Increasing trends in hospital care burden of atrial fibrillation in Korea, 2006 through 2015

Racial differences and similarities in atrial fibrillation epidemiology and risk factors in UK Biobank and Korean NHIS-HEALS cohort studies

BACKGROUND

The increasing prevalence of atrial fibrillation (AF) requires efforts to understand racial differences in disease distribution and risk factors.

OBJECTIVE

We aimed to compare associations between risk factors and AF in White Europeans from the UK Biobank and Asians from the Korean National Health Insurance Service-Health Screening (NHIS-HEALS) study.

METHODS

This study included participants from the Korean NHIS-HEALS and UK Biobank. After matching for age and sex, 206,704 participants in the Korean NHIS-HEALS and 206,704 participants in the UK Biobank were enrolled in the study. The incidence of AF, its associations with biomarkers, prevalent cardiovascular disease, and population attributable risk by race were examined.

RESULTS

During a median follow-up of 7.1 years in the Korean NHIS-HEALS and 11.9 years in the UK Biobank, those in the UK Biobank showed a higher incidence and risk of AF (3.99 vs 3.41 per 1000 person-years; hazard ratio, 1.20; 95% confidence interval [CI], 1.15-2.25) compared with the population in the Korean NHIS-HEALS. Body mass index (BMI), systolic blood pressure, alcohol, heart failure, myocardial infarction, and stroke were associated with an increased risk of new-onset AF in both cohorts. Higher BMI and smoking were more strongly related to the increased risk of new-onset AF in the UK Biobank compared with the Korean NHIS-HEALS, with a relative risk ratio of 1.21 (95% CI, 1.17-1.25) and 1.12 (95% CI, 1.02-1.21), respectively.

CONCLUSION

In this first large-scale comparison of White and Asian populations, the cumulative risk for development of AF was higher in the United Kingdom than in Korea. Higher BMI and smoking were associated with a higher risk of AF in the United Kingdom than in Korea.

Invasive strategies for rhythm control of atrial fibrillation: a narrative review

Atrial fibrillation (AF) is the most common sustained tachyarrhythmia and its increasing prevalence has resulted in a growing healthcare burden. A recent landmark randomized trial, the EAST-AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial), highlighted the importance of early rhythm control in AF, which was previously underemphasized. Rhythm control therapy includes antiarrhythmic drugs, direct-current cardioversion, and catheter ablation. Currently, catheter ablation is indicated for patients with AF who are either refractory or intolerant to antiarrhythmic drugs or who exhibit decreased left ventricular systolic function. Catheter ablation can be categorized according to the energy source used, including radiofrequency ablation (RFA), cryoablation, laser ablation, and the recently emerging pulsed field ablation (PFA). Catheter ablation techniques can also be divided into the point-by-point ablation method, which ablates the pulmonary vein (PV) antrum one point at a time, and the single-shot technique, which uses a spherical catheter to ablate the PV antrum in a single application. PFA is known to be applicable to both point-by-point and single-shot techniques and is expected to be promising owing to its tissue specificity, resulting in less collateral damage than catheter ablation involving thermal energy, such as RFA and cryoablation. In this review, we aimed to outline catheter ablation for rhythm control in AF by reviewing previous studies.

Effectiveness and safety of Liriope Tuber (Liriopis seu Ophiopogonis Tuber, Maidong) included traditional herbal medicine for patients with paroxysmal atrial fibrillation: A systematic review, meta-analysis, and network analysis

Background

Conventional medicine (CM) for paroxysmal atrial fibrillation (PAF) have limitations and side effects. Integrative approaches, including traditional herbal medicines like Liriope Tuber, are being explored for potential benefits, although evidence remains limited.

Methods

In April 2023, a literature search was conducted across nine databases, focusing on randomized controlled trials assessing the effects of Liriope Tuber in traditional herbal medicine (LTHM) on PAF. The risk of bias was evaluated using Version 2 of the Cochrane risk-of-bias tool for randomized trials. A random-effects model was employed for the meta-analysis.

Results

A total of 43 studies with 3,743 participants were included. The meta-analysis indicated that adding LTHM to CM reduced PAF frequency (SMD = -0.99, 95 % CI = -1.40 to -0.57, I² = 88 %, N = 16, n = 1266), left atrium diameter (LAD) (MD = -2.39 mm, 95 % CI = -3.09 to -1.68), P-wave dispersion (Pd) (MD = -6.41 ms, 95 % CI = -8.44 to -4.37), high sensitive C-Reactive Protein (hs-CRP) (MD = -1.10 mg/l, 95 % CI = -1.73 to -0.47), and improved left ventricular ejection fraction (LVEF) (MD = 4.71 %, 95 % CI = 3.17 to 6.25). Thirty-four studies raised concerns about bias, with eight showing high risk. Certainty of evidence was rated as "low" for PAF frequency, LAD, Pd, hs-CRP, and LVEF.

Conclusion

LTHM combined with CM may reduce PAF frequency. However, due to the complexity of interventions, with Liriope Tuber being only one component of the regimen, high risk of bias, substantial heterogeneity, and indirectness, interpretations should be cautious.

Study registration

PROSPERO (ID: CRD42023477926).

The anticoagulation one year after ablation of atrial fibrillation in patients with atrial fibrillation (ALONE-AF) trial: Study protocol

Background

The ideal long-term antithrombotic strategy for patients after successful catheter-based atrial fibrillation (AF) ablation is still uncertain. Presently, practices vary, and the advantages of oral anticoagulation (OAC) for the post-ablation population are not clearly established. To date, no randomized trials have addressed this therapeutic question. This study aimed to evaluate whether no OAC therapy is superior to apixaban in reducing the risk of stroke, systemic embolism, or major bleeding among patients without apparent recurrent atrial arrhythmias for at least 1 year after their AF ablation procedure.

Methods

The ALONE-AF trial is a prospective, multicenter, open-label, randomized study with blinded outcome assessment. Patients with AF who have at least one non-gender stroke risk factor (as determined by the CHA2DS2-VASc score) and no documented recurrences of atrial arrhythmia for at least 12 months post-ablation will be randomly assigned to apixaban 5 mg b.i.d. or no OAC therapy. The primary endpoint is a composite outcome of stroke, systemic embolism, and major bleeding. Key secondary outcomes include clinically relevant non-major bleeding, all-cause mortality, myocardial infarction, transient ischemic attack, quality of life, and frailty analysis. Participants will be followed for a period of 2 years. The estimated total sample size is 840 subjects, with 420 subjects in each arm.

Conclusion

The ALONE-AF trial aims to provide robust evidence for the optimal anticoagulation strategy for patients with stroke risk factors following successful AF ablation.

Increased risk of epilepsy after transient global amnesia: A population-based study in South Korea

PURPOSE

This study aimed to investigate the risk of epilepsy after transient global amnesia (TGA).

METHODS

Study population was recruited using the International Classification of Diseases codes from the Korean National Health Insurance Service database between 2002 and 2020. The incidence of epilepsy was compared between the TGA (n=12,390) and non-TGA (n=33,868) groups, determined using 1:3 propensity score matching. Using Cox proportional hazard regression model, we obtained adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for incident epilepsy in the TGA compared with non-TGA group. Logistic regression was performed to examine the independent variables determining incident epilepsy in the TGA group, and adjusted odds ratios (aORs) and 95% CIs were calculated.

RESULTS

The TGA group had a significantly higher cumulative incidence of epilepsy than controls (p <0.001, log-rank test). TGA was significantly associated with incident epilepsy in the Cox model (adjusted HR 1.46, 95% CI 1.36-1.56). The adjusted logistic regression showed that age (per 1 year, aOR 1.02, 95% CI 1.01-1.02), female sex (aOR 0.68, 95% CI 0.60-0.77), hypertension (aOR 1.14, 95% CI 1.00-1.30), diabetes (aOR 1.26, 95% CI 1.10-1.44), stroke (aOR 1.22, 95% CI 1.06-1.40), depression (aOR 1.44, 95% CI 1.22-1.69), anxiety (aOR 1.31, 95% CI 1.14-1.51), alcohol-related disease (aOR 1.96, 95% CI 1.38-2.78), low income (aOR 1.18, 95% CI 1.02-1.36) and rural residence (aOR 1.20, 95% CI 1.02-1.42) were associated with incident epilepsy.

CONCLUSIONS

Our results suggest a longitudinal association of TGA with incident epilepsy.

Long-term outcomes after hospitalization for atrial fibrillation or flutter

BACKGROUND AND AIMS

Atrial fibrillation (AF) and flutter are common causes of hospitalizations but contemporary long-term outcomes following these episodes are uncertain. This study assessed outcomes up to 10 years after an acute AF or flutter hospitalization.

METHODS

Patients hospitalized acutely with a primary diagnosis of AF or flutter from 2008-17 from all public and most private hospitals in Australia and New Zealand were included. Kaplan-Meier methods and flexible parametric survival modelling were used to estimate survival and loss in life expectancy, respectively. Competing risk model accounting for death was used when estimating incidence of non-fatal outcomes.

RESULTS

A total of 260 492 adults (mean age 70.5 ± 14.4 years, 49.6% female) were followed up for 1 068 009 person-years (PY), during which 69 167 died (incidence rate 6.5/100 PY) with 91.2% survival at 1 year, 72.7% at 5 years, and 55.2% at 10 years. Estimated loss in life expectancy was 2.6 years, or 16.8% of expected life expectancy. Re-hospitalizations for heart failure (2.9/100 PY), stroke (1.7/100 PY), and myocardial infarction (1.1/100 PY) were common with respective cumulative incidences of 16.8%, 11.0%, and 7.1% by 10 years. Re-hospitalization for AF or flutter occurred in 21.3% by 1 year, 35.3% by 5 years, and 41.2% by 10 years (11.6/100 PY). The cumulative incidence of patients undergoing catheter ablation of AF was 6.5% at 10 years (1.2/100 PY).

CONCLUSIONS

Patients hospitalized for AF or flutter had high death rates with an average 2.6-year loss in life expectancy. Moreover, re-hospitalizations for AF or flutter and related outcomes such as heart failure and stroke were common with catheter ablation used infrequently for treatment, which warrant further actions.

