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Presents a synopsis of the American College of Chest Physicians Consensus Conference on Antithrombotic Therapy's proposed guidelines in treating patients with thromboembolic diseases of the arterial and venous systems. Pathobiology of thrombosis; Antithrombotic agents; Monitoring oral anticoagulant therapy; Complications; Reversing the anticoagulant effect of warfarin; Clinical guidelines.

The author discusses the personalization of warfarin therapy as suggested by the Food and Drug Administration (FDA). Though the U.S. Department of Health and Human Services declared personalization of health care as a top priority, the author questions the value of genetic testing prior to starting therapy, stating that the close monitoring of warfarin's effects that is performed during that therapy in any event makes such testing superfluous.

Background: Although non-vitamin K antagonist oral anticoagulants (NOACs) do not require frequent laboratory monitoring, each compound requires dose adjustments on the basis of certain clinical criteria.Objectives: This study assessed the frequency of off-label NOAC doses among AF patients and the associations between off-label dose therapy and clinical outcomes in community practice.Methods: We evaluated 5,738 patients treated with a NOAC at 242 ORBIT-AF II (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation phase II) sites. NOAC doses were classified as either underdosed or overdosed, consistent with Food and Drug Administration labeling. Longitudinal outcomes (median follow-up: 0.99 years) included stroke or systemic embolism, myocardial infarction, major bleeding (International Society of Thrombosis and Haemostasis criteria), cause-specific hospitalization, and all-cause mortality.Results: Overall, 541 NOAC-treated patients (9.4%) were underdosed, 197 were overdosed (3.4%), and 5,000 were dosed according to U.S. labeling (87%). Compared with patients receiving the recommended dose, those who were receiving off-label doses were older (median: 79 and 80 years of age vs. 70 years of age, respectively; p < 0.0001), more likely female (48% and 67% vs. 40%, respectively; p < 0.0001), less likely to be treated by an electrophysiologist (18% and 19% vs. 27%, respectively; p < 0.0001), and had higher CHA2DS2-VASc scores (96% and 97% ≥2 vs. 86%, respectively; p < 0.0001) and higher ORBIT bleeding scores (25% and 31% >4 vs. 11%, respectively; p < 0.0001). After dose adjustment, NOAC overdosing was associated with increased all-cause mortality compared with recommended doses (adjusted hazard ratio: 1.91; 95% confidence interval [CI]: 1.02 to 3.60; p = 0.04). Underdosing was associated with increased cardiovascular hospitalization (adjusted hazard ratio: 1.26; 95% CI: 1.07 to 1.50; p = 0.007).Conclusions: A significant minority (almost 1 in 8) of U.S. patients in the community received NOAC doses inconsistent with labeling. NOAC over- and underdosing are associated with increased risk for adverse events. (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II [ORBIT-AF II]; NCT01701817). [ABSTRACT FROM AUTHOR]

Background: Home INR testing (patient self-testing) is feasible and effective for warfarin patients but little is known about real-world differences in outcomes for patients using PST versus laboratory-based INR monitoring., Objective: To compare the safety/efficacy of patient self-testing of real-world warfarin therapy versus office/lab-based monitoring of therapy., Design/setting/participants/exposure: A retrospective claims-based analysis of warfarin patients enrolled in the MarketScan® Commercial Claims and Encounters and Medicare databases between January 1, 2013, and March 30, 2020. Stratification was based on INR testing method: patient self-testing versus testing at physicians' offices/local laboratory. The probability of adverse events in each cohort was determined after adjusting for demographic and baseline clinical characteristics using a repeated measures analysis., Main Measures: Rates of all adverse events: deep venous thrombosis, pulmonary embolism, bleeding, and stroke. A secondary outcome of interest was emergency department visits., Key Results: A total of 37,837 patients were included in the analysis: 1592 patients in the patient self-testing group and 36,245 in the office-based therapy group. After adjusting for demographic and baseline clinical characteristics, patients in the office-based group had statistically significantly higher rates of all adverse events (incidence rate ratio [IRR]=2.07, 95% CI [1.82, 2.36]), and specific adverse events including thromboembolism (IRR=4.38, 95% CI [3.29, 5.84]), major bleed (IRR=1.45, 95% CI [1.28, 1.64]), and stroke (IRR=1.30, 95% CI [1.05, 1.61]) than patients in the patient self-testing group. Office-based patients also had a statistically significant higher rate of emergency department visits than patient self-testing patients (IRR = 1.65, 95% CI [1.47, 1.84])., Conclusions/relevance: This analysis of real-world claims data shows lower rates of stroke, thromboembolism, and major bleeding, as well as fewer emergency department visits, with patient self-testing compared to office-based/lab INR monitoring. Our finding that PST is safe and effective among current users suggests that more patients may benefit from its use., (© 2023. The Author(s).)

