Effects of Dietary Inflammatory Index and History of Gestational Diabetes Mellitus on Insulin Resistance

Abstract

ObjectiveThe combined impact of previously diagnosed gestational diabetes mellitus (GDM) and dietary sources of inflammation on insulin resistance have yet to be fully examined. The objective of this study was to explore the effect modification of history of GDM on the association between the Dietary Inflammatory Index (DII)TM and beta‐cell function and insulin resistance, using homeostatic model assessment for insulin resistance (HOMA‐IR).Research Design and MethodsData from the National Health and Nutrition Examination Survey for 2007 through 2012 were used. A total of 2,674 women (mean age=52 y) including patients with type 2 diabetes who completed one‐day 24‐hour dietary recall with information on history of GDM and HOMA‐IR were included. The DII was calculated to examine inflammatory potential of diet. Insulin resistance was estimated using the HOMA‐IR. Multivariable logistic regressions models were examined to estimate the association between history of GDM, current DII scores and insulin resistance after adjusting for age, body mass index, race/ethnicity, education, family poverty income ratio, and marital status.ResultsA history of GDM was reported by 7% (n=176) of women. The difference in HOMA‐IR levels (mean ± standard error) between women with a history of GDM and women without a history of GDM was of borderline significance (4.3 ± 0.4 vs. 3.5 ± 0.1, P=0.06). Among the women without a history of GDM, women who were in the highest (most pro‐inflammatory) tertile of DII scores had increased risk for insulin resistance compared to the lowest (most anti‐inflammatory) tertile of the DII (adjusted odds ratios=1.56; 95% CI=1.07–2.27). However, no such association was observed among the women with a previous GDM diagnosis.ConclusionsWithin a nationally representative sample, the DII was associated with insulin resistance only in women without a history of GDM. Reducing inflammatory properties of diet may be a strategy for reducing the risk of insulin resistance and eventually type 2 diabetes mellitus among women without a history of GDM.