Modifiable lifestyle factors and lifetime risk of atrial fibrillation: longitudinal data from the Korea NHIS-HealS and UK Biobank cohorts

BACKGROUND

The reason for higher incidence of atrial fibrillation (AF) in Europe compared with East Asia is unclear. We aimed to investigate the association between modifiable lifestyle factors and lifetime risk of AF in Europe and East Asia, along with race/ethnic similarities and disparities.

METHODS

1:1 propensity score matched pairs of 242,763 East Asians and 242,763 White Europeans without AF were analyzed. Modifiable lifestyle factors considered were blood pressure, body mass index, cigarette smoking, diabetes, alcohol consumption, and physical activity, categorized as non-adverse or adverse levels. Lifetime risk of AF was estimated from the index age of 45 years to the attained age of 85 years, accounting for the competing risk of death.

RESULTS

The overall lifetime risk of AF was higher in White Europeans than East Asians (20.9% vs 15.4%, p < 0.001). The lifetime risk of AF was similar between the two races in individuals with non-adverse lifestyle factor profiles (13.4% vs 12.9%, p = 0.575), whereas it was higher in White Europeans with adverse lifestyle factor profiles (22.1% vs 15.8%, p < 0.001). The difference in the lifetime risk of AF between the two races increased as the burden of adverse lifestyle factors worsened (1 adverse lifestyle factor; 4.3% to ≥ 3 adverse lifestyle factors; 11.2%). Compared with East Asians, the relative risk of AF in White Europeans was 23% and 62% higher for one (hazard ratio [HR] 1.23, 95% confidence interval [CI] 1.16-1.29) and ≥ 3 adverse lifestyle factors (HR 1.62, 95% CI 1.51-1.75), respectively.

CONCLUSIONS

The overall higher lifetime risk of AF in White Europeans compared with East Asians might be attributable to adverse lifestyle factors. Adherence to healthy lifestyle factors was associated with the lifetime risk of AF of about 1 in 8 regardless of race/ethnicity.

Reduction of Upper Gastrointestinal Bleeding Risk With Proton Pump Inhibitor Therapy in Asian Patients With Atrial Fibrillation Receiving Direct Oral Anticoagulant: A Nationwide Population-based Cohort Study

BACKGROUND & AIMS

In patients with atrial fibrillation (AF) receiving direct oral anticoagulant (DOAC), upper gastrointestinal bleeding (UGIB) is a serious complication. There are limited data on the benefit of preventive proton pump inhibitor (PPI) use to reduce the risk of UGIB in DOAC users.

METHODS

We included patients with AF receiving DOAC from 2015 to 2020 based on the Korean Health Insurance Review and Assessment database. The propensity score (PS) weighting method was used to compare patients with PPI use and those without PPI use. The primary outcome was hospitalization for UGIB. Weighted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were evaluated using the Cox proportional hazards regression model.

RESULTS

A total of 165,624 patients were included (mean age: 72.2 ± 10.8 years; mean CHA2DS2-VASc score: 4.3 ± 1.8; mean HAS-BLED score: 3.3 ± 1.2). Among them, 99,868 and 65,756 were in the non-PPI group and PPI group, respectively. During a median follow-up of 1.5 years, the PPI group was associated with lower risks of hospitalization for UGIB and UGIB requiring red blood cell transfusion than non-PPI group (weighted HR, 0.825; 95% CI, 0.761-0.894 and 0.798; 95% CI, 0.717-0.887, respectively, both P < .001). The benefits of PPI on the risk of hospitalization for UGIB were greater in those with older age (≥75 years), higher HAS-BLED score (≥3), prior GIB history, and concomitant use of antiplatelet agent (all P-for-interaction < .1). Low-dose PPI was consistently associated with a lower risk of significant UGIB by 43.6-49.3% (P < .001).

CONCLUSIONS

In this large Asian cohort of patients with AF on DOAC, PPI co-therapy is beneficial for reducing the risk of hospitalization for UGIB, particularly in high-risk patients.

Lower Atrial Fibrillation Risk With Sodium-Glucose Cotransporter 2 Inhibitors Than With Dipeptidyl Peptidase-4 Inhibitors in Individuals With Type 2 Diabetes: A Nationwide Cohort Study

BACKGROUND AND OBJECTIVES

Accumulating evidence shows that sodium-glucose cotransporter 2 inhibitors (SGLT2is) reduce adverse cardiovascular outcomes. However, whether SGLT2i, compared with other antidiabetic drugs, reduce the new development of atrial fibrillation (AF) is unclear. In this study, we compared SGLT2i with dipeptidyl peptidase-4 inhibitors (DPP-4is) in terms of reduction in the risk of AF in individuals with type 2 diabetes.

METHODS

We included 42,786 propensity score-matched pairs of SGLT2i and DPP-4i users without previous AF diagnosis using the Korean National Health Insurance Service database between May 1, 2016, and December 31, 2018.

RESULTS

During a median follow-up of 1.3 years, SGLT2i users had a lower incidence of AF than DPP-4i users (1.95 vs. 2.65 per 1,000 person-years; hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.55-0.97; p=0.028]). In individuals without heart failure, SGLT2i users was associated with a decreased risk of AF incidence (HR, 0.70; 95% CI, 0.52-0.94; p=0.019) compared to DPP-4i users. However, individuals with heart failure, SGLT2i users was not significantly associated with a change in risk (HR, 1.04; 95% CI, 0.44-2.44; p=0.936).

CONCLUSIONS

In this nationwide cohort study of individuals with type 2 diabetes, treatment with SGLT2i was associated with a lower risk of AF compared with treatment with DPP-4i.

Multimorbidity in atrial fibrillation for clinical implications using the Charlson Comorbidity Index

BACKGROUND

Predicting survival in atrial fibrillation (AF) patients with comorbidities is challenging. This study aimed to assess multimorbidity in AF patients using the Charlson Comorbidity Index (CCI) and its clinical implications.

METHODS

We analyzed 451,368 participants from the Korea National Health Insurance Service-Health Screening cohort (2002-2013) without prior AF diagnoses. Patients were categorized into new-onset AF and non-AF groups, with a high CCI defined as ≥4 points. Antithrombotic treatment and outcomes (all-cause death, stroke, major bleeding, and heart failure [HF] hospitalization) were evaluated over 9 years.

RESULTS

In total, 9.5% of the enrolled patients had high CCI. During follow-up, 12,241 patients developed new-onset AF. Among AF patients, antiplatelet drug use increased significantly in those with high CCI (adjusted odds ratio [OR] 1.05, 95%confidence interval [CI] 1.02-1.08, P < .001). However, anticoagulants were significantly less prescribed in patients with high CCI (OR 0.97, 95%CI 0.95-0.99, P = .012). Incidence of adverse events (all-cause death, stroke, major bleeding, HF hospitalization) progressively increased in this order: low CCI without AF, high CCI without AF, low CCI with AF, and high CCI with AF (all P < .001). Furthermore, high CCI with AF had a significantly higher risk compared to low CCI without AF (all-cause death, adjusted hazard ratio [aHR] 2.52, 95% CI 2.37-2.68, P < .001; stroke, aHR 1.43, 95% CI 1.29-1.58, P < .001; major bleeding, aHR 1.14, 95% CI 1.04-1.26, P = .007; HF hospitalization, aHR 4.75, 95% CI 4.03-5.59, P < .001).

CONCLUSIONS

High CCI predicted increased antiplatelet use and reduced oral anticoagulant prescription. AF was associated with higher risks of all-cause death, stroke, major bleeding, and HF hospitalization compared to high CCI.

Increased Risk of Dementia after Transient Global Amnesia: A Nationwide Population-Based, Longitudinal Follow-Up Study in South Korea

INTRODUCTION

The long-term cognitive outcomes after transient global amnesia (TGA) have been contradictory in the literature. Our study aimed to longitudinally investigate the association between TGA and incident dementia using long-term data from a nationwide population-based cohort in South Korea.

METHODS

The study population was recruited between 2002 and 2020 using the International Classification of Diseases (Tenth Revision; ICD-10) codes from the Korean National Health Insurance Service database. The cumulative incidence curve was plotted to compare the incidence of dementia between the TGA (ICD-10 code G45.4; n = 10,276) and non-TGA (n = 27,389) groups, determined using 1:3 propensity score matching. Using Cox proportional hazard regression models, we obtained crude and adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the incident dementia in patients with TGA compared to non-TGA controls. To examine independent variables determining dementia in the TGA group, logistic regression analysis was performed, and adjusted odds ratios (aORs) and 95% CIs were calculated.

RESULTS

The TGA group had a significantly higher cumulative incidence of dementia than the non-TGA group (p < 0.001, log-rank test). TGA was significantly associated with incident dementia in the univariate and multivariate Cox models (HR 1.34, 95% CI 1.28-1.39 and aHR 1.40, 95% CI 1.34-1.46, respectively). The adjusted logistic regression for incident dementia in the TGA group showed that age (per 1 year, aOR 1.09, 95% CI 1.09-1.10), female sex (aOR 1.31, 95% CI 1.18-1.45), diabetes (aOR 1.21, 95% CI 1.08-1.35), stroke (aOR 1.30, 95% CI 1.16-1.46), depression (aOR 1.53, 95% CI 1.33-1.76), anxiety (aOR 1.24, 95% CI 1.01-1.39), and rural residence (aOR 1.24, 95% CI 1.10-1.41) were independently associated with incident dementia.

CONCLUSION

Our results suggest a longitudinal association of TGA with incident dementia.

Associations of combined polygenic risk score and glycemic status with atrial fibrillation, coronary artery disease and ischemic stroke

BACKGROUND

It is unknown whether high hemoglobin A1c (HbA1c) is associated with increases in the risk of cardiovascular disease among individuals with elevated genetic susceptibility. We aimed to investigate the association between HbA1c and atrial fibrillation (AF), coronary artery disease (CAD), and ischemic stroke according to the polygenic risk score (PRS).

METHODS

The UK Biobank cohort included 502,442 participants aged 40-70 years who were recruited from 22 assessment centers across the United Kingdom from 2006 to 2010. This study included 305,605 unrelated individuals with available PRS and assessed new-onset AF, CAD, and ischemic stroke. The participants were divided into tertiles based on the validated PRS for each outcome. Within each PRS tertiles, the risks of incident events associated with HbA1c levels were investigated and compared with HbA1c < 5.7% and low PRS. Data were analyzed from November 2022 to May 2023.

