Abstract MP47: Maternal Trimethylamine-n-oxide Is Associated With Risk Of Gestational Diabetes Mellitus In A Low-income, Urban, Multi-ethnic Population

Abstract

Introduction: Trimethylamine-N-oxide (TMAO) is a metabolite influenced by gut microbiota composition and diet (e.g. eggs and red meat). While TMAO has been associated with type 2 diabetes in adults, it is still unclear whether TMAO is associated with risk of gestational diabetes (GDM). Results from the two case-control studies conducted on this topic in China were mixed, with one showing a U-shaped association and the other showing a linear association between TMAO and GDM. There is need to examine this association in a distinct population, in which the sources of TMAO may vary. Hypothesis: We hypothesized that higher TMAO concentration in both maternal and umbilical cord blood plasma (collected within 24-72 hours of birth) is associated with higher odds of GDM. Methods: We used data from the women in the Boston Birth Cohort (enrolled from 1998 to 2013) and fitted logistic regression models to examine the association of maternal and cord blood TMAO concentration with odds of GDM. TMAO was inversely normalized and was modeled in tertiles and as a continuous variable. GDM was diagnosed by a physician; women with pre-pregnancy diabetes were excluded from analyses. Final models were adjusted for covariates (see Table footnote). Results: Among our analytic sample (n=1405 participants), 1248 contributed maternal blood and 865 contributed cord blood. A total of 123 women developed GDM. Before and after adjustment for covariates, higher concentration of TMAO in maternal blood was associated with higher odds of GDM. After adjustment for potential confounders, the highest vs. lowest tertile of TMAO was associated with 1.75 times (95% CI 1.04, 2.96) the odds of GDM (Table). We found no association between cord blood TMAO and GDM (Table). Conclusion: In a population of predominantly low-income, urban mothers, higher maternal TMAO concentration measured in maternal blood (but not cord), was associated with higher odds of GDM. Our findings need to be replicated in prospective cohort studies that measure TMAO in early pregnancy.