Objective

Atrial fibrillation (AF) often progresses from paroxysmal or persistent to more sustained forms, but the rate and predictors of AF progression in clinical practice are not well described.

Methods

Using the Outcomes Registry for Better Informed Treatment of AF, we analysed the incidence and predictors of progression and tested the discrimination and calibration of the HATCH (hypertension, age, TIA/stroke, chronic obstructive pulmonary disease, heart failure) and CHA₂DS₂VASc scores for identifying AF progression.

Results

Among 6235 patients with paroxysmal or persistent AF at baseline, 1479 progressed, during follow-up (median 18 (IQR 12-24) months). These patients were older and had more comorbidities than patients who did not progress (CHADS₂ 2.3±1.3 vs 2.1±1.3, p<0.0001). At baseline, patients with AF progression were more often on a rate control as opposed to a rhythm control strategy (66 vs 56%, p<0.0001) and had higher heart rate (72(64-80) vs 68(60-76) bpm, p<0.0001). The strongest predictors of AF progression were AF on the baseline ECG (OR 2.30, 95% CI 1.95 to 2.73, p<0.0001) and increasing age (OR 1.16, 95% CI1.09 to 1.24, p<0.0001, per 10 increase), while patients with lower heart rate (OR 0.84, 95% CI 0.79 to 0.89, p<0.0001, per 10 decrease ≤80) were less likely to progress. There was no significant interaction between rhythm on baseline ECG and heart rate (p=0.71). The HATCH and CHA₂DS₂VASc scores had modest discriminatory power for AF progression (C-indices 0.55 (95% CI 0.53 to 0.58) and 0.55 (95% CI 0.52 to 0.57)).

Conclusions

Within 1.5 years, almost a quarter of the patients with paroxysmal or persistent AF progress to a more sustained form. Progression is strongly associated with heart rate, and age.

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.

Background

As treatment options for atrial fibrillation (AF) increase, more attention is focused on patients' experiences and quality of life (QoL). However, little is known about the factors associated with these outcomes.

Methods

The Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) is a disease-specific QoL tool for AF, with domain and summary scores ranging from 0 (the worst QoL) to 100. Using multivariable linear regression, we evaluated factors associated with baseline AFEQT Summary and Subscale Scores in ORBIT AF, a large, community-based AF registry. Independent associations were reported as coefficient estimates in scores and 95% confidence intervals (CI).

Results

Overall, AFEQT was assessed in 2007 AF outpatients from 99 sites. Median age (IQR) was 76 years (67-82) and 43% were female. The median AFEQT summary score was 82 (67-94). Female sex, younger age, new onset AF, higher heart rate, obstructive sleep apnea, symptomatic heart failure (HF), chronic obstructive pulmonary disease and coronary artery disease were all independently associated with reduced QoL. Female sex [Estimate -7.03, 95% CI (-9.31, -4.75)] and new onset versus permanent AF [Estimate -7.44, 95% CI (-11.03, -3.84)] were independently associated with increased symptoms. NYHA Class III or IV HF [Estimate -14.44, 95% CI (-19.46, -8.76)] and female sex [Estimate -7.91, 95% CI (-9.95, -5.88)] were most independently associated with impaired daily activities.

Conclusions

QoL in patients with AF varies widely and is associated with several patient factors. Understanding patient factors independently associated with worse QoL can be a foundation for tailoring treatment.

Background

Patients with sinus node dysfunction (SND) have increased risk of atrial tachyarrhythmias, including atrial fibrillation (AF). To date, treatment patterns and outcomes of patients with SND and AF have not been well described.

Hypothesis

Patients with SND and AF have higher risk of adverse cardiovascular outcomes.

Methods

Sinus node dysfunction was defined clinically, based on treating physician. Treatment patterns were described and logistic regression analysis performed to assess outcomes.

Results

Overall, 1710 (17.7%) out of 9631 patients had SND at enrollment. Patients with SND and AF had increased comorbid medical illnesses, more severe symptoms (European Heart Rhythm Association class IV: 17.5% vs 13.9%; P = 0.0007), and poorer quality of life (median 12-month Atrial Fibrillation Effect on Quality of Life score: 79.6 vs 85.2; P = 0.0008). There were no differences in AF management strategy between patients with SND and those without (rate control, 69.7% vs 67.7%; rhythm control, 30.0% vs 32.0%; P = 0.11). After adjustment, patients with SND were more likely than those without SND to progress from paroxysmal AF at baseline to persistent or permanent AF at any follow-up, or persistent AF at baseline to permanent AF at any follow-up (odds ratio: 1.23, 95% confidence interval: 1.01-1.49, P = 0.035). However, there was no association between SND and major risk-adjusted outcomes.

