Bronchiolitis in young female smokers

Abstract

Background: Smoking is a growing concern among young women. However, the pulmonary effects of smoking in young female smokers in their 20's are unknown.

Objective: The purpose of this study was to determine whether young female smokers demonstrate smoking-related lung abnormalities such as bronchiolitis in their 20's.

Methods: We recruited young females (20-30 yr) from Izmir, Turkey; 29 smokers and 31 lifetime non-smokers. They were all asymptomatic. All subjects performed complete lung function measurements and underwent thoracic computed tomography (CT) scanning at suspended full inspiration using a Toshiba "Aquilion" multi-slice CT scanner. The CT images were analyzed using custom software (Emphylx-J) and published equations to calculate total lung volume, mean lung density, lung mass, and the extent of emphysema. CT images were also read semi-quantitatively for respiratory bronchiolitis and emphysema by 2 experienced chest radiologists. When there was substantial difference in scoring, a 3rd (independent) radiologist read the CT scans. Plasma biomarkers of smoking were also measured in these subjects.

Results: Although none of the subjects demonstrated emphysema on CT images, 41% of smokers (compared with only 15% of non-smokers) had evidence for respiratory bronchiolitis (with a score of 2 or more; p = 0.0301). There was a significant relationship between pack-years of smoking and the severity of respiratory bronchiolitis in smokers. Plasma interleukin (IL)-6 levels were also higher in smokers than in non-smokers (p = 0.028). Quantitative analysis for emphysema or airways disease on CT scans did not reveal any significant differences in the two groups with the exception of lung mass, which was higher in the smokers than in non-smokers. Lung function was similar between the two groups.

Conclusion and clinical relevance: Young female smokers in their 20's and 30's demonstrate CT changes consistent with respiratory bronchiolitis and elevated plasma IL-6 levels. They also have "heavier" lungs compared with lifetime non-smokers. These data indicate that pathologic changes of smoking occur early in young female smokers in the absence of demonstrable airflow limitation or symptoms. Public health efforts to curb smoking in young women are clearly needed to reduce the burden of smoking related lung disease in women.