MONDAY, Dec. 7 (HealthDay News) -- People who have asthma and who also smoke could reverse some of the damage to their lungs by saying no to cigarettes, new Dutch research suggests.

"We found that exposure to cigarette smoke appears to increase the thickness of the epithelium, or lining, of the airways in the lung," Martine Broekema, lead author of the study and a researcher at the University of Groningen in the Netherlands, said in a news release from the American Thoracic Society. "This may be the underlying cause of the fact that smoking asthma patients experience more asthma symptoms, such as shortness of breath and phlegm production, compared to nonsmoking asthma patients."

The researchers looked at 147 people with asthma symptoms, including 35 smokers, 46 ex-smokers and 66 people who had never smoked.

People who currently smoked had more cells that produce mucous than did those who never smoked, the researchers found. "These pathological findings were associated with the severity of phlegm production reported by the asthma patients, suggesting a causal relationship between the two," Broekema said. "Smoking asthmatics also showed a distinct inflammatory profile in their lungs compared to never-smoking asthmatics."

"Furthermore, our data suggest that smoking cessation can reverse the thickening of the lining of the airways," she said.

The findings are published in the Dec. 15 issue of the American Journal of Respiratory and Critical Care Medicine.

In the big picture, "this study shows again how important smoking cessation is for pulmonary health, and this appears to be especially true for asthmatic patients," Broekema said. "The good news is that quitting appears to have a measurable benefit in these individuals."

More information

Learn more about quitting smoking from smokefree.gov.