = 149), and Internal Medicine specialists (IMS: n = 500). Of these, 1032 physicians were contactable, and 335 completed and usable responses were received. Survey questions and clinical vignettes asked about the frequency with which they see patients with atrial fibrillation, treatment practices, and barriers to the prescription of anticoagulants.

RESULTS

Stated prescribing practices did not significantly differ between physician groups. Falls risk, bleeding risk and poor patient adherence were all highly cited barriers to prescribing warfarin. Fewer geriatricians indicated that history of patient falls would be a reason for not treating with warfarin (G: 47%; FD: 71%; IMS: 72%), and significantly fewer changed reported practice in the presence of falls risk (χ (2) (6) = 45.446, p < 0.01). Experience of a patient having a stroke whilst not on warfarin had a significant impact on vignette decisions; physicians who had had patients who experienced a stroke were more likely to prescribe warfarin (χ (2) (3) =10.7, p = 0.013).

CONCLUSIONS

Barriers to treatment of atrial fibrillation with warfarin affect physician specialties to different extents. Prior experience of a patient suffering a stroke when not prescribed warfarin is positively associated with intention to prescribe warfarin, even in the presence of falls risk.

A non-experimental study of oral anticoagulation therapy initiation before and after national patient safety goals

OBJECTIVES

The Joint Commission revised its National Patient Safety Goals (NPSGs) to include oral anticoagulation therapy (OAT) in 2008. We sought to examine the effect of including OAT in The Joint Commission's NPSGs on historically low rates of OAT initiation for individuals with incident atrial fibrillation (AF).

SETTING

Southeastern state in the USA.

PARTICIPANTS

North Carolina State Health Plan claims data from 944 500 individuals enrolled between 1 January 2006 and 31 December 2010, supplemented with data from the Area Resource File and Online Survey, Certification and Reporting data network. We evaluated OAT initiation before and after the 2008 NPSGs revisions in a retrospective cohort new user design with an AF intervention group and two control groups: a positive control-patients estimated to be at very high risk of thromboembolism (mechanical heart valve and pulmonary embolism); and a negative control-patients with very low perceived risk of thromboembolism (paroxysmal AF). We developed multivariable models using a difference-in-difference parameterisation. Effects were estimated with generalised estimating equations.

PRIMARY OUTCOME MEASURE

OAT initiation, a binary outcome defined as having a prescription drug claim for warfarin within 30 days of the index claim.

RESULTS

OAT initiation was low (26.8%) for eligible individuals with incident AF in 2006-2008 but increased after NPSGs implementation (31.7%, p=0.022). OAT initiation was high but decreased in the positive control group (67.5% vs 62.0%, p=0.003). Multivariate analysis resulted in a relative 11% (95% CI (4% to 18%), p<0.01) increase in OAT initiation for incident AF patients.

CONCLUSIONS

We document a substantial increase in guideline concordant OAT initiation in incident AF after the establishment of NPSGs, suggesting that regulatory healthcare agency initiatives can influence clinical practice.

Patient-centered medical homes and oral anticoagulation therapy initiation

Despite evidence-based guidelines, oral anticoagulation therapy (OAT) initiation is low among incident atrial fibrillation (AF) patients. Patient-centered medical homes (PCMHs) may increase access, quality, and value through coordinating care. As such, PCMHs hold potential for improving OAT initiation among AF patients. We estimated the effect of receiving care in accredited PCMHs on OAT initiation for incident AF patients compared with those not receiving care in accredited PCMHs. Our study, a retrospective cohort new user design, included privately insured patients in North Carolina during years 2006 to 2010. We developed propensity scores for PCMH exposure, performed inverse probability of treatment weighting, and estimated effects with generalized estimating equations. We found a positive association between PCMH exposure and OAT initiation in unadjusted (6.78%; p < .001) and adjusted (6.25%; p < .001) models. Greater implementation and optimization of PCMH model principles may enhance this association, reducing AF-related stroke morbidity and mortality.

