Residual stroke risk despite oral anticoagulation in patients with atrial fibrillation.

Background: Oral anticoagulation (OAC) reduces the risk of thromboembolic events in patients with atrial fibrillation (AF); however, thromboembolism (TE) still can occur despite OAC. Factors associated with residual risk for stroke, systemic embolism, or transient ischemic attack events despite OAC have not been well described. Objective: The purpose of this study was to evaluate the residual risk of thromboembolic events in patients with AF despite OAC. Methods: A total of 18,955 patients were analyzed in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF I and II) using multivariable Cox proportional hazard modeling. Mean age was 72 ± 10.7, and 42% were women. There were 451 outcome events. Results: The risk of TE despite OAC increased with CHA2DS2-VASc score: 0.76 (95% confidence interval [CI] 0.63-0.92) events per 100 patient-years for CHA2DS2-VASc score <4 vs 2.01 (95% CI 1.81-2.24) events per 100-patient years for CHA2DS2-VASc score >4. Factors associated with increased risk were previous stroke or transient ischemic attack (hazard ratio [HR] 2.87; 95% CI 2.30-3.59; P <.001), female sex (HR 1.52; 95% CI 1.24-1.86; P <.001), hypertension (HR 1.50; 95% CI 1.09-2.06; P = .01), and permanent AF (HR 1.47; 95% CI 1.12-1.94; P = .001). When transient ischemic attack was excluded, the results were similar, but permanent AF was no longer significantly associated with thromboembolic events. Conclusion: Patients with AF have a residual risk of TE with increasing CHA2DS2-VASc score despite OAC. Key risk markers include previous stroke/transient ischemic attack, female sex, hypertension, and permanent AF.

Decline in renal function and oral anticoagulation dose reduction among patients with atrial fibrillation.

OBJECTIVE: Non-vitamin K oral anticoagulants (NOACs) require dose adjustment for renal function. We sought to investigate change in renal function over time in patients with atrial fibrillation (AF) and whether those on NOACs have appropriate dose adjustments according to its decline. METHODS: We included patients with AF enrolled in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II registry treated with oral anticoagulation. Worsening renal function (WRF) was defined as a decrease of >20% in creatinine clearance (CrCl) from baseline. The US Food and Drug Administration (FDA)-approved package inserts were used to define the reduction criteria of NOACs dosing. RESULTS: Among 6682 patients with AF from 220 sites (median age (25th, 75th): 72.0 years (65.0, 79.0); 57.1% male; median CrCl at baseline: 80.1 mL/min (57.4, 108.5)), 1543 patients (23.1%) experienced WRF with mean decline in CrCl during 2 year follow-up of -6.63 mL/min for NOACs and -6.16 mL/min for warfarin. Among 4120 patients on NOACs, 154 (3.7%) patients had a CrCl decline sufficient to warrant FDA-recommended dose reductions. Of these, NOACs dosing was appropriately reduced in only 31 (20.1%) patients. Compared with patients with appropriately reduced NOACs, those without were more likely to experience bleeding complications (major bleeding: 1.7% vs 0%; bleeding hospitalisation: 2.6% vs 0%) at 1 year. CONCLUSIONS: In the US practice, about one-fourth of patients with AF had >20% decline in CrCl over time during 2 year follow-up. As a result, about 3.7% of those treated with NOACs met guideline criteria for dose reduction, but of these, only 20.1% actually had a reduction.

Treatment of atrial fibrillation with concomitant coronary or peripheral artery disease: Results from the outcomes registry for better informed treatment of atrial fibrillation II.

BACKGROUND: Treatment patterns and outcomes of individuals with vascular disease who have new-onset atrial fibrillation (AF) are not well characterized. METHODS: Among patients with new-onset AF, we analyzed treatment and outcomes in those with or without vascular disease in the ORBIT-AF II registry. Vascular disease was defined as coronary disease with or without myocardial infarction (MI) or revascularization, or peripheral artery disease. The primary outcomes included major adverse cardiovascular or neurological events (MACNE) and major bleeding. Cox proportional hazard models were used to adjust the difference in patient characteristics. RESULTS: Overall 1920 of 6203 (31.0%) of new-onset AF had vascular disease. In patients with vascular disease, 62.2% of those were treated with direct oral anticoagulants (DOACs) and 23.4% with warfarin. Dual therapy and triple therapy were used in 36.9% and 4.9%, respectively. Vascular disease patients had increased risk of MACNE (adjusted hazard ratio [aHR] 1.83 [95%CIs 1.32-2.55]), but not major bleeding (aHR 1.24 [0.95-1.63]). Among patients with vascular disease, relative to those on warfarin, those treated with DOACs had similar risk for MACNE (aHR 1.20 [0.77-1.87]) but lower risks for bleeding, although it did not reach statistical significance (aHR 0.70 [0.43-1.15]). Concomitant antiplatelet therapy was associated with higher bleeding (aHR 2.27 [1.38-3.73]) with no apparent reduction in MACNE (aHR 1.50 [1.00-2.25]). CONCLUSIONS: Most patients with AF and vascular disease were managed with oral anticoagulation. About half of them were also treated with concomitant antiplatelet therapy, which was associated with increased risk of bleeding, without evidence of improved cardiovascular outcomes.

