Dietary Inflammatory Index, Pre-Frailty and Frailty Among Older US Adults: Evidence from the National Health and Nutrition Examination Survey, 2007–2014

This study aimed to investigate the association between dietary inflammation, pre-frailty and frailty among older US adults. Additionally, effect modification of gender on the association between dietary inflammation and frailty was assessed. Study data came from the National Health and Nutrition Examination Survey (2007-2014)–a nationally representative, cross-sectional study of adults. The analytic sample included adults ≥60 years (n=7,182). Dietary Inflammatory Index (DII®) scores were calculated from 24-hour dietary recalls; DII was categorized into quintiles from Quintile 1 (Q1) (least inflammatory) to Q5 (most inflammatory). Frailty was assessed by four criteria: exhaustion, weakness, low body mass, and low physical activity. Individuals were then categorized into robust (0 criteria), pre-frail (1-2 criteria), or frail (3-4 criteria). Multinomial logistic regression was used to examine the odds of frailty categories (prefrail vs. robust; frail vs. robust). After adjusting for potential confounders, individuals in DII quintile 5 (vs Q1) were more likely to be pre-frail (OR = 1.71; 95% CI: 1.36-2.15) and frail (OR = 1.70; 95% CI: 1.02- 2.85). Individuals in Q4 had greater odds of frailty only (OR = 1.82; 95% CI: 1.13, 2.93). No evidence of effect modification by gender on the association of DII and frailty was found. This study expands upon previous evidence of a relationship between dietary inflammation and frailty. When designing nutrition-based frailty interventions, inflammatory properties of diets should be considered.