Temporal Trends in Medication Use and Outcomes in Atrial Fibrillation

Trends over time in oral anticoagulation and stroke rates in atrial fibrillation: A community-based study

OBJECTIVES

Over the last decade, direct oral anticoagulants (DOAC) have become preferred over warfarin for stroke prevention in atrial fibrillation (AF). The objectives of this study were to quantify the shift over time from warfarin to DOACs and parallel changes in ischemic and hemorrhagic stroke rates in AF.

MATERIALS AND METHODS

This community-based retrospective study was undertaken within a single integrated health care network from 2011 to 2021. Changes over time in warfarin and DOAC use were quantified by year, both overall and stratified by CHA2DS2-VASc score. Ischemic and hemorrhagic stroke rate changes over time were evaluated by Poisson regression. Stroke rates were evaluated in different time eras: 2011-2015 and 2016-2021.

RESULTS

Among 31,978 AF patients followed an average of 5.5 years, any OAC use increased from 50.2 % (2011) to 59.4 % (2020) (p < 0.001). Warfarin use decreased from 49.3 % to 30.8 %, while DOAC use increased from 2.0 % to 30.8 % (both p < 0.001). In 2020, patients with CHA2DS2-VASc 0-1 and 2-5 were more likely to use DOACs than warfarin (18.6 % vs. 6.7 %; 33.0 % vs. 28.2 %), whereas in CHA2DS2-VASc 6-9 DOACs were used less frequently (30.0 % vs. 40.8 %). Ischemic stroke rates significantly increased by 19 % (95 % CI: 7 %, 32 %) from 2011 to 2015, but significantly decreased by 18 % (10 %, 26 %) from 2016 to 2021. Hemorrhagic stroke rates stabilized in 2016-2021 (+3 %; -18 %, 30 %) after increasing in 2011-2015 (+36 %; 4 %, 78 %).

CONCLUSION

Improvements in ischemic and hemorrhagic stroke rates coincided temporally with increased uptake of OACs and a shift toward increased uptake of DOACs relative to warfarin.

Trends in treatment and outcomes of atrial fibrillation during 2007-17 in Finland

AIMS

Guidelines on the management of atrial fibrillation (AF) have evolved significantly during the past two decades, but the concurrent developments in real-life management and prognosis of AF are unknown. We assessed trends in the treatment and outcomes of patients with incident AF between 2007 and 2017.

METHODS AND RESULTS

The registry-based nationwide FinACAF (Finnish AntiCoagulation in Atrial Fibrillation) cohort covers all patients with AF in Finland from all levels of care. We determined the proportion of patients who were treated with oral anticoagulants (OACs) or rhythm control therapies, experienced an ischaemic stroke or bleeding event requiring hospitalization, or died within 1-year follow-up after AF diagnosis. We identified 206 909 patients (mean age 72.6 years) with incident AF. During the study period, use of OACs increased from 43.6 to 76.3%, and the increase was most evident in patients with at least moderate stroke risk. One-year mortality decreased from 13.3 to 10.6%, and the ischaemic stroke rate from 5.3 to 2.2%. The prognosis especially improved in patients over 75 years of age. Concurrently, a small increase in major bleeding events was observed. Use of catheter ablation increased continuously over the study period, but use of other rhythm-control therapies decreased after 2013.

CONCLUSION

Stroke prevention with OACs in patients with incident AF improved considerably from 2007 to 2017 in Finland. This development was accompanied by decreasing 1-year mortality and the reduction of the ischaemic stroke rate by more than half, particularly among elderly patients, whereas there was only slight increase in severe bleeding events.

Temporal changes in incidence, treatment strategies and 1-year re-admission rates in patients with atrial fibrillation/flutter under 65 years of age: A Danish nationwide study

AIM

To examine temporal changes in incidence rates of atrial fibrillation/flutter (AF), treatment strategies, and AF readmission rates in patients <65 years.

METHODS

Using Danish nationwide registries, we identified patients <65 years with a first-time AF diagnosis from 2000 to 2018. The cohort was categorized according to calendar periods; 2000-2002, 2003-2006, 2007-2010, 2011-2014, and 2015-2018. In this retrospective cohort study the incidence rate (IR) of AF per 100,000 person years (PY), catheter ablation, electrical cardioversion, use of pharmacotherapy, and AF readmission, were investigated in the first year following AF diagnosis.

RESULTS

We identified 60,917 patients; 8150 (13.4%) in 2000-2002, 11,898 (19.5%) in 2003-2006, 13,560 (22.3%) in 2007-2010, 14,167 (23.3%) in 2011-2014, and 13,142 (21.6%) in 2015-2018. Apart from 2015 to 2018, a stepwise increase in the crude IR of AF was observed across calendar periods; 2000-2002: 78.7 (95% CI 77.0;80.4), 2003-2006: 86.3 (84.7;87.8), 2007-2010: 97.9 (96.3;99.6), 2011-2014: 102.3 (100.7;104.0), 2015-2018: 93.6 (92.0;95.2). Over the studied time-periods, we found a stepwise increase in the cumulative incidence of catheter ablation (1.2% to 7.6%) electrical cardioversion (2.0% to 8.7%) and treatment with oral anticoagulant therapy (OAC) (28.5% to 47.8%) within the first year of diagnosis. No temporal differences in incidence of 1-year AF readmission were identified (AF-readmissions: 2000-2002: 32.7%, 2003-2006: 31.1%, 2007-2010: 32.2%, 2011-2014: 32.1% and 2015-2018: 31.7%).

CONCLUSION

The incidence rate of AF in patients <65 years increased from 2000 to 2018, as did the use of catheter ablation, electrical cardioversion and OAC in the first year following AF diagnosis. 1-year AF readmission incidence remained stable around 32% over the study period.

