2025 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2025 AHA Statistical Update is the product of a full year's worth of effort in 2024 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. This year's edition includes a continued focus on health equity across several key domains and enhanced global data that reflect improved methods and incorporation of ≈3000 new data sources since last year's Statistical Update.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Impact of lifestyle risk factors on atrial fibrillation: Mechanisms and prevention approaches - A narrative review

Both the development and progression of atrial fibrillation (AF) are affected by a range of modifiable lifestyle risk factors. These key modifiable risk factors encompass obesity, hypertension, hypercholesterolemia, diabetes mellitus, smoking, chronic obstructive pulmonary disease, alcohol consumption, exercise, sedentary lifestyle and obstructive sleep apnoea. These lifestyle-dependent factors rarely exist in isolation, but rather exist together, exerting a complex influence on the development of AF. This comprehensive review elucidates the interplay and interdependency of these lifestyle factors in the arrhythmogenesis of AF, by exploring their role in AF substrate formation, modulating properties and triggering mechanisms. We emphasize the importance of targeted prevention strategies by discussing available literature on the effectiveness of treatment strategies targeting multiple risk factors. Additionally, the clinical impacts of integrated care, nurse-led care and mobile health are discussed in the context of lifestyle improvement. These management strategies have favourable applicability in both paroxysmal and persistent AF, and are also beneficial for patients receiving AF ablation. Despite the challenges accompanying lifestyle and prevention strategies, substantial benefits are apparent, such as improved quality of life and better ablation outcomes. This review further emphasizes the essential nature of awareness of appropriate lifestyle modifications as fundamental pillars in the management of individuals with AF.

The impact of lifestyle factors on atrial fibrillation

Atrial fibrillation (AF), with its significant associated morbidity and mortality contributes to significant healthcare utilisation and expenditure. Given its progressively rising incidence, strategies to limit AF development and progression are urgently needed. Lifestyle modification is a potentially potent but underutilised weapon against the AF epidemic. The purpose of this article is to review the role of lifestyle factors as risk factors for AF, outline potential mechanisms of pathogenesis and examine the available evidence for lifestyle intervention in primary and secondary AF prevention. It will also highlight the need for investment by physicians, researchers, health services and governments in order to facilitate delivery of the comprehensive, multidisciplinary AF care that is required to manage this complex and multifactorial disease.

Leisure-time physical activity and the incidence of atrial fibrillation in senior adults: a prospective cohort study

OBJECTIVE

Whether physical activity could reduce the risk of atrial fibrillation (AF) remains unclear. This study was to investigate the relationship of leisure-time physical activity (LTPA) with AF incidence among Chinese older adults.

METHODS

A total of 3253 participants aged ≥60 years from the Guangzhou Heart Study were successfully followed between March 2018 and September 2019. LTPA was assessed using a modified Global Physical Activity Questionnaire. AF was ascertained by 12-lead electrocardiograms, 24-hour single-lead Holter and clinical examination. The Cox proportional hazards model was used to the estimate hazard ratio (HR) and 95% confidence interval (CI) after adjustment for confounders, and the population-attributable fraction (PAF) was estimated.

RESULTS

A total of 76 (2.34%) new-onset cases of AF were identified during a median of 31.13 months of follow-up. After adjustment for confounders, subjects who had LTPA at least 10.0 metabolic equivalent (MET)-hours/week had a 55% lower risk of developing AF (HR: 0.45, 95%CI: 0.25-0.81), and at least 20 MET-hours/week reduced the risk by 45% (HR: 0.55, 95%CI: 0.34-0.92). At least 11% (PAF: 11%, 95%CI: 0%-20%) or 14% (PAF: 14%, 95%CI: 0%-26%) of AF cases could be avoided, respectively, if the subjects do LTPA at least 10 MET-hours/week or 20 MET-hours/week. A significant exposure-response trend was also observed between LTPA and AF risk (Plinear-trend = 0.002). For a specific LTPA, doing housework was associated with a 43% reduced risk, while engaging in ball games was associated with an increased risk.

