Association of maternal dietary patterns derived by multiple approaches with gestational diabetes mellitus: a prospective cohort study

We used two a priori diet scores [Mediterranean diet (aMed) and Diet Balance Index (DBI)] and two a posteriori approaches [principal components analysis (PCA) and reduced-rank regression (RRR)] to examine the association of maternal dietary patterns with risk of gestational diabetes mellitus (GDM) and blood glucose among 2202 pregnant women in the Tongji Birth Cohort. Compared to the highest quartile of the aMed and legumes-vegetables-fruits (derived by PCA) scores, the fasting blood glucose (FBG) levels were higher in the lower quartiles (p-trend < 0.05). Lower scores of the meats-eggs-dairy (derived by PCA) and eggs-fish patterns (derived by RRR; characterised by higher intakes of freshwater fish, eggs, and lower intakes of leafy and cruciferous vegetables and fruits) were associated with decreased FBG levels (p-trend < 0.05). Similarities were found across approaches that some dietary patterns were associated with FBG, but not with postprandial glucose and GDM risk.