Rhythm- or rate-control strategies according to 4S-AF characterization scheme and long-term outcomes in atrial fibrillation patients: the FAMo (Fibrillazione Atriale in Modena) cohort

The 4S-AF scheme [Stroke risk, Symptom severity, Severity of atrial fibrillation (AF) burden, Substrate severity] was recently proposed to characterize AF patients. In this post hoc analysis we evaluated the agreement between the therapeutic strategy (rate or rhythm control, respectively), as suggested by the 4S-AF scheme, and the actual strategy followed in a patients cohort. Outcomes of interest were as follows: all-cause death, a composite of all-cause death/any thromboembolism/acute coronary syndrome, and a composite of all-cause death, any thrombotic/ischemic event, and major bleeding (net clinical outcome). We enrolled 615 patients: 60.5% male, median age 74 [interquartile range (IQR) 67-80] years; median CHA₂DS₂VASc 4 and median HAS-BLED 2. The 4S-AF score would have suggested a rhythm-control strategy in 351 (57.1%) patients while a rate control in 264 (42.9%). The strategy adopted was concordant with the 4S-AF suggestions in 342 (55.6%) cases, and non-concordant in 273 (44.4%). After a median follow-up of 941 days (IQR 365-1282), 113 (18.4%) patients died, 158 (25.7%) had an event of the composite endpoint. On adjusted Cox regression analysis, when 4S-AF score suggested rate control, disagreement with that suggestion was not associated with a worse outcome. When 4S-AF indicated rhythm control, disagreement was associated with a higher risk of all-cause death (HR 7.59; 95% CI 1.65-35.01), and of the composite outcome (HR 2.69; 95% CI 1.19-6.06). The 4S-AF scheme is a useful tool to comprehensively evaluate AF patients and aid the decision-making process. Disagreement with the rhythm control suggestion of the 4S-AF scheme was associated with adverse clinical outcomes.

Digoxin Use in Atrial Fibrillation; Insights from National Ambulatory Medical Care Survey

OBJECTIVE

To evaluate the characteristics and trends of digoxin use during outpatient visits with atrial fibrillation in the US from 2006 to 2015.

METHODS

We conducted a retrospective analysis of adult (age ≥18) patient visits to office-based physicians from National Ambulatory Medical Care Survey (NAMCS) database between 2006-2015. The International Classification of Diseases, Ninth Revision, Clinical Modification codes were used to identify patients with atrial fibrillation. Visits in which digoxin was listed as a medication were analyzed with descriptive statistics. Multivariable logistic regression analysis was used to identify the predictors of digoxin usage.

RESULTS

Of a weighted sample of 108,113,894 patient visits, 17,617,853 (16.3%) visits included use of digoxin. Patients who used digoxin had a mean age of 75 ± 0.7 years and were predominantly Caucasian (92.56%). Among the patients who used digoxin, 24% had a diagnosis of heart failure. Multivariate analysis showed that the increased likelihood of digoxin utilization was associated with female sex (adjusted odds ratio [aOR] 1.34, 95% CI 1.05-1.71, p = .019), heart failure (aOR 1.51, 95% CI 1.05-1.17, p = .025), and usage of ³5 medications (aOR 5.32, 95% CI 3.67-7.71, p = <0.001). Among the visits with atrial fibrillation, the percentage of visits with digoxin usage decreased from 23% in 2006 to 9% in 2013 and then again increased to 14% in 2015(P-trend <0.001).

CONCLUSION

This is the first study to examine the use of digoxin in atrial fibrillation patients in a large outpatient setting. During 2006-2015, the percentage of digoxin prescriptions in atrial fibrillation patients has declined. Predictors of digoxin use in atrial fibrillation patients are female sex, congestive heart failure, and higher number of concurrent medications.

Mortality in atrial fibrillation. Is it changing?

Patients with atrial fibrillation experience higher mortality rates than those without this condition. Recent studies have explored whether mortality rates in atrial fibrillation patients and the overall impact of atrial fibrillation on mortality has changed. Overall, mortality in atrial fibrillation has decreased over the last few decades, with no strong differences between men and women. These improvements could be caused by advances in preventing thromboembolic complications of atrial fibrillation or better management of comorbidities in these patients. Understanding the mechanisms for these changes and developing novel approaches to improve survival in AF patients are areas deserving of future research.

Temporal Trends in Population Rates of Incident Atrial Fibrillation and Atrial Flutter Hospitalizations, Stroke Risk, and Mortality Show Decline in Hospitalizations

BACKGROUND

Hospitalization for nonvalvular atrial fibrillation (NVAF) is common and results in substantial cost burden. Current national data trends for the incidence, stroke risk profiles, and mortality of hospitalization for NVAF and atrial flutter (AFL) are sparse.

METHODS

The Canadian Institute of Health Information Discharge Abstract Database was used to identify patients ≥ 20 years with incident NVAF/AFL (NVAF, ICD-9 code 427.3 or ICD-10 I48) in any diagnosis field from 2006 to 2015 in Canada, except Québec. National and provincial trends in rate over time (rate ratio, 95% confidence interval [CI]) were calculated for age-sex standardized hospitalizations. Trends in stroke risk profiles and in-hospital mortality rates adjusted for stroke risk factors were also calculated.

RESULTS

A total of 578,947 patients were hospitalized with incident NVAF/AFL. The median age was 77 years (interquartile range: 68-84), 82% were ≥ 65 years, 54% were men, 54% had a CHADS2 ≥ 2, and 69% had a CHA2DS2-Vasc ≥ 3. The overall age- and sex-standardized rate of NVAF/AFL hospitalization was 315 per 100,000 population and declined by 2% per year (P < 0.001). There was an annual rate decline in NVAF/AFL hospitalizations in every province. The majority of hospitalized patients are at high risk of stroke, and this risk remained unchanged. The average adjusted in-hospital mortality was 8.80 per 100 patients 95% CI, 8.80-8.81 with a 2% annual decline in rate (P < 0.001).