CONCLUSION

This prospective cohort study indicated that a higher LTPA volume was associated with a lower AF risk in Chinese older adults.

Leisure-time and occupational physical activity and risk of cardiovascular disease incidence: a systematic-review and dose-response meta-analysis of prospective cohort studies

BACKGROUND AND OBJECTIVE

Physical activity has benefits for the cardiovascular system, however, what levels and types of activity provide optimal cardiovascular health is unclear. We aimed to determine the level of physical activity that has the most benefits against cardiovascular diseases (CVD).

METHODS

PubMed, Scopus, and Web of Science were searched for prospective cohort studies on leisure-time (LTPA) or occupational physical activity (OPA) as the exposure and major types of CVD (total CVD, coronary heart disease [CHD], stroke, and atrial fibrillation [AF]) incidence as the outcome. Risk of bias of studies was evaluated using the ROBINS-I tool. Summary hazard ratios (HR) were calculated using random-effects pairwise model.

RESULTS

A total of 103 studies were included in the analysis. The highest versus the lowest LTPA was associated with a lower risk of overall CVD (HR = 0.81; 95% CI: 0.77-0.86), CHD (HR = 0.83; 0.79-0.88), and stroke (HR = 0.83; 0.79-0.88), but not AF (HR = 0.98; 0.92-1.05). Linear dose-response analyses showed a 10%, 12%, 9%, and 8% risk reduction in CVD, CHD, stroke, and AF incidence, respectively, for every 20 MET-hours/week increase in LTPA. In nonlinear dose-response analyses, there were inverse associations up to 20 MET-hours/week with 19% and 20% reduction in CVD and CHD risk, and up to 25 MET-hours/week with 22% reduction in stroke, with no further risk reduction at higher LTPA levels. For AF, there was a U-shaped nonlinear association with the maximum 8% risk reduction at 10 MET-hours/week of LTPA. Higher levels of OPA were not associated with risk of CVD, CHD, stroke, or AF.

CONCLUSIONS

Overall, results showed an inverse dose-response relationship between LTPA and risk of CVD, CHD, stroke, and AF. Running was the most beneficial LTPA but the risk was similar among various LTPA intensities. OPA showed no benefits in total or any type of CVD.

Lifestyle Medicine: An Antidote to Cardiovascular Diseases

Despite numerous advances in basic understanding of cardiovascular disease pathophysiology, pharmacology, therapeutic procedures, and systems improvement, there hasn't been much decline in heart disease related mortality in the US since 2010. Hypertension and diet induced risk continue to be the leading causes of cardiovascular morbidity. Even with the excessive mortality associated with the COVID-19 pandemic, in 2020, heart disease remained the leading cause of death. Given the degree of disease burden, morbidity, and mortality, there is an urgent need to redirect medical professionals' focus towards prevention through simple and cost effective lifestyle strategies. However, current practice paradigm and financial compensation systems are mainly centered disease management and not health promotion. For example, the financial value placed on 3-10 min smoking cessation counseling (.24RVUs) is 47-fold lower than an elective PCI (11.21 RVUs). The medical community seems to be enamored with the latest and greatest technology, new devices, and surgical procedures. What if the greatest technology of all was simply the way we live every day? Perhaps when this notion is known by enough, we will switch to this lifestyle medicine technology to prevent disease in the first place.

2024 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2024 AHA Statistical Update is the product of a full year's worth of effort in 2023 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. The AHA strives to further understand and help heal health problems inflicted by structural racism, a public health crisis that can significantly damage physical and mental health and perpetuate disparities in access to health care, education, income, housing, and several other factors vital to healthy lives. This year's edition includes additional global data, as well as data on the monitoring and benefits of cardiovascular health in the population, with an enhanced focus on health equity across several key domains.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Atrial fibrillation: comorbidities, lifestyle, and patient factors