New oral anticoagulants in elderly patients with atrial fibrillation

The prevalence of atrial fibrillation increases with age, augmenting the risk of embolic stroke in elderly individuals. Clinical practice guidelines recommend the long-term use of oral anticoagulation in elderly patients with atrial fibrillation to reduce risk of stroke. Until recently, vitamin K antagonists (eg, warfarin) were the only oral anticoagulants available, but using warfarin in elderly patients can be challenging. Newer oral anticoagulants may offer specific benefits and increased convenience for elderly patients, because they have predictable pharmacologic profiles, a rapid onset of action, a wide therapeutic window, no requirement for routine coagulation monitoring, and fewer and better-defined food and drug interactions compared with warfarin. This review highlights the benefits and challenges of warfarin use in elderly patients with atrial fibrillation and discusses potential efficacy and safety benefits for newer oral agents in these patients. The potential for increased rates of major bleeding in the elderly, particularly those with numerous concomitant medications or renal impairment, also is discussed. Practical considerations for the use of long-term anticoagulation in elderly patients also are discussed.

Recent advances in antithrombotic therapy for stroke prevention in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac dysrhythmia and patients with AF have a higher risk for stroke than the general population. The prevalence of AF is increasing, which underscores the importance of understanding the therapeutic options available for stroke prevention in the primary care setting. This article examines evidence for the use of novel oral anticoagulant (OAC) therapy, including the direct thrombin inhibitor dabigatran and the activated factor X inhibitors rivaroxaban and apixaban for stroke prevention in patients with AF. Although warfarin therapy is the gold standard for prevention of stroke, its use is associated with significant challenges related to drug-drug and food-drug interactions. Warfarin use also requires frequent blood monitoring to maintain anticoagulation within a narrow therapeutic window. Overall, the novel OACs are as good as, or better than, warfarin therapy for stroke prevention in patients with AF, and they have a comparable or reduced risk of associated major bleeding. In addition, the novel OACs have fewer drug-drug and food-drug interactions and do not require continuous blood monitoring. Integration of the novel OACs into clinical practice offers patients with AF new treatment options, and as therapeutic use of the novel OACs increases, real-world experience will add to our understanding of the value of these agents.

Reasons for non-use of proven pharmacotherapeutic interventions: systematic review and framework development

RATIONALE, AIMS AND OBJECTIVES

The quality of patient care and safety is dependent on addressing both errors of commission (e.g. overuse of medications) and errors of omission (e.g. patients receiving too little care). Despite guidelines recommending the use of certain proven pharmacotherapeutic interventions, a large gap exists between the patients that have an indication for, and those that actually receive such interventions. To address how the rate of implementation of proven interventions can be improved is dependent on a comprehensive knowledge of the factors contributing to their underuse. The aim of the review is to create an evidence-based framework of reasons why eligible patients do not receive proven pharmacotherapeutic interventions.

METHODS

A systemic review of the published reasons for non-use based on the Cochrane methodology.

RESULTS

The systematic review identified 67 articles meeting the inclusion criteria. The reasons for non-use were extracted from the studies and a framework was created from the results.

CONCLUSIONS

The factors associated with lack of implementation of proven pharmacotherapeutic interventions are complex and heterogeneous but can be understood from the perspectives of clinicians, patients and health care delivery systems. Efforts to increase the utilization of proven interventions should focus on disease/intervention-specific programmes that take into account the identified modifiable clinician, patient and system factors.

Apixaban for stroke prevention in atrial fibrillation: a review of the clinical trial evidence

The objective of this review is to summarize data from the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) and Apixaban Versus Acetylsalicylic Acid to Prevent Stroke in Atrial Fibrillation Patients Who Have Failed or Are Unsuitable for Vitamin K Antagonist Treatment (AVERROES) trials of apixaban for stroke prevention in patients with atrial fibrillation (AF). The ARISTOTLE trial compared apixaban with warfarin in 18 201 patients with AF and ≥ 1 additional risk factor for stroke. The AVERROES trial compared apixaban with aspirin in 5599 patients with AF who were at increased risk of stroke and for whom vitamin K antagonists were unsuitable. In ARISTOTLE, apixaban reduced the risk of stroke or systemic embolism by 21% compared with warfarin (1.27% vs 1.60% per year; hazard ratio, 0.79; 95% confidence interval, 0.66-0.95). The reduction was significant and demonstrated the superiority of apixaban over warfarin for the primary outcome of preventing stroke or systemic embolism (P = 0.01 for superiority). Apixaban also reduced all-cause mortality by 11% (P = 0.047) and major bleeding by 31% (P < 0.001) compared with warfarin. The benefits of apixaban observed in ARISTOTLE are further supported by the results from AVERROES, which demonstrated a 55% reduction in the risk of stroke or systemic embolism compared with aspirin. Risk of major bleeding was not significantly different between apixaban and aspirin. Subgroup analyses in both trials demonstrated that the effects of apixaban are highly consistent across various patient subpopulations. Discontinuation of study medication was significantly lower with apixaban than with either warfarin in ARISTOTLE or aspirin in AVERROES. Apixaban is the first new oral anticoagulant that has been shown to be superior to warfarin in reducing stroke or systemic embolism, all-cause mortality, and major bleeding in patients with AF. Moreover, in patients with AF who are considered unsuitable for warfarin therapy, apixaban was more effective than aspirin for stroke prevention and had a similar rate of major bleeding.