Conclusions

Sinus node dysfunction is present in 1 of 6 patients with AF and is associated with increased comorbidities and higher symptom burden. However, SND is not associated with an increase in major risk-adjusted outcomes.

Aims

To determine the extent of shared decision-making (SDM), during selection of oral anticoagulant (OAC) and rhythm control treatments, in patients with newly diagnosed atrial fibrillation (AF).

Methods and results

We evaluated survey data from 1006 patients with new-onset AF enrolled at 56 US sites participating in the SATELLITE substudy of the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT II). Patients completed surveys at enrolment and at 6-month follow-up. Patients were asked about who made their AF treatment decisions. Shared decision-making was classified as one that the patient felt was an autonomous decision or a shared decision with their healthcare provider (HCP). Approximately half of patients reported that their OAC treatment decisions were made entirely by their HCP. Compared with those reporting no SDM, patients reporting SDM for OAC were more often female (47.2% vs. 38.4%), while patients reporting SDM for rhythm control were more often male (62.2% vs. 57.6%). The most important factors cited by patients during decision-making for OAC were reducing stroke and bleeding risk, and their HCP's recommendations. After adjustment, patients with self-reported understanding of OAC, and rhythm control options, had higher odds of having participated in SDM [odds ratio (OR) 2.54, confidence interval (CI): 1.75-3.68 and OR 2.36, CI: 1.50-3.71, both P ≤ 0.001, respectively].

Conclusion

Shared decision-making is not widely implemented in contemporary AF practice. Patient understanding about available therapeutic options is associated with a more than a two-fold higher likelihood of SDM, and may be a potential target for future interventions.

Background

Most patients with atrial fibrillation (AF) require rate control; however, the optimal target heart rate remains under debate. We aimed to assess rate control and subsequent outcomes among patients with permanent AF.

Methods and results

We studied 2812 US outpatients with permanent AF in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation. Resting heart rate was measured longitudinally and used as a time-dependent covariate in multivariable Cox models of all-cause and cause-specific mortality during a median follow-up of 24 months. At baseline, 7.4% (n=207) had resting heart rate <60 beats per minute (bpm), 62% (n=1755) 60 to 79 bpm, 29% (n=817) 80 to 109 bpm, and 1.2% (n=33) ≥110 bpm. Groups did not differ by age, previous cerebrovascular disease, heart failure status, CHA2DS2-VASc scores, renal function, or left ventricular function. There were significant differences in race (P=0.001), sinus node dysfunction (P=0.004), and treatment with calcium-channel blockers (P=0.006) and anticoagulation (P=0.009). In analyses of continuous heart rates, lower heart rate ≤65 bpm was associated with higher all-cause mortality (adjusted hazard ratio [HR], 1.15 per 5-bpm decrease; 95% CI, 1.01 to 1.32; P=0.04). Similarly, increasing heart rate >65 bpm was associated with higher all-cause mortality (adjusted HR, 1.10 per 5-bpm increase; 95% CI, 1.05 to 1.15; P<0.0001). This relationship was consistent across endpoints and in a broader sensitivity analysis of permanent and nonpermanent AF patients.

Conclusions

Among patients with permanent AF, there is a J-shaped relationship between heart rate and mortality. These data support current guideline recommendations, and clinical trials are warranted to determine optimal rate control.

Clinical trial registration

URL: http://clinicaltrials.gov/. Unique identifier: NCT01165710.