Modern anticoagulation therapy has dramatically reduced the risk of stroke and systemic thromboembolism in people with atrial fibrillation (AF). However, AF still impairs quality of life, increases the risk of stroke and heart failure, and is linked to cognitive impairment. There is also a recognition of the residual risk of thromboembolic complications despite anticoagulation. Hence, AF management is evolving towards a more comprehensive understanding of risk factors predisposing to the development of this arrhythmia, its' complications and interventions to mitigate the risk. This review summarises the recent advances in understanding of risk factors for incident AF and managing these risk factors. It includes a discussion of lifestyle, somatic, psychological, and socioeconomic risk factors. The available data call for a practice shift towards a more individualised approach considering an increasingly broader range of health and patient factors contributing to AF-related health burden. The review highlights the needs of people living with co-morbidities (especially with multimorbidity), polypharmacy and the role of the changing population demographics affecting the European region and globally.

Lifestyle changes in atrial fibrillation management and intervention

Atrial fibrillation (AF) is one of the most common arrhythmias in adults, and its continued rise in the United States is complicated by the increased incidence and prevalence of several AF risk factors, such as obesity, physical inactivity, hypertension, obstructive sleep apnea, diabetes mellitus, coronary artery disease, and alcohol, tobacco, or caffeine use. Lifestyle and risk factor modification has been proposed as an additional pillar of AF therapy, added to rhythm control, rate control, and anticoagulation, to reduce AF burden and risk. Although emerging evidence largely supports the integration of lifestyle and risk factor management in clinical practice, randomized clinical trials investigating the long-term sustainability and reproducibility of these benefits remain sparse. The purpose of this review is to discuss potentially reversible risk factors on AF, share evidence for the impact on AF by modification of these risk factors, and then provide an overview of the effects of reversing or managing these risk factors on the success of various AF management strategies, such as antithrombotic, rate control, and rhythm control therapies.

Obesity and atrial fibrillation: Prevalence, pathogenesis, and prognosis

The prevalence of atrial fibrillation (AF) and obesity are rising significantly. There is a shared association between these conditions with obesity predisposing individuals to a number of shared risk factors. In addition, obesity in itself has been shown to cause changes to the structure, function and hemodynamics of the heart. There is evidence to show that weight-loss has significant impact on AF symptoms, burden and more recently the potential to reverse the type of AF. Through risk factor management and in the case of morbid obesity, bariatric surgery, there is an improved prognosis for patients with AF and obesity. In this paper we provide a review of the current data on obesity and AF prevalence, pathogenesis and prognosis.

Atrial Fibrillation Occurring During Acute Hospitalization: A Scientific Statement From the American Heart Association

Acute atrial fibrillation is defined as atrial fibrillation detected in the setting of acute care or acute illness; atrial fibrillation may be detected or managed for the first time during acute hospitalization for another condition. Atrial fibrillation after cardiothoracic surgery is a distinct type of acute atrial fibrillation. Acute atrial fibrillation is associated with high risk of long-term atrial fibrillation recurrence, warranting clinical attention during acute hospitalization and over long-term follow-up. A framework of substrates and triggers can be useful for evaluating and managing acute atrial fibrillation. Acute management requires a multipronged approach with interdisciplinary care collaboration, tailoring treatments to the patient's underlying substrate and acute condition. Key components of acute management include identification and treatment of triggers, selection and implementation of rate/rhythm control, and management of anticoagulation. Acute rate or rhythm control strategy should be individualized with consideration of the patient's capacity to tolerate rapid rates or atrioventricular dyssynchrony, and the patient's ability to tolerate the risk of the therapeutic strategy. Given the high risks of atrial fibrillation recurrence in patients with acute atrial fibrillation, clinical follow-up and heart rhythm monitoring are warranted. Long-term management is guided by patient substrate, with implications for intensity of heart rhythm monitoring, anticoagulation, and considerations for rhythm management strategies. Overall management of acute atrial fibrillation addresses substrates and triggers. The 3As of acute management are acute triggers, atrial fibrillation rate/rhythm management, and anticoagulation. The 2As and 2Ms of long-term management include monitoring of heart rhythm and modification of lifestyle and risk factors, in addition to considerations for atrial fibrillation rate/rhythm management and anticoagulation. Several gaps in knowledge related to acute atrial fibrillation exist and warrant future research.