CONCLUSION

Between 2006 and 2015, we found national and provincial hospitalization rates for incident NVAF/AFL are declining. The majority of patients are at high risk for stroke. In-hospital mortality has declined but remains substantial.

Risk of traumatic intracranial haemorrhage is increased in older people exposed to oral anticoagulation with phenprocoumon

BACKGROUND

Hospital admissions resulting from traumatic intracranial haemorrhages (TIH) in older people are increasing. There are concerns regarding an increased risk of a TIH in people taking oral anticoagulants (OAC) like phenprocoumon.

AIMS

The aim of this study was to estimate the incremental risk of a TIH associated with OAC in older people. Furthermore, this study explored differences in risk according to functional status.

METHODS

The study took data from a large German health insurance provider and combined hospital diagnoses with data regarding drug dispensing to estimate rates of a TIH in people with and without exposure to phenprocoumon. Analyses were stratified by sex and by severe functional impairment as disclosed by the long-term care insurance provider.

RESULTS

Overall, exposure to OAC resulted in 2.7 times higher rates of TIH. People with severe functional impairment had a higher baseline risk of TIH than people without severe functional impairment. However, the incremental risk in those exposed to OAC was similar among people with and without severe functional impairment (standardised incidence rate difference 15.73 (95% CI 7.84; 23.61) and 12.10 (95% CI 9.63; 14.57) per 10,000 person-years, respectively).

CONCLUSIONS

OAC increases the risk of TIH considerably. The incremental risk of TIH in those exposed to OAC is comparable between people with and without severe functional impairment. The presence of severe functional impairment per se should not exclude such patients from the potential benefits of OAC. For now, the prescription should be personalized based on individual fall risk factors and risk-taking behaviour.

Evidence-Practice Gaps in Postdischarge Initiation With Oral Anticoagulants in Patients With Atrial Fibrillation

Background

Oral anticoagulant (OAC) therapy reduces the risk of stroke in people with atrial fibrillation (AF), and is considered best practice; however, there is little Australian evidence around the uptake of OACs in this population.

Methods and Results

We used linked hospital admissions, pharmaceutical dispensing claims, medical services, and mortality data for people in Australia's 2 most populous states (July 2010 to June 2015). Among OAC‐naïve people hospitalized with AF, we estimated initiation of OAC therapy within 30 days of discharge, and persistence with therapy in the first year. We analyzed both outcomes using multivariable Cox regression. In 71 184 people with AF (median age 78 years, 49% female), 22.7% initiated OAC therapy. Initiation was lowest in July to December 2011 (17.0%) and highest in July to December 2014 (30.1%) after subsidy of the direct OACs. In adjusted analyses, initiation was most likely in people with a CHA₂DS₂‐VA score ≥7 (versus 0) (hazard ratio=6.25, 95% CI 5.08–7.69), and a history of venous thromboembolism (hazard ratio=2.65, 95% CI 2.49–2.83). Of the people who initiated OAC therapy, 39.9% discontinued within 1 year; a lower risk of discontinuation was associated with a CHA₂DS₂‐VA score ≥7 (versus 0) (hazard ratio=0.22, 95% CI 0.14–0.35), or initiation on a direct OAC (versus warfarin) (hazard ratio=0.55, 95% CI 0.50–0.60).

Conclusions

We found that OAC therapy was severely underutilized in people hospitalized with AF, even among high‐risk individuals. Reasons for this underuse, whether patient, prescriber, or hospital related, should be identified and addressed to reduce stroke‐related morbidity and mortality in people with AF.

Reducing Stroke Risk in Atrial Fibrillation: Adherence to Guidelines Has Improved, but Patient Persistence with Anticoagulant Therapy Remains Suboptimal

Atrial fibrillation (AF) is a significant risk factor for avoidable stroke. Among high-risk patients with AF, stroke risk can be mitigated using oral anticoagulants (OACs), however reduction is largely contingent on physician prescription and patient persistence with OAC therapy. Over the past decade significant advances have occurred, with revisions to clinical practice guidelines relating to management of stroke risk in AF in several countries, and the introduction of non-vitamin K antagonist OACs (NOACs). This paper summarises the evolving body of research examining guideline-based clinician prescription over the past decade, and patient-level factors associated with OAC persistence. The review shows clinicians' management over the past decade has increasingly reflected guideline recommendations, with an increasing proportion of high-risk patients receiving OACs, driven by an upswing in NOACs. However, a treatment gap remains, as 25–35% of high-risk patients still do not receive OAC treatment, with great variation between countries. Reduction in stroke risk directly relates to level of OAC prescription and therapy persistence. Persistence and adherence to OAC thromboprophylaxis remains an ongoing issue, with 2-year persistence as low as 50%, again with wide variation between countries and practice settings. Multiple patient-level factors contribute to poor persistence, in addition to concerns about bleeding. Considered review of individual patient's factors and circumstances will assist clinicians to implement appropriate strategies to address poor persistence. This review highlights the interplay of both clinician's awareness of guideline recommendations and understanding of individual patient-level factors which impact adherence and persistence, which are required to reduce the incidence of preventable stroke attributable to AF.

Personalized Anticoagulation: Optimizing Warfarin Management Using Genetics and Simulated Clinical Trials

BACKGROUND

Clinical trials testing pharmacogenomic-guided warfarin dosing for patients with atrial fibrillation have demonstrated conflicting results. Non-vitamin K antagonist oral anticoagulants are expensive and contraindicated for several conditions. A strategy optimizing anticoagulant selection remains an unmet clinical need.

