Inflammatory Potential of the Diet and Subclinical Cardiovascular Disease in U.S. Adults from NHANES 1999-2004

Abstract

Background: Chronic inflammation plays a critical role in the development of cardiovascular disease (CVD), and diet is a major modifiable determinant of systemic inflammation. The Comprehensive Dietary Inflammatory Index (CDII) is a newly developed dietary score designed to quantify the inflammatory potential of dietary intake based on selected pro- and anti-inflammatory food groups. Although prior studies have linked inflammatory dietary patterns with chronic disease outcomes, the association between CDII and subclinical cardiovascular disease biomarkers remains unclear. This study aims to evaluate the relationship between CDII and biomarkers of subclinical myocardial injury and stress among U.S. adults. Methods: This cross-sectional study will use data from the National Health and Nutrition Examination Survey (NHANES) 1999–2004, including adults aged ≥20 years with complete dietary, biomarker, and covariate data. Dietary intake obtained from 24-hour dietary recalls will be used to calculate CDII scores based on eight food groups representing inflammatory dietary potential. Higher CDII scores indicate more pro-inflammatory diets. Subclinical cardiovascular disease will be assessed using high-sensitivity cardiac biomarkers, including cardiac troponin T (cTnT), cardiac troponin I (cTnI), and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Multivariable linear regression models will examine associations between CDII and continuous biomarker concentrations, while logistic regression models will estimate odds of elevated biomarker levels using clinically established thresholds. Analyses will account for NHANES sampling weights and adjust for demographic, lifestyle, and clinical covariates, including age, sex, race/ethnicity, smoking, alcohol use, physical activity, body mass index, hypertension, diabetes, and total energy intake. Expected Results: We hypothesize that higher CDII scores, reflecting more pro-inflammatory diets, will be associated with higher concentrations of cTnT, cTnI, and NT-proBNP, as well as greater odds of elevated biomarker levels. These findings would suggest that dietary inflammatory potential contributes to early myocardial injury and cardiac stress before the onset of clinically apparent cardiovascular disease. Conclusions: This study will provide novel evidence on the association between dietary inflammatory potential and subclinical cardiovascular disease in a nationally representative sample of U.S. adults. The findings may support dietary interventions targeting inflammation as a strategy for early cardiovascular disease prevention. Given that the CDII is a newly developed measure that has not yet undergone formal validation, results should be interpreted as exploratory and warrant confirmation in future studies.