RESULTS

Of 305,605 individuals, 161,605 (52.9%) were female, and the mean (SD) age was 56.6 (8.1) years. During a median follow-up of 11.9 (interquartile range 11.1-12.6) years, the incidences of AF, CAD, and ischemic stroke were 4.6, 2.9 and 1.1 per 100 person-years, respectively. Compared to individuals with HbA1c < 5.7% and low PRS, individuals with HbA1c ≥ 6.5% and high PRS had a 2.67-times higher risk for AF (hazard ratio [HR], 2.67; 95% confidence interval (CI), 2.43-2.94), 5.71-times higher risk for CAD (HR, 5.71; 95% CI, 5.14-6.33) and 2.94-times higher risk for ischemic stroke (HR, 2.94; 95% CI, 2.47-3.50). In the restricted cubic spline models, while a U-shaped trend was observed between HbA1c and the risk of AF, dose-dependent increases were observed between HbA1c and the risk of CAD and ischemic stroke regardless PRS tertile.

CONCLUSIONS

Our results suggest that the nature of the dose-dependent relationship between HbA1c levels and cardiovascular disease in individuals with different PRS is outcome-specific. This adds to the evidence that PRS may play a role together with glycemic status in the development of cardiovascular disease.

Cloud-based digital healthcare development for precision medical hospital information system

Aim: This study aims to develop a cloud-based digital healthcare system for precision medical hospital information systems (P-HIS). Methods: In 2020, international standardization of P-HIS clinical terms and codes was performed. In 2021, South Korea's first tertiary hospital cloud was established and implemented successfully. Results: P-HIS was applied at Korea's first tertiary general hospital. Common data model-compatible precision medicine/medical service solutions were developed for medical support. Ultrahigh-quality medical data for precision medicine were acquired and built using big data. Joint global commercialization and dissemination/spreading were achieved using the P-HIS consortium and global common data model-based observational medical outcome partnership network. Conclusion: To provide personalized precision medical services in the future, establishing and using big medical data is essential.

Socioeconomic Status and Burden of Atrial Fibrillation Hospitalizations among Black US Adults: A Fifteen Year Analysis

BACKGROUND

Socioeconomic status (SES) may help delineate inequities in atrial fibrillation (AF) among Blacks versus non-blacks.

METHODS

We queried the National Inpatient Sample database from January 2004 to December 2018 to determine trends in AF hospitalizations and in-hospital mortality stratified by Black race and SES.

RESULTS

Total admissions for AF in the US has increased by 12% from 1077 to 1202 per 1 million US adults. Among patients hospitalized with AF, the proportion of Black adults is increasing. In those of low SES, both Black and non-black patients have had increases in AF hospitalizations. In those of high SES, Black patients have had a modest increase while non-black patients have had a progressive decrease in rate of hospitalizations. Overall, in-hospital mortality rates improved in Blacks and non-blacks, regardless of SES.

CONCLUSION

Joint associations of SES and race can further qualify disparities in AF care.

Association of obesity with incident atrial fibrillation in Korea and the United Kingdom

Obesity has been linked to atrial fibrillation (AF) burden and severity, and epidemiological studies suggest that AF is more prevalent in whites than Asian. We aimed to investigate whether obesity mediates associations with AF in Europe and Asia using patient-level data comparisons of two cohort studies. Using Korean National Health Insurance Service's Health Screening (NHIS-HealS) and U.K. Biobank data, we included 401,206 Korean and 477,926 British aged 40-70 years without previous AF who received check-ups. The incidence and risk of AF were evaluated regarding different body mass index (BMI) values. The obese proportion (BMI ≥ 30.0 kg/m², 2.8% vs. 24.3%, P < 0.001) was higher in the U.K. than the Korean. In the Korean and U.K. cohort, the age- and sex-adjusted incidence rates of AF were 4.97 and 6.54 per 1000 person-years among obese individuals. Compared to Koreans, the risk of AF was higher in the British population, with adjusted hazard ratios of 1.41 (Korea, 95% CI 1.26-1.58) and 1.68 (UK, 95% CI 1.54-1.82) in obese participants (P for interaction < 0.05). Obesity was associated with AF in both populations. British subjects had a greater incidence of AF related to the high proportion of obese individuals, especially participants in the obesity category, the risk of AF also increased.

Associations of high-normal blood pressure and impaired fasting glucose with atrial fibrillation

OBJECTIVE

To investigate the association of high-normal blood pressure (BP) and impaired fasting glucose (IFG) with the risk of atrial fibrillation (AF) in two cohorts.

METHODS

The Korean National Health Insurance Service-Health Screening (K-NHIS-HealS, 2002-2003, follow-up until 2013) Study and the UK Biobank (2007-2010, follow-up until 2021) were evaluated. We used Cox proportional hazards regression models to evaluate the associations of high-normal BP and IFG with incident AF.

RESULTS

In the K-NHIS-HealS and the UK Biobank, 2346 and 5314 incident AF events were recorded during the mean follow-up of 7.4 and 11.8 years. The adjusted HRs (95% CIs) for AF in the Korean and UK cohorts were 1.11 (1.02 to 1.21) and 1.07 (1.01 to 1.13) in individuals with high-normal BP; and 1.14 (1.04 to 1.25) and 1.10 (1.01 to 1.20) in individuals with IFG, respectively. The AF risk showed a dose-response relationship with BP and fasting blood glucose level. The risk of incident AF was increased by the combination of high-normal BP and IFG.

CONCLUSIONS

In healthy individuals, high-normal BP and IFG were important risk factors for AF. When high-normal BP and IFG were combined, the risk of new-onset AF was significantly increased. These findings may suggest that lifestyle interventions for high-normal BP and IFG should be considered to reduce the risk of AF.

Early Rhythm Control in Patients With Incident Atrial Fibrillation Who Had a Prior Stroke

BACKGROUND

There are limited data regarding the benefit of early rhythm control therapy for secondary prevention for stroke in patients with atrial fibrillation (AF).

OBJECTIVES

This study aimed to compare the risk of recurrent stroke between early rhythm control therapy and usual care in patients with new-onset AF and a history of prior stroke.

METHODS

Using the Korean nationwide claims database, the investigators identified patients who were newly diagnosed with AF and had a history of prior stroke. Patients who received rhythm control therapy, including antiarrhythmic drug, direct current cardioversion, or AF catheter ablation, within 1 year after incident AF were defined as the early rhythm control group, and the others were the usual care group. The propensity score weighting method was used to balance baseline characteristics between the 2 groups. Incident stroke was evaluated as a primary outcome.

RESULTS

A total of 53,509 patients were included (12,455 in the early rhythm control group and 41,054 in the usual care group). All patients were prescribed oral anticoagulants. During a median 2.6 years of follow-up, 4,382 patients had an incident stroke (incidence rate: 2.6 per 100 person-years). Early rhythm control was associated with a lower risk of recurrent stroke compared to the risk associated with usual care (weighted HR: 0.720; 95% CI: 0.666-0.779; P < 0.001).

CONCLUSIONS

Early rhythm control within 1 year after AF diagnosis might be beneficial to prevent recurrent stroke in patients with incident AF and a history of stroke. Integrated care, including optimal rhythm control with appropriate anticoagulation, should be considered in this population.

Cost-effectiveness of rhythm control strategy: Ablation versus antiarrhythmic drugs for treating atrial fibrillation in Korea based on real-world data

Background

Ablation-based treatment has emerged as an alternative rhythm control strategy for symptomatic atrial fibrillation (AF). Recent studies have demonstrated the cost-effectiveness of ablation compared with medical therapy in various circumstances. We assessed the economic comparison between ablation and medical therapy based on a nationwide real-world population.

Methods and findings

For 192,345 patients with new-onset AF (age ≥ 18 years) identified between August 2015 and July 2018 from the Korean Health Insurance Review and Assessment Service (HIRA) database, medical resource use data were collected to compare AF patients that underwent ablation (N = 2,131) and those administered antiarrhythmic drugs (N = 8,048). Subsequently, a Markov chain Monte Carlo model was built. The patients had at least one risk factor for stroke, and the base-case used a 20-year time horizon, discounting at 4.5% annually. Transition probabilities and costs were estimated using the present data, and utilities were derived from literature review. The costs were converted to US $ (2019). Sensitivity analyses were performed using probabilistic and deterministic methods. The net costs and quality-adjusted life years (QALY) for antiarrhythmic drugs and ablation treatments were $37,421 and 8.8 QALYs and $39,820 and 9.3 QALYs, respectively. Compared with antiarrhythmic drugs, incremental cost-effectiveness ratio of ablation was $4,739/QALY, which is lower than the willingness-to-pay (WTP) threshold of $32,000/QALY.

Conclusion

In symptomatic AF patients with a stroke risk under the age of 75 years, ablation-based rhythm control is potentially a more economically attractive option compared with antiarrhythmic drug-based rhythm control in Korea.

Impact of frailty on early rhythm control outcomes in older adults with atrial fibrillation: A nationwide cohort study

Purpose

Rhythm-control therapy administered early following the initial diagnosis of atrial fibrillation (AF) has superior cardiovascular outcomes compared to rate-control therapy. Frailty is a key factor in identifying older patients' potential for improvement after rhythm-control therapy. This study evaluated whether frailty affects the outcome of early rhythm-control therapy in older patients with AF.

Methods

From the Korean National Health Insurance Service database (2005-2015), we collected 20,611 populations aged ≥65 years undergoing rhythm- or rate-control therapy initiated within 1 year of AF diagnosis. Participants were emulated by the EAST-AFNET4 trial, and stratified into non-frail, moderately frail, and highly frail groups based on the hospital frailty risk score (HFRS). A composite outcome of cardiovascular-related mortality, myocardial infarction, hospitalization for heart failure, and ischemic stroke was compared between rhythm- and rate-control.

Results

Early rhythm-control strategy showed a 14% lower risk of the primary composite outcome in the non-frail group [weighted incidence 7.3 vs. 8.6 per 100 person-years; hazard ratio (HR) 0.86, 95% confidence interval (CI) 0.79-0.93, p < 0.001] than rate-control strategy. A consistent trend toward a lower risk of early rhythm-control was observed in the moderately frail (HR 0.91, 95% CI 0.81-1.02, p = 0.09) and highly frail (HR 0.93, 95% CI 0.75-1.17, p = 0.55) groups.

