An Empirical Dietary Inflammatory Pattern Score Enhances Prediction of Circulating Inflammatory Biomarkers in Adults
FKT was supported by NIH grant K99CA207736. JEC and FBH were supported by NIH grants P30 DK046200 and U54 CA155426. The Health Professionals Follow-Up Study and Nurses' Health Study II cohorts are supported by NIH grants UM1 CA167552 and UM1 CA176726, respectively.
Two indexes exist to describe dietary inflammatory potential: an empirical dietary inflammatory pattern (EDIP) composed of food groups as reported on a food-frequency questionnaire (FFQ) and a literature-derived dietary inflammatory index (DII) composed mainly of nutrients.
Objective
We compared the ability of the 2 indexes to predict concentrations of inflammatory markers and hypothesized that the EDIP would be more predictive because it was derived on the basis of circulating inflammatory markers.
Methods
Both EDIP and DII scores were calculated from FFQ data reported by 5826 women in the Nurses' Health Study II and 5227 men in the Health Professionals Follow-Up Study. We used multivariable-adjusted linear regression analyses to calculate relative differences in concentrations of 4 plasma inflammatory markers—C-reactive protein (CRP; milligrams per liter), interleukin 6 (IL-6; picograms per milliliter), tumor necrosis factor α receptor 2 (TNFαR2; picograms per milliliter), and adiponectin (nanograms per milliliter)—in quintiles of the dietary indexes.
Results
Spearman correlations between the EDIP and DII scores were modest (r = 0.29 and 0.21 for women and men, respectively; all P < 0.0001). Higher scores on both dietary indexes were associated with higher concentrations of inflammatory markers, although they were associated with lower adiponectin concentrations and there was no association between the DII and adiponectin in men. For example, percentage differences in concentrations of biomarkers in quintile 5 generally were higher (lower for adiponectin) than in quintile 1 (for the EDIP and DII, respectively—women: CRP, +60% and +49%; IL-6, +23% and +21%; TNFαR2, +7% and +4%; adiponectin, −21% and −14%; men: CRP, +38% and +29%; IL-6, +14% and +24%; TNFαR2, +9% and +5%; adiponectin, −16% and −4%.)
Conclusion
Despite design differences, the EDIP and DII both assess dietary inflammatory potential in men and women, with the EDIP showing a greater ability to predict concentrations of plasma inflammatory markers.