While oral anticoagulation is a cornerstone of stroke prevention therapy in atrial fibrillation (AF), few studies have evaluated comparative discontinuation rates in clinical practice. The objective of this study is to evaluate discontinuation rates among patients on warfarin and direct oral anticoagulants (DOACs) in clinical practice., Methods: The ORBIT-AF II Registry enrolled 10,005 total AF patients with a CHA 2 DS 2 VASc score of ≥2 on warfarin or DOACs from 235 clinical practices across the US from February 13, 2013 and July 12, 2017. Descriptive statistics and multivariable Cox regression modeling were used to describe baseline characteristics and predictors of discontinuation. Unadjusted and adjusted discontinuation rates and 95% confidence intervals (CI) were calculated using Cox proportional hazards models and propensity score adjustment, respectively., Results: At baseline, 16.4% (N = 1642/10,005) were treated with warfarin, 83.6% (N = 8363/10,005) with DOACs and 1498/10,005 patients (15.0%) discontinued therapy [warfarin = 236/1642 (14.4%) vs DOACs = 1262/8363 (15.1%)]. At 6 and 12 months respectively, among 7049 patients with a new diagnosis of AF within 6 months, adjusted discontinuation rates for warfarin versus DOACs were as follows: [6 months: 7.9%, 95%CI (6.8%-9.0%) vs 9.6% (8.4%-10.7%), P = .16]; [12 months: 12.7% (11.0%-14.3%) vs 15.3% (13.6%-16.9%), P = .02)]. Patients who discontinued therapy with warfarin or DOACs had higher risk of adverse clinical outcomes including: all-cause mortality and cardiovascular death (CV) than those who continued treatment., Conclusion: In a community based AF cohort, adjusted rates of discontinuation at 12-months were higher in DOAC-treated versus VKA-treated patients. Discontinuation of oral anticoagulation was associated with increased absolute risk of all-cause mortality and CV death., Clinical Trial Registration: URL:https://clinicaltrials.gov. Unique Identifier: NCT01701817., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Patients with atrial fibrillation on oral anticoagulation (OAC) undergoing cardiac catheterization face risks for embolic and bleeding events, yet information on strategies to mitigate these risks in contemporary practice is lacking., Methods: We aimed to describe the clinical/procedural characteristics of a contemporary cohort of patients with atrial fibrillation on OAC who underwent cardiac catheterization. Use of bleeding avoidance strategies and bridging therapy were described and outcomes including death, stroke, and major bleeding at 30 days and 1 year were compared by OAC type., Results: Of 13 404 patients in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II Registry from 2013 to 2016, 741 underwent cardiac catheterization (139 with percutaneous coronary intervention) in the setting of OAC. The patients' median age was 71, 61.8% were male, white (87.2%), had hypertension (83.7%), hyperlipidemia (72.1%), diabetes mellitus (31.6%), and chronic kidney disease (28.2%); 20.2% received warfarin while 79.8% received direct acting oral anticoagulant. One third of patients underwent radial artery access, and bivalirudin was used in 4.6%. Bridging therapy was used more often in patients on warfarin versus direct acting oral anticoagulant (16.7% versus10.0%). OAC was interrupted in 93.8% of patients. Patients on warfarin versus direct acting oral anticoagulant were equally likely to restart OAC (58.0% versus 60.7%), had similar use of antiplatelet therapy (44.0% versus 41.3%) after catheterization, and had similar rates of myocardial infarction and death at 1 year, but higher rates of major bleeding (43.3 versus 12.9 events/100 patient years) and stroke (4.9 versus 1.9 events/100 patient years)., Conclusions: In a real-world registry of patients with atrial fibrillation undergoing cardiac catheterization, most cases are elective, performed by femoral access, with interruption of OAC. Bleeding avoidance strategies such as radial artery access and bivalirudin were used infrequently and use of bridging therapy was uncommon. Nearly 40% of patients did not restart OAC postprocedure, exposing patients to risk for stroke. Further research is necessary to optimize the management of patients with atrial fibrillation undergoing cardiac catheterization.

Competing Interests: Conflicts of Interest All authors report no conflicts of interest.

