The prevalence of atrial fibrillation in a geographically well-defined population in northern Sweden: implications for anticoagulation prophylaxis

ANMCO-SIMEU consensus document: appropriate management of atrial fibrillation in the emergency department

Atrial fibrillation (AF) accounts for 2% of the total presentations to the emergency department (ED) and represents the most frequent arrhythmic cause for hospitalization. It steadily increases the risk of thromboembolic events and is often associated with several comorbidities that negatively affect patient's quality of life and prognosis. AF has a considerable impact on healthcare resources, making the promotion of an adequate and coordinated management of this arrhythmia necessary in order to avoid clinical complications and to implement the adoption of appropriate technological and pharmacological treatment options. AF management varies across regions and hospitals and there is also heterogeneity in the use of anticoagulation and electric cardioversion, with limited use of direct oral anticoagulants. The ED represents the first access point for early management of patients with AF. The appropriate management of this arrhythmia in the acute setting has a great impact on improving patient's quality of life and outcomes as well as on rationalization of the financial resources related to the clinical course of AF. Therefore, physicians should provide a well-structured clinical and diagnostic pathway for patients with AF who are admitted to the ED. This should be based on a tight and propositional collaboration among several specialists, i.e. the ED physician, cardiologist, internal medicine physician, anesthesiologist. The aim of this ANMCO-SIMEU consensus document is to provide shared recommendations for promoting an integrated, accurate, and up-to-date management of patients with AF admitted to the ED or Cardiology Department, in order to make it homogeneous across the national territory.

World Heart Federation Roadmap on Atrial Fibrillation - A 2020 Update

The World Heart Federation (WHF) commenced a Roadmap initiative in 2015 to reduce the global burden of cardiovascular disease and resultant burgeoning of healthcare costs. Roadmaps provide a blueprint for implementation of priority solutions for the principal cardiovascular diseases leading to death and disability. Atrial fibrillation (AF) is one of these conditions and is an increasing problem due to ageing of the world's population and an increase in cardiovascular risk factors that predispose to AF. The goal of the AF roadmap was to provide guidance on priority interventions that are feasible in multiple countries, and to identify roadblocks and potential strategies to overcome them. Since publication of the AF Roadmap in 2017, there have been many technological advances including devices and artificial intelligence for identification and prediction of unknown AF, better methods to achieve rhythm control, and widespread uptake of smartphones and apps that could facilitate new approaches to healthcare delivery and increasing community AF awareness. In addition, the World Health Organisation added the non-vitamin K antagonist oral anticoagulants (NOACs) to the Essential Medicines List, making it possible to increase advocacy for their widespread adoption as therapy to prevent stroke. These advances motivated the WHF to commission a 2020 AF Roadmap update. Three years after the original Roadmap publication, the identified barriers and solutions were judged still relevant, and progress has been slow. This 2020 Roadmap update reviews the significant changes since 2017 and identifies priority areas for achieving the goals of reducing death and disability related to AF, particularly targeted at low-middle income countries. These include advocacy to increase appreciation of the scope of the problem; plugging gaps in guideline management and prevention through physician education, increasing patient health literacy, and novel ways to increase access to integrated healthcare including mHealth and digital transformations; and greater emphasis on achieving practical solutions to national and regional entrenched barriers. Despite the advances reviewed in this update, the task will not be easy, but the health rewards of implementing solutions that are both innovative and practical will be great.

Validation of an algorithm based on administrative data to detect new onset of atrial fibrillation after cardiac surgery

Introduction

Postoperative atrial fibrillation (POAF) is a frequent complication of cardiac surgery associated with important morbidity, mortality, and costs. To assess the effectiveness of preventive interventions, an important prerequisite is to have access to accurate measures of POAF incidence. The aim of this study was to develop and validate such a measure.

Methods

A validation study was conducted at two large Canadian university health centers. First, a random sample of 976 (10.4%) patients who had cardiac surgery at these sites between 2010 and 2016 was generated. Then, a reference standard assessment of their medical records was performed to determine their true POAF status on discharge (positive/negative). The accuracy of various algorithms combining diagnostic and procedure codes from: 1) the current hospitalization, and 2) hospitalizations up to 6 years before the current hospitalization was assessed in comparison with the reference standard. Overall and site-specific estimates of sensitivity, specificity, positive (PPV), and negative (NPV) predictive values were generated, along with their 95%CIs.

Results

Upon manual review, 324 (33.2%) patients were POAF-positive. Our best-performing algorithm combining data from both sites used a look-back window of 6 years to exclude patients previously known for AF. This algorithm achieved 70.4% sensitivity (95%CI: 65.1–75.3), 86.0% specificity (95%CI: 83.1–88.6), 71.5% PPV (95%CI: 66.2–76.4), and 85.4% NPV (95%CI: 82.5–88.0). However, significant site-specific differences in sensitivity and NPV were observed.

