Early-pregnancy remnant cholesterol as a modifiable risk factor for gestational diabetes mellitus.

BACKGROUND

Remnant cholesterol (RC) is a known contributor to cardiovascular disease, but its role in gestational diabetes mellitus (GDM) remains insufficiently characterized.

OBJECTIVE

To examine the association between first-trimester RC levels and GDM risk, and to quantify the mediating effects of prepregnancy body mass index (BMI) and insulin sensitivity.

METHODS

This prospective cohort study included 877 pregnant women in Southeastern China. RC was calculated from first-trimester fasting lipid profiles. GDM was diagnosed via a 75 g oral glucose tolerance test at 24 to 28 weeks. Binary logistic regression, restricted cubic splines, and serial mediation models were employed for analysis.

RESULTS

Among all participants, 160 (18.2%) developed GDM. After full adjustment for confounders, women in the highest quartile of first-trimester RC had a significantly higher risk of GDM (odds ratio = 2.850, 95% CI: 1.679-4.836) compared with those in the lowest quartile. A significant positive dose-response relationship was observed (P for overall < .001). Serial mediation analysis indicated that the association between RC and GDM was partially mediated through the sequential pathway of prepregnancy BMI → Matsuda index, accounting for 13.50% of the total effect. RC also showed modest predictive performance for GDM (area under the curve = 0.673) compared with conventional lipid parameters.

CONCLUSION

Elevated first-trimester RC is independently associated with increased GDM risk. This association is partially mediated by prepregnancy BMI and subsequent insulin resistance. Measuring RC in early pregnancy may improve the identification of women at high risk for GDM.