Background: Renal function has been associated with an increased stroke risk in patients with atrial fibrillation (AF). However, whether renal function incrementally adds to risk prediction in both anticoagulated and non-anticoagulated patients with AF is unclear., Methods: We used data from the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF)-a national, prospective, outpatient AF registry in patients aged >18 years (2010-2011). The association between baseline renal function and risk of stroke/systemic embolism (SSE) was evaluated in proportional hazards models adjusting for stroke risk score components. We compared discrimination of 2-year outcomes using C-indices and evaluated calibration by comparing event rates in ORBIT-AF to published rates from an external clinical trial population (ROCKET AF) and an observational cohort (ATRIA)., Results: Among 9743 patients included in the analysis, the median age was 75 years (interquartile range [IQR] 67-82), 89.5% were white, 43% were female, and 76% were taking oral anticoagulation (OAC). Over a median follow-up of 2.3 years, 214 SSE events occurred (1.00 per 100 patient-years). Continuous creatinine clearance (CrCl) was not associated with SSE risk after adjusting for other clinical factors (components of CHADS 2 or CHA 2 DS 2 -VASc). Discrimination for predicting stroke (C-index; 95% CI) was similar for R 2 CHADS 2 (0.65; 0.61-0.69), CHADS 2 (0.65; 0.61-0.69), and CHA 2 DS 2 -VASc (0.66; 0.62-0.70)., Conclusions and Relevance: In a community patient population with AF, renal dysfunction was not independently associated with embolic risk beyond other established risk factors in either OAC-treated or untreated patients. Additional study is needed to identify clinical factors that incrementally add to stroke risk prediction., (Copyright © 2018. Published by Elsevier B.V.)

Background: Anticoagulated patients are particularly vulnerable to ADEs when they experience changes in medical acuity, pharmacotherapy, or care setting, and resources guiding care transitions are lacking. The New York State Anticoagulation Coalition convened a task force to develop a consensus list of requisite data elements (RDEs) that should accompany all anticoagulated patients undergoing care transitions., Methods: A multidisciplinary panel of 15 anticoagulation experts voluntarily completed an iterative Delphi process. Resources were disseminated and deliberated via remote technology, with consensus achieved via blinded electronic polling., Results: The panel reached consensus on a list of 15 RDEs for anticoagulation communication at discharge (the ACDC List). Consensus was rapidly achieved by the full panel on 13 elements, while 3 (2 of which were combined into 1 element) required multiple iterations and achieved consensus with votes from 8 available panelists. The elements encompassed a range of factors, including drug use and indications, previous exposure and duration of therapy, recent drug exposure and laboratory results and expectations for subsequent administration, therapy goals, patient education and comprehension, and expectations for clinical management. Twelve of the elements are applicable to any anticoagulant, and 3 are specific to warfarin., Conclusion: The ACDC List identifies specific pieces of clinical information that a panel of anticoagulant experts agree should be communicated to downstream providers for all anticoagulated patients undergoing care transitions. Additional study is needed to objectively evaluate the ability of existing care systems to communicate the elements and to assess possible relationships between communication of the elements and clinical outcomes., (Copyright © 2018 The Joint Commission. All rights reserved.)

Background: Bleeding is commonly cited as a reason for stopping oral anticoagulants (OACs). Whether minor bleeding events (nuisance bleeding, NB) in patients with atrial fibrillation on OACs are associated with OAC discontinuation, major bleeding, and stroke/systemic embolism (SSE) is unknown., Methods: Within the ORBIT-AF prospective, outpatient registry (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation), we identified 6771 patients ≥18 years of age at 172 sites with atrial fibrillation and eligible follow-up visits. NB was ascertained from the medical record and was defined as minor bleeding that did not require medical attention (eg, bruising, hemorrhoidal bleeding). We used multivariable pooled logistic regression modeling to evaluate the associations between NB and major bleeding and SSE in the 180 days after documentation of NB. Our unit of analysis was the patient visit, occurring at ≈6-month intervals for a median of 1.5 years following enrollment. Changes in anticoagulation treatment satisfaction after NB were examined descriptively in a subset of patients., Results: The median age of the overall population was 75.0 (interquartile range, 67.0-81.0); 90.0% were white and 42.5% were female. Among 6771 patients (18 560 visits), n=1357 (20.0%) had documented NB, for an incidence rate of 14.8 events per 100 person-years. Over 96.4% of patients remained on OAC therapy after the NB event. Overall, 287 (4.3%) patients experienced major bleeding and 64 (0.96%) had a SSE event during follow-up. NB was not associated with a significant increased risk of major bleeding over 6 months in models adjusting for the ATRIA bleeding score (Anticoagulation and Risk Factors in Atrial Fibrillation) (odds ratio, 1.04; 95% confidence interval, 0.68-1.60; P=0.86). NB was also not associated with increased SSE risk over 6 months in models adjusting for the CHA 2 DS 2 -VASc risk score (odds ratio, 1.24; 95% confidence interval, 0.53-2.91; P=0.62)., Conclusions: NB is common among patients with atrial fibrillation on OACs. However, NB was not associated with a higher risk of major bleeding or SSE over the next 6 months, suggesting its occurrence should not lead to changes in anticoagulation treatment strategies in OAC-treated patients., Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01165710.