Conclusion

An algorithm based on administrative data can identify POAF patients with moderate accuracy. However, site-specific variations in coding practices have significant impact on accuracy.

Burden of atrial fibrillation and stroke risk among octagenarian and nonagenarian women in Australia

PURPOSE

To determine the prevalence and incidence of atrial fibrillation (AF) among older Australian women from 2000 to 2015, determine factors associated with AF, and to calculate risk of stroke at the time of AF diagnosis.

METHODS

This is a retrospective analysis of 6671 women of the 1921-1926 birth cohort of the Australian Longitudinal Study on Women's Health, linked to data from hospital admissions to identify AF and National Death Index to determine date of death. Yearly prevalence and incidence proportions of AF, and stroke risk using CHA2DS2-VA scheme, were calculated. Factors associated with AF were assessed using logistic regression.

RESULTS

From 2000 to 2015, a total of 1827 women with AF were identified. AF prevalence increased every year as women aged from 2.71% (95% CI 1.62%-3.80%) in 2000 among women aged 74-79 years to 24.83% (95% CI = 23.23%-26.44%) in 2015 among women aged 89-94 years. The incidence proportion remained constant (between 3% and 5%) throughout the study period. Sedentary lifestyle (OR = 1.24, 95% CI = 1.04-1.49), hypertension (OR = 1.24, 95% CI = 1.09-1.42), arthritis (OR = 1.24, 95% CI = 1.09-1.41), heart attack (OR = 1.62, 95% CI = 1.18-2.24), and angina (OR = 1.39, 95% CI = 1.14-1.70) were independently associated with AF. Mean CHA2DS2-VA score for women with AF was 3.43 (SD ± 1.23).

CONCLUSIONS

The prevalence of AF reported in Australian women is among the highest compared to previous estimations from other countries and regions. According to the findings, about one in four women over the age of 90 years had AF. These women were also at high risk of stroke. This has significant public health implications especially with changing demographics of increase in the aging population. Further research is required on understanding how women with AF are treated in Australia and their health outcomes.

Atrial fibrillation in the elderly general population: a 30-year follow-up from 70 to 100 years of age

Objectives. There is limited knowledge of atrial fibrillation (AF) incidence among the very old. Data from longitudinal cohort studies may give us a better insight. The aim of the study was to investigate the incidence rate and prevalence of AF, as well as the impact of AF on mortality, in the general population, from 70 to 100 years of age. Design. This was a population-based prospective cohort study where three representative samples of 70-year-old men and women (n = 2,629) from the Gerontological and Geriatric Populations Studies in Gothenburg (H-70) were included between 1971 and 1982. The participants were examined at age 70 years and were re-examined repeatedly until 100 years of age. AF was diagnosed according to a 12-lead electrocardiogram (ECG) recording at baseline and follow-up examinations, from the Swedish National Patient Register (NPR), or from the Cause of Death Register. Results. The cumulative incidence of AF from 70 to 100 years of age was 65.6% for men and 52.8% for women. Mortality was significantly higher in participants with AF compared with those without, rate ratio (RR) 1.92 (95% CI 1.73-2.14). In a subgroup analysis comprising only participants with AF diagnosed by ECG at screening, the RR for death was 1.29 (95% C.I: 1.03-1.63). Conclusions. Among persons surviving to age 70, the cumulative incidence of AF was over 50% during follow-up. Mortality rate was twice as high in participants with AF compared to participants without AF. Among participants with AF first recorded at a screening examination, the increased risk was only 29%.

Prevalence and Incidence of Atrial Fibrillation and Other Arrhythmias in the General Older Population: Findings From the Swedish National Study on Aging and Care

Aim: To study the prevalence and cumulative incidence of arrhythmias in the general population of adults aged 60 and older over a 6-year period. Study Design and Setting: Data were taken from the Swedish National Study on Aging and Care (SNAC), a national, longitudinal, multidisciplinary study of the general elderly population (defined as 60 years of age or older). A 12-lead resting electrocardiography (ECG) was performed at baseline and 6-year follow-up. Results: The baseline prevalence of atrial fibrillation (AF) was 4.9% (95% confidence interval [CI] = [4.5%, 5.5%]), and other arrhythmias including ventricular premature complexes (VPCs), supraventricular tachycardia (SVT), and supraventricular extrasystole (SVES) were seen in 8.4% (7.7%, 9.0%) of the population. A first- or second-degree atrioventricular (AV) block was found in 7.1% of the population (95% CI = [6.5%, 7.7%]), and there were no significant differences between men and women in baseline arrhythmia prevalence. The 6-year cumulative incidence of AF was 4.1% (95% CI = [3.5%, 4.9%]), or 6.9/1,000 person-years (py; 95% CI = [5.7, 8.0]). The incidence of AF, other arrhythmias, AV block, and pacemaker-induced rhythm was significantly higher in men in all cohorts except for the oldest. Conclusion: Our data highlight the prevalence and incidence of arrhythmias, which rapidly increase with advancing age in the general population.

