# Association between cardiac arrhythmia before pregnancy and gestational diabetes: a nationwide population-based study in Korea

## TL;DR

Women with heart rhythm issues before pregnancy are more likely to develop gestational diabetes, even after adjusting for other risk factors.

## Contribution

This study identifies a novel association between pre-pregnancy cardiac arrhythmias and increased risk of gestational diabetes in a large Korean population.

## Key findings

- Cardiac arrhythmias were present in 0.9% of the studied pregnancies.
- Gestational diabetes occurred in 8.7% of pregnancies, with a significantly higher rate in women with arrhythmias (14.9%).
- The adjusted odds ratio for GDM in women with arrhythmias was 1.78, remaining significant after controlling for age, BMI, and hypertension.

## Abstract

Given the higher prevalence of cardiac arrhythmias in individuals with diabetes, we investigated the relationship between cardiac arrhythmias and the incidence of gestational diabetes (GDM). This retrospective cohort study utilized data from the Korean Health Insurance Service database, encompassing 1,113,729 women who gave birth between January 2007 and December 2015. After excluding those who did not undergo National Health Screening tests within 1 year prior to pregnancy, those with multifetal pregnancies, and those diagnosed with diabetes, we analyzed 365,880 singleton pregnancies without a history of diabetes. Of these, 3,253 (0.9%) had cardiac arrhythmias, including premature extra beats, supraventricular tachyarrhythmias, and/or atrial flutter/fibrillation. GDM occurred in 31,938 (8.7%) subjects during pregnancy, and was more prevalent in women with cardiac arrhythmia than in those without (14.9 vs. 8.7%, p<0.001). In the multivariate analysis, the association between cardiac arrhythmia and GDM remained statistically significant (adjusted odds ratio, 1.78; 95% confidence interval, 1.61 to 1.97; p<0.001). Subgroup analysis revealed that the risk of GDM was consistently statistically significant in subjects with cardiac arrhythmia, regardless of age, body mass index, and the presence or absence of chronic hypertension. Therefore, cardiac arrhythmias before and during pregnancy appear to be associated with an increased risk of developing GDM.