Background: Non-vitamin K antagonist oral anticoagulants (NOACs) are indicated for stroke prevention in atrial fibrillation (AF) but require lower doses in certain patients. We sought to describe the frequency, appropriateness (according to Food and Drug Administration labeling), and outcomes of patients prescribed reduced doses of NOACs in community practice., Methods and Results: We analyzed data from the ORBIT-AF II (The Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II) registry, a prospective, national, observational registry of AF patients. Among 7925 AF patients receiving NOACs, we assessed patterns of use of reduced NOAC doses and associated cardiovascular and bleeding outcomes at median follow-up of 1 year. Overall, 6636 patients (84%) received a NOAC at standard dose, which was consistent with US Food and Drug Administration labeling in 6376 (96%). Reduced NOAC dose was prescribed to 1289 (16% overall), which was consistent with Food and Drug Administration labeling in only 555 patients (43%). Compared with those whose NOAC dose was appropriately reduced, patients receiving inappropriate dose reductions were younger (median age 79 versus 84, P <0.0001) and had lower ORBIT bleeding risk scores (26% ≥4 versus 45%, P <0.0001). Compared with those appropriately receiving standard dosing, patients receiving inappropriately reduced-dose NOACs had higher unadjusted rates of thromboembolic events (2.11 versus 1.35 events per 100 patient years, hazard ratio 1.56, 95% confidence interval 0.92-2.67) and death (6.77 versus 2.60, hazard ratio 2.61, 95% confidence interval 1.86-3.67). After adjustment, outcomes were not significantly different but tended to favor patients dosed appropriately., Conclusions: The majority of dose reductions of NOACs in AF are inconsistent with US Food and Drug Administration recommendations. There appear to be opportunities to improve current NOAC dosing in community practice., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01701817., (© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: The presence of valvular heart disease (VHD) may affect the risk of stroke and mortality in patients with atrial fibrillation (AF). Community-based estimates of prevalence and outcomes of specific forms of VHD in patients with AF are lacking., Methods and Results: We examined the prevalence of VHD, anticoagulation use, mortality, stroke/transient ischemic attack, and bleeding among a community cohort of patients with AF. Significant VHD was defined as follows: (1) moderate/severe mitral stenosis or mechanical valve; (2) bioprosthetic valve, surgical repair, or balloon valvuloplasty; and (3) moderate/severe aortic regurgitation or stenosis, mitral regurgitation, or tricuspid regurgitation. Proportional hazards models were performed to test the association between VHD groups and outcomes. Among 9748 patients with AF, 2705 (27.7%) had significant VHD. Anticoagulation use was highest among patients with mitral stenosis/mechanical valve (91.8%). Compared with individuals with no significant VHD, individuals with aortic regurgitation/aortic stenosis, mitral regurgitation, or tricuspid regurgitation (hazard ratio, 1.23; 95% confidence interval, 1.07-1.42) had the highest risk of death. There were no differences in stroke or transient ischemic attack and major bleeding among individuals with and without significant VHD. Patients with AF and aortic stenosis had the highest risk of death (hazard ratio, 1.32; 95% confidence interval, 1.08-1.62)., Conclusions: Significant VHD is common among patients with AF in community practice. In a community cohort of patients with AF and CHA 2 DS 2 -VASc score ≥2, most were anticoagulated. Individuals with AF and moderate-to-severe biological VHD have more comorbidities and a higher mortality risk; however, stroke and major bleeding are similar among those with and without significant VHD., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: It is unclear how frequently patients with atrial fibrillation receive guideline-concordant (GC) care and whether guideline concordance is associated with improved outcomes., Methods and Results: Using data from ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation), we determined how frequently patients received care that was concordant with 11 recommendations from the 2014 American Heart Association/American College of Cardiology/Heart Rhythm Society atrial fibrillation guidelines pertaining to antithrombotic therapy, rate control, and antiarrhythmic medications. We also analyzed the association between GC care and clinical outcomes at both the patient level and center level. A total of 9570 patients were included. The median age was 75 years (interquartile range, 67-82), and the median CHA 2 DS 2 -VASc score was 4 (interquartile range, 3-5). A total of 5977 patients (62.5%) received care that was concordant with all guideline recommendations for which they were eligible. Rates of GC care were higher in patients treated by providers with greater specialization in arrhythmias (60.0%, 62.4%, and 67.0% for primary care physicians, cardiologists, and electrophysiologists, respectively; P <0.001). During a median of 30 months of follow-up, patients treated with GC care had a higher risk of bleeding hospitalization (hazard ratio=1.21; P =0.021) but a similar risk of death, stroke, major bleeding, and all-cause hospitalization., Conclusions: Over a third of patients with atrial fibrillation in this large outpatient registry received care that differed in some respect from guideline recommendations. There was no apparent association between GC care and improved risk-adjusted outcomes., (© 2017 American Heart Association, Inc.)

