Maternal Lipid Profile Differs by Gestational Diabetes Physiologic Subtype

Aim: To characterize lipid profiles in women with different gestational diabetes mellitus (GDM) physiologic subtypes.

Methods: We measured seven lipid markers (total cholesterol, LDL, HDL, triglycerides, non-esterified fatty acids (NEFA), ApoA, ApoB) in fasting plasma collected in a prospective cohort of 805 pregnant women during second trimester. We estimated insulin sensitivity and secretion using oral glucose tolerance test-based validated indices. We categorized GDM physiologic subtypes by insulin sensitivity and secretion defects defined as values below the 25th percentile among women with normal glucose tolerance (NGT), as previously established. We compared lipid markers across NGT and GDM subtypes. We explored associations between lipid markers and newborn anthropometry in the overall group and stratified by glucose tolerance status.

Results: Among 805 women, 67 (8.3%) developed GDM. Women with GDM had higher body mass index (BMI; 29.3 vs. 26.6 kg/m), while ethnicity (97.3% vs. 97.0% European ancestry) and age (28 vs. 29 years) were similar. In comparison to women with NGT, women with GDM characterized by a predominant insulin sensitivity defect had significantly higher triglycerides (2.20 vs. 1.82, P = 0.002), lower HDL (1.64 vs. 1.90, P = 0.01) and higher NEFA (0.34 vs. 0.24, P < 0.0001). GDM women with a predominant insulin secretion defect differed from women with NGT with respect to NEFA (0.32 vs. 0.24, P = 0.003) while other lipid markers were similar. These associations remained significant after adjusting for maternal age and BMI. Greater maternal levels of NEFA were associated with higher birth weight z-scores in women with an insulin secretion defect (BMI-adjusted r = 0.58, P = 0.01). We did not find significant associations between other lipid markers and newborn anthropometry in other groups.

Conclusion: Women with GDM have distinct lipid profiles based on their GDM physiologic subtype which may not be apparent when investigating GDM as a single group.