Heart Failure, Not Stroke, Most Common Complication of A-Fib

 The lifetime risk of atrial fibrillation (AF) increased from 2000 to 2022 from one in four to one in three, a Danish population-based study of temporal trends found.

Heart failure was the most frequent complication linked to this arrhythmia, with a lifetime risk of two in five, twice that of stroke, according to investigators led by Nicklas Vinter, MD, PhD, a postdoctoral researcher at the Danish Center for Health Service Research in the Department of Clinical Medicine at Aalborg University, Denmark.

Published in BMJ, the study found the lifetime risks of post-AF stroke, ischemic stroke, and myocardial infarction improved only modestly over time and remained high, with virtually no improvement in the lifetime risk of heart failure.

"Our work provides novel lifetime risk estimates that are instrumental in facilitating effective risk communication between patients and their physicians," Dr. Vinter said in an interview. "The knowledge of risks from a lifelong perspective may serve as a motivator for patients to commence or intensify preventive efforts." AF patients could, for example, adopt healthier lifestyles or adhere to prescribed medications, Dr. Vinter explained.

"The substantial lifetime risk of heart failure following atrial fibrillation necessitates heightened attention to its prevention and early detection," Dr. Vinter said. "Furthermore, the high lifetime risk of stroke remains a critical complication, which highlights the importance of continuous attention to the initiation and maintenance of oral anticoagulation therapy."

The Study

The cohort consisted of 3.5 million individuals (51.7% women) who did not have AF as of age 45 or older. These individuals were followed until incident AF, migration, death, or end of follow-up, whichever came first.

All 362,721 individuals with incident AF (53.6% men) but no prevalent complication were further followed over two time periods (2000-2010 and 2011-2020) until incident heart failure, stroke, or myocardial infarction.

Among the findings:

• Lifetime AF risk increased from 24.2% in 2000-2010 to 30.9% in 2011-2022, for a difference of 6.7% (95% confidence interval [CI], 6.5%-6.8%). 
• Lifetime AF risk rose across all subgroups over time, with a larger increase in men and individuals with heart failure, myocardial infarction, stroke, diabetes, and chronic kidney disease. 
• Lifetime risk of heart failure was 42.9% in 2000-2010 and 42.1% in 2011-2022, for a difference of −0.8% (95% CI, −3.8% to 2.2%). 
• The lifetime risks of post-AF stroke and of myocardial infarction decreased slightly between the two periods, from 22.4% to 19.9% for stroke (difference −2.5%, 95% CI, −4.2% to −0.7%) and from 13.7% to 9.8% for myocardial infarction (−3.9%, 95% CI, −5.3% to −2.4%). No differential decrease between men and women emerged. 

"Our novel quantification of the long-term downstream consequences of atrial fibrillation highlights the critical need for treatments to further decrease stroke risk as well as for heart failure prevention strategies among patients with atrial fibrillation," the Danish researchers wrote.

Offering an outsider’s perspective, John P. Higgins, MD, MBA, MPhil, a sports cardiologist at McGovern Medical School at The University of Texas Health Science Center at Houston, said, "Think of atrial fibrillation as a barometer of underlying stress on the heart. When blood pressure is high, or a patient has underlying asymptomatic coronary artery disease or heart failure, they are more likely to have episodes of atrial fibrillation."

According to Dr. Higgins, risk factors for AF are underappreciated in the United States and elsewhere, and primary care doctors need to be aware of them. "We should try to identify these risk factors and do primary prevention to improve risk factors to reduce the progression to heart failure and myocardial infarction and stroke. But lifelong prevention is even better, he added. "Doing things to prevent actually getting risk factors in the first place. So a healthy lifestyle including exercise, diet, hydration, sleep, relaxation, social contact, and a little sunlight might be the long-term keys and starting them at a young age, too."

In an accompanying editorial, Jianhua Wu, PhD, a professor of biostatistics and health data science with the Wolfson Institute of Population Health at Queen Mary University of London, and a colleague, cited the study’s robust observational research and called the analysis noteworthy for its quantification of the long-term risks of post-AF sequelae. They cautioned, however, that its grouping into two 10-year periods (2000-2010 and 2011-2020) came at the cost of losing temporal resolution. They also called out the lack of reporting on the ethnic composition of the study population, a factor that influences lifetime AF risk, and the absence of subgroup analysis by socioeconomic status, which affects incidence and outcomes.

The editorialists noted that while interventions to prevent stroke dominated AF research and guidelines during the study time period, no evidence suggests these interventions can prevent incident heart failure. "Alignment of both randomised clinical trials and guidelines to better reflect the needs of the real-world population with atrial fibrillation is necessary because further improvements to patient prognosis are likely to require a broader perspective on atrial fibrillation management beyond prevention of stroke," they wrote.

In the meantime this study "challenges research priorities and guideline design, and raises critical questions for the research and clinical communities about how the growing burden of atrial fibrillation can be stopped," they wrote.

This work was supported by the Danish Cardiovascular Academy, which is funded by the Novo Nordisk Foundation, and The Danish Heart Foundation. Dr. Vinter has been an advisory board member and consultant for AstraZeneca and has an institutional research grant from BMS/Pfizer unrelated to the current study. He reported personal consulting fees from BMS and Pfizer. Other coauthors disclosed research support from and/or consulting work for private industry, as well as grants from not-for-profit research-funding organizations. Dr. Higgins had no competing interest to declare. The editorial writers had no relevant financial interests to declare. Dr. Wu is supported by Barts Charity. 

https://www.medscape.com/s/viewarticle/heart-failure-not-stroke-most-common-complication-fib-2024a10007nz