Adiposity, Adipokines, and Exhaled Nitric Oxide in Healthy Adults Without Asthma

Abstract

Background. Epidemiological studies have shown that obesity//adiposity is closely associated with asthma in terms of development, severity, and control of asthma. However, effects of obesity//adiposity on airway inflammation are not well known in subjects without asthma. We assessed whether fractional exhaled nitric oxide (FeNO), a marker of eosinophilic airway inflammation, was associated with obesity//adiposity in nonasthmatic healthy adults. Methods. We measured FeNO and serum levels of adipose-derived hormones and adipokines in 117 adult subjects without a previous diagnosis of asthma or current asthmatic symptoms. Associations between FeNO and measures of obesity//adiposity [body mass index (BMI), body fat mass, and body fat percentages] were examined by correlation analyses and uni- and multivariate linear regression analyses. Results. FeNO was not significantly associated with BMI, body fat mass, or body fat percentage by a multivariate linear regression model, adjusting for age, gender, chronic rhinitis, atopy, and lung function. No significant association of FeNO with serum levels of leptin, adiponectin, tumor necrosis factor (TNF)-alpha alpha, or interleukin (IL)-6 was observed. Conclusions. These findings suggest that in healthy subjects without asthma, obesity//adiposity has no significant effect on eosinophilic airway inflammation and that hormones and systemic inflammation derived from adipose tissue do not affect eosinophilic airway inflammation.