A focus group study to inform design of a symptom management intervention for adults with atrial fibrillation

Background

Current symptom management approaches for patients with atrial fibrillation (AF) focus on addressing heart rhythm and do not include management of behavioral or emotional contributors to symptom manifestation or severity.

Objective

To inform content development of a digitally delivered AF symptom self-management program by exploring patients’ experiences of the impact of AF symptoms and their perspectives on behavioral approaches to symptom management.

Methods

This was a qualitative study of 3 focus groups composed of adults living with symptomatic AF. Group transcripts underwent thematic content analysis to identify themes and subthemes. Themes were matched to available self-management strategies that could be adapted for use in a digitally delivered AF symptom self-management program.

Results

Six major themes (with subthemes) were identified: symptoms (anxiety, fatigue, stress/other negative emotions, AF-specific symptoms, heart rhythm); social aspects (social impact, social support); AF treatments (medication, procedures); health behaviors (sleep, physical activity, hydration, breathing/mindfulness/relaxation); positive emotions; and AF education and information gathering. Symptom self-management strategies were identified that could be used to address these symptom-related themes.

Conclusion

Patients with AF reported a wide range of emotional, physical, and social impacts of the condition. They endorsed attempts to self-manage symptoms and an interest in learning more about how to effectively self-manage. Findings indicate the potential for a digital self-management program to address existing gaps in AF symptom–related care.

Association Between Changes in Physical Activity and New-Onset Atrial Fibrillation After ICD/CRT-D Implantation

Background: Changes in physical activity (PA) after implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillators (CRT-D) implantation were unknown. The association of PA changes with new-onset atrial fibrillation (AF), cardiac death and all-cause mortality was unclear in patients at high risk of sudden cardiac death.

Methods: Patients receiving ICD/CRT-D implantation from SUMMIT registry were retrospectively analyzed. Changes in PA were considered from baseline status to 1 year after implantation. New-onset AF was defined as the first atrial high-rate episode ≥1% of the daily AF burden detected after implantation.

Results: Over a mean follow-up of 50.3 months, 124 new-onset AF events (36.2%), 61 cardiac deaths (17.8%), and 87 all-cause deaths (25.4%) were observed in 343 patients with ICD/CRT-D implantation. PA at 1 year after implantation was increased compared with PA at baseline (11.97 ± 5.83% vs. 10.82 ± 5.43%, P = 0.008), and PA at 1 year was improved in 210 patients (61.2%). Per 1% decrease in PA was associated with 12.4, 18.3, and 14.3% higher risks of new-onset AF, cardiac death and all-cause mortality, regardless of different baseline characteristics. Patients with decreased PA had 2-fold risks of new-onset AF (hazard ratio [HR] = 1.972, 95% confidence interval [CI]: 1.352–2.877, P < 0.001) as high as those with unchanged/increased PA. Decreased PA was an independent risk factor for cardiac death (HR = 3.358, 95% CI: 1.880–5.996, P < 0.001) and all-cause mortality (HR = 2.803, 95% CI:1.732–4.535, P < 0.001).

Conclusion: PA decrease after ICD/CRT-D implantation is associated with a higher incidence of new-onset AF, resulting in worsened outcomes in cardiac death and all-cause mortality.

Exercising immune cells: The immunomodulatory role of exercise on atrial fibrillation

Exercise training is generally beneficial for cardiovascular health, improving stroke volume, cardiac output, and aerobic capacity. Despite these benefits, some evidence indicates that endurance training may increase the risk of atrial fibrillation (AF), particularly in highly trained individuals. Among multiple mechanisms, autonomic tone changes and atrial remodeling have been proposed as main contributors for exercise-induced AF. However, the contribution of local and systemic immunity is poorly understood in the development of atrial arrhythmogenic substrates. Here we aim to update the field of immunomodulation in the context of exercise and AF by compiling and reconciling the most recent evidence from preclinical and human studies and rationalize the applicability of "lone" AF terminology in athletes.