Importance: The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial reported that apixaban therapy was superior to warfarin therapy in preventing stroke and all-cause death while causing significantly fewer major bleeds. To establish the value proposition of substituting apixiban therapy for warfarin therapy in patients with atrial fibrillation, we performed a cost-effectiveness analysis using patient-level data from the ARISTOTLE trial., Objective: To assess the cost and cost-effectiveness of apixaban therapy compared with warfarin therapy in patients with atrial fibrillation from the perspective of the US health care system., Design, Setting, and Participants: This economic analysis uses patient-level resource use and clinical data collected in the ARISTOTLE trial, a multinational randomized clinical trial that observed 18 201 patients (3417 US patients) for a median of 1.8 years between 2006 and 2011., Interventions: Apixaban therapy vs warfarin therapy., Main Outcomes and Measures: Within-trial resource use and cost were compared between treatments, using externally derived US cost weights. Life expectancies for US patients were estimated according to their baseline risk and treatment using time-based and age-based survival models developed using the overall ARISTOTLE population. Quality-of-life adjustment factors were obtained from external sources. Cost-effectiveness (incremental cost per quality-adjusted life-year gained) was evaluated from a US perspective, and extensive sensitivity analyses were performed., Results: Of the 3417 US patients enrolled in ARISTOTLE, the mean (SD) age was 71 (10) years; 2329 (68.2%) were male and 3264 (95.5%) were white. After 2 years of anticoagulation therapy, health care costs (excluding the study drug) of patients treated with apixaban therapy and warfarin therapy were not statistically different (difference, -$60; 95% CI, -$2728 to $2608). Life expectancy, modeled from ARISTOTLE outcomes, was significantly longer with apixaban therapy vs warfarin therapy (7.94 vs 7.54 quality-adjusted life years). The incremental cost, including cost of anticoagulant and monitoring, of achieving these benefits was within accepted US norms ($53 925 per quality-adjusted life year, with 98% likelihood of meeting a $100 000 willingness-to-pay threshold). Results were generally consistent when model assumptions were varied, with lifetime cost-effectiveness most affected by the price of apixaban and the time horizon., Conclusions and Relevance: Apixaban therapy for ARISTOTLE-eligible patients with atrial fibrillation provides clinical benefits at an incremental cost that represents reasonable value for money judged using US benchmarks for cost-effectiveness., Trial Registration: clinicaltrials.gov Identifier: NCT00412984.

Anticoagulation with warfarin requires frequent evaluation of the international normalized ratio (INR), and less invasive testing devices are available for use by clinicians at the point-of-care (POC) and by patients who self-test (PST). Despite commercial availability and positive results of published studies, evidence suggests that adoption of less invasive (POC/PST) testing in the United States is slow. Considering the equivalence of results and logistical advantages of POC/PST testing, slow uptake may indicate a gap in quality of care warranting evaluation and possibly intervention. This study used Medicare fee for service claims data to explore the uptake of POC/PST INR monitoring across New York State over a 6 year time frame (2006-11), with additional analyses based on beneficiary age, sex, race and ethnicity and income by county. In 2006, only 28.3% of 103,410 analyzable beneficiaries presumed to be chronic warfarin users based on INR testing patterns were monitored by POC/PST, and increased to only 37.6% by 2011. Utilization of POC/PST testing varied widely by county (baseline range 1.2-89.4%), and uptake of these testing modalities in New York State was significantly lower among the very elderly, women, and ethnic minorities. We hypothesize that poor penetration of these less invasive INR testing modalities into highly populated New York City and barriers to POC utilization in long term care facilities may account for a portion of the variability in INR testing patterns observed in this study. However, additional research is needed to further explore whether disparities in warfarin monitoring practices exist.

