The graded relationship between glucose tolerance status in pregnancy and postpartum levels of low-density lipoprotein cholesterol and apolipoprotein B in young women: implications for future cardiovascular risk

Gestational diabetes mellitus (GDM) or gestational impaired glucose tolerance (GIGT) has been shown to increase a woman's risk of developing future cardiovascular disease (CVD). With the mediators of this increased risk unidentified, Retnakaran et al. sought to characterize the relationship between the extent of gestational dysglycaemia and lipid concentrations, both during pregnancy and postpartum.

Women (n = 482) were recruited in the late second trimester and underwent an antepartum glucose challenge test (GCT) and oral glucose tolerance test (OGTT). Based upon the results, the women were then stratified into the following glucose tolerance groups: normal GCT and normal glucose tolerance (NGT) (n = 87); abnormal GCT with NGT (n = 170); GIGT (n = 89); GDM (n = 136). Fasting lipid profiles were measured during pregnancy and repeated at three months postpartum.

During pregnancy, no significant differences between the groups were noted for any of the lipid parameters, with the exception of high-density lipoprotein (HDL) cholesterol, which was lowest in the GDM group (P = 0.0226). However, at three months postpartum, a progressive increase in the following lipid parameters was observed as gestational glucose dysregulation worsened across the groups: total cholesterol (P = 0.0047), low-density lipoprotein (LDL) cholesterol (P = 0.0002), triglycerides (P = 0.0002), total cholesterol to HDL ratio (P < 0.0001), apolipoprotein B (apoB) (P = 0.0003) and apoB to apoA1 ratio (P = 0.0014). Multiple linear regression analysis revealed both GDM and GIGT to be independent positive predictors of total cholesterol to HDL cholesterol ratio, apo B, apoB to apoA1 ratio (P < 0.0500) and HDL cholesterol (P ≤ 0.0363). GDM was also an independent positive predictor of total cholesterol, LDL cholesterol and triglycerides (P ≤ 0.0021).

The results of this study conclude that women with GDM or GIGT have more atherogenic lipid profiles, which are evident as early as three months postpartum, and may contribute to the increased risk of CVD in these women.