SEOUL, South Korea – Menopause before age 40 is associated with elevated risk of heart failure and atrial fibrillation, according to a study published in European Heart Journal, from the European Society of Cardiology (ESC). The study of more than 1.4 million women revealed that the younger the age at menopause, the higher the risk of heart failure and atrial fibrillation.
“Women with premature menopause should be aware that they may be more likely to develop heart failure or atrial fibrillation than their peers,” said study author Ga Eun Nam, MD, PhD, of Korea University College of Medicine, Seoul. “This may be good motivation to improve lifestyle habits known to be linked with heart disease, such as quitting smoking and exercising.”
Cardiovascular disease typically occurs up to 10 years later in women than men. Premenopausal women are thought to benefit from estrogen’s protective effect on the cardiovascular system. The cessation of menstruation and subsequent decline of estrogen levels may make women more vulnerable to cardiovascular disease.
A national population
Premature menopause affects 1% of women younger than 40 years, the ESC press release stated. Prior studies have found a link between premature (before age 40 years) and early (before age 45 years) menopause and cardiovascular disease overall, but the evidence for heart failure or atrial fibrillation alone is limited. This study examined the associations between premature menopause, age at menopause, and incident heart failure and atrial fibrillation. Data were obtained from the Korean National Health Insurance System (NHIS), which provides health screening at least every 2 years and includes 97% of the population.
The study included 1,401,175 postmenopausal women aged 30 years and older who completed the NHIS health checkup in 2009. Participants were monitored until the end of 2018 for new-onset heart failure and atrial fibrillation. Information was collected on demographics, health behaviors, and reproductive factors, including age at menopause and use of hormone replacement therapy (HRT). Age at menopause was split into four categories: younger than 40 years, 40-44 years, 45-49 years, and 50 years or older. Premature menopause was defined as having the final menstrual period before age 40 years.
Some 28,111 (2%) participants had a history of premature menopause. For these women, the average age at menopause was 36.7 years. The average age at study enrollment for women with and for those without a history of premature menopause was 60 and 61.5 years, respectively. During an average follow-up of 9.1 years, 42,699 (3.0%) developed heart failure, and 44,834 (3.2%) developed atrial fibrillation.
The researchers analyzed the association between history of premature menopause and incident heart failure and atrial fibrillation after adjusting for age, smoking, alcohol use, physical activity, income, body mass index, hypertension, type 2 diabetes, dyslipidemia, chronic kidney disease, coronary heart disease, HRT, and age at menarche. Women who experienced premature menopause had a 33% higher risk for heart failure and 9% higher risk for atrial fibrillation, compared with those who did not.
Reproductive history
The researchers then analyzed the associations between age at menopause and incidence of heart failure and atrial fibrillation after adjusting for the same factors as in the previous analyses. The risk for incident heart failure increased as the age at menopause decreased. Compared with women aged 50 years and older at menopause, those aged 45-49 years, 40-44 years, and younger than 40 years at menopause had 11%, 23%, and 39% greater risk for incident heart failure, respectively. Similarly, the risk for incident atrial fibrillation increased as the age at menopause decreased; the risk was 4%, 10%, and 11% higher for those aged 45-49 years, 40-44 years, and younger than 40 years at menopause, respectively, compared with women aged 50 years and older at menopause.
The authors said that several factors may explain the associations between menopausal age, heart failure, and atrial fibrillation, such as the drop in estrogen levels and changes in body fat distribution.
Dr. Nam concluded, “The misconception that heart disease primarily affects men has meant that sex-specific risk factors have been largely ignored. Evidence is growing that undergoing menopause before the age of 40 years may increase the likelihood of heart disease later in life. Our study indicates that reproductive history should be routinely considered in addition to traditional risk factors such as smoking when evaluating the future likelihood of heart failure and atrial fibrillation.”
A version of this article appeared on Medscape.com. This article was translated from the Medscape French edition.