Background: Time in therapeutic range (TTR) of international normalized ratio (INR) of 2.0 to 3.0 is important for the safety and effectiveness of warfarin anticoagulation. There are few data on TTR among patients with atrial fibrillation (AF) in community-based clinical practice., Methods: Using the US Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF), we examined TTR (using a modified Rosendaal method) among 5,210 patients with AF on warfarin and treated at 155 sites. Patients were grouped into quartiles based on TTR data. Multivariable logistic regression modeling with generalized estimating equations was used to determine patient and provider factors associated with the lowest (worst) TTR., Results: Overall, 59% of the measured INR values were between 2.0 and 3.0, with an overall mean and median TTR of 65% ± 20% and 68% (interquartile range [IQR] 53%-79%). The median times below and above the therapeutic range were 17% (IQR 8%-29%) and 10% (IQR 3%-19%), respectively. Patients with renal dysfunction, advanced heart failure, frailty, prior valve surgery, and higher risk for bleeding (ATRIA score) or stroke (CHA2DS2-VASc score) had significantly lower TTR (P < .0001 for all). Patients treated at anticoagulation clinics had only slightly higher median TTR (69%) than those not (66%) (P < .0001)., Conclusions: Among patients with AF in US clinical practices, TTR on warfarin is suboptimal, and those at highest predicted risks for stroke and bleeding were least likely to be in therapeutic range., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Atrial fibrillation (AF) is the most common cardiac dysrhythmia and contributes significantly to health care expenditures. We sought to assess the frequency and predictors of hospitalization in patients with AF., Methods: The ORBIT-AF registry is a prospective, observational study of outpatients with AF enrolled from June 29, 2010, to August 9, 2011. The current analysis included 9,484 participants with 1-year follow-up. Multivariable, logistic regression was used to identify baseline characteristics that were associated with first cause-specific hospitalization., Results: Overall, 31% of patients with AF studied (n = 2,963) had 1 or more hospitalizations per year and 10% (n = 983) had 2 or more. The most common hospitalization cause was cardiovascular (20 per 100 patient-years vs 3.3 bleeding vs 17 noncardiovascular, nonbleeding). Compared with those not hospitalized, hospitalized patients were more likely to have concomitant heart failure (42% vs 28%, P < .0001), higher mean CHADS2 (1 point for congestive heart failure, hypertension, age ≥75, or diabetes; 2 points for prior stroke or transient ischemic attack) scores (2.5 vs 2.2, P < .0001), and more symptoms (baseline European Heart Rhythm Association class severe symptoms 18% vs 13%, P < .0001). In multivariable analysis, heart failure (adjusted hazard ratio [HR] 1.57 for New York Heart Association III/IV vs none, P < .0001), heart rate at baseline (adjusted HR 1.11 per 10-beats/min increase >66, P < .0001), and AF symptom class (adjusted HR 1.37 for European Heart Rhythm Association severe vs none, P < .0001) were the major predictors of incident hospitalization., Conclusions: Hospitalization is common in outpatients with AF and is independently predicted by heart failure and AF symptoms. Improved symptom control, rate control, and comorbid condition management should be evaluated as strategies to reduce health care use in these patients., (Copyright © 2014 Mosby, Inc. All rights reserved.)

Background: Anticoagulation control with warfarin, as assessed by the international normalized ratio (INR), is challenging. Time in the therapeutic range has been inversely correlated with major hemorrhage, thrombosis, and mortality. Quest Diagnostics offers standardized INR laboratory testing services to approximately half of US physician practices. To inform national stroke prevention strategies, we evaluated anticoagulation control in office-based community practices., Methods and Results: We selected individuals with ≥2 months of INR data, INR results of >1.2, and an ICD-9 diagnosis code of atrial fibrillation. Frequency of INR testing and time in the therapeutic range were analyzed by age, sex, length of testing period, number of referred patients per provider, and median household income (based on home ZIP code). We identified 138 319 individuals referred by 37 939 physicians, yielding a total of 2 683 674 INR results. Patients had a mean age of 74 years; 81% were ≥65 years of age, and 55% were ≥75 years of age. The mean time in the therapeutic range was 53.7% overall and improved with time on treatment, increasing from 47.6% for patients with <6 months of testing to 57.5% for those with ≥6 months of testing (P<0.0001). The number of patients tested per physician practice was positively associated with time in the therapeutic range. Younger age, female sex, and lower income were also independently associated with poorer anticoagulant control., Conclusion: This study demonstrates widespread suboptimal anticoagulation control, suggesting an urgent need to improve oral anticoagulation care for most patient segments in the United States.

Objectives: Point-of-care, home international normalized ratio (INR) monitoring (patient self-testing, or PST) provides an opportunity to optimize warfarin therapy as demonstrated in randomized trials. This study sought to determine the quality of warfarin therapy as determined by time in therapeutic INR range (TTR) in patients who perform home monitoring outside of a clinical trial setting., Study Design: Retrospective analysis., Methods: The data base of an independent diagnostic testing facility was retrospectively queried over a 2.5-year period (January 2008-June 2011) and patient TTR was analyzed based on frequency of testing, age, gender, indication for therapy, duration of therapy, and critical value occurrence., Results: A total of 29,457 patients with multiple indications for warfarin therapy comprised the database. The mean TTR for the entire group was 69.7%, with weekly testers achieving a TTR of 74% versus 68.9% for variable testers (testing every 2-4 weeks)(P <.0001). In all categories analyzed (age, indication for anticoagulation, and referral site volume), weekly testers performed significantly better than variable testers. Older individuals had a higher TTR than younger patients. Weekly testers experienced significantly fewer critical values (INR <1.5 or >5.0) than did variable testers., Conclusions: Point-of-care patient self-testing at home achieves high-quality warfarin therapy outside of clinical trials and compares favorably with the results achieved in randomized trials or in anticoagulation clinic settings.

