Effect of upper body fat distribution on pulmonary functions in medical students

Abstract

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 objectives: We assessed the association between pulmonary function and body mass index (BMI), waist/hip ratio and Body fat percentage as markers of adiposity and body fat distribution. We used Pearson correlation coefficient to analyse the association of pulmonary function (i.e., FEV1 and FVC) [with manoeuvres performed in the sitting position] with overall adiposity markers (i.e., Body fat percentage and BMI) and abdominal adiposity markers (WHR). Methods: One forty male subjects underwent physical examination, computerised pulmonary function tests (spirometry, lung volumes) and various anthropometric measurements (waist-hip ratio, BMI, skin fold thickness) out of which seventy were case and seventy were control. Results: Result showed that expiratory reserve volume and FVC were showed negative correlation with WHR in obese group (p<0.001).There was negative correlation observed between BF% and ERV (-0.49), FVC (-0.05), and MVV (-0.11). There was negative correlation observed between BMI and ERV (-0.46) and MVV (-0.17).WHR also showed negative correlation with ERV (-0.14). Conclusion: ERV and FVC were significantly decreased in subjects with WHR more than 0.93.These results suggest that abdominal adiposity is a better predictor of pulmonary function than Body fat percentage or BMI, and investigators should consider it when investigating the determinants of pulmonary function.