B-type natriuretic peptide, disease progression and clinical outcomes in atrial fibrillation.

OBJECTIVE: The association with B-type natriuretic peptide (BNP), disease progression and outcomes in patients with atrial fibrillation (AF) has not been thoroughly investigated. METHODS: We evaluated the association between BNP levels and outcomes, including AF progression, composite outcome of major adverse cardiovascular or neurological events (MACNE) and major bleeding, via pooled logistic regression and Cox frailty models in Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II registry. AF progression was defined as either paroxysmal becoming persistent or permanent, or persistent becoming permanent at any follow-up. RESULTS: Among 13 375 patients with AF, 2797 with BNP values at baseline (median age (IQR), 72.0 (63.0-80.0) years; 43.0% women; median BNP, 238 (102-502) ng/L; 42.3% prior heart failure) were included in the models evaluating the association between BNP levels and MACNE or major bleeding. Of these, 1282 patients with paroxysmal or persistent AF at baseline were analysed in AF progression model. The likelihood of AF progression (adjusted OR, 1.11 for every 100 ng/mL; 95% CI 1.03 to 1.19) and MACNE (adjusted HR, 1.11 for every doubling in BNP values; 95% CI 1.01 to 1.22) increased with BNP concentration, while the elevated BNP values were not associated with increased risks of major bleeding. BNP values improved the risk prediction of AF progression and MACNE when added to conventional risk estimates. CONCLUSIONS: BNP levels are associated with increased risk of AF progression and cardiovascular outcomes in patients with AF. Further studies are required to assess whether biomarker-based risk stratification improves patient outcomes. CLINICAL TRIAL REGISTRATION: NCT01701817.

Association of Race/Ethnicity With Oral Anticoagulant Use in Patients With Atrial Fibrillation: Findings From the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II.

Importance: Black and Hispanic patients are less likely than white patients to use oral anticoagulants for atrial fibrillation. Little is known about racial/ethnic differences in use of direct-acting oral anticoagulants (DOACs) for atrial fibrillation. Objective: To assess racial/ethnic differences in the use of oral anticoagulants, particularly DOACs, in patients with atrial fibrillation. Design, Setting, and Participants: This cohort study used data from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II, a prospective, US-based registry of outpatients with nontransient atrial fibrillation 21 years and older who were followed up from February 2013 to July 2016. Data were analyzed from February 2017 to February 2018. Exposures: Self-reported race/ethnicity as white, black, or Hispanic. Main Outcomes and Measures: The primary outcome was use of any oral anticoagulant, particularly DOACs. Secondary outcomes included the quality of anticoagulation received and oral anticoagulant discontinuation at 1 year. Results: Of 12 417 patients, 11 100 were white individuals (88.6%), 646 were black individuals (5.2%), and 671 were Hispanic individuals (5.4%) with atrial fibrillation. After adjusting for clinical features, black individuals were less likely to receive any oral anticoagulant than white individuals (adjusted odds ratio [aOR], 0.75 [95% CI, 0.56, 0.99]) and less likely to receive DOACs if an anticoagulant was prescribed (aOR, 0.63 [95% CI, 0.49-0.83]). After further controlling for socioeconomic factors, oral anticoagulant use was no longer significantly different in black individuals (aOR, 0.78 [95% CI, 0.59-1.04]); among patients using oral anticoagulants, DOAC use remained significantly lower in black individuals (aOR, 0.73 [95% CI, 0.55-0.95]). There was no significant difference between white and Hispanic groups in use of oral anticoagulants. Among patients receiving warfarin, the median time in therapeutic range was lower in black individuals (57.1% [IQR, 39.9%-72.5%]) and Hispanic individuals (51.7% [interquartile range {IQR}, 39.1%-66.7%]) than white individuals (67.1% [IQR, 51.8%-80.6%]; P < .001). Black and Hispanic individuals treated with DOACs were more likely to receive inappropriate dosing than white individuals (black patients, 61 of 394 [15.5%]; Hispanic patients, 74 of 409 [18.1%]; white patients, 1003 of 7988 [12.6%]; P = .01). One-year persistence on oral anticoagulants was the same across groups. Conclusions and Relevance: After controlling for clinical and socioeconomic factors, black individuals were less likely than white individuals to receive DOACs for atrial fibrillation, with no difference between white and Hispanic groups. When atrial fibrillation was treated, the quality of anticoagulant use was lower in black and Hispanic individuals. Identifying modifiable causes of these disparities could improve the quality of care in atrial fibrillation.