Background Chronic kidney disease ( CKD ) is a common comorbidity in patients with atrial fibrillation. The presence of CKD complicates drug selection for stroke prevention and rhythm control. Methods and Results Patients enrolled in ORBIT AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) with baseline renal function and follow-up data were included (N=9019). CKD was defined as an estimated creatinine clearance <60 mL /min. Patient characteristics were compared by CKD status, and Cox proportional hazards modeling was used to examine the association between oral anticoagulant ( OAC ) use and outcomes and antiarrhythmic drug use and outcomes stratified by CKD stages. At enrollment, 3490 (39%) patients had an estimated creatinine clearance <60 mL /min. Patients with CKD were older and had higher CHA ₂ DS ₂ VAS c and Anticoagulant and Risk Factors in Atrial Fibrillation (ATRIA) scores. A rhythm control strategy was selected less frequently in patients with CKD , while OAC use was lower among Stage IV and V CKD patients. After adjustment, no significant interaction was noted for OAC and CKD on all-cause mortality ( P=0.5442) or cardiovascular death ( P=0.1233), although a trend for increased major bleeding ( P=0.0608) and stroke, systemic embolism or transient ischemic attack ( P=0.0671) was observed. No interaction was noted for antiarrhythmic drug use and CKD status on all-cause mortality ( P=0.9706), or stroke, systemic embolism or transient ischemic attack ( P=0.4218). Conclusions Patients with atrial fibrillation and CKD are less likely to be treated with rhythm control. Patients with advanced CKD are less likely to receive OAC . Finally, outcomes with OAC in patients with advanced CKD may be materially different with higher rates of both bleeding and stroke.

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. 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. 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. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01701817.

Background

Obstructive sleep apnea (OSA) is a known risk factor for atrial fibrillation (AF). However, it remains unclear whether OSA is independently associated with worse cardiovascular and neurological outcomes in patients with AF.

Methods

We used the ORBIT-AF I and ORBIT-AF II to conduct a retrospective cohort study of 22,760 patients with AF with and without OSA. Adjusted multivariable Cox proportional hazards models was used to determine whether OSA was associated with increased risk for major adverse cardiac and neurologic events (MACNEs) (cardiovascular death, myocardial infarction, stroke/transient ischemic attack/non-central nervous system embolism (stroke/SE), and new-onset heart failure], combined and individually.

Results

A total of 4,045 (17.8%) patients had OSA at baseline. Median follow-up time was 1.5 (interquartile range: 1-2.2) years, and 1,895 patients experienced a MACNE. OSA patients were younger (median [interquartile range] 68 [61-75] years vs 74 [66-81] years), were more likely male (70.7% vs 55.3%), and had increased body mass index (median 34.6 kg/m² [29.8-40.2] vs 28.7 kg/m² [25.2-33.0]). Those with OSA had a higher prevalence of concomitant comorbidities such as diabetes, chronic obstructive pulmonary disease, and heart failure. OSA patients had higher use of antithrombotic therapy. After adjustment, the presence of OSA was significantly associated with MACNE (hazard ratio: 1.16 [95% CI: 1.03-1.31], P = .011). OSA was also an independent risk factor for stroke/SE beyond the CHA₂DS₂-VASc risk factors (HR: 1.38 [95% CI 1.12-1.70], P = .003) but not cardiovascular death, myocardial infarction, new-onset heart failure, or major bleeding.

Conclusions

Among patients with AF, OSA is an independent risk factor for MACNE and, more specifically, stroke/SE.

Background

Comorbidities are common in patients with atrial fibrillation (AF) and affect prognosis, yet are often undertreated. However, contemporary rates of use of guideline-directed therapies (GDT) for non-AF comorbidities and their association with outcomes are not well described.

Methods

We used the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF) to test the association between GDT for non-AF comorbidities and major adverse cardiac or neurovascular events (MACNE; cardiovascular death, myocardial infarction, stroke/thromboembolism, or new-onset heart failure), all-cause mortality, new-onset heart failure, and AF progression. Adjustment was performed using Cox proportional hazards models and logistic regression.

Results

Only 6,782 (33%) of the 20,434 patients eligible for 1 or more GDT for non-AF comorbidities received all indicated therapies. Use of all comorbidity-specific GDT was highest for patients with hyperlipidemia (75.6%) and lowest for those with diabetes mellitus (43.1%). Use of "all eligible" GDT was associated with a nonsignificant trend toward lower rates of MACNE (HR 0.90 [0.79-1.02]) and all-cause mortality (HR 0.90 [0.80-1.01]). Use of GDT for heart failure was associated with a lower risk of all-cause mortality (HR 0.77 [0.67-0.89]), and treatment of obstructive sleep apnea was associated with a lower risk of AF progression (OR 0.75 [0.62-0.90]).

Conclusions

In AF patients, there is underuse of GDT for non-AF comorbidities. The association between GDT use and outcomes was strongest in heart failure and obstructive sleep apnea patients where use of GDT was associated with lower mortality and less AF progression.