Prevalence of atrial fibrillation in the Italian elderly population and projections from 2020 to 2060 for Italy and the European Union: the FAI Project

Aims

To estimate prevalence of atrial fibrillation (AF) in a representative sample of the Italian elderly population, projecting figures for Italy and the European Union.

Methods and results

A cross-sectional examination of all subjects aged 65+ years from three general practices in Northern, Central, and Southern Italy started in 2016. Participants were administered a systematic and an opportunistic screening, followed by clinical and electrocardiogram confirmation. The study sample included 6016 subjects. Excluding 235 non-eligible, among the remaining 5781 participation was 78.3%, which left 4528 participants (mean age 74.5 ± 6.8 years, 47.2% men). Prevalence of AF was 7.3% [95% confidence intervals (CI) 6.6–8.1], higher in men and with advancing age (6.6% from systematic plus 0.7% from opportunistic screening). Using prevalence figures, Italian elderly having AF in 2016 were estimated at ∼1 081 000 (95% CI 786 000–1 482 000). Considering stable prevalence, this number will increase by 75% to ∼1 892 000 in 2060 (95% CI 1 378 000–2 579 000). European Union elderly having AF in 2016 were estimated at ∼7 617 000 (95% CI 5 530 000–10 460 000), increasing by 89% to ∼14 401 000 in 2060 (95% CI 10 489 000–19 647 000). In 2016, subjects aged 80+ years represented 53.5% of cases in Italy and 51.2% in the European Union; in 2060, 69.6% and 65.2%, respectively.

Conclusions

Our findings indicate a high burden of AF in coming decades, especially among the oldest-old, who carry the higher AF-related risk of stroke and medical complications.

Prevalence of atrial fibrillation and cardiovascular risk factors in a 63-65 years old general population cohort: the Akershus Cardiac Examination (ACE) 1950 Study

OBJECTIVES

To investigate the sex-specific prevalence of atrial fibrillation (AF), including subclinical AF found by screening in a general population aged 63-65 years. The prevalence of cardiovascular risk factors and their association with AF will also be investigated.

DESIGN

Cross-sectional analysis of an observational, prospective, longitudinal, population-based cohort study.

SETTING

General population in Akershus county, Norway.

PARTICIPANTS

Women and men born in 1950. We included 3706 of 5827 eligible individuals (63.6%); 48.8% were women.

METHODS

All participants underwent extensive cardiovascular examinations, including 12-lead ECG. History of AF and other cardiovascular diseases were self-reported. Subsequent validation of all reported or detected AF diagnoses was performed.

RESULTS

Mean age was 63.9±0.7 years. Prevalence of ECG-verified AF was 4.5% (women 2.4%, men 6.4%; p<0.001), including screen-detected AF in 0.3% (women 0.1%, men 0.6%; p<0.01). Hypertension was found in 62.0% (women 57.8%, men 66.0%; p<0.001). Overweight or obesity was found in 67.6% (women 59.8%, men 74.9%; p<0.001). By multivariate logistic regression, risk factors associated with AF were height (OR 1.67 per 10 cm; 95% CI 1.26 to 2.22; p<0.001), weight (OR 1.15 per 10 kg; 95% CI 1.01 to 1.30; p=0.03), hypertension (OR 2.49; 95% CI 1.61 to 3.86; p<0.001), heart failure (OR 3.51; 95% CI 1.71 to 7.24; p=0.001), reduced estimated glomerular filtration rate (OR 2.56; 95% CI 1.42 to 4.60; p<0.01) and at least one first-degree relative with AF (OR 2.32; 95% CI 1.63 to 3.31; p<0.001), whereas male sex was not significantly associated (OR 1.00; 95% CI 0.59 to 1.68; p=0.99).

CONCLUSION

In this cohort from the general population aged 63-65 years, we found a higher prevalence of known AF than previously reported below the age of 65 years. The additional yield of single time point screening for AF was low. Body size and comorbidity may explain most of the sex difference in AF prevalence at this age.

TRIAL REGISTRATION NUMBER

NCT01555411; Results.

Diagnostic accuracy and yield of screening tests for atrial fibrillation in the family practice setting: a multicentre cohort study

BACKGROUND

Detection of undiagnosed or undertreated ("actionable") atrial fibrillation could increase the use of appropriate oral anticoagulant therapy and reduce the risk of stroke. We sought to compare newer screening technologies with a pulse-check for the detection of atrial fibrillation and to determine whether the detection of actionable atrial fibrillation increases the use of oral anticoagulant agents.

