The Dietary Inflammatory Index and Current Wheeze Among Children and Adults in the United States

BACKGROUND: A proinflammatory diet may increase allergic airway inflammation by affecting innate and adaptive immune responses. OBJECTIVE: In this study, we examine the relation between the diet's inflammatory potential, measured by the Dietary Inflammatory Index (DII), and current asthma, current wheeze, and lung function in U.S. children and adults. METHODS: We analyzed data from 8,175 children (aged 6-17 years) and 22,294 adults (aged 18-79 years) who participated in the 2007-2012 National Health and Nutrition Examination Survey. The DII was calculated by nutrient intake based on 24 hour dietary recalls, and normalized as per 1,000 calories of food consumed to account for total energy intake. Multivariable regression models were used for the analysis of the DII and current asthma, current wheeze, and lung function measures. RESULTS: Higher DII (a proinflammatory diet) was associated with current wheeze among adults (eg, odds ratio [OR] for quartile 4 vs 1, OR = 1.41, 95% confidence interval [CI] = 1.17-1.70; Arm,p(trend) <.01) and among children with high fractional exhaled nitric oxide (a marker of eosinophilic airway inflammation; OR = 2.38, 95% CI = 1.13-5.02; P-trend =.05). The DII also was associated with decreased forced expiratory volume in 1 second and forced vital capacity in adults without asthma or wheezing. The DII was not associated with lung function in children or current asthma in either age group. CONCLUSIONS: Our findings suggest that a proinflammatory diet, assessed by the DII, increases the odds of current wheeze in adults and children with allergic (atopic) wheeze. These results further support testing dietary interventions as part of the management of asthma. (C) 2018 American Academy of Allergy, Asthma & Immunology