METHODS AND RESULTS

Characteristics from 14 206 patients with atrial fibrillation were integrated into a validated warfarin clinical trial simulation framework using iterative Bayesian network modeling and a pharmacokinetic-pharmacodynamic model. Individual dose-response for patients was simulated for 5 warfarin protocols-a fixed-dose protocol, a clinically guided protocol, and 3 increasingly complex pharmacogenomic-guided protocols. For each protocol, a complexity score was calculated using the variables predicting warfarin dose and the number of predefined international normalized ratio (INR) thresholds for each adjusted dose. Study outcomes included optimal time in therapeutic range ≥65% and clinical events. A combination of age and genotype identified different optimal protocols for various subpopulations. A fixed-dose protocol provided well-controlled INR only in normal responders ≥65, whereas for normal responders <65 years old, a clinically guided protocol was necessary to achieve well-controlled INR. Sensitive responders ≥65 and <65 and highly sensitive responders ≥65 years old required pharmacogenomic-guided protocols to achieve well-controlled INR. However, highly sensitive responders <65 years old did not achieve well-controlled INR and had higher associated clinical events rates than other subpopulations.

CONCLUSIONS

Under the assumptions of this simulation, patients with atrial fibrillation can be triaged to an optimal warfarin therapy protocol by age and genotype. Clinicians should consider alternative anticoagulation therapy for patients with suboptimal outcomes under any warfarin protocol.

Optimizing primary care management of atrial fibrillation: The rationale and methods of the Integrated Management Program Advancing Community Treatment of Atrial Fibrillation (IMPACT-AF) study

The Integrated Management Program Advancing Community Treatment of Atrial Fibrillation (IMPACT-AF) is an investigator designed, prospective, randomized, un-blinded, cluster design clinical trial, conducted in the primary care setting of Nova Scotia, Canada. Its aim is to evaluate whether an electronic Clinical Decision Support System (CDSS) designed to assist both practitioners and patients with evidence-based management strategies for Atrial Fibrillation (AF) can improve process of care and outcomes in a cost-efficient manner as compared to usual AF care. At least 200 primary care providers are being recruited and randomized at the level of the practice to control (usual care) or intervention (eligible to access to CDSS) cohorts. Over 1,000 patients of participating providers with confirmed AF will be managed per their provider's respective assignment. The targeted primary clinical outcome is a reduction in the composite of unplanned cardiovascular (CV) or major bleeding hospitalizations and AF-related emergency department visits. Secondary clinical outcomes, process of care, patient and provider satisfaction as well as economic costs at the system and patient levels are being examined. The trial is anticipated to report in 2018.

Trends in warfarin use and its associations with thromboembolic and bleeding rates in a population with atrial fibrillation between 1996 and 2011

AIM

Warfarin is a cornerstone for the prevention of thromboembolism in atrial fibrillation (AF), and several efforts have been taken to increase its usage and safety, including risk stratification schemes. Our aim was to investigate the temporal trends in initiation of warfarin and its effects on incidence of bleeding and thromboembolism in patients with new-onset atrial fibrillation 1996-2011.

METHODS

All patients with a first-time diagnosis of non-valvular atrial fibrillation were identified from nationwide administrative registries. Trends were determined by linear regression.

RESULTS

In total 153,682 patients were included. Initiation of warfarin increased from 14% to 41% (p<0.0001). Events of thromboembolism decreased from 3.9% to 2.6% annually (p<0.0001). The greatest decline in thromboembolic events was observed for patients with a CHA2DS2VASc score >1, where the annual decline was -0.12% (95%CI: -0.161; -0.084)) for those treated with warfarin and -0.073% (95%CI: -0.116;-0.030)) for those not treated with warfarin. Bleeding increased from 3.3% to 3.9% (p = 0.043). For those with a CHA2DS2VASc score >1 annual bleeding rates increased by 0.095% (95%CI: -0.025; -0.165) in warfarin treated and by 0.056% (95%CI: -0.013; -0.100) in patients not treated with warfarin.

CONCLUSION

Warfarin use increased by nearly a 3-fold between 1996 and 2011. During the same period, thromboembolic events declined by a third and bleeding increased by a fifth, suggesting a beneficial effect associated with higher warfarin use. Notably, a small decline in thromboembolic events and increase in bleeding events was observed for the untreated population, suggesting a changing risk profile of AF patients.

Evaluating the potential for pharmacists to prescribe oral anticoagulants for atrial fibrillation

Background

Oral anticoagulant therapy (OAC) to prevent atrial fibrillation (AF)-related strokes remains poorly used. Alternate strategies, such as community pharmacist prescribing of OAC, should be explored.

Methods

Approximately 400 pharmacists, half with additional prescribing authority (APA), randomly selected from the Alberta College of Pharmacists, were invited to participate in an online survey over a 6-week period. The survey consisted of demographics, case scenarios assessing appropriateness of OAC (based on the 2014 Canadian Cardiovascular Society AF guidelines) and perceived barriers to prescribing. Regression analysis was performed to determine predictors of knowledge.

Results

A total of 35% (139/397) of pharmacists responded to the survey, and 57% of these had APA. Depending on the case scenario, 55% to 92% of pharmacists correctly identified patients eligible for stroke prevention therapy, but only about a half selected the appropriate antithrombotic agent; there was no difference in the knowledge according to APA status. In multivariable analysis, predictors significantly associated with guideline-concordant prescribing were having the pharmacist interact as part of an interprofessional team (p = 0.04) and direct OAC (DOAC) self-efficacy (confidence in ability to extend, adapt, initiate or alter prescriptions; p = 0.02). Barriers to prescribing OAC for APA pharmacists included a lack of AF and DOAC knowledge and preference for consulting the physician first, but these same pharmacists also identified difficulty in contacting the physician as a major barrier.

Interpretation and Conclusion

Community pharmacists can identify patients who would benefit from stroke prevention therapy in AF. However, physician collaboration and further training on AF and guidelines for prescribing OAC are needed.

