6707 Preconception Lipids, Birthweight, And Pregnancy Outcomes In Pre-existing Diabetes
Authors: Chang Joycie , Hsu Sarah , Thaweethai Tanayott , James Kaitlyn E , Shook Lydia L , Maya Jacqueline , Powe Camille Elise 
Published: October 2024

Abstract
Disclosure: J. Chang: None. S. Hsu: None. T. Thaweethai: None. K.E. James: None. L.L. Shook: None. J. Maya: None. C.E. Powe: Consulting Fee; Self; Mediflix Inc. Other; Self; Wolters Kluwer, Up to Date Author.
Objective Prior studies suggest that higher preconception triglycerides are associated with higher infant birthweight in people without pre-existing diabetes. People with pre-existing diabetes have high risk for dyslipidemia and large for gestational age (LGA) neonates; however, data is scarce on the association between preconception lipids and pregnancy outcomes in this population. Methods: We retrospectively analyzed pregnancies with pre-existing diabetes who had triglyceride levels available prior to conception. We used generalized estimating equations (GEE) for linear regression to examine the association of preconception log-transformed triglycerides with birthweight percentile (primary outcome) while accounting for pregnancies that occurred in the same person. We used logistic regression via GEE for other pregnancy outcomes, including LGA. We built unadjusted models and models adjusted for maternal age, race/ethnicity, parity, insurance status, marital status, first trimester blood pressure, and BMI and hemoglobin A1C at 12 weeks’ gestation. We assessed for effect modification by diabetes type via stratification and interaction models. Results: Among 217 pregnancies in 189 people, 27% had preconception triglycerides ≥150 mg/dL and 32% resulted in LGA infants. Log-transformed triglycerides were not significantly associated with birthweight percentile in the full cohort in either adjusted (P = 0.62) or unadjusted models (P = 0.35). However, in unadjusted analyses stratified by diabetes type, a one unit increase in log-transformed triglycerides was associated with a 10.4 percentile increase in birthweight in pregnancies with type 2 diabetes (T2D; N=137) (95% confidence interval [CI] [1.12, 19.63], P = 0.03) and a 16.0 percentile decrease in birthweight in those with type 1 diabetes (T1D; N=76) (95% CI [-30.03, -1.95], P = 0.03). These associations were significantly different from each other (P for interaction = 0.002). Associations were attenuated after multivariate adjustment (T2D: β = 6.62, 95% CI [-3.42, 16.66], P= 0.20; T1D: β = -11.12, 95% CI [-23.61, 1.37], P= 0.08). Analyses of LGA incidence were consistent with primary findings, as those with T2D and higher log-transformed triglyceride levels were more likely to have LGA infants (odds ratio [OR] = 3.84, 95% CI [1.71, 8.62], P= 0.001) while an inverse association was seen in T1D (OR = 0.35, 95% CI [0.13, 0.94], P= 0.04). After multivariate adjustment, the association with LGA persisted in T2D (OR = 4.03, 95% CI [1.42, 11.44], P= 0.01) but was attenuated in T1D (OR = 0.34, 95% CI [0.09, 1.27], P= 0.11). Conclusion: Higher preconception triglycerides are associated with higher infant birthweight in people with T2D, while the inverse may be seen in those with T1D. Mechanisms linking preconception triglycerides and birthweight in people with diabetes should be examined in future studies.
Presentation: 6/2/2024