Conclusion

Although the degree attenuated with increasing frailty, the superiority of cardiovascular outcomes of early rhythm-control in AF treatment was maintained without increased risk for safety outcomes. An individualized approach is required on the benefits of early rhythm-control therapy in older patients with AF, regardless of their frailty status.

Impact of Socioeconomic Status on Emergency Department Visits in Patients With Atrial Fibrillation: A Nationwide Population-Based Cohort Study

Background Socioeconomic status (SES) differences could influence management and clinical outcomes in patients with atrial fibrillation (AF), reflecting health inequalities. The authors aimed to investigate emergency department (ED) visits in patients with AF according to SES level. Methods and Results The authors performed a cross-sectional analysis of ED visits in patients with nonvalvular AF using the Korean National Health Insurance Service database in 2016. The patients were divided into health premium quartiles and medical aid groups, with quartile 4 the highest SES and medical aid the lowest SES. Among patients with AF, patients who had ≥1 ED visits in 2016 were identified. The prevalence and cause of ED visits, 30- and 90-day mortality, and rehospitalization risk after ED visits were evaluated. Among the total 371 017 AF patients, 99 306 patients visited the ED in 2016. The medical aid group showed the highest ED visit rate (n=11 833, 38.0%), and patients with the highest quartile of SES (quartile 4 group) showed the lowest ED visit rate (n=38 037, 30.0%). The most common cause of ED visits was cerebral infarction in all groups. The 30- and 90-day mortality rates and rehospitalization risk after ED visits was higher in groups with lower SES. Conclusions Patients with AF and with lower SES had a higher risk of ED visit rate, higher 30- and 90-day mortality rates, and rehospitalization risk after ED visit. Tailored AF management according to different SES levels in patients with AF is needed to improve clinical outcomes.

Global disparities in arrhythmia care: Mind the gap

Delivery of comprehensive arrhythmia care requires the simultaneous presence of many resources. These include complex hospital infrastructure, expensive implantable equipment, and expert personnel. In many low- and middle-income countries (LMICs), at least 1 of these components is often missing, resulting in a gap between the demand for arrhythmia care and the capacity to supply care. In addition to this treatment gap, there exists a training gap, as many clinicians in LMICs have limited access to formal training in cardiac electrophysiology. Given the progressive increase in the burden of cardiovascular diseases in LMICs, these patient care and clinical training gaps will widen unless further actions are taken to build capacity. Several strategies for building arrhythmia care capacity in LMICs have been described. Medical missions can provide donations of both equipment and clinical expertise but are only intermittently present and therefore are not optimized to provide the longitudinal support needed to create self-sustaining infrastructure. Use of donated or reprocessed equipment (eg, cardiac implantable electronic devices) can reduce procedural costs but does not address the need for infrastructure, including diagnostics and expert personnel. Collaborative efforts involving multiple stakeholders (eg, professional organizations, government agencies, hospitals, and educational institutions) have the potential to provide longitudinal support of both patient care and clinician education in LMICs.

Catheter ablation of symptomatic atrial fibrillation: Sex, ethnicity, and socioeconomic disparities

Catheter ablation for treatment of atrial fibrillation (AF), AF ablation, is more effective than antiarrhythmic drugs in reducing AF burden, reducing symptoms and increasing health-related quality of life. Although females more often experience AF-related symptoms, and have more severe symptoms, have lower quality of life, and experience more serious adverse effects of antiarrhythmic drugs than males, they are less likely to undergo AF ablation. Potential explanations for the disparity include older age at diagnosis, longer AF duration, a greater number of comorbidities, more extensive atrial fibrosis, and presumed lower success rate and more complications after AF ablation in women. Studies have failed to show sex-related differences in AF recurrence or serious complications following AF ablation but show more nuisance bleeds in women. Ethnic minorities, such as African Americans and Latin Americans, and individuals of low socioeconomic status are also less likely to undergo AF ablation, possibly associated with greater numbers of comorbidities, lack of patient advocacy, healthcare costs, and inadequate insurance coverage. Inclusion of marginalized patient groups in clinical trials of AF treatment and a personalized, patient-centered approach may expand equality in utilization of AF ablation.

Association between exercise habit changes and mortality following a cardiovascular event

OBJECTIVE

To investigate the associations between exercise habit changes following an incident cardiovascular event and mortality in older adults.

METHODS

We analysed the relationship between exercise habit change and all-cause, cardiovascular and non-cardiovascular deaths in adults aged ≥60 years between 2003 and 2012 who underwent two consecutive health examinations within 2 years before and after diagnosis of cardiovascular disease (CVD). They were categorised into four groups according to exercise habit changes: persistent non-exercisers, exercise dropouts, new exercisers and exercise maintainers. Differences in baseline characteristics were adjusted using inverse probability of treatment weighting.

RESULTS

Of 6076 participants, the median age was 72 (IQR 69-76) years and men accounted for 50.6%. Compared with persistent non-exercisers (incidence rate (IR) 4.8 per 100 person-years), new exercisers (IR 3.5, HR 0.73, 95% CI 0.58 to 0.91) and exercise maintainers (IR 2.9, HR 0.53, 95% CI 0.38 to 0.73) were associated with reduced risk of all-cause death. The rate of non-cardiovascular death was significantly lower in new exercisers (IR 2.3, HR 0.73, 95% CI 0.56 to 0.95) and exercise maintainers (IR 2.3, HR 0.61, 95% CI 0.42 to 0.90) than in persistent non-exercisers (IR 3.2). Also, trends towards reduced cardiovascular death in new exercisers and exercise maintainers were observed (p value for trend <0.001).

CONCLUSIONS

More virtuous exercise trajectories in older adults with CVD are associated with lower mortality rates. Our results support public health recommendations for older adults with CVD to perform physical activity.

Effect of epicardial fat volume on outcomes after left atrial posterior wall isolation in addition to pulmonary vein isolation in patients with persistent atrial fibrillation

Background

Greater epicardial adipose tissue (EAT) is related to higher recurrences after atrial fibrillation catheter ablation (AFCA). We investigated the effects of posterior wall box isolation (POBI) in conjunction with circumferential pulmonary vein isolation (CPVI) on rhythm outcomes according to varying EAT volumes among patients with persistent atrial fibrillation (PeAF).

Materials and methods

We included 1,187 patients with PeAF undergoing a de novo AFCA including those receiving CPVI alone (n = 687) and those receiving additional POBI (n = 500). The rhythm outcomes at 2 years post-AFCA were compared in subgroups stratified by the EAT volume using propensity overlap weighting.

Results

A reduced EAT volume was linearly associated with more favorable rhythm outcomes for additional POBI than for CPVI alone (P for interaction = 0.002). Among the patients with smaller EAT volumes (≤116.23 mL, the median value, n = 594), additional POBI was associated with a reduced AF recurrence risk as compared to CPVI only [weighted HR (hazard ratio) 0.74, 95% CI (confidence interval) 0.56-0.99]. In contrast, among the remaining 593 patients with greater EAT volumes (>116.23 mL), No difference was observed in the recurrence risk between the additional POBI and CPVI alone groups (weighted HR 1.13, 95% CI 0.84-1.52). Among 205 patients with repeat ablations, the POBI reconnection rate was more frequent in the large EAT group (77.4%) than in the small EAT group (56.7%, P = 0.034).

Conclusion

While PeAF patients with a smaller EAT volume averted AF recurrence by additional POBI after CPVI, no benefit of the POBI was observed in those with a greater EAT volume.

Temporal trend of first-ever ischaemic stroke incidence from 2010 to 2019 in South Korea: a nationwide retrospective cohort study

OBJECTIVE

Ischaemic stroke incidence is on the decline globally, but the trend in South Korea is unknown. In this study, the 10-year incidence trends of first-ever ischaemic stroke in South Korea were evaluated.

DESIGN, SETTING AND PARTICIPANTS

The National Health Insurance Services medical claim data were used to construct 10 annual cohorts of adults aged 20 years and older, who had not been diagnosed with stroke, to find out the incidence trends of first-ever ischaemic stroke from 2010 to 2019.

OUTCOME MEASURES

The primary outcomes were crude and age-adjusted incidence rates for 10 years. Crude incidence rates of the age groups and incidence age statistics were calculated. For comparison among the income groups, age-adjusted incidence rates were used. Incidence rates in all the groups were analysed separately by sex.

RESULTS

Age-standardised incidence rates of ischaemic stroke per 100 000 were 101.0 in men, and 67.6 in women in 2010; and 92.2 in men, and 55.0 in women in 2019. By age group, there was a decrease in women over 40 years of age, and men over 60 years of age. The relative difference in stroke incidence rates between medical aid beneficiaries and the highest income group increased from 1.5 to 1.87 over 10 years.

CONCLUSIONS

Age-standardised incidence rate of ischaemic stroke has decreased from 2010 to 2019 for both man and women. The incidence rate was stable in the younger age groups and decreased in the older age groups, and the disparities between income groups have widened over the past decade. Stroke prevention strategies are needed for the younger age group and the low-income group. Further research is needed to study the risk factors contributing to the incidence of ischaemic stroke in different groups.

Economic evaluation of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs) for stroke prevention in patients with atrial fibrillation: a systematic review and meta-analysis

OBJECTIVES

To assess cost-effectiveness of direct oral anticoagulants (DOACs) compared with vitamin K antagonists (VKAs) for stroke prevention in atrial fibrillation (AF) by pooling incremental net benefits (INBs).

DESIGN

Systematic review and meta-analysis.

SETTING

We searched PubMed, Scopus and Centre for Evaluation of Value and Risks in Health Registry from inception to December 2019.

PARTICIPANTS

Patients with AF.

MAIN OUTCOME MEASURES

The INB was defined as a difference of incremental effectiveness multiplied by willing to pay threshold minus the incremental cost; a positive INB indicated favour treatment. These INBs were pooled (stratified by level of country income, perspective, time-horizon, model types) with a random-effects model if heterogeneity existed, otherwise a fixed effects model was applied. Heterogeneity was assessed using Q test and I² statistic. Risk of bias was assessed using the economic evaluations bias (ECOBIAS) checklist.