Embolic and Other Adverse Outcomes in Symptomatic Versus Asymptomatic Patients With Atrial Fibrillation (from the ORBIT-AF Registry).

Asymptomatic atrial fibrillation (AF) is being increasingly diagnosed via implantable devices, screening, and inpatient telemetry. Management of asymptomatic AF is controversial, in part, because the associated risks have not been well described. We examined the incidence of major adverse outcomes in patients with asymptomatic versus symptomatic AF using Outcomes Registry for Better Informed Treatment of Atrial, a nationwide US registry of AF patients. We compared stroke and/or non-central nervous system (CNS) embolism, major adverse cardiovascular and neurologic events, bleeding, and death in 9,319 asymptomatic (defined by European Heart Rhythm Association score = 1 or "no symptoms") versus symptomatic patients. Overall, median (interquartile) age was 75 (67 to 82) years, 3,944 (42%) were women, and 38% versus 37% were asymptomatic based on physician versus patient-reported symptoms. Compared with those with symptoms, physician-defined asymptomatic patients were less likely to be woman (35%/47%) or be on an antiarrhythmic agent (22%/33%), but were more likely to have permanent and/or persistent AF (51%/40%). CHA2DS2-VASc scores did not vary by symptom status. After adjustment, risk of first stroke and/or non-CNS embolism (hazard ratio [HR] 0.85 [95% confidence interval {CI} 0.63 to 1.16], p = 0.32), major adverse cardiovascular and neurologic events (HR 0.88 [95% CI 0.76 to 1.03], p = 0.11), bleeding (HR 0.85 [95% CI 0.72 to 1.00], p = 0.05), and death (HR 0.99 [95% CI 0.87 to 1.13], p = 0.88) were similar in asymptomatic (European Heart Rhythm Association = 1) and symptomatic AF, respectively. Prospective, randomized studies are needed to further define associated adverse events and delineate optimal prophylactic therapies in patients with asymptomatic AF.

Characteristics and outcomes of adults with chronic obstructive pulmonary disease and atrial fibrillation.

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is associated with the development of atrial fibrillation (AF), and may complicate treatment of AF. We examined the association between COPD and symptoms, quality of life (QoL), treatment and outcomes among patients with AF. METHODS: We compared patients with and without a diagnosis of COPD in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation, a prospective registry that enrolled outpatients with AF not secondary to reversible causes, from both academic and community settings. RESULTS: Among 9749 patients with AF, 1605 (16%) had COPD. Relative to patients without COPD, those with COPD were more likely to be older, current/former smokers (73% vs 43%), have heart failure (54% vs 29%) and coronary artery disease (49% vs 34%). Oral anticoagulant and beta blocker use were similar, whereas digoxin use was more common among patients with COPD. Symptom burden was generally higher, and QoL worse, among patients with COPD (median Atrial Fibrillation Effect on QualiTy-of-Life score 76 vs 83). Patients with COPD had higher risk of all-cause mortality (adjusted HR 1.52 (95% CI 1.32 to 1.74)), cardiovascular mortality (adjusted HR 1.51 (95% CI 1.24 to 1.84)) and cardiovascular hospitalisation (adjusted HR 1.15 (95% CI 1.05 to 1.26)). Patients with COPD also had higher risk of major bleeding events (adjusted HR 1.25 (95% CI 1.05 to 1.50)). There did not appear to be associations between COPD and AF progression, ischaemic events or new-onset heart failure. CONCLUSIONS: Among patients with AF, COPD is associated with higher symptom burden, worse QoL, and worse cardiovascular and bleeding outcomes. These associations were not fully explained by cardiovascular risk factors, AF treatment or smoking history. CLINICAL REGISTRATION NUMBER: NCT01165710.

Mineralocorticoid Receptor Antagonism in Patients With Atrial Fibrillation: Findings From the ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) Registry.