Temporal Trends in the Use and Comparative Effectiveness of Direct Oral Anticoagulant Agents Versus Warfarin for Nonvalvular Atrial Fibrillation: A Canadian Population-Based Study

BACKGROUND

Direct oral anticoagulants (DOACs) are noninferior to warfarin for stroke prevention in atrial fibrillation (AF). We aimed to determine the population risk of stroke and death in incident AF, stratified by anticoagulation status and type, and the temporal trends of oral anticoagulation practice in the post-DOAC approval period.

METHODS AND RESULTS

We conducted a population-based cohort study of incident nonvalvular AF cases using administrative health data in Alberta, Canada. We used Cox proportional hazards modeling with anticoagulation status as a time-varying exposure and adjusted for age (continuous), sex, congestive heart failure, hypertension, diabetes mellitus, prior transient ischemic attack or ischemic stroke, myocardial infarction, peripheral artery disease, and chronic kidney disease. Primary outcome was the composite of stroke and death. Among 34 965 patients with incident AF (56.0% male, median age 73 years), relative to warfarin, DOAC use was associated with decreased risk of all stroke and death (hazard ratio: 0.90; 95% confidence interval, 0.83-0.97) and decreased hemorrhagic stroke (hazard ratio: 0.60; 95% confidence interval, 0.40-0.91]) but a similar risk of ischemic stroke (hazard ratio: 1.12; 95% confidence interval, 0.94-1.34]). During this time period, DOAC use increased rapidly, surpassing warfarin, but the total oral anticoagulation use in the population remained stable, even in the subgroup with the highest thromboembolic risk.

CONCLUSIONS

In a real-world population-based study of patients with incident AF, anticoagulation with DOACs was associated with decreased risk of stroke and death compared with warfarin. Despite a rapid uptake of DOACs in clinical practice, the total proportion of AF patients on anticoagulation has remained stable, even in high-risk patients.

Bleeding-related admissions in patients with atrial fibrillation receiving antithrombotic therapy: results from the Tasmanian Atrial Fibrillation (TAF) study

PURPOSE

Limited data are available from the Australian setting regarding bleeding in patients with atrial fibrillation (AF) receiving antithrombotic therapy. We aimed to investigate the incidence of hospital admissions due to bleeding and factors associated with bleeding in patients with AF who received antithrombotic therapy.

METHODS

A retrospective cohort study was conducted involving all patients with AF admitted to the Royal Hobart Hospital, Tasmania, Australia, between January 2011 and July 2015. Bleeding rates were calculated per 100 patient-years (PY) of follow-up, and multivariable modelling was used to identify predictors of bleeding.

RESULTS

Of 2202 patients receiving antithrombotic therapy, 113 presented to the hospital with a major or minor bleeding event. These patients were older, had higher stroke and bleeding risk scores and were more often treated with warfarin and multiple antithrombotic therapies than patients who did not experience bleeding. The combined incidence of major and minor bleeding was significantly higher in warfarin- versus direct-acting oral anticoagulants (DOAC)- and antiplatelet-treated patients (4.1 vs 3.0 vs 1.2 per 100 PY, respectively; p = 0.002). Similarly, the rate of major bleeding was higher in patients who received warfarin than in the DOAC and antiplatelet cohorts (2.4 vs 0.4 vs 0.6 per 100 PY, respectively; p = 0.001). In multivariate analysis, increasing age, prior bleeding, warfarin and multiple antithrombotic therapies were independently associated with bleeding.

CONCLUSION

The overall rate of bleeding in this cohort was low relative to similar observational studies. The rate of major bleeding was higher in patients prescribed warfarin compared to DOACs, with a similar rate of major bleeding for DOACs and antiplatelet agents. Our findings suggest potential to strategies to reduce bleeding include using DOACs in preference to warfarin, and avoiding multiple antithrombotic therapies in patients with AF.

Occurrence of death and stroke in patients in 47 countries 1 year after presenting with atrial fibrillation: a cohort study

BACKGROUND

Atrial fibrillation is an important cause of morbidity and mortality worldwide, but scant data are available for long-term outcomes in individuals outside North America or Europe, especially in primary care settings.

METHODS

We did a cohort study using a prospective registry of patients in 47 countries who presented to a hospital emergency department with atrial fibrillation or atrial flutter as a primary or secondary diagnosis. 15 400 individuals were enrolled to determine the occurrence of death and strokes (the primary outcomes) in this cohort over eight geographical regions (North America, western Europe, and Australia; South America; eastern Europe; the Middle East and Mediterranean crescent; sub-Saharan Africa; India; China; and southeast Asia) 1 year after attending the emergency department. Patients from North America, western Europe, and Australia were used as the reference population, and compared with patients from the other seven regions

FINDINGS

Between Dec 24, 2007, and Oct 21, 2011, we enrolled 15 400 individuals to the registry. Follow-up was complete for 15 361 (99·7%), of whom 1758 (11%) died within 1 year. Fewer deaths occurred among patients presenting to the emergency department with a primary diagnosis of atrial fibrillation compared with patients who had atrial fibrillation as a secondary diagnosis (377 [6%] of 6825 patients vs 1381 [16%] of 8536, p<0·0001). Twice as many patients had died by 1 year in South America (192 [17%] of 1132) and Africa (225 [20%] of 1137) compared with North America, western Europe, and Australia (366 [10%] of 3800, p<0·0001). Heart failure was the most common cause of death (519 [30%] of 1758); stroke caused 148 (8%) deaths. 604 (4%) of 15361 patients had had a stroke by 1 year; 170 (3%) of 6825 for whom atrial fibrillation was a primary diagnosis and 434 (5%) of 8536 for whom it was a secondary diagnosis (p<0·0001). The highest number of strokes occurred in patients in Africa (89 [8%] of 1137), China (143 [7%] of 2023), and southeast Asia (88 [7%] of 1331) and the lowest occurred in India (20 [<1%] of 2536). 94 (3%) of 3800 patients in North America, western Europe, and Australia had a stroke.