Anticoagulation management in clinical practice: preventing stroke in patients with atrial fibrillation

Atrial fibrillation (AF) is a major and widely recognized risk factor for cardioembolic stroke. Prophylactic therapy for the prevention of stroke in patients with AF is often achieved through oral anticoagulation, specifically with warfarin, which has been used for this purpose for more than 50 years. Although warfarin therapy is effective when implemented appropriately, it is often underutilized and requires consistent monitoring to ensure both safety in avoiding bleeding and efficacy in preventing strokes. Because the burden of AF-related stroke continues to rise, healthcare professionals need to understand the strengths and limitations of current and emerging treatment options. This review outlines current practices for managing the risk of stroke with anticoagulation in patients with AF, and discusses how new oral anticoagulants may affect clinical practice.

Atrial fibrillation care: challenges in clinical practice and educational needs assessment

BACKGROUND

Current debates around the choice of management strategy for patients with atrial fibrillation (AF) combined with limited efficacy and frequent adverse effects of current pharmacotherapies cause uncertainty and confusion, challenging optimal care delivery to AF patients.

OBJECTIVES

To determine gaps in knowledge, skill, and competencies of Canadian physicians caring for patients with AF as well as underlying causes of these gaps.

METHODS

A mixed-method approach --consisting of qualitative (semistructured interviews) and quantitative data collection techniques (online survey) --was conducted. Findings were triangulated to ensure the reliability and trustworthiness of findings. The combined sample (n = 161) included 43 family physicians/general practitioners, 23 internal medicine specialists, 48 cardiologists, 28 emergency physicians, 14 neurologists, and 5 patients.

RESULTS

Gaps and barriers impeding optimal care were related to an unclear definition of AF, uncertainty of its pathophysiology, and knowledge gaps across the care continuum, including screening, diagnosis, and treatment. Clinical decision-making, individualized patient therapy, communication with patients and between professionals, and application of guidelines were found to be particularly challenging. These issues are discussed in the context of the newly revised Canadian Cardiovascular Society (CCS) AF Guidelines.

CONCLUSIONS

Educational gaps exist across the entire continuum of care. Results from this study, along with the 2011 CCS guidelines for AF management, provide direction for solutions through physician education and professional development.

The impact of new and emerging clinical data on treatment strategies for atrial fibrillation

INTRODUCTION

The Atrial Fibrillation (AF) Exchange Group, an international multidisciplinary group concerned with the management of AF, was convened to review recent advances in the field and the potential impact on treatment strategies.

METHODS

Issues discussed included epidemiology and the impact of the rising incidence of AF on health care systems, developments in pharmacological and surgical interventions in the management of arrhythmias and thromboprophylaxis, the potential to affect treatment strategies, and barriers to implementing them.

RESULTS

The incidence of AF and the associated burden on health care systems are increasing with aging populations, prevalence of comorbidities and more effective treatment of cardiovascular diseases. Advances in available medical treatments, in particular dronedarone and dabigatran, with other products in development, offer the possibility of changes in treatment paradigms and a greater emphasis on reducing hospitalizations and improvement in long-term outcomes instead of a symptom/safety-driven approach in which the priority is symptom suppression without provoking drug toxicity. Developments in catheter ablation techniques may mean that, in experienced centers, ablation may be offered as first-line treatment in selected patient populations. Barriers to optimal treatment include underdiagnosis, lack of recognition as a serious condition and as a risk factor for stroke, limited access to care, inadequate implementation of guidelines, and poor adherence to treatment.

CONCLUSIONS

The focus of the management of AF may be changing as a consequence of new treatments based on the outcome improvements they offer. However, the benefits will not be fully realized if guidelines and guidance are not observed in routine clinical practice.