Airways Compared in Smoking, Nonsmoking Asthma Patients
Ex-smokers and never-smokers with asthma had similar airways, providing a reason to quit
FRIDAY, Dec. 11 (HealthDay News) -- Smokers with asthma have significantly greater epithelial changes in their airways than asthma patients who have quit smoking or have never smoked, according to a study in the Dec. 15 issue of the American Journal of Respiratory and Critical Care Medicine.
Martine Broekema, Ph.D., of the University Medical Center Groningen in the Netherlands, and colleagues compared bronchial inflammation and remodeling in 147 subjects with asthma who had never smoked, were ex-smokers, or were current smokers. The subjects were assessed for lung function, exhaled nitric oxide levels, induced sputum, bronchial epithelium, and self-reported symptoms.
The researchers found the smokers with asthma to have lower forced expiratory volume in one second and lower alveolar and bronchial nitric oxide levels than subjects who had never smoked. They also had thickened epithelial tissue, a higher proliferation rate of basal epithelium, and more mucus-positive epithelium and goblet cells than subjects who were ex-smokers or had never smoked. Smokers also had more mast cells and fewer eosinophils than those who had never smoked. Ex-smokers and those who had never smoked had similar numbers of goblet cells and mucus-positive epithelium, epithelial thickness, epithelial proliferation rate, and mast cell numbers.
"Smokers with asthma have epithelial changes that are associated with increased asthma symptoms, such as shortness of breath and phlegm production. The fact that epithelial characteristics in ex-smokers are similar to those in never-smokers suggests that the smoke-induced changes can be reversed by smoking cessation," the authors write.
Two study authors reported receiving consulting fees, lecture fees or grant support from pharmaceutical companies, or serving on their advisory board; one author reported receiving money for participating in an Alair study from Asthmatx.