RESULTS

A total of 100 eligible economic evaluation studies (224 comparisons) were included. For high-income countries (HICs) from a third-party payer (TPP) perspective, the pooled INBs for DOAC versus VKA pairs were significantly cost-effective with INBs (95% CI) of $6632 ($2961.67 to $10 303.72; I²=59.9%), $6353.24 ($4076.03 to $8630.45; I²=0%), $7664.58 ($2979.79 to $12 349.37; I²=0%) and $8573.07 ($1877.05 to $15 269.09; I²=0%) for dabigatran, apixaban, rivaroxaban and edoxaban relative to VKA, respectively but only dabigatran was significantly cost-effective from societal perspective (SP) with an INB of $11 746.96 ($2429.34 to $21 064.59; I²=52.4%). The pooled INBs of all comparisons for upper-middle income countries (UMICs) were not significantly cost-effective. The ECOBIAS checklist indicated that risk of bias was mostly low for most items with the exception of five items which should be less influenced on pooling INBs.

CONCLUSIONS

Our meta-analysis provides comprehensive economic evidence that allows policy makers to generalise cost-effectiveness data to their local context. All DOACs may be cost-effective compared with VKA in HICs with TPP perspective. The pooling results produced moderate to high heterogeneity particularly in UMICs. Further studies are required to inform UMICs with SP.

PROSPERO REGISTERATION NUMBER

CRD 42019146610.

Optimal Rhythm Control Strategy in Patients With Atrial Fibrillation

In the recent EAST-AFNET 4 trial, early rhythm control reduced the risk of adverse cardiovascular events compared with usual care in patients recently diagnosed as atrial fibrillation (AF). Recent observational studies from Korean nationwide claim data confirmed and extended the findings from controlled trials. The beneficial effect of rhythm control on cardiovascular outcomes was not obvious in those who had been diagnosed with AF more than 1 year ago. Especially, early initiation of rhythm control was related to the lower risk of stroke and hospitalization due to heart failure. Finally, early rhythm control treatment was also effective in patients with asymptomatic AF but less effective in older adults. Therefore, in patients with AF, rhythm control should be considered at the earliest stage, regardless of symptom.

For almost 20 years, data regarding the effect of rhythm control therapy for atrial fibrillation (AF) on cardiovascular prognosis in comparison with rate control therapy has not been conclusive. The safety of rhythm control and anticoagulation therapy has generally improved. Recently, it was revealed that a rhythm-control strategy reduced the risk of adverse cardiovascular events than usual rate control in patients with recent AF (diagnosed within 1 year). Within 1 year after the AF diagnosis, early initiation of rhythm control led to more favorable cardiovascular outcomes than rate control. Early rhythm control reduced the risks of stroke and heart failure-related admission than rate control. Moreover, rhythm control was associated with lower dementia risk than rate control. Finally, early rhythm control treatment was also effective in patients with asymptomatic AF but less effective in older adults. Therefore, in patients with AF, rhythm control should be considered at earlier stages, regardless of symptom.

Risk of Dementia After Smoking Cessation in Patients With Newly Diagnosed Atrial Fibrillation

IMPORTANCE

Incident atrial fibrillation (AF) is associated with an increased risk of dementia. However, data on the association between smoking cessation after AF diagnosis and dementia risk are limited.

OBJECTIVE

To evaluate the association between changes in smoking status after AF diagnosis and dementia risk.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide cohort study with 126 252 patients used data from the Korean National Health Insurance Service database, including patients who had a national health checkup examination within 2 years before and after AF diagnosis between January 1, 2010, and December 31, 2016. Based on their smoking status, participants were classified as never smokers, ex-smokers, quit smokers, and current smokers. Ex-smokers were defined as those who had quit smoking before the first examination and remained quit until the second examination. Patients who were current smokers at the first health examination but had quit smoking before the second examination were classed as quit smokers. The index date was the second health examination. Patients were followed up until dementia, death, or the study period ended (December 31, 2017), whichever occurred first. Data were analyzed from January 13, 2020, to March 29, 2022.

EXPOSURES

Smoking cessation after newly diagnosed AF.

MAIN OUTCOMES AND MEASURES

Dementia, including Alzheimer disease and vascular dementia, was the primary outcome. Cox proportional hazards regression model was used to estimate hazard ratios.

RESULTS

A total of 126 252 patients (mean [SD] age, 62.6 [12.0] years; 61.9% men) were included in the analysis. The mean (SD) CHA2DS2-VASc score, which measures the risk of ischemic stroke, was 2.7 (1.7). Smoking status of the total study population was as follows: 65 579 never smokers (51.9%), 34 670 ex-smokers (27.5%), 8919 quit smokers (7.1%), and 17 084 current smokers (13.5%). During a median of 3 years of follow-up, dementia occurred in 5925 patients (1.11 per 1000 person-years). After multivariable adjustment, the risk of quit smokers was significantly lower than that of current smokers (hazard ratio, 0.83 [95% CI, 0.72-0.95]).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that all types of smoking were associated with a significantly higher risk of dementia in patients with new-onset AF. Smoking cessation after AF diagnosis was associated with a lower risk of dementia than among current smokers. These findings may support promoting smoking cessation to reduce dementia risk in patients with new-onset AF.

Increased Risk of Cardio-Cerebrovascular Diseases in Migraine Patients: A Nationwide Population-Based, Longitudinal Follow-Up Study in South Korea

Background and Purpose

Migraine is reportedly associated with several cardio-cerebrovascular diseases (CCDs), but some of these diseases have not received sufficient attention. We thus attempted to determine the associations of migraine with peripheral arterial disease (PAD), ischemic heart disease (IHD), atrial fibrillation/flutter (AF), ischemic stroke (IS), and hemorrhagic stroke (HS).

Methods

The study population was recruited by applying International Classification of Diseases, Tenth Revision (ICD-10) codes to the database of the Korean National Health Insurance Service from 2002 to 2018. Cumulative incidence curves were plotted to compare the incidence rates of CCDs between the migraine (ICD-10 code G43; n=130,050) and nonmigraine (n=130,050) groups determined using 1:1 propensity-score matching. Cox proportional-hazards regression models were used to obtain adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for CCDs in patients with any migraine, migraine with aura (n=99,751), and migraine without aura (n=19,562) compared with nonmigraine controls.

Results

For all CCDs, the cumulative incidence rates were higher in the migraine group than the nonmigraine group (p<0.001 in log-rank test). Any migraine, irrespective of the presence of aura, was associated with PAD (aHR 2.29, 95% CI 2.06–2.53), IHD (aHR 2.17, 95% CI 2.12–2.23), AF (aHR 1.84, 95% CI 1.70–1.99), IS (aHR 2.91, 95% CI 2.67–3.16), and HS (aHR 2.46, 95% CI 2.23–2.71). aHR was higher in female than in male migraineurs for all of the CCDs.

Conclusions

Associations of migraine with CCDs have been demonstrated, which are stronger in females than in males.

Age and Outcomes of Early Rhythm Control in Patients With Atrial Fibrillation: Nationwide Cohort Study

OBJECTIVES

This study sought to investigate whether the effects of early rhythm control differ according to age.

BACKGROUND

Rhythm control, compared with usual care among patients recently diagnosed with atrial fibrillation (AF), was found to be associated with a lower risk of adverse cardiovascular outcomes. It is unclear whether the results can be generalized for older adults.

METHODS

This retrospective population-based cohort study included 31,220 patients with AF, from the Korean National Health Insurance Service database, undergoing rhythm control (antiarrhythmic drugs or ablation) or rate control therapy, initiated within 1 year of AF diagnosis. A composite outcome of cardiovascular death, ischemic stroke, hospitalization for heart failure, or myocardial infarction was compared in subgroups stratified by age.

RESULTS

Compared with rate control, early rhythm control was associated with a lower risk of the primary composite outcome in patients <75 years of age (HR: 0.80; 95% CI: 0.72-0.88). The protective association between early rhythm control and cardiovascular outcomes exhibited a linear decrease with advancing age, with declined benefits in patients ≥75 years of age (HR: 0.94; 95% CI: 0.87-1.03; P_interaction = 0.045). Trends toward lower risks of ischemic stroke (HR: 0.78; 95% CI: 0.67-0.90) and acute myocardial infarction (HR: 0.63; 95% CI: 0.41-0.97) were observed in the older adults. No significant differences in safety outcomes were found across different ages.

CONCLUSIONS

The beneficial association of early rhythm control with cardiovascular outcomes was attenuated with increasing age, with the larger benefits in younger patients <75 years of age. No differences were found by age in treatment-related safety outcomes.

Association of Light-Intensity Physical Activity With Mortality in the Older Population: A Nationwide Cohort Study

Background

There is a paucity of information about mortality related to light-intensity physical activity (LPA) in the older population. We examine the associations between physical activity and mortality, focusing on the effect of light-intensity physical activity and the dose-response relationship between physical activity and mortality.

Methods

We analyzed a total of 58,537 participants aged ≥ 65 years (mean age, 73.9 ± 5.8 years; male, 36.0%) in the Korean National Health Insurance Service database between 2009 and 2012. The Date of the end of follow-up was December 31, 2013. Individuals were divided into four categories according to physical activity intensity: totally sedentary (43.3%), LPA only (35.8%), LPA and moderate- to vigorous-intensity physical activity (MVPA) (16.3%), MVPA only (4.5%). Physical activity was quantified using standardized self-reported questionnaires which composed of the duration and frequency of physical activity.

Results

During a mean follow-up of 39.6 ± 14.0 months, 5,651 (9.7%) deaths occurred. Compared with totally sedentary individuals, those in the LPA only, LPA and MVPA, and MVPA only groups showed 26% [hazard ratio (HR) 0.74, 95% confidence interval (CI) 0.68–0.82], 27% (HR 0.73, 95% CI 0.63–0.84), and 34% (HR 0.66, 95% CI 0.54–0.79) lower all-cause mortality risk, showing an inverse relationship between physical activity intensity and mortality risk. In contrast, the LPA only, LPA and MVPA, and MVPA only groups represented a stronger inverse association with CV mortality (LPA: HR 0.76, 95% CI 0.62–0.92; LPA with MVPA: HR 0.74, 95% CI 0.55–0.999; MVPA, HR 0.57, 95% CI 0.37–0.87). Among participants performing LPA alone, participants performing less than the recommended dose of physical activity had lower all-cause mortality than those with sedentary activity (1–249 MET-min/week: HR 0.74, 95% CI 0.67–0.82, 250–499 MET-min/week: HR 0.65, 95% CI 0.59–0.72).

