Pulmonary Function Tests and Their Reversibility in Smokers


Department of Physiology, Ghaem Medical Centre, Mashhad University of Medical Sciences and Health Services, MASHHAD-IRAN


ABSTRACT Background: Smoking is known as the major cause of chronic obstructive pulmonary disease (COPD). In COPD, most of pulmonary function tests (PFTs) specially those indicating the diameter of airways are reduced. There are reports that bronchodilator drugs have no or a very little effect on PFT of COPD patients. Therefore, in this study PFTs of smokers were compared with those of nonsmokers, and the effect of bronchodilator inhaler (salbutamol) on PFTs of smokers were also examined. Materials and Methods: Pulmonary function tests were measured in 97 male smokers (height 171.71±6.68 cm, age 36.49±13.06 years old) and compared with 95 male nonsmokers (height 171.79±8.81 cm, age 35.56±12.83 years old). The subjects underwent measurement of spirometric flow and volume. The following variables were measured: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), peak expiratory flow (PEF), maximal expiratory flow at 75%, 50%, and 25% of the FVC (MEF75, MEF50, and MEF25 respectively). In addition, pulmonary function tests of 33 male smokers (height 172.79±11.94 cm, age 38.30±6.65 years old) before and 10 minutes after administration of 200 µg salbutamol inhaler were measured. Results: The results showed that most values of PFTs in smokers were significantly lower than those of non-smokers (p