The risk of atrial fibrillation (AF) is increased by all adverse pregnancy outcomes except small for gestational age, according to a recent study published in JAMA Cardiology.1
AF has been indicated as a growing public health burden, impacting more than 50 million patients worldwide. Reproductive-aged women are especially experiencing a growing prevalence. Additionally, adverse pregnancy outcomes have been reported as factors influencing future cardiovascular health.
Key takeaways:
- A Swedish national cohort study found that 5 of 6 major adverse pregnancy outcomes were linked to a higher risk of atrial fibrillation (AF) later in life.
- The strongest associations with AF were observed for other hypertensive disorders of pregnancy, preeclampsia, and preterm delivery.
- Risks for AF often persisted for decades, with some appearing up to 20 years after delivery.
- Small for gestational age was the only adverse pregnancy outcome not associated with increased AF risk.
- Experts emphasize the need for early cardiovascular prevention and long-term follow-up for women with adverse pregnancy outcomes.
“Most studies have had insufficient follow-up times (<15 years) to assess risk at older ages when AF is more common,” wrote investigators.
Assessing AF risk
The national cohort study was conducted to address these knowledge gaps and assess AF risk in patients with major adverse pregnancy outcomes. Data about women with singleton delivery from 1973 to 2015 was obtained from the Swedish Medical Birth Register. Women with a prior AF diagnosis were excluded from the analysis.
Preterm delivery, small for gestational age (SGA), large for gestational age (LGA), preeclampsia, other hypertensive disorders of pregnancy, and gestational diabetes were reported as major adverse pregnancy outcomes. SGA was defined as birth weight under the 10th percentile for gestational age, and LGA as above the 90th percentile.
Follow-up lasted through December 31, 2018, with a maximum duration of 46 years and a median duration of 25 years. International Classification of Diseases codes were used to diagnose AF. Covariates included maternal age, parity, calendar year of delivery, employment status, income, and education level.
AF risk by pregnancy outcome
There were 2,201,047 women included in the final analysis, 39.3% of whom experienced at least 1 major adverse pregnancy outcome. LGA, SGA, and preterm delivery were the most common outcomes, reported in 14.8%, 14.3%, and 8.9%, respectively. AF was reported in 2.3% of participants across 54 million person-years of follow-up.
Participants were aged a median of 27 years at first delivery, 63 years at AF diagnosis, and 53 years at the end of follow-up. An association was reported with AF for all major adverse pregnancy outcomes except SGA.
Other hypertensive disorders of pregnancy had the greatest link to AF, with a hazard ratio of 1.46. This was followed by:
