Association of dietary inflammatory index with risk of gestational diabetes mellitus and preeclampsia: a systematic review and meta-analysis

Findings from observational studies have suggested a possible association between dietary inflammatory index (DII) and risk of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the results of these studies were inconclusive. A systematic review and meta-analysis was carried out to illuminate this association. Systematic literature search was conducted in PubMed, Web of Science, Cochrane Library, EMBASE, Scopus and other databases from inception until January 2023. The qualities of included studies were assessed using the Newcastle-Ottawa scale. Nine studies (seven cohort, two case-control) were included in the meta-analysis, including 11 423 participants from five different countries. The meta-analysis indicated that a 1-unit increase in the DII score, representing pro-inflammatory diet, was associated with 13 % higher risk of GDM (OR = 1 & BULL;13; 95 % CI 1 & BULL;02, 1 & BULL;25, I2 = 68 & BULL;4 %, P = 0 & BULL;004) and 24 % higher risk of PE (OR = 1 & BULL;24; 95 % CI 1 & BULL;14, 1 & BULL;35, I2 = 52 & BULL;0 %, P = 0 & BULL;125). Subgroup analysis found that this association was evident among studies with Chinese populations (OR = 1 & BULL;16; 95 % CI 1 & BULL;06, 1 & BULL;28) and studies with mid pregnancy (OR = 1 & BULL;20; 95 % CI 1 & BULL;07, 1 & BULL;34). The findings indicate that pro-inflammatory diet can increase the risk of GDM and PE. Considering some limitations in this study, more studies are needed to verify this association.