Atrial Fibrillation (Part 1): Pathophysiology, Risk Factors, and Therapeutic Basis

A fibrilação atrial é a arritmia sustentada mais comum na prática clínica com predileção pelas faixas etárias mais avançadas. Com o envelhecimento populacional, as projeções para as próximas décadas são alarmantes. Além de sua importância epidemiológica, a fibrilação atrial é destacada por suas repercussões clínicas, incluindo fenômenos tromboembólicos, hospitalizações e maior taxa de mortalidade. Seu mecanismo fisiopatológico é complexo, envolvendo uma associação de fatores hemodinâmicos, estruturais, eletrofisiológicos e autonômicos. Desde os anos 1990, o estudo Framingham em análises multivariadas já demonstrou que, além da idade, a presença de hipertensão, diabetes, insuficiência cardíaca e doença valvar é preditor independente dessa normalidade do ritmo. Entretanto, recentemente, vários outros fatores de risco estão sendo implicados no aumento do número de casos de fibrilação atrial, tais como sedentarismo, obesidade, anormalidades do sono, tabagismo e uso excessivo de álcool. Além disso, as mudanças na qualidade de vida apontam para uma redução na recorrência de fibrilação atrial, tornando-se uma nova estratégia para o tratamento de excelência dessa arritmia cardíaca. A abordagem terapêutica envolve um amplo conhecimento do estado de saúde e hábitos do paciente, e compreende quatro pilares principais: mudança de hábitos de vida e tratamento rigoroso de fatores de risco; prevenção de eventos tromboembólicos; controle da frequência; e controle do ritmo. Pela dimensão de fatores envolvidos no cuidado ao paciente portador de fibrilação atrial, ações integradas com equipes multiprofissionais estão associadas aos melhores resultados clínicos.

Physical activity and risk of atrial fibrillation in the general population: meta-analysis of 23 cohort studies involving about 2 million participants

Regular physical activity is well established to be associated with reduced risk of cardiovascular disease outcomes. Whether physical activity is associated with the future risk of atrial fibrillation (AF) remains a controversy. Using a systematic review and meta-analysis of published observational cohort studies in general populations with at least one-year of follow-up, we aimed to evaluate the association between regular physical activity and the risk of AF. Relevant studies were sought from inception until October 2020 in MEDLINE, Embase, Web of Science, and manual search of relevant articles. Extracted relative risks (RRs) with 95% confidence intervals (CIs) for the maximum versus the minimal amount of physical activity groups were pooled using random-effects meta-analysis. Quality of the evidence was assessed by GRADE. A total of 23 unique observational cohort studies comprising of 1,930,725 participants and 45,839 AF cases were eligible. The pooled multivariable-adjusted RR (95% CI) for AF comparing the most physically active versus the least physically active groups was 0.99 (0.93–1.05). This association was modified by sex: an increased risk was observed in men: 1.20 (1.02–1.42), with a decreased risk in women: 0.91 (0.84–0.99). The quality of the evidence ranged from low to moderate. Pooled observational cohort studies suggest that the absence of associations reported between regular physical activity and AF risk in previous general population studies and their aggregate analyses could be driven by a sex-specific difference in the associations – an increased risk in men and a decreased risk in women.

Systematic review registration: PROSPERO 2020: CRD42020172814

Self-reported physical activity and atrial fibrillation risk: A systematic review and meta-analysis

BACKGROUND

Although physical activity (PA) is an important component of cardiovascular disease prevention and treatment, its role in atrial fibrillation (AF) risk is less well established.

OBJECTIVE

The purpose of this study was to systematically summarize the evidence pertaining to the relationship of PA and risk of AF.

METHODS

We searched the PubMed and Embase databases for prospective cohort studies reporting the risk of AF associated with a specific PA volume through March 2020. From each study, we extracted the risk associated with a given PA level, in comparison with insufficiently active ("inactive") individuals. The reported risk was normalized to metabolic equivalent of task (MET)-minutes per week. A random-effects meta-analysis was used to compare AF risk between those who met and those who did not meet PA recommendations (450 MET-minutes per week), and a dose-response analysis between the level of PA and the risk of AF was performed.

