Background: The aim of the present study was to investigate the effect of exposure to hookah smoke on the respiratory capacity of employees working in hookah cafes in Bandar Abbas. Methods: A total of 75 employees of hookah cafes and 64 people in the control group were the target population. Participants without a history of smoking, diabetes, and hypertension were included in the study. First, the height and weight of subjects were measured and then a respiratory test was performed by an occupational medicine specialist. At the same time, a checklist was completed, which contained demographic characteristics, history of working in hookah cafes, pulmonary diseases, hypertension, smoking, exercising, and a second job. Results: The mean age of the case and control groups was found to be 31.41 and 30.73 years, respectively. The mean values of the indices in the case and the control groups were as follows: forced expiratory volume (FEV1): 84.4% and 89.9%, forced vital capacity (FVC): 91.5% and 91.1%, forced expiratory flow 25-75 (FEF25-75): 78.7% and 75.9%, and peak expiratory flow (PEF): 87.2% and 95.2%, respectively. A significant relationship was found between exposure to hookah smoke and the lung capacity of employees working in hookah cafes (P <0.001). Conclusion: Based on the findings of the study and in order to reduce passive exposure to hookah smoke and its negative consequences, officials should review and apply strict rules on hookah use and monitor and control the air quality inside hookah cafes.

Background: Forced expiratory volume in 6 seconds (FEV6) is a reliable substitute for forced vital capacity (FVC) to identify pulmonary diseases. This study aimed to determine the diagnostic performance of FEV6 in the detection of obstructive and restrictive spirometric patterns. Methods: In this cross-sectional study, spirometry was performed on patients referred to the occupational medicine clinic of Shahid Mohammadi Hospital, Bandar Abbas, Iran, 2018. Spirometric parameters, including FEV1, FVC, and FEV6, were recorded for those tests meeting the American Thoracic Society (ATS) standards. Taken as the reference, the FEV1/FVC ratio<70% indicated airway obstruction, and the restrictive pattern was defined as FVC<80%. Results: In general, 1100 spirometries were included after meeting the ATS standards. The optimal cut-off of FEV1/FEV6 for the prediction of airway obstruction was 71.45% with a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of 97.22%, 98.22%, 89.17%, 99.57%, and 98.09%, respectively. The best cut-off of FEV6 for the prediction of the restrictive pattern was 79.23% with the corresponding diagnostic indices of 97.29%, 99.05%, 94.11%, 99.57%, and 98.81%, respectively. Based on the FEV1/FEV6 cut-off, the frequency of obstruction was 14.27% (157/1100) compared to 13.09% based on FEV1/FVC. The frequency of restriction was 13.90% (153/1100) according to the FEV6 cut-off compared to 13.45% with respect to FVC. Conclusion: Overall, our results indicated the applicability of FEV1/FEV6 as an accepted surrogate for FEV1/FVC to diagnose airway obstruction, particularly to screen for chronic obstructive pulmonary disease (COPD) among high-risk patients. In addition, FEV6 is potentially an appropriate substitute for FVC to detect a restrictive pattern.