Pulmonary function and abdominal adiposity in the general population

Background: The prevalence of obesity is increasing, and there is evidence that obesity, in particular abdominal obesity as a marker of insulin resistance, is negatively associated with pulmonary function. The mechanism for this association and the best marker of abdominal adiposity in relation to pulmonary function is not known. Study objective: We assessed the association between pulmonary function and weight, body mass index (BMI), waist circumference, waist/hip ratio, and abdominal height as markers of adiposity and body fat distribution. We used multiple linear regression to analyze the association of pulmonary function (ie, FEV₁ and FVC) [with maneuvers performed in the sitting position] with overall adiposity markers (ie, weight and BMI) and abdominal adiposity markers, stratified by gender, and adjusted for height, age, race, smoking, and other covariates. Setting and participants: A random sample of individuals (n = 2,153) from the general population living in western New York state, 35 to 79 years of age. Results: In women, abdominal height and waist circumference were negatively associated with FEV₁ percent predicted, while all five adiposity markers were negatively associated with FVC percent predicted. In men, all overall and abdominal adiposity markers were inversely associated with FEV₁ percent predicted and FVC percent predicted. Conclusion: These results suggest that abdominal adiposity is a better predictor of pulmonary function than weight or BMI, and investigators should consider it when investigating the determinants of pulmonary function.