RESULTS

Fifteen studies reporting data from 1,464,539 individuals (median age 55.3 years; 51.7% female) were included. Individuals achieving guideline-recommended level of PA had a significantly lower risk of AF (hazard ratio 0.94; 95% confidence interval 0.90-0.97; P = .001). Dose-response analysis showed that PA levels up to 1900 MET-minutes per week were associated with a lower risk of AF, with less certainty beyond that level.

CONCLUSION

PA at guideline-recommended levels and above are associated with a significantly lower AF risk. However, at 2000 MET-minutes per week and beyond, the benefit is less clear.

Association between cardiorespiratory fitness, obesity, and incidence of atrial fibrillation

BACKGROUND

The interaction between cardiorespiratory fitness (CRF) and incidence of atrial fibrillation (AF) and the interaction between obesity and incidence of AF have been explored separately. Therefore, we evaluated the association between CRF, body mass index (BMI), and risk of developing AF in a cohort of middle-aged and older US Veterans.

METHODS

Symptom limited exercise tests (ETT) were conducted among 16,397 Veterans (97% male) from January 9,1987 to December 31,2017. No history of AF was evident at the time of the ETTs. CRF was expressed as quartiles of peak metabolic equivalents (METs) achieved within each age decile. Weight status was classified as normal (BMI < 25 kg/m2), overweight (BMI 25-30 kg/m2), obese (BMI 30-35 kg/m2), or severely obese (BMI > 35 kg/m2). Multivariable Cox proportional hazards regression models were used to compare the association between BMI, CRF categories, and incidence of AF.

RESULTS

Over a median follow-up of 10.7 years, 2,155 (13.1%) developed AF. Obese and severely obese subjects had 13% and 32% higher risks for incidence of AF, respectively, vs. normal weight subjects. Overweight and obese subjects in the most fit quartile had 50% decline in AF risk compared to the least-fit subjects. Severely obese subjects had marked increases in AF risk (~50-60%) regardless of fitness level. Risk of developing AF increases with higher BMI and lower CRF.

CONCLUSION

Improving CRF should be advocated when assessing those at risk for developing AF.

High fitness might be associated with the development of new-onset atrial fibrillation in obese non-athletic adults

BACKGROUND

Data on the association between AF and fitness are conflicting.

OBJECTIVES

The aim of this analysis was to investigate the association between fitness, obesity and incidence of atrial fibrillation (AF) among apparently healthy non-athlete adults.

METHODS

We investigated 20 410 self-referred subjects who were annually screened in a tertiary medical centre. All subjects were free of AF and completed maximal exercise stress test according to the Bruce protocol at baseline. Fitness was categorised into age- and sex-specific quintiles (Q) according to the treadmill time. Subjects were categorised to low (Q1-Q2) and high fitness (Q3-5) groups. The primary end point was new-onset AF during follow-up.

RESULTS

Mean age was 48 ± 10 years and 72% were men. A total of 463 (2.3%) events occurred during an average follow-up of 8 ± 5 years corresponding to an AF event rate of 0.3% per person year. Univariate and multivariate models showed that AF risk was similar in both fitness groups. However, AF event rate was 0.55% per person year among high fitness obese subjects, compared with 0.31% for low fitness obese subjects (P < .01). Subgroup interaction analysis showed that AF risk is obesity-dependent, such that in the obese group (≥30 kg/m² ) high fitness was independently associated with a significant 79% increased AF risk (95% CI 1.15-2.78; P = .01), whereas among non-obese subjects the rate of events was similar between both fitness groups (P for interaction = (.02)).

CONCLUSIONS

Our findings suggest that high fitness might be associated with increased AF risk among obese subjects.

