Association of gestational diabetes mellitus and low-density lipoprotein (LDL) particle size

A predominance of small, dense low-density lipoproteins (LDL) is characteristic of the dyslipidemic state seen in type 2 diabetes. However, no study has investigated the association in gestational diabetes mellitus (GDM), which is pathophysiologically similar to type 2 diabetes. We hypothesized that LDL particle size is reduced in GDM cases compared with controls. Gradient gel electrophoresis was used to characterize LDL subclass phenotypes in non-fasting intrapartum plasma from 105 GDM cases and 96 controls. All participants were free of pre-existing diabetes or hypertension. The authors used logistic regression to estimate odds ratios (OR) and 95 % confidence intervals (CI) adjusted for confounders. Women with this phenotype had a significant 4.9-fold (95 % CI: 1.1-23.2) increased risk of GDM compared with those with the large, buoyant phenotype. The magnitude of this association was attenuated when plasma triglyceride and other confounders were included in the model (OR= 4.2, 95 % CI: 0.5-39.5). Mean LDL particle size in GDM cases was smaller compared with controls (270.1 vs. 272.7 angstrom, p=0.003). The OR of GDM risk was 1.8 (95 % CI: 0.9-3.3) for every 10-angstrom reduction in LDL particle size. Large prospective studies are needed to evaluate the association between smaller LDL particle size in early pregnancy with subsequent GDM risk.