Doctors have long thought men had more risk of developing atrial fibrillation (a-fib) than women, but the reverse may actually be the case.
When researchers accounted for height differences between men and women, a new study revealed that women were 50% more likely to develop a-fib, an irregular heart rhythm disorder, than men.
"This is the first study to show an actual flip in the risk of atrial fibrillation," said senior author Dr. Christine Albert, head of cardiology at the Smidt Heart Institute at Cedars-Sinai Medical Center in Los Angeles.
Albert also led the nationwide VITAL Rhythm Trial, the basis of these findings.
"In this population of 25,000 individuals without prior heart disease, after adjusting for differences in height, women were at higher risk for developing [a-fib] than their male counterparts -- upward of 50%," Albert said in a center news release.
The taller an individual is, the greater their a-fib risk. Women tend to be shorter than men, so past research has shown their risk is lower.
“Our study, however, surprisingly suggests that if a man and a woman have the same height, the woman would be more likely to develop a-fib," Albert said. "Now the question has changed: Instead of why are women protected, now we must seek to understand why women are at a higher risk."
The findings suggest health care providers need to promote a-fib prevention and early intervention in both sexes.
"Atrial fibrillation is a disease we want to prevent, regardless of sex or gender," Albert said. "This informative study is an important step for the medical community to take note of, and begin discussing a-fib risk with all patients, whether male or female."
A-fib's effect on heart rhythm can lead to stroke or heart failure. Women who are diagnosed with a-fib are more likely to experience these consequences than men.
Experts estimate that more than 12.1 million Americans will have the condition by 2030. As the general population increases in both height and weight, heart specialists expect more will be diagnosed with a-fib.
Effective prevention strategies include maintaining a healthy weight, controlling blood pressure, limiting alcohol use and exercising moderately.
"These lifestyle modifications are important to those at risk for atrial fibrillation, but also important modifications all women can consider to prevent other heart-related conditions," said Dr. Noel Bairey Merz, director of the Barbra Streisand Women's Heart Center in the Smidt Heart Institute.
Bairey Merz, a pioneer in women's heart disease who was not involved with the study, said the data underscore the importance of prevention for women.
Albert agreed. "With incidence on the rise, it's more imperative than ever to be offering preventive strategies and early diagnostic interventions to all patients,” she said.
The findings were published Aug. 31 in JAMA Cardiology.
The American Heart Association has more on atrial fibrillation.
SOURCE: Cedars-Sinai Medical Center, news release, Aug. 31, 2022