BACKGROUND

Recent findings suggest remnant cholesterol (RC) may contribute to gestational diabetes mellitus (GDM). This study aimed to explore the link between RC and GDM in early pregnancy to assess RC's risk independently of triglycerides (TG).

METHODS

We performed a retrospective cohort study involving pregnant women admitted to the Suzhou Ninth Hospital affiliated to Soochow University. Data were obtained from the electronic medical record system. RC (mg/dL) was determined by subtracting high-density lipoprotein cholesterol and low-density lipoprotein cholesterol from total cholesterol. GDM was diagnosed using a 75-g oral glucose tolerance test diagnosed at 24-28 weeks of pregnancy. Various analyses, including logistic regressions, restricted cubic spline (RCS), subgroup, sensitivity, and receiver operating characteristic (ROC) analyses, were performed to evaluate the independent association between RC levels and GDM. We conducted discordance analyses to assess GDM risk in RC versus TG discordant and concordant groups using various cut points. The link between RC and different GDM subtypes was also further examined.

RESULTS

Of the 1,361 women studied, 353 (25.9%) developed GDM. After adjusting for multiple variables, RC was linked to a higher risk of GDM, with an odds ratio (OR) of 1.05 and a 95% confidence interval (CI) of 1.02-1.08. Individuals in the highest RC quartile were more likely to develop GDM (OR: 2.27, 95% CI: 1.37-3.74) than those in the lower quartile. Additionally, the adjusted RCS analysis revealed a significant linear-dose-response link between RC and GDM risk (P for all < 0.001; P for nonlinear = 0.357). Various sensitivity and subgroup analyses confirmed the robustness of our results. The discordant low TG and high RC group revealed an association with GDM, whereas the high TG and low RC group did not when compared with the low TG and low RC group. Even after adjusting for variables, the association remained significant. Similar results were observed using varying clinical cut points. In early pregnancy, RC emerged as the strongest diagnostic marker for GDM, with an ROC curve area of 0.687, surpassing other traditional lipid markers. Further analysis revealed a strong connection between early pregnancy RC levels and GDM subtypes marked solely by high fasting glucose.

CONCLUSIONS

Higher RC levels were linked to GDM independently of traditional risk factors, especially TG levels, and may be more useful in diagnosing specific GDM subtypes.