Secondhand smoke worsens lung function in people with cystic fibrosis, especially those with a specific gene, according to researchers at Johns Hopkins University School of Medicine.

The new research, which was reported by Reuters and an article in MedScape, shows how genetic and environmental factors can interact to harm lung function in CF patients. The study of 812 people included 188 who were exposed to secondhand cigarette smoke at home. The average age of the participants was 19. Dr. Gary Cutting is the study's lead author.

Lung function in those exposed to secondhand smoke was reduced by about 10 percent compared to those not exposed, the researchers found. Lung function was determined by how much air a person could breathe out in the first second of expiration.

Preston W. Campbell, III, M.D., executive vice president for medical affairs of the Cystic Fibrosis Foundation, was quoted in Medscape: "The Cystic Fibrosis Foundation has focused on secondhand smoke for some time, and Dr. Cutting's study is the best study to date. This study gives the CF Foundation evidence-based data for their work against smoking."

Click here to read the Reuters story.

To access the Medscape story, you must register on their Web site at: www.medscape.com.