INTERPRETATION

Marked unexplained inter-regional variations in the occurrence of stroke and mortality suggest that factors other than clinical variables might be important. Prevention of death from heart failure should be a major priority in the treatment of atrial fibrillation.

FUNDING

Boehringer Ingelheim.

Effect of prestroke antiplatelets use on first-ever ischaemic stroke severity and early outcome

OBJECTIVES

We aimed to investigate whether prior use of antiplatelet agents (AP) may be associated with lower severity and improved short-term outcome of the first-ever acute ischaemic stroke.

METHODS

This was a retrospective, case-control study based on a prospective hospital stroke registry covering consecutive acute stroke patients admitted to a single stroke centre in highly urbanised area (Warsaw, Poland) between 1995 and 2013. Patients receiving oral anticoagulants were excluded from the analysis. Statistical analysis included multiple regression and logistic regression adjusted for age, sex, hypertension, atrial fibrillation, congestive heart failure, diabetes, coronary heart disease and history of myocardial infarction.

RESULTS

During the study period, there were 3036 eligible patients, of whom 879 (29%) received AP before stroke onset. Patients from the AP group were older and more often burdened with stroke risk factors. There were no differences in baseline stroke severity, hospital mortality and proportion of patients alive and independent at discharge. However, AP turned out to be independently associated with lower NIHSS score on admission (β = -0.045, p = 0.008) and increased odds for being alive and independent at discharge (odds ratio 1.36, 95% CI: 1.13-1.67) and decreased odds for in-hospital mortality (odds ratio 0.77, 95% CI: 0.59-0.99).

CONCLUSIONS

Our findings provide further evidence supporting modest benefit of AP therapy on the course and outcome of first-ever ischaemic stroke. Further large studies are needed to confirm this effect.

The Risk of Hospital Admission Due to Traumatic Brain Injury Is Increased in Older Persons With Severe Functional Limitations

INTRODUCTION

Hospital admissions due to traumatic brain injuries (TBIs) in older persons are increasing. Falls are the leading mechanism of injury in this age group. TBIs are associated with unfavorable outcomes such as mortality and institutionalization.

OBJECTIVES

To estimate rates of TBIs in older persons with severe functional limitations, expressed as "care need," living in the community, and in older persons with care need living in nursing homes compared with older persons without care need.

PARTICIPANTS

More than 1.2 million persons aged 65 years and older living in Bavaria, Germany, and insured with one of the largest German health insurances (health care and long-term care insurance).

METHODS

Age-standardized rates were calculated based on hospital claims data and claims data of the long-term care insurance and were compared between groups. The 3 groups were defined by claims data of the long-term care insurance.

RESULTS

TBI in older persons account for 4.8 hospital admissions per 1000 person-years. Overall TBI rates do not differ significantly between men and women. TBI rates are lowest in persons without care need and are highest for older persons living in nursing homes. Their contribution to the overall burden of TBI is lower than their contribution to the burden of fragility fractures.

CONCLUSION

TBIs in older persons are common. Those with severe functional limitations are at increased risk for TBI. Nursing home residents have the highest rates of TBI. Fall prevention programs should seek to prevent not only fragility fractures but also head impact.

Temporal Patterns and Predictors of Rate vs Rhythm Control in Patients Attending a Multidisciplinary Atrial Fibrillation Clinic

BACKGROUND

Contemporary trends in the selection of and persistence with rate vs rhythm control for atrial fibrillation (AF) are not well studied, particularly in the context of multidisciplinary AF clinics.

METHODS

The initial arrhythmia management strategy in 1031 consecutive patients attending a multidisciplinary AF clinic from 2005-2012 was analyzed.

RESULTS

The 397 (38.5%) patients initially treated with rhythm control were younger (57.4 ± 14 years vs 65.6 ± 13 years; P < 0.0001) and more likely to be men (64.5% vs 56.9%; P = 0.019). They also had fewer comorbidities, lower CHADS₂ (Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack) scores, and greater symptom burden. The proportion treated with rhythm control declined from 46.9% in 2005-2006 to 28.4% in 2012 (P for trend < 0.0001). Compared with those initially selecting rate control, patients treated with rhythm control required more frequent clinic encounters (7 [interquartile range {IQR}, 3-12] vs 3 [IQR, 2-7]; P < 0.001) and longer follow-up (266 days [IQR, 84-548 days] vs 99 days [IQR, 0-313 days]; P < 0.001). Younger age, absence of diabetes and sleep apnea, earlier treatment year, higher symptom burden, and rural residence were independently associated with rhythm control. Persistence with the initial treatment strategy was reduced in the rhythm-control group (P = 0.003).

CONCLUSIONS

Use of rhythm control as the initial arrhythmia management strategy for AF in a specialty AF clinic is declining. Rhythm control requires more intensive follow-up and was more likely to lead to a change in arrhythmia management strategy.

Temporal Trends of Digoxin Use in Patients Hospitalized With Heart Failure: Analysis From the American Heart Association Get With The Guidelines-Heart Failure Registry

OBJECTIVES

The aim of this study was to assess temporal trends and factors associated with digoxin use at discharge among patients admitted with heart failure (HF).

BACKGROUND

Digoxin has class IIa recommendations for treating HF with reduced ejection fraction (HFrEF) in the United States. Digoxin use, temporal trends, and clinical characteristics of HF patients in current clinical practice in the United States have not been well studied.

METHODS

An observational analysis of 255,901 patients hospitalized with HF (117,761 with HFrEF and 138,140 with preserved EF [HFpEF]) from 398 hospitals participating in the Get With The Guidelines-HF registry between January 2005 and June 2014 was conducted to assess the temporal trends and factors associated with digoxin use.