Lifestyle and Risk Factor Modification for Reduction of Atrial Fibrillation: A Scientific Statement From the American Heart Association

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is associated with substantial morbidity, mortality, and healthcare use. Great strides have been made in stroke prevention and rhythm control strategies, yet reducing the incidence of AF has been slowed by the increasing incidence and prevalence of AF risk factors, including obesity, physical inactivity, sleep apnea, diabetes mellitus, hypertension, and other modifiable lifestyle-related factors. Fortunately, many of these AF drivers are potentially reversible, and emerging evidence supports that addressing these modifiable risks may be effective for primary and secondary AF prevention. A structured, protocol-driven multidisciplinary approach to integrate lifestyle and risk factor management as an integral part of AF management may help in the prevention and treatment of AF. However, this aspect of AF management is currently underrecognized, underused, and understudied. The purpose of this American Heart Association scientific statement is to review the association of modifiable risk factors with AF and the effects of risk factor intervention. Implementation strategies, care pathways, and educational links for achieving impactful weight reduction, increased physical activity, and risk factor modification are included. Implications for clinical practice, gaps in knowledge, and future directions for the research community are highlighted.

Physical activity, cardiorespiratory fitness, and cardiovascular outcomes in individuals with atrial fibrillation: the HUNT study

AIMS

Atrial fibrillation (AF) confers higher risk of mortality and morbidity, but the long-term impact of physical activity (PA) and cardiorespiratory fitness (CRF) on outcomes in AF patients is unknown. We, therefore, examined the prospective associations of PA and estimated CRF (eCRF) with all-cause mortality, cardiovascular disease (CVD) mortality, morbidity and stroke in individuals with AF.

METHODS AND RESULTS

We followed 1117 AF patients from the HUNT3 study in 2006-08 until first occurrence of the outcomes or end of follow-up in November 2015. We used Cox proportional hazard regression to examine the prospective associations of self-reported PA and eCRF with the outcomes. Atrial fibrillation patients meeting PA guidelines had lower risk of all-cause [hazard ratio (HR) 0.55, 95% confidence interval (CI) 0.41-0.75] and CVD mortality (HR 0.54, 95% CI 0.34-0.86) compared with inactive patients. The respective HRs for CVD morbidity and stroke were 0.78 (95% CI 0.58-1.04) and 0.70 (95% CI 0.42-1.15). Each 1-metabolic equivalent task (MET) higher eCRF was associated with a lower risk of all-cause (HR 0.88, 95% CI 0.81-0.95), CVD mortality (HR 0.85, 95% CI 0.76-0.95), and morbidity (HR 0.88, 95% CI 0.82-0.95).

CONCLUSION

Higher PA and CRF are associated with lower long-term risk of CVD and all-cause mortality in individuals with AF. The findings support a role for regular PA and improved CRF in AF patients, in order to combat the elevated risk for mortality and morbidity.

Non-genetic risk factors for atrial fibrillation are equally important in both young and old age: A nationwide population-based study

AIMS

There are several non-genetic risk factors for new-onset atrial fibrillation, including age, sex, obesity, hypertension, diabetes, and alcohol consumption. However, whether these non-genetic risk factors have equal significance among different age groups is not known. We performed a nationwide population-based analysis to compare the clinical significance of non-genetic risk factors for new-onset atrial fibrillation in various age groups.

METHODS AND RESULTS

A total of 9,797,409 people without a prior diagnosis of atrial fibrillation who underwent a national health check-up in 2009 were included. During 80,130,090 person-years of follow-up, a total of 196,136 people were diagnosed with new-onset atrial fibrillation. The impact of non-genetic risk factors on new-onset atrial fibrillation was examined in different age groups. Obesity, male sex, heavy alcohol consumption, smoking, hypertension, diabetes and chronic kidney disease were associated with an increased risk of new-onset atrial fibrillation. With minor variations, these risk factors were consistently associated with the risk of new-onset atrial fibrillation among various age groups. Using these risk factors, we created a scoring system to predict future risk of new-onset atrial fibrillation in different age groups. In receiver operating characteristic curve analysis, the predictive value of these risk factors ranged between 0.556 and 0.603, and no significant trends were observed.

