Prospective associations of dietary inflammatory index and serum high-sensitivity C-reactive protein in the second trimester of pregnancy with the risk of gestational diabetes mellitus

Objective To assess the effectiveness of dietary inflammatory index (DⅡ) in pregnant women and the association between DⅡ and serum high-sensitivity C-reactive protein (hs-CRP) in the second trimester of pregnancy and the risk of gestational diabetes mellitus (GDM). Methods A prospective cohort study was conducted at the First Affiliated Hospital of Anhui Medical University for pregnant women. A total of 336 women with singleton pregnancy and without obvious symptoms of infection in 16-20 gestational weeks were enrolled in the study. DⅡ and serum hs-CRP concentration were measured in 16-20 gestational weeks. DⅡ was derived from individual dietary intake obtained by 3 consecutive 24-hour recalls using a validated algorithm. The participants were followed up until delivery and the pregnancy outcomes were recorded. Results A total of 110 observations (32.74% of the total 336 observations) had elevated hs-CRP (>3 mg/L). The risk of developing GDM among women in the elevated hs-CRP compared with the normal hs-CRP was 1.96(95% CI:1.03-3.75). The significant positive relationship was showed between DⅡ and hs-CRP during the second trimester of pregnancy (r=0.20,P=0.003). Three groups were divided according to tertiles of DⅡ. The lowest (most anti-inflammtory) tertile was the referent. The risk of developing GDM increased across the tertiles (i.e., with increasing inflammatory potential):odds ratio (tertile2)=3.66 (95% CI:1.11-12.12); odds ratio (tertile3)=5.99 (95% CI:1.85-19.41). Conclusions The DⅡ is a novel tool that characterizes the inflammatory potential of diet for pregnant women. A higher DⅡ is prospectively associated with a higher risk of GDM, with association with serum hs-CRP. Promotion of a healthy diet exhibiting anti-inflammatory properties may contribute to prevent GDM.