Longitudinal Assessment of Routine Blood-Derived Inflammatory Indices in Women with Diet-Controlled Gestational...

To characterize longitudinal changes in routine blood count-derived inflammatory indices throughout pregnancy and the early postpartum period in women with diet-controlled gestational diabetes mellitus (GDM A1) compared with normoglycemic controls.

This retrospective cohort study included 366 pregnant women, comprising 170 women with GDM A1 and 196 normoglycemic controls, who received antenatal care at Beijing Friendship Hospital. Routine complete blood count parameters were collected at seven clinically relevant time windows: 8-12, 16-20, 24-28, 28-32, and 36 weeks of gestation, immediately before delivery, and postpartum. The aggregate index of systemic inflammation (AISI), systemic inflammation response index (SIRI), systemic immune-inflammation index (SII), lymphocyte-to-monocyte ratio (LMR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) were calculated. Exploratory unadjusted between-group comparisons were performed using Mann-Whitney U-tests. Adjusted linear mixed-effects models were used to evaluate group-by-time interactions while accounting for within-subject correlation and baseline covariates.

Women with GDM A1 were older and had higher early-pregnancy BMI than normoglycemic controls. After adjustment for maternal age, early-pregnancy BMI, gravidity, parity, and history of macrosomia, significant group-by-time interactions were observed for all six inflammatory indices, including AISI (P < 0.001), SIRI (P < 0.001), SII (P = 0.017), LMR (P = 0.011), MLR (P = 0.011), and PLR (P = 0.022). In Holm-adjusted post hoc comparisons, SIRI was higher in the GDM A1 group during the postpartum period (adjusted ratio = 1.204, 95% CI: 1.066-1.360, P = 0.020), and PLR was higher immediately before delivery (adjusted ratio = 1.123, 95% CI: 1.036-1.217, P = 0.032).

Women with GDM A1 showed altered longitudinal trajectories of CBC-derived inflammatory indices, with the most robust adjusted time-specific differences involving postpartum SIRI and pre-delivery PLR. These indices may provide accessible research markers for characterizing stage-specific inflammatory patterns in diet-controlled GDM, but prospective studies incorporating direct inflammatory and metabolic measurements are required to establish clinical utility.