Background Oral anticoagulation ( OAC ) reduces stroke risk in atrial fibrillation, but bleeding is a frequent side effect. The decision to discontinue or modify medication regimens in response to a bleeding event may differ according to bleeding site and severity. Methods and Results We used data from a large, national outpatient registry, ORBIT ‐ AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation; 2010–2011), to evaluate event characteristics and OAC management following the first bleeding event occurring during follow‐up. Bleeding events were classified into 3 categories: (1) International Society of Thrombosis and Hemostasis major bleeding, (2) clinically relevant nonmajor bleeding requiring medical attention, and (3) nuisance bleeding not requiring medical attention (eg, bruising, hemorrhoidal bleeding). Of 9743 patients enrolled in ORBIT ‐ AF with follow‐up data, 510 (3.23/100 subject‐years) experienced a major bleed, 615 (3.90/100 subject‐years), experienced a clinically relevant nonmajor bleed, and 1558 (9.87/100 subject‐years) experienced a nuisance bleed, among first bleeds over 2 years. Nearly one third of patients (31.6%) discontinued OAC therapy following a major bleeding event, 12.7% following a clinically relevant nonmajor bleed, and 4.5% following a nuisance bleed. Compared with those who experienced a clinically relevant nonmajor or nuisance bleed, patients who experienced a major bleed were more likely to be black and female and to have a history of heart failure and stroke. Those who discontinued were more likely to have central nervous system or gastrointestinal bleeding than those who persisted on OAC therapy. Conclusions Overall, 1 in 3 patients who experienced a major bleed was no longer anticoagulated after the event. Those who discontinued OAC were more likely to have central nervous system or gastrointestinal bleeding than those who persisted on OAC .
Prognostic Significance of Nuisance Bleeding in Anticoagulated Patients With Atrial Fibrillation
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.
Early Adoption of Dabigatran and Its Dosing in US Patients With Atrial Fibrillation: Results From the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation
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 CHADS 2 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: NCT 01165710.
Provider Specialty and Atrial Fibrillation Treatment Strategies in United States Community Practice: Findings From the ORBIT‐AF Registry
Background The prevalence of atrial fibrillation ( AF ) continues to increase; however, there are limited data describing the division of care among practitioners in the community and whether care differs depending on provider specialty. Methods and Results Using the Outcomes Registry for Better Informed Treatment of AF ( ORBIT ‐ AF ) Registry, we described patient characteristics and AF management strategies in ambulatory clinic practice settings, including electrophysiology ( EP ), general cardiology, and primary care. A total of 10 097 patients were included; of these, 1544 (15.3%) were cared for by an EP provider, 6584 (65.2%) by a cardiology provider, and 1969 (19.5%) by an internal medicine/primary care provider. Compared with those patients who were cared for by cardiologists or internal medicine/primary care providers, patients cared for by EP providers were younger (median age, 73 years [interquartile range, IQR , 64, 80 years, Q1, Q3] versus 75 years [ IQR , 67, 82 years] for cardiology and versus 76 years [ IQR , 68, 82 years] for primary care). Compared with cardiology and internal medicine/primary care providers, EP providers used rhythm control (versus rate control) management more often (44.2% versus 29.7% and 28.8%, respectively, P <0.0001; adjusted odds ratio [ OR ] EP versus cardiology, 1.66 [95% confidence interval, CI , 1.05 to 2.61]; adjusted OR for internal medicine/primary care versus cardiology, 0.91 [95% CI , 0.65 to 1.26]). Use of oral anticoagulant therapy was high across all providers, although it was higher for cardiology and EP providers (overall, 76.1%; P =0.02 for difference between groups). Conclusions Our data demonstrate important differences between provider specialties, the demographics of the AF patient population treated, and treatment strategies—particularly for rhythm control and anticoagulation therapy.