Background: Dabigatran is a novel oral anticoagulant approved for thromboprophylaxis in atrial fibrillation. Adoption patterns of this new agent in community practice are unknown., Methods and Results: We studied patterns of dabigatran use among patients enrolled in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) Registry between June 2010 and August 2011 and followed for 12 months. Among 9974 atrial fibrillation patients included, 1217 (12%) were treated with dabigatran during the study. Overall, patients receiving dabigatran were younger (median age 72 versus 75 years, P<0.0001), more likely to be white (92% versus 89%, P=0.005), more likely to have private insurance (33% versus 25%, P<0.0001), and less likely to have prior cardiovascular disease (4% versus 33%, P<0.0001). They had more new-onset atrial fibrillation (8.8% versus 4.1%, P<0.0001), lower CHADS2 scores (estimated risk based on the presence of congestive heart failure, hypertension, aged ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack; mean 2.0 versus 2.3, P<0.0001), and lower Anticoagulation and Risk Factors in Atrial Fibrillation scores (mean 2.4 versus 2.8, P<0.0001). More than half (n=14/25, 56%) of patients with severe kidney disease were not prescribed reduced dosing, whereas 10% (n=91/920) with preserved renal function received lower dosing. Among patients not on dabigatran at baseline, 8% had dabigatran initiated during follow-up. Patient education was significantly associated with switching from warfarin to dabigatran (adjusted odds ratio for postgraduate 1.73, P=0.007), whereas antiarrhythmic drug use significantly correlated with de novo adoption of dabigatran (adjusted odds ratio 2.4, P<0.0001)., Conclusions: Patients receiving dabigatran were younger and at a lower risk of stroke and bleeding. Patients appeared to drive switching from warfarin, whereas clinical characteristics influenced de novo start of dabigatran. These data suggest cautious early uptake of dabigatran, and more careful attention to dosing adjustments is warranted., Clinical Trial Registration Url: Clinicaltrials.gov. Unique identifier: NCT01165710.

Background: Patients with atrial fibrillation (AF) at the highest stroke risk derive the largest benefit from oral anticoagulation (OAC). Those with the highest stroke risk have been paradoxically less likely to receive OAC. This study assessed the association between stroke and bleeding risk on rates of OAC., Methods and Results: We analyzed OAC use among 10,098 patients with AF from 174 community-based outpatient practices enrolled in 2010-2011 in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). OAC was defined as warfarin or dabigatran use at study enrollment. Stroke and bleeding risk were calculated using congestive heart failure, hypertension, age, diabetes mellitus, prior stroke (CHADS₂), and anticoagulation and risk factors in AF (ATRIA) scores, respectively. The mean subject age was 73 years; 58% were men. Overall, 76% of patients received OAC (71% warfarin and 5% dabigatran). The use of OAC increased among those with higher CHADS₂ scores, from 53% for CHADS₂=0 to 80% for CHADS₂≥2 (P<0.001). OAC use fell slightly with increasing ATRIA bleeding risk score, from 81% for ATRIA=3 to 73% for ATRIA≥5 (P<0.001). A significant interaction existed between ATRIA and CHADS₂ scores (P=0.021). Among those with low bleeding risk, use of OAC increased significantly with increasing stroke risk. Among those with high bleeding risk, CHADS₂ stroke risk had a smaller impact on use of OAC., Conclusions: In community-based outpatients with AF, use of OAC was high and driven by not only predominantly stroke but also bleeding risk. Stroke risk significantly affects OAC use among those with low bleeding risk, whereas those with high bleeding risk demonstrate consistently lower use of OAC regardless of stroke risk.

Successful therapy with vitamin K antagonists requires maintaining a patient in the therapeutic international normalized ratio (INR) range for the particular indication under treatment. Achieving this is dependent on the model of dose management under which the therapy is provided. Most patients in the United States are managed by their individual physician and the time in therapeutic range (TTR) is often low. Patients who have monitored their therapy at home with a point-of-care INR monitor have demonstrated an ability to achieve a high rate of TTR as documented in clinical trials. Recently, similar or even better rates of TTR have been demonstrated in patients performing home monitoring outside of a clinical trial. These findings support the recommendations to implement home monitoring in those who have demonstrated competency in self-management strategies.