CONCLUSIONS

Non-genetic risk factors for new-onset atrial fibrillation may have a similar impact on different age groups. Except for sex, these non-genetic risk factors can be modifiable. Therefore, efforts to control non-genetic risk factors might have relevance for both the young and old.

Lifestyle modifications for treatment of atrial fibrillation

The management of atrial fibrillation (AF) has focused on anticoagulation, rhythm control and ventricular rate control. Recently, a fourth pillar of AF management has been incorporated recognising the importance of risk factor management (RFM). There are several risk factors that contribute to the development and progression of AF, these include traditional risk factors such as age, hypertension, heart failure, diabetes and valvular heart disease. However, increasingly it is recognised that obesity, sleep apnoea, hyperlipidaemia, smoking, alcohol, physical inactivity, genetics, aortic stiffness are associated with the development of AF. Importantly, several of these risk factors are modifiable. We have seen the evolution of RFM programmes which have demonstrated promising results. Indeed, the evidence is now so compelling that major clinical guidelines strongly advocate that aggressive treatment of these risk factors as a key component of AF management. Patients with AF who comprehensively managed their risk factors demonstrate greater reduction in symptoms, AF burden, more successful ablations and improved outcomes with greater AF freedom. In this article, we will review the evidence for the association between cardiac risk factors and AF and assess the burgeoning evidence for improved AF outcomes associated with aggressive cardiac RFM.

Differential Modulation of IK and ICa,L Channels in High-Fat Diet-Induced Obese Guinea Pig Atria

Obesity mechanisms that make atrial tissue vulnerable to arrhythmia are poorly understood. Voltage-dependent potassium (I_K, I_Kur, and I_K1) and L-type calcium currents (I_Ca,L) are electrically relevant and represent key substrates for modulation in obesity. We investigated whether electrical remodeling produced by high-fat diet (HFD) alone or in concert with acute atrial stimulation were different. Electrophysiology was used to assess atrial electrical function after short-term HFD-feeding in guinea pigs. HFD atria displayed spontaneous beats, increased I_K (I_Kr + I_Ks) and decreased I_Ca,L densities. Only with pacing did a reduction in I_Kur and increased I_K1 phenotype emerge, leading to a further shortening of action potential duration. Computer modeling studies further indicate that the measured changes in potassium and calcium current densities contribute prominently to shortened atrial action potential duration in human heart. Our data are the first to show that multiple mechanisms (shortened action potential duration, early afterdepolarizations and increased incidence of spontaneous beats) may underlie initiation of supraventricular arrhythmias in obese guinea pig hearts. These results offer different mechanistic insights with implications for obese patients harboring supraventricular arrhythmias.

Weight and weight change and risk of atrial fibrillation: the HUNT study

Aims

Although obesity has been associated with risk of atrial fibrillation (AF), the associations of long-term obesity, recent obesity, and weight change with AF risk throughout adulthood are uncertain.

Methods and results

An ambispective cohort study was conducted which included 15 214 individuals. The cohort was created from 2006 to 2008 (the baseline) and was followed for incident AF until 2015. Weight and height were directly measured at baseline. Data on previous weight and height were retrieved retrospectively from measurements conducted 10, 20, and 40 years prior to baseline. Average body mass index (BMI) over time and weight change was calculated. During follow-up, 1149 participants developed AF. The multivariable-adjusted hazard ratios were 1.2 (95% confidence interval 1.0–1.4) for average BMI 25.0–29.9 kg/m2 and 1.6 (1.2–2.0) for average BMI ≥30 kg/m2 when compared with normal weight. The association of average BMI with AF risk was only slightly attenuated after adjustment for most recent BMI. In contrast, current BMI was not strongly associated with the risk of AF after adjustment for average BMI earlier in life. Compared with stable BMI, both loss and gain in BMI were associated with increased AF risk. After adjustment for most recent BMI, the association of BMI gain with AF risk was largely unchanged, while the association of BMI loss with AF risk was weakened.

Conclusion

Long-term obesity and BMI change are associated with AF risk. Obesity earlier in life and weight gain over time exert cumulative effects on AF development even after accounting for most recent BMI.