The effects of truncal adiposity in forced spirometry: Sex differences

The aim of the current paper is to establish the influence of truncal fat accumulation on the spirometric results of a group of healthy individuals. A cross-sectional study of 305 healthy, non-smoking adult subjects (144 males, 161 females) was conducted. Forced spirometry and dual-energy X-ray absorptiometry to quantify body fat were performed. Partial correlation and multiple linear regression analyses were performed. In females, abdominal fat was negatively correlated with forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁). In males, thoracic fat was negatively correlated with respiratory variables, as was abdominal fat. In the multiple linear regression, FEV₁ was the spirometric parameter that showed higher R² values in both sexes. Truncal fat had a greater influence on FEV₁ than on FVC. In males, no significant differences between the influence of thoracic and abdominal fat on spirometric results were found, and total body fat was shown to have more influence than regional. In females, the influence of abdominal fat was higher.