METHODS

This prospective multicentre cohort study involved 22 primary care clinics. We recruited participants aged 65 years and older who were attending routine appointments. Each participant underwent 3 methods of screening: a 30-second radial pulse-check; single-lead electrocardiogram; and screening by blood pressure machine with atrial fibrillation detection algorithms. Participants who received a positive result on 1 or more test underwent 12-lead electrocardiogram with or withour 24-hour Holter. Screening tests were compared using the McNemar test. Participants with confirmed atrial fibrillation received follow-up at 90 days.

RESULTS

The mean age of participants was 73.7 (± 6.9) years, and 53.4% of participants were female. Of 2171 patients, we had data from all 3 screening tests for 2054 patients. Both single-lead electrocardiogram and the blood pressure device showed superior specificity compared with pulse-check (p < 0.001 for each). Fifty-six patients (2.7%) had confirmed atrial fibrillation: 12 patients had newly detected atrial fibrillation (none of the patients were using anticoagulation agents), and 44 patients had previously diagnosed atrial fibrillation (42 patients were receiving anticoagulant therapy, 2 were not). Thus, 14 patients had actionable atrial fibrillation (0.7%). By 90 days, 77% of patients with actionable atrial fibrillation had started anticoagulant therapy.

INTERPRETATION

Newer screening technologies showed superior specificity compared with a pulse-check. Screening detected undiagnosed or undertreated atrial fibrillation in 0.7% of participants, and 77% started appropriate anticoagulant therapy.

TRIAL REGISTRATION

ClinicalTrials.gov, no. NCT02262351.

Trends in stroke subtypes and vascular risk factors in a stroke center in China over 10 years

Rapid economic development in China has caused marked changes in people’s lifestyles and medical technology. Exploration of stroke subtype trends is necessary to provide physicians with vital insight for early diagnosis and treatment. We included stroke patients admitted from 2006 to 2015. Trends in stroke subtypes and vascular risk factors were investigated. There were 5521 patients, including 4534 (82.1%) ischemic stroke (IS), 813 (14.7%) intracerebral hemorrhage (ICH) and 174 (3.2%) subarachnoid hemorrhage (SAH) patients. The proportion of IS was increasing and proportions of ICH and SAH were decreasing (P < 0.001). Onset age and hypertension remained stable in stroke subtypes. In IS patients, large artery atherosclerosis (LAA) strokes increased from 17.0% to 30.8% in the first 7 years and ultimately decreased to 24.1%. Small vessel disease (SVD) strokes increased from 15.5% to 39.6%, undetermined etiology (UE) strokes decreased from 52.7% to 26.0%, others remained stable. The levels of low-density lipoprotein declined significantly, and an increased number of patients underwent intracranial artery examinations (P < 0.001). In conclusion, proportions of stroke subtypes changed significantly. Anti-hypertension therapy needs to be reinforced to control ICH, SAH and SVD ischemic stroke incidences. The etiologic detection of IS increased and lipid-lowing therapy was effective, cardioembolism detections should be reinforced.

Cardioversion of atrial fibrillation does not affect obstructive sleep apnea

BACKGROUND

Sleep apnea is common in patients with atrial fibrillation, but the effect of the cardioversion of atrial fibrillation to sinus rhythm on central and obstructive apneas is mainly unknown. The primary aim of the study was to analyze the association between cardioversion of atrial fibrillation and sleep apneas, to investigate whether obstructive or central sleep apneas are reduced following cardioversion. A secondary objective was to study the effect on sleep quality.

METHODS

Twenty-three patients with atrial fibrillation were investigated using overnight polysomnography, including esophagus pressure monitoring and ECG, before and after the cardioversion of persistent atrial fibrillation.

RESULTS

Obstructive sleep apnea occurred in 17/23 patients (74%), and central sleep apnea in 6/23 patients (26%). Five patients had both obstructive and central sleep apnea. Sinus rhythm at follow-up was achieved in 16 patients. The obstructive apnea-hypopnea index, central apnea-hypopnea index, and the number of patients with obstructive or central sleep apnea did not differ before and after restoration of sinus rhythm. Sleep time, sleep efficiency, time in different sleep stages, and subjective daytime sleepiness were normal and unaffected by cardioversion.

CONCLUSIONS

Both obstructive and central sleep apneas are highly prevalent in patients with persistent atrial fibrillation. Obstructive sleep apneas are unaffected by the cardioversion of atrial fibrillation to sinus rhythm. The sleep pattern is normal and unaffected by cardioversion in patients with atrial fibrillation.

CLINICAL TRIAL REGISTRATION

Trial number NCT00429884.

