CIGARETTE SMOKING + PULMONARY FUNCTION IN HEALTHY YOUNG ADULTS

Abstract

Ten healthy young adult males who had never smoked were compared clinically and by the application of pulmonary function and exercise tolerance tests with a similar group who had regularly smoked cigarettes. They were matched for age (20-35 years), physical characteristics, and fitness. They came from the same socioeconomic background. Although 6 of the smokers had cough and sputum, these symptoms were absent in the nonsmokers. In the smokers, vital capacity and total lung capacity (TLC) were less, residual volume [RV] greater, and RV/TLC percentage greater than in nonsmokers. The mixing index and nonelastic resistance were higher in smokers and the compliance, lower. The heart rate was more rapid at rest and during exercise in smokers, and arterial oxygen saturation was lower during strenuous exercise. By the statistical technique of discriminant analysis, physiologic indices for smokers and nonsmokers were obtained, using the following variables: vital capacity, RV/TLC percentage, compliance, nonelastic resistance, and arterial oxygen saturation and heart rate during exercise. The difference between the means of these indices was significant at the 99% level. Cigarette smoking alters pulmonary function in the direction of chronic obstructive lung disease within the first 15 years after commencing the habit, and adversely affects the cardiovascular system.