Association between dietary inflammatory index and gestational diabetes mellitus risk in a prospective birth cohort study

Objective: Information is limited regarding the possible relationship between diet-related inflammation and the risk of gestational diabetes mellitus (GDM). This study investigated the association between the inflammatory potential of the diet, measured by the dietary inflammatory index (DII), and GDM risk in pregnant Chinese women. Methods: This study included 2639 eligible women from the Tongji Maternal and Child Health Cohort. Dietary intake was assessed by a validated semiquantitative food frequency questionnaire and was used to calculate the DII score. The DII was then validated using C-reactive protein measurements in a subsample of 133 pregnant women. GDM diagnoses were collected from medical records based on the results of a 75 g oral glucose tolerance test at 24 to 28 wk gestation. Multivariable-adjusted logistic regression models were performed to estimate the odds ratios (ORs) for GDM risk by DII score, modeled continuously and in tertiles. Results: Of the 2639 participants, 13.1% were diagnosed with GDM. DII scores ranged from -4.45 to 3.15 and were positively associated with C-reactive protein (adjusted beta : 1.28, 95% confidence interval [CI]: 0.16, 2.40; P trend = 0.023) when comparing DII tertile 3 (most pro-inflammatory) to tertile 1 (most anti-inflammatory). A significant and positive association was observed between DII scores and GDM risk (adjusted OR: 1.43; 95% CI: 1.05, 1.95; P trend = 0.022) comparing the highest versus lowest tertiles. The stratified analysis showed that this association was stronger in pregnant women who were overweight or obese before pregnancy (adjusted OR: 2.20; 95% CI: 1.03, 4.69). Conclusions: These findings suggest that a higher DII score, corresponding to a more proinflammatory diet, is associated with a higher risk of GDM, particularly in pregnant women who were overweight or obese before pregnancy. (C) 2021 Elsevier Inc. All rights reserved.