RESULTS

Among 117,761 HFrEF patients, only 19.7% received digoxin at discharge. Digoxin prescriptions decreased from 33.1% in 2005 to 10.7% in 2014 (ptrend < 0.0001). Factors associated with digoxin use in HFrEF included atrial fibrillation (AF) (odds ratio [OR]: 2.14; 95% confidence intervals [CI]: 2.02 to 2.28), history of implantable cardioverter defibrillator use (OR: 1.39; 95% CI: 1.32 to 1.46), chronic obstructive pulmonary disease (OR: 1.13, 95% CI: 1.08 to 1.18), diabetes mellitus (OR: 1.10, 95% CI: 1.06 to 1.14), younger age (OR: 0.96, 95% CI: 0.95 to 0.97), lower blood pressure (OR: 0.96, 95% CI: 0.96 to 0.97), and having no history of renal insufficiency (OR: 0.91, 95% CI: 0.85 to 0.97). Use of digoxin in patients with HFpEF (n = 138,140) without AF was 9.8% in 2005, which decreased to 2.2% in 2014 (ptrend < 0.0001).

CONCLUSIONS

One in 5 HFrEF patients received digoxin at discharge, with a significant downward temporal trend in use over the study period. Use of digoxin in HFpEF patients without AF was very low and decreased over the study period.

Impact of Rural Residence on Warfarin Use and Clinical Events in Patients with Non-Valvular Atrial Fibrillation: A Canadian Population Based Study

BACKGROUND AND PURPOSE

We studied whether anticoagulant use and outcomes differed between rural versus urban Canadian non-valvular atrial fibrillation (NVAF) patients prior to the introduction of direct oral anticoagulant drugs.

METHODS

Retrospective cohort study of 25,284 adult Albertans with NVAF between April 1, 1999 and December 31, 2008.

RESULTS

Compared to urban patients, rural patients were older (p = 0.0009) and had more comorbidities but lower bleeding risk at baseline. In the first year after NVAF diagnosis, urban patients were less likely to be hospitalized (aOR 0.82, 95%CI 0.77-0.89) or have an emergency department visit for any reason (aOR 0.61, 95%CI 0.56-0.66) but warfarin dispensation rates (72.2% vs 71.8% at 365 days, p = 0.98) and clinical outcomes were similar: 7.8% died in both groups, 3.2% rural vs. 2.8% urban had a stroke or systemic embolism (SSE) (aOR 0.92, 95%CI 0.77-1.11), and 6.6% vs. 5.7% (aOR 0.93, 95%CI 0.81-1.06) had a bleed. Baseline SSE risk did not impact warfarin dispensation (73.0% in those with high vs. 72.8% in those with low CHADS2 score, p = 0.85) but patients at higher baseline bleeding risk were less likely to be using warfarin (69.2% high vs. 73.6% low HASBLED score, p<0.0001) in the first 365 days after diagnosis. In warfarin users, bleeding was more frequent (7.5% vs 6.2%, aHR 1.51 [95%CI 1.33-1.72]) but death or SSE was less frequent (7.0% vs 18.1%, aHR 0.60 [0.54-0.66]).

CONCLUSION

Warfarin use and clinical event rates did not differ between rural and urban NVAF patients in a universal access publically-funded healthcare system.

Prospective national study of the prevalence, incidence, management and outcome of a large contemporary cohort of patients with incident non-valvular atrial fibrillation

BACKGROUND

There are few studies of atrial fibrillation (AF) outside of North America or Europe. The aim of the present study was to assess the prevalence, incidence, management and outcomes of patients with new atrial fibrillation, in a large contemporary cohort (2004-2012) of adult patients.

METHODS AND RESULTS

The Clalit Health Services (CHS) computerized database of 2 420 000 adults, includes data of community clinic visits, hospital discharge records, medical diagnoses, medications, medical interventions, and laboratory test results. The prevalence of AF on January 1, 2004 was 71 644 (3%). Prevalence and incidence of AF increased with age and was higher in men versus women. During the study period (2004-2012) 98 811 patients developed new non-valvular AF (mean age -72, 50% women, 46% with cardiovascular disease, 6% with prior stroke). The rate of persistent warfarin use (dispensed for >3 months in a calendar year) was low (25.7%) and it increased with increasing stroke risk score. Individual Time in Therapeutic Range (TTR) among warfarin users was 42%. The incidence rate of ischemic stroke and death increased with age. The rate of stroke increased from 2 per 1000 person years in patients with CHA(2)DS(2)_VASC SCORE of 0, to 58 per 1000 person years in those with a score of 9.

CONCLUSIONS

In the present study the prevalence and incidence of AF, stroke, and death were comparable to those reported in Europe and North America. The low use of anticoagulation calls for measures to increase adherence to current treatment recommendations in order to improve outcomes.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

KEY LIMITATIONS

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

CONCLUSIONS

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

Cardiac glycosides use and the risk of lung cancer: a nested case-control study

Background

Two studies have reported statistically significant associations between the use of cardiac glycosides (CGs) and an increased risk of lung cancer. However, these studies had a number of methodological limitations. Thus, the objective of this study was to assess this association in a large population-based cohort of patients.

Methods

We used the United Kingdom Clinical Practice Research Datalink (CPRD) to identify a cohort of patients, at least 40 years of age, newly-diagnosed with heart failure, or supra-ventricular arrhythmia. A nested case–control analysis was conducted where each incident case of lung cancer identified during follow-up was randomly matched with up to 10 controls. Exposure to CGs was assessed in terms of ever use, cumulative duration of use and cumulative dose. Rate ratios (RRs) with 95% confidence intervals (CIs) were estimated using conditional logistic regression after adjusting for potential confounders.

Results

A total of 129,002 patients were included, and followed for a mean (SD) of 4.7 (3.8) years. During follow-up, 1237 patients were newly-diagnosed with lung cancer. Overall, ever use of CGs was not associated with an increased risk of lung cancer when compared to never use (RR = 1.09, 95% CI: 0.94-1.26). In addition, no dose–response relationship was observed in terms of cumulative duration of use and cumulative dose with all RRs around the null value across quartile categories.