European Society of Cardiology Guideline-Adherent Antithrombotic Treatment and Risk of Mortality in Asian Patients with Atrial Fibrillation

This study compared the risk of mortality in atrial fibrillation (AF) patients treated adherent to the 2012 European Society of Cardiology (ESC) guidelines for stroke prevention and those who were not treated according to guideline recommendations. This study used the Taiwan National Health Insurance Research Database. From 1996 to 2011, 354,649 newly diagnosed AF patients were identified as the study population. Among the study cohort, 45,595 and 309,054 patients were defined as Guideline-Adherent and Non-Adherent groups, respectively. During the follow up of 1,480,280 person-years, 133,552 (37.7%) patients experienced mortality. The risk of mortality was lower among AF patients whose treatment was adherent to the guideline recommendation for stroke prevention than those whose treatment was not (annual risk of mortality = 4.3% versus 10.0%) with an adjusted hazard ratio of 0.62 (95% confidence interval = 0.61–0.64, p value < 0.001) after adjusting for age, gender, CHA₂DS₂-VASc score and antiplatelet therapy. The findings were consistently observed after propensity matching analysis. In conclusion, the risk of mortality was lower for AF patients who were treated according to the antithrombotic recommendations of the 2012 ESC guidelines, guided by the CHA₂DS₂-VASc score. Better efforts to implement guidelines would lead to improved outcomes for patients with AF.

The changing circumstance of atrial fibrillation - progress towards precision medicine

The prevalence of atrial fibrillation (AF) in the general population is between 1% and 2% in the developed world and is higher in men than in women. The arrhythmia occurs much more commonly in the elderly, and the estimated lifetime risk of developing AF is one in four for men and women aged 40 years and above. Projected data from multiple population-based studies in the USA and Europe predict a two- to threefold increase in the number of AF patients by 2060. The high lifetime risk of AF and increased longevity underscore the important public health burden posed by this arrhythmia worldwide. AF has multiple aetiologies and a broad variety of presentations. The primary pathologies underlying or promoting the occurrence of AF vary more than for any other cardiac arrhythmia, ranging from autonomic imbalance to organic heart disease and metabolic disorders, such as diabetes mellitus, metabolic syndrome, hyperthyroidism and kidney disease, and lifestyle factors such as smoking, alcohol consumption and participation in endurance sports. Biomarkers are increasingly being investigated and, together with clinical and genetic factors, will eventually lead to a clinically valuable detailed classification of AF which will also incorporate pathophysiological determinants and mechanisms of the arrhythmia. In turn, this will allow the development and application of precision medicine to this troublesome arrhythmia.

Treatment with oral anticoagulant drugs restrained from patients with atrial fibrillation: An assessment in a geographically well-defined catchment area

BACKGROUND

Atrial fibrillation (AF) affects about 3.2% of the adult population in the western world and incurs an annual stroke risk of 4.5%. The use of oral anticoagulant (OAC) drugs significantly reduces this risk. OAC drugs seem to be under-utilized, but little is known about why their use is restrained in routine clinical management. The aim of this study was to assess this issue and, from these data, to estimate the proportion of patients with AF in a general population who were eligible for treatment with OAC drugs.

DESIGN

Retrospective study of medical records.

METHODS

The study included all identified patients with AF in a well-defined catchment area of 65,532 people, among whom 1616 (3.2%) had documented AF. Of the patients with AF, 588 (36%) were originally reported not to be receiving OAC drugs. The patient-responsible physicians (n = 24) were requested to complete a standardized questionnaire to assess the reason for restraining the use of OAC drugs for each individual patient.

RESULTS

Of the 588 patients originally reported not to be receiving OAC drugs, eight were shown to be using OAC drugs and seven were lost to follow up. Thus the reason for restraining OAC drugs was finally assessed in 573 patients. The primary reasons were: lack of indication, 26%; declined general condition, 14%; a history of bleeding, 12%; assumed poor compliance, 11%; repeated falls, 6%; and reason unknown, 9%.

CONCLUSIONS

This is, to our knowledge, the first study to assess the reasons for restraining the use of OAC drugs in a geographically well-defined population including all hospital-based and non-hospital-based healthcare. Applying CHA2DS2-VASc and new strategies for OAC drugs to our study data indicated that between 72 and 88% of all patients with AF are eligible for treatment with OAC drugs.

Time Trends of Aspirin and Warfarin Use on Stroke and Bleeding Events in Chinese Patients With New-Onset Atrial Fibrillation

BACKGROUND

Much of the clinical epidemiology and treatment patterns for patients with atrial fibrillation (AF) are derived from Western populations. Limited data are available on antithrombotic therapy use over time and its impact on the stroke or bleeding events in newly diagnosed Chinese patients with AF. The present study investigates time trends in warfarin and aspirin use in China in relation to stroke and bleeding events in a Chinese population.

METHODS

We used a medical insurance database involving > 10 million individuals for the years 2001 to 2012 in Yunnan, a southwestern province of China, and performed time-trend analysis on those with newly diagnosed AF. Cox proportional hazards time-varying exposures were used to determine the risk of stroke or bleeding events associated with antithrombotic therapy among patients with AF.