Objective: Anticoagulation quality and record documentation were retrospectively assessed in patients with chronic nonvalvular atrial fibrillation (CNVAF) managed in a routine care setting., Methods: Medical record data extraction from physician practices in 4 regions of the United States., Results: Of 686 patients, 59% had an electrocardiogram confirming CNVAF, 84% listed at least 1 stroke risk factor, and 60% indicated the goal target international normalized ratio (INR). Two thirds of INRs>3.0 or <2.0 had no recorded dose change, nor did 45% of INRs>5.0. Vitamin K was given (3%) or anticoagulation was temporarily discontinued (9%) for INRs>5.0. The median interval of INR testing was 21 days, which decreased to 7 days for INRs> 4.60. Patients spent 58% of the time in therapeutic range., Conclusion: Serious deficiencies in quality and documentation of routine medical care of anticoagulation for patients with CNVAF continue to exist.

Background/objectives: Expert oral anticoagulation management is the key to good outcomes and is performed variably in different health care systems throughout the world. We set out to assess the quality of anticoagulation management in five countries in patients receiving vitamin K antagonists (VKAs) for stroke prophylaxis in chronic non-valvular atrial fibrillation (NVAF), and to compare the anticoagulation management practices in these countries., Methods and Results: This was a retrospective, multi-centre cohort study in the United States, Canada, France, Italy, and Spain. About 1,511 patients were randomly recruited from representative practices (routine medical care (RMC) in the US, Canada, and France; anticoagulation clinics in Italy and Spain) and data pertaining to their oral anticoagulation care were abstracted from their medical records. The predominant anticoagulant in use was warfarin in the US, Canada, and Italy; acenocoumarol in Spain; and fluindione in France. Documentation of care was poor in the US, Canada, and France, countries where RMC was studied. Percent INRs or time-in-therapeutic range was greater in the two anticoagulation clinic samples compared with the RMC samples., Conclusion: Oral anticoagulation care varies considerably from country to country. Findings suggest that anticoagulation clinic care (ACC) may provide better outcomes as assessed by international normalized ratio (INR) time-in-range. Physicians tend to under treat more than over treat. Finally, documentation of care is often inadequate. Condensed Abstract Oral anticoagulation management (routine medical care or anticoagulation clinic care) was retrospectively assessed in 5 countries using a uniform, structured assessment tool. Major management differences were detected, especially between anticoagulation clinic care and routine care. Documentation was often a problem in the latter setting. Less time in therapeutic INR range was noted in routine medical care. Findings suggest that anticoagulation clinic care may provide better outcomes as assessed by international normalized ratio (INR) time-in-range. Physicians tend to under treat more than over treat. Finally, documentation of care is often inadequate.

Oral anticoagulation with warfarin requires routine monitoring of prothrombin time, expressed as the international normalized ratio (INR). Patient self-testing for INR is common in Europe but not in the United States. In order to determine the frequency of INR self-testing among patients whose anticoagulant therapy is managed in U.S. anticoagulation clinics, to describe the processes that support this self-testing, and to identify the barriers as experienced by anticoagulation clinic providers, a three-part survey was mailed to 538 anticoagulation specialists in the United States. The response rate was 43.7%. Policies and procedures of almost 60% of anticoagulation clinics prohibited INR self-testing for enrolled patients. In addition, less than 1% of patients being managed by U.S. anticoagulation clinics use self-testing to obtain INR results. Primary barriers were the cost of self-testing instruments (78.7% of respondents), cost of reagent cartridges (60.4%), and fear that self-testing might lead to unintended self-management (35.7%). Over 75% of respondents believed that some reimbursement for the cost of self-testing devices and supplies would increase the likelihood that anticoagulation clinics would recommend INR self-testing.

Objectives: To characterize the services and activities performed by anticoagulation clinics (ACCs) across the United States, examine the anticipated impact that oral direct thrombin inhibitors (DTIs) will have on the clinical services of ACCs, and elicit possible management strategies to realign services provided by ACCs and opportunities for restructuring clinical services., Methods: A survey was developed in consultation with content experts in the field, pretested by several ACC providers, and subsequently refined. Surveys were mailed to 400 randomly selected ACC-based providers., Results: The final usable response rate was 34.5% (115 of 333 surveys). Respondents anticipated that the number of patient visits/month would decrease from a median of 336 (interquartile range [IQR] 151-775) to 150 (IQR 71-350, p<0.001) after the introduction of oral DTIs. In addition, time spent on many direct and indirect patient care activities currently performed by ACCs was expected to decline. Respondents indicated that ACCs may find new roles by providing guidance on individual suitability for therapy, managing the transition to oral DTIs, providing education for patients and health care providers on thrombotic disease state management, monitoring patients for recurrent thrombosis and risk of bleeding complications, monitoring patient compliance, and providing counseling and safety surveillance for patients receiving treatment with oral DTIs., Conclusion: The advent of oral DTIs is likely to have a significant impact on the structure and delivery of antithrombotic services. Clinics that are proactive and redesign their patient care services to consider emerging anticoagulant agents will be more likely to remain relevant and viable.