Inflammatory and Insulinemic Dietary Patterns and Risk of Type 2 Diabetes Among Women With a History of Gestational Diabetes Mellitus: A Prospective Study of 84,174 Person-Years of Follow-up

OBJECTIVE We examined the associations of inflammatory and insulinemic diets with type 2 diabetes (T2D) risk among women with a history of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS We followed 4,318 women with a history of GDM in the Nurses’ Health Study II for incident T2D between 1991 and 2019. Empirical dietary inflammatory pattern (EDIP) and empirical dietary index for hyperinsulinemia (EDIH) scores were calculated using prevalidated methods. Cox models were used to calculate hazard ratios (HRs) and 95% CIs for the risk of T2D. Additionally, we estimated the least squares means of cardiometabolic biomarkers according to EDIP and EDIH quintiles in a subset of participants who were free of T2D at the time of blood collection. RESULTS During 84,174 person-years of follow-up, 1,037 women developed T2D. After adjusting for major covariates, including BMI, higher EDIP and EDIH scores, which indicated greater dietary inflammatory and insulinemic potential, were associated with an increased risk of T2D. Compared with those for the lowest quintile, adjusted HRs (95% CIs) for the highest quintile were 1.32 (1.06, 1.64) for EDIP and 1.44 (1.14, 1.82) for EDIH (both Ptrend < 0.05). Higher EDIP scores were significantly associated with higher concentrations of insulin and lower levels of HDL cholesterol, and EDIH scores were significantly positively associated with insulin and C-peptide concentrations. CONCLUSIONS Among women with a history of GDM, those with greater dietary inflammatory and insulinemic potential were found to be at a higher risk of T2D and to have unfavorable cardiometabolic profiles.