RESULTS

Among the randomly sampled 471,446 participants, there were 1,237 patients with AF, including 921 newly diagnosed with AF, thus providing 4,859 person-years of experience (62% men; mean attained age, 70 years). The overall rate of antithrombotic therapy was 37.7% (347 of 921 patients), with 4.1% (38 of 921) on warfarin and 32.3% (298 of 921) on aspirin. Antithrombotic therapy was not related to stroke/bleeding risk scores (CHADS2 [congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke (doubled)] score, P = .522; CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 75 years (doubled), diabetes mellitus, stroke or transient ischemic attack (doubled), vascular disease, age 65 to 74 years, and female sex] score, P = .957; HAS-BLED [hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly (> 65 years), drugs/alcohol concomitantly] score, P = .095). The use of antithrombotic drugs (mainly aspirin) increased in both women and men over time, with the rate of aspirin increasing from 4.0% in 2007 to 46.1% in 2012 in the former, and from 7.7% in 2007 to 61.9% in 2012 in the latter (P for trend for both, < .005). In the overall cohort, the annual stroke rate was approximately 6% and the annual major bleeding rate was about 1%. Compared with nonantithrombotic therapy, the hazard ratio for ischemic stroke was 0.68 (95% CI, 0.39-1.18) for aspirin and 1.39 (0.54-3.59) for warfarin.

CONCLUSIONS

Aspirin use increased among Chinese patients newly diagnosed with AF, with no relationship to the patient's stroke or bleeding risk. Warfarin use was very low. Given the health-care burden of AF and its complications, our study has major implications for health-care systems in non-Western countries, given the global burden of this common arrhythmia.

The prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population: a prospective study

Background

There is limited information on prevalent and incident atrial fibrillation in Chinese. We aimed to investigate the prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population.

Methods

In a population—based prospective study in elderly (≥60 years) Chinese, we performed cardiovascular health examinations including a 12-lead electrocardiogram at baseline in 3,922 participants and biennially during follow-up in 2,017 participants. We collected information on vital status during the whole follow-up period.

Results

The baseline prevalence of atrial fibrillation was 2.0 % (n = 34) in 1718 men and 1.6 % (n = 36) in 2204 women. During a median 3.8 years of follow-up, the incidence rate of atrial fibrillation (n = 34) was 4.9 per 1000 person-years (95 % confidence interval [CI], 3.4–6.9). In univariate analysis, both the prevalence and incidence of atrial fibrillation were higher with age advancing (P < 0.0001) and in the presence of coronary heart disease (P ≤ 0.02). Of the 104 prevalent and incident cases of atrial fibrillation, only 1 (1.0 %) received anticoagulant therapy (warfarin). These patients with atrial fibrillation, compared with those with sinus rhythm, had significantly higher risks of all-cause (n = 261, hazard ratio [HR] 1.87, 95 % CI, 1.09–3.20, P = 0.02), cardiovascular (n = 136, HR 3.78, 95 % CI 2.17–6.58, P < 0.0001) and stroke mortality (n = 44, HR 6.31, 95 % CI 2.81–14.19, P = 0.0003).

Conclusions

Atrial fibrillation was relatively frequent in elderly Chinese, poorly managed and associated with higher risks of mortality.

Prevalence, incidence, and lifetime risk of atrial fibrillation in China: new insights into the global burden of atrial fibrillation

BACKGROUND

Much of the epidemiology of atrial fibrillation (AF) is based on data from Western populations. Despite the huge population of Asia, data on the clinical epidemiology of AF in Asian countries are limited. The current study aimed to investigate the prevalence and incidence of newly diagnosed (ie, incident) AF, as well as lifetime risk, in China and to determine the clinical risk factors contributing to its development.

METHODS

Using a medical insurance database involving > 10 million individuals for the years 2001 to 2012 in the southwest of China, trends in incident AF were calculated using Kaplan-Meier analysis and Cox regression. The usefulness of the CHADS2 (congestive heart failure, hypertension, age, diabetes, stroke [doubled]) and CHA2DS2-VASc (congestive heart failure, hypertension, age ≥ 75 [doubled], diabetes, stroke [doubled], vascular disease, age 65-74, and sex category [female]) scores was tested in predicting the occurrence of incident AF.

RESULTS

A total of 471,446 individuals (aged ≥ 20 years) were studied, with 1,924,975 person-years of experience. We identified 921 patients with incident AF (62% male; mean age, 62 years). The prevalence of incident AF in subjects aged ≥ 20 years was 0.2 per 100 people, with an incidence of AF of 0.05 per 100 person-years overall. Over an 11-year period, the prevalence of AF increased 20-fold, whereas AF-related stroke increased 13-fold. The lifetime risk of AF was approximately one in five among Chinese adults, and it increased with advancing age. The CHA2DS2-VASc score was superior to the CHADS2 score in predicting the risk of incident AF in our Chinese population (DeLong test, Z = 6.621, P < .001).

