Association between thoracic fat measured using computed tomography and lung function in a population without respiratory diseases

Background: Local fat distribution patterns and their local or systemic effects have recently attracted significant attention. The aim of this study was to assess the impact of thoracic adiposity on lung function in a population without respiratory diseases according to sex.

Methods: A total of 455 subjects (282 males and 173 females), who had undergone spirometry, and chest and abdominal computed tomography between June 2012 and June 2016 at medical healthcare center, were included. Pericardial fat, intrathoracic fat, subcutaneous thoracic fat, and both visceral and subcutaneous abdominal fat were measured by directly assessing tissue volume using computed tomography. Multiple linear regression analyses adjusted for pack-years of smoking, high-density lipoprotein, and high-sensitivity C-reactive protein were performed to evaluate the association between fat volumes and lung function.

Results: In males, intrathoracic fat and visceral abdominal fat were inversely associated with forced expiratory volume in 1 s (FEV₁) % predicted (P=0.025, P=0.010, respectively), and subcutaneous thoracic fat volumes showed a negative correlation with both FEV₁% and forced vital capacity (FVC) % predicted (P=0.019, P=0.045, respectively). In females, subcutaneous thoracic fat demonstrated a negative correlation with both FEV₁% and FVC % predicted (P=0.031 and P=0.008, respectively).

Conclusions: The influence of local thoracic fat distribution on lung function differed according to sex. Visceral fat and subcutaneous thoracic fat in males and subcutaneous fat in females were significantly associated with decreased lung function.