Waist circumference is an important predictor of pulmonary function and lung age in young adult smokers
Background and Aim: Despite the multitude of evidence on the deteriorating effect of smoking on lung function and lung age, less attention was devoted to the use of such effects as an effective strategy to quit smoking. Therefore, in this study, we aim to determine the predictability of waist circumference (WC) and body mass index (BMI) for pulmonary function and lung age in normal weight young adult smokers and nonsmokers. Methods: One hundred and thirteen smokers and 95 nonsmoker control male students of Taif University were recruited. Pulmonary function tests including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, and forced expiratory flow 25–75% (FEF25–75%) were performed by each student to measure the lung age. Anthropometric measurements included WC and BMI were performed. Results: We found a significant lower mean value of FVC, FEV1/FVC ratio, and FEF25–75% in smokers as compared to mean values of age‑matched nonsmoker students. Furthermore, the results revealed a significant increase in lung age of smokers as compared to that of nonsmoker students. In smoker subjects, FEV1, FVC, and FEF25–75% are correlated negatively with WC of the subject while their lung age correlated positively with WC. Conclusion: There is a significant deteriorating effect of smoking on lung function on lung age. WC appears to be a better predictor of pulmonary function and lung age than BMI in normal weight young adults.