CONCLUSIONS

The AF burden, as well as the risk of AF-related stroke, has increased significantly over the past 11 years in the southwest of China. The public health burden of AF and its complications are greatest in the very elderly, with major implications for health-care systems given the global burden of this common arrhythmia.

Characterization of patients with atrial fibrillation not treated with oral anticoagulants

OBJECTIVE

An underuse of oral anticoagulants (OAC) in patients with atrial fibrillation (AF) has been suggested, as only 50% of all patients with AF receive OAC treatment. Whether this is due to contraindications, lack of an indication to treat, or an expression of underuse is sparsely investigated. This study therefore aimed to characterize individuals without OAC treatment in a real-life population of patients with AF.

DESIGN

Retrospective cross-sectional study. The medical records were scrutinized in order to identify the type of AF, risk factors for embolism and bleeding, and other factors of importance for OAC treatment.

SETTING

The municipalities of Skellefteå and Norsjö, northern Sweden.

SUBJECTS

A total of 2274 living residents with at least one verified episode of AF on or before December 31, 2010.

MAIN OUTCOME MEASURES

Prevalence of treatment with OAC and documented reasons to withhold OAC treatment.

RESULTS

Among all 2274 patients with AF, 1187 (52%) were not treated with OAC. Of the untreated patients, 19% had no indication or had declined or had experienced adverse effects other than bleeding on warfarin treatment. The most common reason to withhold OAC was presence of risk factors for bleeding, found in 38% of all untreated patients. Furthermore, a documented reason could be identified to withhold OAC in 75%.

CONCLUSIONS

Among patients with AF without OAC treatment a reason could be identified to withhold OAC in 75%. The underuse of OAC is estimated to be 25%.

Estimating the prevalence of atrial fibrillation in a general population using validated electronic health data

Background

The purpose of this study was to determine the prevalence of atrial fibrillation (AF) in the general population and to validate an administrative diagnosis register, ie, the National Patient Register (NPR), and an electrocardiography (ECG) database in estimating disease prevalence.

Methods

The study was conducted in a well defined region in northern Sweden (population n=75,945) which consists of one hospital and eleven primary health care centers. Subjects with AF were identified by searching the combined inpatient and outpatient International Classification of Diseases (ICD)-based NPR (ICD-10 code I48) and an ECG database with computer-interpreted AF from January 1, 2004 to December 31, 2010. All identified cases with AF were validated.

Results

AF was confirmed in 2,274 patients. The overall prevalence was 3.0% (3.4% in men and 2.6% in women). AF prevalence rose steadily with age, and was 16.8% in patients aged 75 years and older and 21.9% in patients 85 years and older. Of all patients with validated AF, the NPR identified 93.2%. The ECG database identified an additional 6.8%, of which 81% were over 70 years of age. According to the NPR, the proportion of false positives and false negatives was 3.5% and 6.8%, respectively. The corresponding figure for the ECG database was 11.3% and 9.2%, respectively.

Conclusion

Our study shows a high prevalence of AF, especially among the elderly. Searching the ECG database enhanced the detection of AF. The reliability of the NPR was high, with a relatively low proportion of false positives and negatives.

Recommencement of anticoagulation in chronic subdural haematoma: a systematic review and meta-analysis

OBJECTIVE

Chronic subdural haematoma (CSDH) is becoming an increasingly important neurosurgical condition, especially given the aging world population and the increasing use of anticoagulant and antiplatelet medication. Clinicians regularly confront the dilemma of whether or not to restart anticoagulant and antiplatelet medication after CSDH, yet there is little evidence to support the decision-making process. This systematic review and meta-analysis aims to address this specific question.

METHODS

This systematic review and meta-analysis was conducted according to the PRISMA guidelines and has been registered with the PROSPERO international prospective register of systematic reviews (registration number CRD42012002509). Databases including MEDLINE, Cochrane, ISI Web of Knowledge, Embase and Google Scholar were searched for retrospective and prospective studies looking specifically at patients presenting with CSDH whilst on anticoagulant or antiplatelet medication which had data on subsequent recurrence and thromboembolic events.

RESULTS

Three relevant studies were found, totalling to 64 patients. In those restarted on anticoagulation, 11.1% experienced recurrences and 2.2% experienced thromboembolic events. In the control group that was not restarted on anticoagulation, 22.2% experienced recurrences and no patient experienced thromboembolic events. All recurrences and thromboembolic events occurred within the first 4 weeks of the initial surgical evacuation.