Conclusion

Physical activity, even low doses of LPA, was associated with reduced mortality risk in the elderly population. This study may motivate sedentary individuals to engage in any physical activity for mortality benefits.

Small extracellular vesicles derived from patients with persistent atrial fibrillation exacerbate arrhythmogenesis via miR-30a-5p

Small extracellular vesicles (sEVs) are nanometer-sized membranous vesicles that contribute to the pathogenesis of atrial fibrillation (AF). Here, we investigated the role of sEVs derived from patients with persistent AF in the pathophysiology of AF. First, we evaluated the pathological effects of sEVs derived from the peripheral blood of patients with persistent AF (AF-sEVs). AF-sEVs treatment reduced cell viability, caused abnormal Ca2+ handling, induced reactive oxygen species (ROS) production, and led to increased CaMKII activation of non-paced and paced atrial cardiomyocytes. Next, we analyzed the miRNA profile of AF-sEVs to investigate which components of AF-sEVs promote arrhythmias, and we selected six miRNAs that correlated with CaMKII activation. qRT-PCR experiment identified that miR-30a-5p was significantly downregulated in AF-sEVs, paced cardiomyocytes, and atrial tissues of patients with persistent AF. CaMKII was predicted by bioinformatics analysis as a miR-30a-5p target gene and validated by a dual luciferase reporter; hence, we evaluated the effects of miR-30a-5p on paced cardiomyocytes and validated miR-30a-5p as a pro-arrhythmic signature of AF-sEVs. Consequently, AF-sEVs-loaded with miR-30a-5p attenuated pacing-induced Ca2+-handling abnormalities, whereas AF-sEVs-loaded with anti-miR-30a-5p reversed the change in paced cardiomyocytes. Taken together, the regulation of CaMKII by miR-30a-5p revealed that miR-30a-5p is a major mediator for AF-sEVs-mediated AF pathogenesis. Accordingly, these findings suggest that sEVs derived from patients with persistent AF exacerbate arrhythmogenesis via miR-30a-5p.

Stroke and Systemic Thromboembolism according to CHA2DS2-VASc Score in Contemporary Korean Patients with Atrial Fibrillation

PURPOSE

The incidence of stroke and/or systemic thromboembolism (SSE) has not been properly evaluated in well-anticoagulated atrial fibrillation (AF) patients. This study investigated the incidence of SSE according to CHA₂DS₂-VASc score in contemporary well-anticoagulated Korean AF patients.

MATERIALS AND METHODS

From the prospective multicenter COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation (CODE-AF) registry, we identified 9503 patients with non-valvular AF (mean age, 68±8 years; female 35.5%) enrolled between June 2016 and May 2020 with eligible follow-up visits. Stroke incidence in the CODE-AF registry was compared with that in an oral anticoagulant (OAC)-naïve AF cohort from the Korean National Health Insurance database.

RESULTS

The usage rates of OACs and antiplatelet agents were 73.5% (non-vitamin K OACs, 56.4%; warfarin, 17.1%) and 23.8%, respectively. During a mean follow-up period of 26.3±9.6 months, 163 (0.78 per 100 person-years) patients had SSE. The incidence rate (per 100 person-years) of SSE was 0.77 in the total population, 0.26 in low-risk patients [CHA₂DS₂-VASc score 0 (male) or 1 (female)], and 0.88 in high-risk patients (CHA₂DS₂-VASc score ≥2). Contemporary AF patients had a stroke rate that was about one-fifth the stroke rate reported in a Korean OAC-naïve AF cohort. In this cohort, most risk factors for CHA₂DS₂-VASc score showed significant associations with SSE. Female sex was not associated with an increased risk of stroke/SSE in well-anticoagulated AF patients.

CONCLUSION

Contemporary AF patients have a stroke rate about one-fifth that in OAC-naïve AF patients and exhibit different stroke risk factors.

STUDY REGISTRATION

ClinicalTrials.gov (NCT02786095).

Compressed Deep Learning to Classify Arrhythmia in an Embedded Wearable Device

The importance of an embedded wearable device with automatic detection and alarming cannot be overstated, given that 15-30% of patients with atrial fibrillation are reported to be asymptomatic. These asymptomatic patients do not seek medical care, hence traditional diagnostic tools including Holter are not effective for the further prevention of associated stroke or heart failure. This is likely to be more so in the era of COVID-19, in which patients become more reluctant on hospitalization and checkups. However, little literature is available on this important topic. For this reason, this study developed efficient deep learning with model compression, which is designed to use ECG data and classify arrhythmia in an embedded wearable device. ECG-signal data came from Korea University Anam Hospital in Seoul, Korea, with 28,308 unique patients (15,412 normal and 12,896 arrhythmia). Resnets and Mobilenets with model compression (TensorFlow Lite) were applied and compared for the diagnosis of arrhythmia in an embedded wearable device. The weight size of the compressed model registered a remarkable decrease from 743 MB to 76 KB (1/10000), whereas its performance was almost the same as its original counterpart. Resnet and Mobilenet were similar in terms of accuracy, i.e., Resnet-50 Hz (97.3) vs. Mo-bilenet-50 Hz (97.2), Resnet-100 Hz (98.2) vs. Mobilenet-100 Hz (97.9). Here, 50 Hz/100 Hz denotes the down-sampling rate. However, Resnets took more flash memory and longer inference time than did Mobilenets. In conclusion, Mobilenet would be a more efficient model than Resnet to classify arrhythmia in an embedded wearable device.

Impact of Physical Activity on All-Cause Mortality According to Specific Cardiovascular Disease

Background

Patients with cardiovascular disease (CVD) tend to have higher mortality rates and reduced physical activity (PA). We aimed to evaluate the effect of PA on mortality in older adults with specific CVD.

Methods

We enrolled 68,223 participants (n = 23,871 with CVD, n = 44,352 without CVD) aged ≥65 years with available physical activity data between 2005 and 2012 from the Korean National Health Insurance Service of Korea-Senior database. CVD was defined as a history of ischemic stroke, transient ischemic attack, heart failure, myocardial infarction, and peripheral artery disease.

Results

Patients with CVD were older than those without CVD. Compared with the sedentary group, the physically active groups with and without CVD had a lower incidence and risk of all-cause death during a median follow up period of 42 (interquartile range 30–51) months. A 500 metabolic equivalent task-min/week increase in PA resulted in an 11% and 16% reduction in the risk of mortality in the non-CVD and CVD groups, respectively. With regard to specific CVDs, the risk of mortality progressively reduced with increasing PA in patients with heart failure or myocardial infarction. However, the reduction reached a plateau in patients with stroke or peripheral artery disease, but was significantly greater in patients with stroke (20% vs. without stoke, 11%, P_int = 0.006) or heart failure (13% vs. without heart failure, 11%; P_int = 0.045)

Conclusions

PA was associated with a reduced risk of all-cause mortality in older adults with and without CVD. The benefits of PA in patients with CVD, especially patients with stroke or heart failure, were greater than those without.

2021 Asia Pacific Heart Rhythm Society (APHRS) practice guidance on atrial fibrillation screening

In this paper, the Asia Pacific Heart Rhythm Society (APHRS) sought to provide practice guidance on AF screening based on recent evidence, with specific considerations relevant to the Asia-Pacific region. A key recommendation is opportunistic screening for people aged ≥65 years (all countries), with systematic screening to be considered for people aged ≥75 years or who have additional risk factors (all countries).

Association of rhythm control with incident dementia among patients with atrial fibrillation: a nationwide population-based cohort study

BACKGROUND

Atrial fibrillation (AF) increases the risk of dementia, and catheter ablation of AF may be associated with a lower risk of dementia. We investigated the association of a rhythm-control strategy for AF with the risk of dementia, compared with a rate-control strategy.

METHODS

This population-based cohort study included 41,135 patients with AF on anticoagulation who were newly treated with rhythm-control (anti-arrhythmic drugs or ablation) or rate-control strategies between 1 January 2005 and 31 December 2015 from the Korean National Health Insurance Service database. The primary outcome was all-cause dementia, which was compared using propensity score overlap weighting.

RESULTS

In the study population (46.7% female; median age: 68 years), a total of 4,039 patients were diagnosed with dementia during a median follow-up of 51.7 months. Rhythm control, compared with rate control, was associated with decreased dementia risk (weighted incidence rate: 21.2 versus 25.2 per 1,000 person-years; subdistribution hazard ratio [sHR] 0.86, 95% confidence interval [CI] 0.80-0.93). The associations between rhythm control and decreased dementia risk were consistently observed even after censoring for incident stroke (sHR 0.89, 95% CI 0.82-0.97) and were more pronounced in relatively younger patients and those with lower CHA2DS2-VASc scores. Among dementia subtypes, rhythm control was associated with a lower risk of Alzheimer's disease (sHR 0.86, 95% CI 0.79-0.95).

CONCLUSIONS

Among anticoagulated patients with AF, rhythm control was associated with a lower risk of dementia, compared with rate control. Initiating rhythm control in AF patients with fewer stroke risk factors might help prevent subsequent dementia.

Association of proteinuria and hypertension with incident atrial fibrillation in an elderly population: nationwide data from a community-based elderly cohort

OBJECTIVE

The excess risk of atrial fibrillation in relation to the presence of proteinuria associated with hypertension has not been well elucidated. We aimed to determine the effect of hypertension and/or proteinuria on the incidence of atrial fibrillation. Second, we evaluated whether the associations with temporal changes in proteinuria status on the incidence of atrial fibrillation.

METHODS AND RESULTS

A total of 85 434 participants with hypertension and 125 912 participants without hypertension with age at least 60 years from the Korea National Health Insurance Service-Senior cohort were included. Amongst controls (participants without proteinuria and hypertension), hypertension only, proteinuria only, and hypertension with proteinuria groups, the adjusted incidences of atrial fibrillation were 0.51, 0.69. 0.78 and 0.99 per 100 person-years, respectively after inverse probability of treatment weighting. Compared with controls, the weighted risks of atrial fibrillation in the hypertension only, proteinuria only and hypertension with proteinuria groups were increased by 37% (hazard ratio 1.37, 95% confidence interval, CI 1.30-1.44, P = 0.001), 55% (hazard ratio 1.55, 95% CI 1.28-1.88, P < 0.001), and 98% (hazard ratio 1.98, 95% CI 1.62-2.43, P < 0.001), respectively. Populations who had proteinuria in the first examination had an increased risk of atrial fibrillation even in the group whereby the proteinuria was resolved on the second examination (hazard ratio 1.36, 95% CI 1.12-2.31, P < 0.001). The presence of proteinuria in first and second analysis had the highest risk of incident atrial fibrillation (hazard ratio 1.61, 95% CI 1.12-2.31).

