The Science Journal of the American Association for Respiratory Care
Background: Lung age estimation research arose from a desire to create a positive influence in the education of patients attending smoking cessation programs. Morris et. al. developed reference linear regression equations based on components of forced vital capacity measurements in healthy non-smoking adults, aged 20 to 84 years permitting lung age estimation in terms of pulmonary function1. We compared chronologic age and lung age estimates to determine if pulmonary dysfunction associated with smoking is detectable in young adults.
Methods: This study was approved by our institution's Committee on Human Volunteers and informed consent was obtained from every participant. A sample from a population of smoking (n = 5) and non-smoking (n = 9) students 18 - 25 years of age were asked to fill out a questionnaire about their smoking history and undergo pulmonary function testing that included three flow-volume loops. Lung age estimations were calculated by pulmonary function software (Burdick, Inc., Milton, WI) that incorporates linear regression equations developed by Morris et. al1. Comparisons were made between chronological age and lung age estimation of smoking and non-smoking students using a two-tailed student t-test (Excel, Redmond, WA). Statistical significance was set at p
Results: The results (all values Mean ± S.D.) from comparisons showed that non-smokers had no significant difference between chronologic (21.56 ± 1.51 years of age) and estimated (22.89 ± 6.88 years of age) lung age (p = 0.46). However, results from smokers showed a significant chronologic (22.8 ± 1.30 years of age) to estimated (37.6 ± 7.30 years of age) lung age difference (p = 0.01).
Conclusion: Although this study has a small number of participants, the results indicate lung dysfunction as a result of smoking can be detected in young adults. This lung dysfunction manifests as an increase in estimated lung age. The preliminary findings of this study may be applicable in the educational process of young adults enrolled in smoking cessation programs. Further research in this area should result in a stronger argument for the use of lung age estimation in smoking cessation programs involving teens and young adults.
1. Morris JF, Temple W. Spirometric lung age estimation for motivating smoking cessation. Preventive Medicine 1985; 14(5):655-62.