Association of first-trimester inflammatory markers with gestational diabetes mellitus subtypes and patterns: a...

To evaluate the associations between first-trimester inflammatory markers and gestational diabetes mellitus (GDM), including its subtypes and patterns, and to explore the role of these markers in the early identification of GDM risk.

This cohort study included pregnant women aged ≥ 18 years and < 16 weeks of gestation, based on their first antenatal registration date, at a tertiary hospital from March to December 2023 retrospectively and from December 2023 to August 2024 prospectively. Inflammatory markers, calculated from peripheral blood cell counts, included the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and aggregated immune-inflammation index (AISI). Outcomes were GDM and its subtypes (isolated fasting hyperglycemia [IFH], isolated post-load hyperglycemia [IPH], and combined hyperglycemia [CH]), as well as patterns identified through latent class trajectory modeling based on blood glucose change during the OGTT.

Among 4,426 eligible women, 821 developed GDM. Elevated first-trimester NLR, SII, SIRI, and AISI were significantly associated with higher GDM risk. Compared with non-GDM pregnant women, these markers were positively associated with both IPH (ORs range: 1.16-1.22) and CH (ORs range: 1.28-1.54), but not IFH, and with two OGTT glucose trajectories (medium-speed increase-rapid decrease group [ORs range: 1.20-1.25] and rapid increase-slow decrease group [ORs range: 1.31-1.68]), while no significant associations were observed for the other two trajectories.

First-trimester inflammatory markers are associated with more severe GDM phenotypes and may serve as potential biomarkers to inform the early identification of higher-risk GDM phenotypes.