Abstract
BACKGROUND & AIMS: This study was designed to investigate the association between the dietary inflammatory index (DII(®)) scores, metabolic phenotypes, and risk of mortality risk in overweight/obese individuals from a representative sample of the U.S. METHODS: Data from 3733 overweight/obese adults (BMI ≥ 25 kg/m(2)) aged 20-90 years from the National Health and Nutrition Examination Survey III, 1988-1994 were analyzed; these participants were followed for mortality through December 31, 2011. DII scores were computed based on baseline dietary intake using 24-h dietary recalls. Metabolically unhealthy status was defined as having 2 or more of these metabolic abnormalities: high glucose, insulin resistance, elevated blood pressure, triglycerides, C-reactive protein levels, or low high-density lipoprotein-cholesterol values. RESULTS: In metabolically unhealthy overweight/obese (MUO) individuals, DII score was associated with increased risk of all-cause mortality (HR(Tertile 3 vs Tertile 1) 1.44; 95% CI 1.11-1.86 P(trend) = 0.008; HR(1SD increase) 1.08; 95% CI 0.99-1.18). Additionally, a stronger association with cardiovascular mortality was observed (HR(T3 vs T1) 3.29; 95% CI 2.01-5.37 P(trend) < 0.001; HR(1SD increase) 1.40; 95% CI 1.18-1.66), after adjusting for potential confounders. Furthermore, when analyses were restricted to obese individuals (BMI ≥ 30 kg/m(2)), the association was more pronounced, especially for cardiovascular mortality (HR(T3 vs T1) 5.55; 95% CI 2.11-14.57 P(trend) = 0.006; HR(1SD increase) 1.74; 95% CI 1.21-2.50). No association was observed between DII score and risk of mortality in individuals with metabolically healthy overweight/obese (MHO) phenotype, or for cancer mortality in either MHO or MUO phenotype. CONCLUSIONS: A pro-inflammatory diet appears to increase risk of all-cause and cardiovascular mortality in the MUO phenotype, but not among the MHO phenotype.