Conclusion

The results of this large population-based study indicate that the use of CGs is not associated with an increased risk of lung cancer.

Cardiac glycosides and the risk of breast cancer in women with chronic heart failure and supraventricular arrhythmia

The aim of this study is to determine whether the use of cardiac glycosides (CGs), drugs used in the treatment of congestive heart failure (CHF) and supra-ventricular arrhythmia, is associated with an increased risk of breast cancer. A cohort of 53,454 women newly diagnosed with CHF or supra-ventricular arrhythmia between January 1, 1988 and December 31, 2010, followed until December 31, 2012, was identified using the United Kingdom Clinical Practice Research Datalink. A nested case-control analysis was performed, where all incident cases of breast cancer occurring during follow-up were identified and matched with up to 10 controls on age, cohort entry date, and duration of follow-up. Conditional logistic regression models were used to estimate adjusted odds ratios (ORs) with 95 % confidence intervals (CIs) of incident breast cancer associated with the use of CGs, along with measures of cumulative duration of use and dose. All analyses considered a one year lag period prior to the event, necessary for latency considerations and to minimize detection bias. The 898 breast cancer cases diagnosed beyond one year of follow-up were matched to 8,940 controls. Overall, use of CGs was not associated with an increased risk of breast cancer when compared to non-use (OR 1.07, 95 % CI 0.90-1.26). Furthermore, the risk did not vary with cumulative duration of use or cumulative dose. The findings of this large population-based study indicate that the use of CGs is not associated with an increased risk of breast cancer. This should provide reassurance to physicians and patients using these drugs.

Trends in the pharmacologic management of atrial fibrillation: Data from the Veterans Affairs health system

BACKGROUND

Prescribing rate control medications with or without antiarrhythmic drugs is often the first course treatment for atrial fibrillation (AF). Clinical trial data suggest that antiarrhythmic drugs are only marginally effective and have multiple drawbacks, whereas rate control alone is sufficient for most patients with minimally symptomatic AF. This study investigates changes in the use of oral rate and rhythm control therapy for AF during fiscal years 2002 through 2011 in the US Veterans Affairs (VA) health system.

METHODS

Patients with new AF episodes were identified in Veterans Health Administration administrative data files, and receipt of oral rate- and rhythm-controlling drugs within 90 days of new AF episodes was determined for each patient.

RESULTS

The percentage of patients receiving an oral rate-controlling medication decreased from 74.9% in 2002 through 2003 to 70.9% in 2010 through 2011. The use of digoxin decreased by >50%, whereas the use of β-blockers metoprolol and carvedilol increased. The proportion of patients receiving any oral antiarrhythmic medication decreased from 13.5% in 2002 through 2003 to 11.6% in 2010 through 2011, and use of the most frequently prescribed oral antiarrhythmic, amiodarone, decreased by 17%.

CONCLUSIONS

Rate control remains the dominant strategy for treating new AF. The decrease in the use of oral antiarrhythmics may be due to lack of concrete data suggesting mortality and morbidity benefit as well as increasing use of the ablation approach.

BULLET POINTS

The proportion of patients with new AF episodes who were prescribed oral rate or rhythm control medications decreased modestly from 2002 through 2011. The use of digoxin decreased by >50%, and amiodarone decreased by 17%. Rate control remains the dominant strategy for treating new AF.

Does digoxin increase the risk of ischemic stroke and mortality in atrial fibrillation? A nationwide population-based cohort study

BACKGROUND

Digoxin and related cardiac glycosides have been used for almost 100 years in atrial fibrillation (AF). However, 2 recent analyses of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) trial showed inconsistent results regarding the risk of mortality associated with digoxin use. The goal of the present study was to investigate the relationship between digoxin and the risk of ischemic stroke and mortality in Asians.

METHODS

This study used the National Health Insurance Research Database (NHIRD) in Taiwan. A total of 4781 patients with AF who did not receive any antithrombotic therapy were selected as the study population. Among the study population, 829 participants (17.3%) received the digoxin treatment. The risk of ischemic stroke and mortality in patients who received digoxin and those who did not was compared.

RESULTS

The use of digoxin was associated with an increased risk of clinical events, with an adjusted hazard ratio of 1.41 (95% confidence interval [CI], 1.17-1.70) for ischemic stroke and 1.21 (95% CI, 1.01-1.44) for all-cause mortality. In the subgroup analysis based on coexistence with heart failure or not, digoxin was a risk factor for adverse events in patients without heart failure but not in those with heart failure (interaction P < 0.001 for either end point). Among patients with AF without heart failure, the use of β-blockers was associated with better survival, with an adjusted hazard ratio of 0.48 (95% CI, 0.34-0.68).

CONCLUSIONS

Digoxin should be avoided for patients with AF without heart failure because it was associated with an increased risk of clinical events. β-Blockers may be a better choice for controlling ventricular rate in these patients.

Current Evidence and Recommendations for Rate Control in Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice, which is associated with substantial risk of stroke and thromboembolism. As an arrhythmia that is particularly common in the elderly, it is an important contributor towards morbidity and mortality. Ventricular rate control has been a preferred and therapeutically convenient treatment strategy for the management of AF. Recent research in the field of rhythm control has led to the advent of newer antiarrhythmic drugs and catheter ablation techniques as newer therapeutic options. Currently available antiarrhythmic drugs still remain limited by their suboptimal efficacy and significant adverse effects. Catheter ablation as a newer modality to achieve sinus rhythm (SR) continues to evolve, but data on long-term outcomes on its efficacy and mortality outcomes are not yet available. Despite these current developments, rate control continues to be the front-line treatment strategy, especially in older and minimally symptomatic patients who might not tolerate the antiarrhythmic drug treatment. This review article discusses the current evidence and recommendations for ventricular rate control in the management of AF. We also highlight the considerations for rhythm control strategy in the management of patients of AF.