CONCLUSION

In conclusion, hypertension and/or proteinuria were associated with increased risk of atrial fibrillation, with the greatest risks when both are present. Proteinuria could be a useful factor for predicting atrial fibrillation development.

Association of Gender With Clinical Outcomes in a Contemporary Cohort of Patients With Atrial Fibrillation Receiving Oral Anticoagulants

We evaluated the relationship between biological sex and adverse clinical events in a contemporary atrial fibrillation (AF) cohort, mainly those taking direct oral anticoagulants, among patients with more-than-intermediate risk of stroke. Sex-based differences are noted in the outcomes of patients with AF who used anticoagulants, primarily vitamin K antagonist. The stroke or systemic embolism risk and major bleeding risk did not differ between the sexes, although women had a lower risk of all-cause mortality in contemporary anticoagulation for AF. Female may not be a risk factor for adverse clinical events associated with anticoagulation for AF.

Background and Objectives

In patients with atrial fibrillation (AF), females taking vitamin K antagonist are at higher risk of stroke or systemic embolism (SSE), bleeding and all-cause death than males. This study investigated the relationship between sex and adverse clinical events in a contemporary AF patient cohort taking anticoagulation.

Methods

This prospective multicenter AF registry study comprised 6,067 patients with AF (mean age, 70±9 years; men, 59%) with intermediate to high risk of stroke (CHA₂DS₂-VAscore ≥1) and receiving oral anticoagulation therapy. Adverse clinical outcomes, including SSE, bleeding, death were evaluated in patients stratified by sex and anticoagulation patterns.

Results

Women were older and used more direct oral anticoagulants (85% vs. 78%, p<0.001) than men. During a median (25^th and 75^th percentiles) follow-up of 30 (24, 38) months, the incidence rate and risk of SSE (0.7 in women vs. 0.7 in men per 100 person-years) and major bleeding (0.1 in women vs. 0.1 in men per 100 person-years) were not different between the sexes. However, women had a lower all-cause death rate (0.4 in women vs. 0.6 in men per 100 person-years, hazard ratio: 0.48, 95% confidence interval: 0.25–0.91, p=0.025) than men.

Conclusions

In contemporary anticoagulation for AF, SSE and major bleeding risks did not differ between sexes. However, women showed a lower risk of all-cause death rate than men, indicating that the use of oral anticoagulants for treating AF in females does not appear to be a risk factor for adverse clinical events.

Trial Registration

ClinicalTrials.gov Identifier: NCT02786095

The burden of undertreatment and non-treatment among patients with non-valvular atrial fibrillation and elevated stroke risk: a systematic review

OBJECTIVE

Global treatment guidelines recommend treatment with oral anticoagulants (OACs) for patients with non-valvular atrial fibrillation (NVAF) and an elevated stroke risk. However, not all patients with NVAF and an elevated stroke risk receive guideline-recommended therapy. A literature review and synthesis of observational studies were undertaken to identify the body of evidence on untreated and undertreated NVAF and the association with clinical and economic outcomes.

METHODS

An extensive search (1/2010-4/2020) of MEDLINE, the Cochrane Library, conference proceedings, and health technology assessments (HTAs) was conducted. Studies must have evaluated rates of nontreatment or undertreatment in NVAF. Nontreatment was defined as absence of OACs (but with possible antiplatelet treatment), while undertreatment was defined as treatment with only antiplatelet agents.

RESULTS

Sixteen studies met our inclusion criteria. Rates of nontreatment for patients with elevated stroke risk ranged from 2.0-51.1%, while rates of undertreatment ranged from 10.0-45.1%. The clinical benefits of anticoagulation were reported in the evaluated studies with reductions in stroke and mortality outcomes observed among patients treated with anticoagulants compared to untreated or undertreated patients. Adverse events associated with all bleeding types (i.e. hemorrhagic stroke, major bleeding or gastrointestinal hemorrhaging) were found to be higher for warfarin patients compared to untreated patients in real-world practice. Healthcare resource utilization was found to be lower among patients highly-adherent to warfarin compared to untreated patients.

CONCLUSIONS

Rates of nontreatment and undertreatment among NVAF patients remain high and are associated with preventable cardiovascular events and death. Strategies to increase rates of treatment may improve clinical outcomes.

Comparative Effectiveness of Early Rhythm Control Versus Rate Control for Cardiovascular Outcomes in Patients With Atrial Fibrillation

Background Rhythm control is associated with better cardiovascular outcomes than usual care among patients with recently diagnosed atrial fibrillation (AF). This study investigated the effects of rhythm control compared with rate control on the incidence of stroke, heart failure, myocardial infarction, and cardiovascular death stratified by timing of treatment initiation. Methods and Results We conducted a retrospective population-based cohort study including 22 635 patients with AF newly treated with rhythm control (antiarrhythmic drugs or ablation) or rate control in 2011 to 2015 from the Korean National Health Insurance Service database. Propensity overlap weighting was used. Compared with rate control, rhythm control initiated within 1 year of AF diagnosis decreased the risk of stroke. The point estimates for rhythm control initiated at selected time points after AF diagnosis are as follows: 6 months (hazard ratio [HR], 0.76; 95% CI, 0.66-0.87), 1 year (HR, 0.78; 95% CI, 0.66-0.93), and 5 years (HR, 1.00; 95% CI, 0.45-2.24). The initiation of rhythm control within 6 months of AF diagnosis reduced the risk of hospitalization for heart failure: 6 months (HR, 0.84; 95% CI, 0.74-0.95), 1 year (HR, 0.96; 95% CI, 0.82-1.13), and 5 years (HR, 2.88; 95% CI, 1.34-6.17). The risks of myocardial infarction and cardiovascular death did not differ between rhythm and rate control regardless of treatment timing. Conclusions Early initiation of rhythm control was associated with a lower risk of stroke and heart failure-related admission than rate control in patients with recently diagnosed AF. The effects were attenuated as initiating the rhythm control treatment later.

Increased risk of ischemic stroke and systemic embolism in hyperthyroidism-related atrial fibrillation: A nationwide cohort study

BACKGROUND

We aimed to evaluate the long-term risk of ischemic stroke/systemic embolism of hyperthyroidism-related AF.

METHODS

This retrospective population-based cohort study included records of 1,034,099 atrial fibrillation patients between 2005 and 2016 from the Korean National Health Insurance Service database. After exclusion, we identified 615,724 oral anticoagulation-naïve patients aged ≥18 years with new-onset non-valvular atrial fibrillation, of whom 20,773 had hyperthyroidism-related atrial fibrillation. After 3:1 propensity score matching, ischemic stroke and systemic embolism occurrences were compared between hyperthyroidism-related and non-hyperthyroidism-related ("nonthyroidal") atrial fibrillation patients.

RESULTS

After exclusion, we identified 615,724 oral anticoagulation-naïve AF patients of whom 20,773 had hyperthyroidism-related AF. Median follow-up duration was 5.9 years. Hyperthyroidism-related AF patients had significantly higher risks of ischemic stroke and systemic embolism than nonthyroidal AF patients (1.83 vs 1.62 per 100-person year, hazard ratio[HR], 1.13; 95% confidence interval[CI], 1.07 to 1.19; P < 0.001). This risk was 36% higher in hyperthyroidism-related than in nonthyroidal AF patients within 1 year of atrial fibrillation diagnosis (3.65 vs 2.67 per 100-person year, HR, 1.36; 95% CI, 1.24 - 1.50; P < 0.001). This difference was also observed in the CHA₂DS₂-VASc score subgroup analysis. The risk of ischemic stroke and systemic embolism significantly decreased in patients treated for hyperthyroidism (HR, 0.64; 95% CI, 0.58 to 0.70; P < 0.001).

CONCLUSIONS

Hyperthyroidism-related AF patients have high risks of ischemic stroke and systemic embolism like nonthyroidal AF, especially when initially diagnosed. This risk is reduced by treating hyperthyroidism.

Association of Physical Activity Level With Risk of Dementia in a Nationwide Cohort in Korea

IMPORTANCE

Current guidelines recommend 500 to 999 metabolic equivalent (MET)-minutes per week (MET-min/wk) of regular physical activity. However, evidence regarding the association between light-intensity physical activity (LPA) and dementia in older adults is inconsistent.

OBJECTIVE

To assess the association between physical activity and new-onset dementia, focusing on the dose-response association between physical activity and dementia and the association of LPA with the incidence of dementia.

DESIGN, SETTING, AND PARTICIPANTS

For this nationwide retrospective cohort study, we analyzed 62 286 participants aged 65 years or older without preexisting dementia who had available health checkup data from the Korean National Health Insurance Service database from January 2009 to December 2012. Participants were followed up until December 31, 2013, and data analysis was performed from July 2020 to January 2021.

EXPOSURES

Physical activity level was assessed using a standardized, self-reported questionnaire at baseline. Physical activity-related energy expenditure (in MET-min/wk) was calculated by summing the product of frequency, intensity, and duration.

MAIN OUTCOMES AND MEASURES

Incidence of dementia. Incidence rates were calculated by dividing the number of events by the person-time at risk (presented as the incidence per 1000 person-years). Hazard ratios (HRs) and 95% CIs for dementia were analyzed according to physical activity level. Competing risk regression was performed by using the Fine-Gray subdistribution hazard model, with mortality as the competing risk for dementia events. Multivariable regression models were constructed with adjustment for various patient characteristics. Incident dementia occurring 2 years after enrollment was assessed, and separate analyses included all follow-up periods. Restricted cubic spline curves were used to examine the association of continuous values of physical activity with dementia.