CONCLUSIONS

The review seems to paradoxically suggest a lower bleeding risk and a higher thromboembolism risk when anticoagulation is restarted, although few concrete conclusions can be drawn from a pool of 64 patients. The decision on whether or not to restart anticoagulation in patients who present with CSDH whilst on anticoagulation has little empirical evidence to support a decision either way; more data are required to allow clinicians to make informed decisions about whether or not to restart anticoagulation, and if so, which drug, at what time-point and at what dose/therapeutic target.

Potential impact of new oral anticoagulants on the management of atrial fibrillation-related stroke in primary care

AIM

Anticoagulant prophylaxis with vitamin K antagonists (such as warfarin) is effective in reducing the risk of stroke in patients with atrial fibrillation (AF). New oral anticoagulants have emerged as potential alternatives to traditional oral agents. The purpose of this review was to summarise the effectiveness and safety of rivaroxaban, dabigatran and apixaban in stroke prevention in patients with AF in phase III trials, evaluate their cost-effectiveness and consider the implications for primary care.

METHODOLOGY

A literature search was performed between 2007 and 2012, selecting all phase III trials (ROCKET AF, RE-LY and ARISTOTLE) of new oral anticoagulants and relevant cost-benefit studies.

RESULTS

Evidence shows that all three agents are at least as effective as warfarin in the prevention of stroke and systemic emboli, with similar safety profiles. Cost-benefit studies of rivaroxaban and dabigatran further confirm their potential use as alternatives to warfarin in clinical practice. These observations may allow stratification of the general practice AF population, to help prioritise which patients may benefit from receiving a new oral anticoagulant.

CONCLUSION

The clinical and economic benefits of the new oral anticoagulants, along with appropriate risk stratification, may enable a higher number of patients with AF to receive effective and convenient prophylaxis for stroke prevention.

Screening for atrial fibrillation with baseline and intermittent ECG recording in an out-of-hospital population

BACKGROUND

the objective of this study is to investigate the detection rate of undiagnosed atrial fibrillation (AF) with short intermittent ECG recordings during four weeks among out-of-hospital patients, having at least one additional risk factor (CHADS2) for stroke.

METHOD

DESIGN

Cross-sectional study.

SETTING

Eight family practice centres and two hospital-based out-patient clinics in Sweden.

SUBJECTS

989 out-of-hospital patients, without known AF, having one or more risk factors associated with stroke (CHADS2).

INTERVENTIONS

All individuals were asked to perform 10-second handheld ECG recordings during 28 days, twice daily and when having palpitations.

MAIN OUTCOME MEASURES

Episodes of AF on handheld ECG recordings were defined as irregular supraventricular extrasystoles in series with a duration of 10 seconds.

RESULTS

928 patients completed registration. AF was found in 35 of 928 patients; 3.8% (95% confidence interval [CI] 2.7-5.2). These 35 patients had a mean age of 70.7 years (SD ± 7.7; range 53-85) and a median CHADS2 of 2 (range 1-4).

CONCLUSIONS

Intermittent handheld ECG recording over a four week period had a detection rate of 3.8% newly diagnosed AF, in a population of 928 out-of-hospital patients having at least one additional risk factor for stroke. Intermittent handheld ECG registration is a feasible method to detect AF in patients with an increased risk of stroke in whom oral anticoagulation (OAC) treatment is indicated.

Hormone replacement therapy and risk of new-onset atrial fibrillation after myocardial infarction--a nationwide cohort study

OBJECTIVES

Our aim was to assess the association between use of hormone replacement therapy (HRT) and risk of new-onset atrial fibrillation (AF) after myocardial infarction.

DESIGN, SETTING AND PARTICIPANTS

We used Danish nationwide registers of hospitalizations and prescriptions to identify all women admitted with myocardial infarction in the period 1997 to 2009 and with no known diagnosis of AF. Their use of overall HRT and HRT categories was assessed. Multivariable Cox proportional hazards analysis was used to calculate the risk of new-onset AF first year after discharge, comparing use of HRT to no use.

MAIN OUTCOME MEASURES

New-onset atrial fibrillation.

RESULTS

In the period 1997 to 2009, 32 925 women were discharged alive after MI. In the first year after MI, new-onset AF was diagnosed in 1381 women (4.2%). Unadjusted incidence rates of AF decreased with use of HRT (incidence rate 37.4 for use of overall HRT and 53.7 for no use). Overall HRT was associated with a decreased risk of AF (HR 0.82, 95% confidence interval [CI] 0.68-1.00). The lowest risk of AF was found in women ≥80 years old for use of overall HRT and vaginal estrogen (HR 0.63, CI 0.42-0.94, and HR 0.58, CI 0.34-0.99, respectively). Decreased risk of AF with use of overall HRT and HRT categories was also found in other age groups.

CONCLUSIONS

Use of HRT is associated with a decreased risk of new-onset AF in women with myocardial infarction first year after discharge. The underlying mechanisms remain to be determined. Unmeasured confounding might be one of them.