BACKGROUND: Mineralocorticoid receptor antagonist (MRA) therapy may be beneficial to patients with atrial fibrillation (AF), but little is known about their use in patients with AF and subsequent outcomes. METHODS AND RESULTS: In order to better understand MRA use and subsequent outcomes, we performed a retrospective cohort study of the contemporary ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) registry. AF progression and cardiovascular outcomes were compared using propensity-matched Cox proportional hazards modeling according to MRA use at baseline and new MRA use at follow-up versus patients with no MRA use. Among 7012 patients with nonpermanent AF, 320 patients were taking MRA at enrollment, and 416 patients initiated MRA use during follow-up. The mean patient age was 72.5 years, 56.3% were men, and 70.4% had paroxysmal AF. Among all patients taking MRAs, 434 (59.0%) had heart failure, 655 (89.0%) had hypertension, and 380 (51.6%) had both. After adjustment, new MRA use was not associated with reduced AF progression (hazard ratio, 1.18; 95% confidence interval, 0.88-1.58; P=0.27) but showed a trend towards lower risk of stroke, transient ischemic attack, or systemic embolism (hazard ratio, 0.17; 95% confidence interval, 0.02-1.23; P=0.08). Results were similar for a comparison of new MRA users and baseline MRA users compared with nonusers. CONCLUSIONS: In community-based outpatients with AF, the majority of MRA use was for heart failure and hypertension. MRA use also trended towards lower adjusted stroke risk. Future studies should test the hypothesis that MRA use may decrease the risk of stroke in patients with AF.

Association of of Atrial Fibrillation Clinical Phenotypes With Treatment Patterns and Outcomes: A Multicenter Registry Study.

Importance: Atrial fibrillation (AF) is usually classified on the basis of the disease subtype. However, this characterization does not capture the full heterogeneity of AF, and a data-driven cluster analysis reveals different possible classifications of patients. Objective: To characterize patients with AF based on a cluster analysis and to evaluate the association between these phenotypes, treatment, and clinical outcomes. Design, Setting, and Participants: This cluster analysis used data from an observational cohort that included 9749 patients with AF who had been admitted to 174 US sites participating in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry. Data analysis was completed from January 2017 to October 2017. Exposure: Patients with diagnosed AF who were included in the registry. Main Outcomes and Measures: Composite of major adverse cardiovascular or neurological events and major bleeding, as defined by the International Society of Thrombosis and Hemostasis criteria. Results: Of 9749 total patients, 4150 (42.6%) were female; 8719 (89.4%) were white and 477 (4.9%) were African American. A cluster analysis was performed using 60 baseline clinical characteristics, and it classified patients with AF into 4 statistically driven clusters: (1) those with considerably lower rates of risk factors and comorbidities than all other clusters (n = 4673); (2) those with AF at younger ages and/or with comorbid behavioral disorders (n = 963); (3) those with AF who had similarities to patients with tachycardia-brachycardia and had device implantation owing to sinus node dysfunction (n = 1651); and (4) those with AF and prior coronary artery disease, myocardial infarction, and/or atherosclerotic comorbidities (n = 2462). Conventional classifications, such as AF subtype and left atrial size, did not drive cluster formation. Compared with the low comorbidity AF cluster, adjusted risks of major adverse cardiovascular or neurological events were significantly higher in the other 3 clusters (behavioral comorbidity cluster: hazard ratio [HR], 1.49; 95% CI, 1.10-2.00; device implantation cluster: HR, 1.39; 95% CI, 1.15-1.68; and atherosclerotic comorbidity cluster: HR, 1.59; 95% CI, 1.31-1.92). For major bleeding, adjusted risks were higher in the behavioral disorder comorbidity cluster (HR, 1.35; 95% CI, 1.05-1.73), those with device implantation (HR, 1.24; 95% CI, 1.05-1.47), and those with atherosclerotic comorbidities (HR, 1.13; 95% CI, 0.96-1.33) compared with the low comorbidity cluster. The same clusters were identified in an external validation in the ORBIT AF II registry. Conclusions and Relevance: Cluster analysis identified 4 clinically relevant phenotypes of AF that each have distinct associations with clinical outcomes, underscoring the heterogeneity of AF and importance of comorbidities and substrates.

Patients' time in therapeutic range on warfarin among US patients with atrial fibrillation: Results from ORBIT-AF registry.

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.

Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II: rationale and design of the ORBIT-AF II registry.

BACKGROUND: Recent clinical trials have demonstrated the safety and efficacy of several non-vitamin K oral anticoagulants (NOACs) for the treatment of atrial fibrillation (AF). However, there are limited data on their use and outcomes in routine clinical practice, particularly among patients newly diagnosed as having AF and patients with AF recently transitioned to a NOAC. METHODS/DESIGN: ORBIT-AF II is a multicenter, national registry of patients with AF that is enrolling up to 15,000 newly diagnosed patients with AF and/or those with AF recently transitioned to a NOAC from 300 US outpatient practices. These patients will be followed for up to 2 years, including clinical status, outcomes (major adverse cardiovascular events, bleeding), and management of anticoagulation surrounding bleeding events. In addition, detailed data regarding the use of these agents in and around cardiac procedures, their complications, and management of such complications will be collected. CONCLUSIONS: The ORBIT-AF II registry will provide valuable insights into the safety and effectiveness of NOACs used in AF in community practice settings.