RESULTS

Among 62 286 participants, 60.4% were women, and the mean (SD) age was 73.2 (5.3) years. During a median follow-up of 42 months, 3757 participants (6.0%) developed dementia, and the overall incidence was 21.6 per 1000 person-years. Compared with inactive individuals (0 MET-min/wk), insufficiently active (1-499 MET-min/wk; mean, 284 MET-min/wk), active (500-999 MET-min/wk; mean, 675 MET-min/wk), and highly active participants (≥1000 MET-min/wk; mean, 1627 MET-min/wk) showed 10% (adjusted hazard ratio [HR], 0.90; 95% CI, 0.81-0.99), 20% (adjusted HR, 0.80; 95% CI, 0.71-0.92), and 28% (adjusted HR, 0.72; 95% CI, 0.60-0.83) reduced dementia risk, respectively. Thus, a progressive decrease in the adjusted HR of dementia was associated with increasing physical activity level, and a restricted cubic spline curve showed that this association started with a low amount of total physical activity. This association was consistent regardless of age, sex, and other comorbidities or after censoring for stroke. Compared with total sedentary behavior, even a low amount of LPA (1-299 MET-min/wk; mean, 189 MET-min/wk) was associated with reduced dementia risk (adjusted HR, 0.86; 95% CI, 0.74-0.99).

CONCLUSIONS AND RELEVANCE

In older adults, an increased physical activity level, including a low amount of LPA, was associated with a reduced risk of dementia. Promotion of LPA might reduce the risk of dementia in older adults.

2021 Focused update of the 2017 consensus guidelines of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The Practice Guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of AF Better Care (ABC) pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian patients with AF with single 1 stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" (COVID-19) pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

Mortality among ischemic and nonischemic heart failure patients with a primary implantable cardioverter-defibrillator

BACKGROUND

The efficacy of implantable cardioverter defibrillators (ICDs) for primary prevention is controversial in patients with nonischemic heart failure (HF). We evaluated the mortality and predictors of mortality in patients with prophylactic ICD implantation for ischemic and nonischemic HF.

METHODS

From 2008 to 2017, 1097 patients (667, nonischemic HF and 430, ischemic HF) who underwent prophylactic ICD implantation, were identified from the Korean National Health Insurance Service database. We used propensity score overlap weighting to correct the differences between two groups.

RESULTS

Those with ischemic HF were older (67.0 ± 10.1 vs 61.8 ± 14.2 years), more often male (71.4% vs 63.7%), and had more comorbidities than patients with nonischemic HF. During a median follow-up of 37.3 months (interquartile range [IQR], 14.2-53.8 months), all-cause mortality was higher in unweighted patients with ischemic HF than in those with nonischemic HF (10.9 vs 6.4 per 100 person-years; hazard ratio [HR], 1.74; 95% confidence interval [CI], 1.38-2.20; P < .001). However, after weighting, the annual all-cause mortality rate was similar in both groups (9.5 vs 8.8 per 100 person-years), with no significant difference in the risk of all-cause mortality (HR, 1.08; 95% CI, 0.68-1.71; P = .755). Older age and chronic kidney disease were independent predictors of all-cause mortality in both groups. There was no significant difference in cardiac and noncardiac mortality between the weighted nonischemic and ischemic HF groups.

CONCLUSIONS

The all-cause, cardiac, and noncardiac mortality rates were similar between patients with nonischemic and ischemic HF who underwent prophylactic ICD implantation.

Impact of abdominal obesity on outcomes of catheter ablation in Korean patients with atrial fibrillation

BACKGROUND

Effects of abdominal obesity on outcomes of atrial fibrillation (AF) ablation remains ill-defined. Here, we evaluated the impact of abdominal obesity on the long-term efficacy and safety of catheter AF ablation among Korean patients.

METHODS

We utilised the Korean National Health Insurance Service database to identify patients who underwent AF ablation. Abdominal obesity was defined as waist circumference ≥90 cm (males) and ≥85 cm (females). The primary endpoint was AF recurrence and secondary endpoints were ischaemic stroke, intracranial haemorrhage and death. Additionally, safety endpoints of peri-procedural complications were studied.

RESULTS

Among 5397 patients (median age 58 [IQR 51-65] years; 23.6% females), abdominal obesity was present in 1759 (32.6%). The rate of AF recurrence was not statistically different between the groups at 1-year (10.3 vs 8.7 events/100-PYs, P = .078), though abdominal obesity was associated with significantly higher rates of AF recurrence at 3-year (7.6 vs 6.3 events/100-PYs, P = .008) and 6-year (6.3 vs 5.2 events/100-PYs, P = .004) follow-ups. Kaplan-Meier survival analysis found significantly higher rates of AF recurrence in patients with obesity based on body mass index (BMI) and waist circumference (log-rank for trend P = .006). Using multivariable regression analysis, obesity by both BMI and waist circumference was an independent predictor for AF recurrence (HR 1.21 [95% CI, 1.05-1.40]), after accounting for other risk factors. There was a trend for increased rates of ischaemic stroke at 3-year and 6-year follow-ups in patients with abdominal obesity. Furthermore, this group of patients had a greater rate of intracranial haemorrhage. All-cause death was comparable between both groups. Total peri-procedural complications were not associated with abdominal obesity.

CONCLUSION

Abdominal obesity as indicated by waist circumference was associated with a greater burden of concomitant diseases and an independent risk factor for long-term redo AF intervention following catheter ablation but had no effects on total peri-procedural complications.

Lower dementia risk with anticoagulation and ablation in patients with atrial fibrillation

Atrial fibrillation (AF), the most common cardiac arrhythmia in the elderly population, has been associated with an impairment of cognitive function and an increased risk of dementia. Even though there does not appear to be solid evidence that any specific treatment prevents or delays AF-associated cognitive decline, evidence is accumulating regarding the possible treatment strategies for preventing dementia. Oral anticoagulation, especially non-vitamin K antagonist oral anticoagulants rather than warfarin use, has been suggested to be associated with reduced risk of dementia. Successfully maintaining sinus rhythm using catheter ablation might be also helpful in preventing subsequent dementia in patients with AF. In this review, we critically appraise the proposed treatment strategies for preventing AF-associated cognitive decline.

Association of proteinuria and incident atrial fibrillation in patients with diabetes mellitus: a population-based senior cohort study

Diabetes mellitus (DM) is considered an independent risk factor for atrial fibrillation (AF). The excess risk in relation to the presence of proteinuria has not been well elucidated. Our aim was to determine the association between the incidence of AF and proteinuria in diabetic population. A total of 240,499 individuals aged ≥ 60 years from the Korea National Health Insurance Service-Senior cohort from 2004 to 2014 were included. 4.2% of individuals with DM and 3.7% of controls were diagnosed with AF during a median follow-up period of 7.2 years. Amongst controls (participants without proteinuria and DM), DM only, proteinuria only, and DM with proteinuria groups, the crude incidences of AF were 0.58, 0.70, 0.96, 1.24 per 100 person-years respectively. Compared with controls, the weighted risk of AF was increased by 11% (hazard ratio = 1.11, 95% confidence interval = 1.02-1.20, P = .001), 48% (hazard ratio = 1.48, 95% confidence interval = 1.30-1.69, P < .001), and 66% (hazard ratio = 1.66, 95% confidence interval = 1.26-2.18, P < .001) in the DM only, proteinuria only, and DM with proteinuria groups, respectively (P for trend < .001). Degree of proteinuria in diabetic patients was associated with a significantly higher rate of incident AF in dose dependent manner. Thus, assessing proteinuria by a simple urine dipstick test could provide a useful adjunct to risk assessment for AF in elderly population with DM.

Risk of sick sinus syndrome in patients diagnosed with atrial fibrillation: A population-based cohort

BACKGROUND

Sinoatrial node dysfunction and atrial fibrillation (AF) frequently coexist and interact with each other, often to initiate and perpetuate each other.

OBJECTIVE

To determine the effect of AF on the incidence and risk of sick sinus syndrome (SSS).

METHODS

The association of incident AF with the development of incident SSS was assessed from 2004 to 2014 in 302 229 SSS- and pacemaker-free subjects aged ≥60 years in the Korea National Health Insurance Service-Senior cohort.

RESULTS

During an observation period of 1 854 800 person-years, incident AF was observed in a total of 12 797 subjects (0.69%/year). The incidence of SSS was 3.4 and 0.2 per 1000 person-years in the propensity score-matched incident AF and no-AF groups, respectively. After adjustment, the significantly increased risk of SSS was observed in the incident AF group, with a hazard ratio (HR) of 13.4 (95% confidence interval [CI]: 8.4-21.4). This finding was consistently observed after censoring for heart failure (HR: 16.0; 95% CI: 9.2-28.0) or heart failure/myocardial infarction (HR: 16.6; 95% CI: 9.3-29.7). Incident AF also was associated with an increased risk of pacemaker implantation related with both SSS (HR: 21.8; 95% CI: 8.7-18.4) and atrioventricular (AV) block (HR: 9.5; 95% CI: 4.9-18.4). These results were consistent regardless of sex and comorbidities.

CONCLUSION

Incident AF was associated with more than 10 times increased risk of SSS in an elderly population regardless of comorbidities. The risk of pacemaker implantations related with both sinus node dysfunction and AV block was increased in the elderly population with incident AF.

Frailty and the Effect of Catheter Ablation in the Elderly Population With Atrial Fibrillation - A Real-World Analysis

BACKGROUND

It is unclear whether catheter ablation is beneficial for frail elderly patients with atrial fibrillation (AF). This study evaluated the effect of ablation on outcomes in frail elderly patients with AF.

METHODS AND RESULTS

From the Korean National Health Insurance Service database, 194,928 newly diagnosed AF patients were treated with ablation or medical therapy (rhythm or rate control) between 2005 and 2015. Among these patients, the study included 1,818 (ablation; n=119) frail and 1,907 (ablation; n=230) non-frail elderly (≥75 years) patients. Propensity score matching was used to correct for differences between groups. During 28 months (median) follow up, the risk of all-cause death, composite outcome (all-cause death, heart failure admission, stroke/systemic embolism, and sudden cardiac arrest), and each outcome did not change after ablation in frail elderly patients. However, in non-frail elderly patients, ablation was associated with a lower risk of all-cause death (3.5 and 6.2 per 100 person-years; hazard ratio [HR] 0.48; 95% confidence interval [CI] 0.30-0.79; P=0.004), and composite outcome (6.9 and 11.2 per 100 person-years; HR 0.54; 95% CI 0.38-0.75; P<0.001).

CONCLUSIONS

Ablation may be associated with a lower risk of death and composite outcome in non-frail elderly, but the beneficial effect of ablation was not significant in frail elderly patients with AF. The effect of frailty on the outcome of ablation should be evaluated in further studies.