Maternal overweight and obesity modify the association of serum fibroblast growth factor 21 levels with gestational diabetes mellitus: A nested case-control study

Aims: To examine the prospective association between fibroblast growth factor 21 (FGF21) and risk of gestational diabetes mellitus (GDM) and the modifying effect of overweight/obesity for this association. Methods: Serum FGF21 levels were measured at 6-15 weeks of gestation among 332 GDM cases and 664 matched controls. Conditional logistic regression was used to evaluate its association with GDM risk. Interaction analyses on multiplicative and additive scales were conducted to investigate the modifying effect of overweight/ obesity. Results: Elevated FGF21 levels were associated with a higher risk of GDM in multivariable models, but the positive association was attenuated after further adjustment for pre-pregnancy body mass index (BMI). A significant multiplicative interaction was noted between FGF21 (both continuous and dichotomous) and prepregnancy BMI (p for interaction = 0.049 and 0.03), and the association was only significant in participants with pre-pregnancy BMI =24 kg/m(2). When participants were grouped based on pre- pregnancy BMI (=24 and <24 kg/m(2)) and FGF21 levels (=median and

Automated summary

This study found that elevated serum FGF21 levels during pregnancy are associated with an increased risk of GDM, but this positive association is attenuated after adjusting for pre-pregnancy BMI. Additionally, the study found a modifying effect of overweight/obesity on the association between FGF21 and GDM risk, with the association being significant only in participants with a pre-pregnancy BMI of 24 kg/m(2).