By Xinhua
Beijing : Conditions of cystic fibrosis patients will get worse when they are exposed to secondhand smoke, with those who have a specific gene being even worse, researchers said in the Journal of the American Medical Association Wednesday.
Cystic fibrosis is an inherited chronic disease that causes thick, sticky mucus to build up in the lungs, leading to life-threatening lung infections and other digestion problems.
Previous studies in poorer clinical outcomes for cystic fibrosis patients exposed to secondhand smoke were inconsistent, so the researchers undertook a retrospective assessment of lung function, stratified by environmental and genetic factors, said Garry R. Cutting, at Johns Hopkins University School of Medicine in Baltimore.
They studied 812 people averaged 19.5 with the disease and found that the lung function of those exposed to secondhand smoke was reduced by about 10 percent compared to those not exposed.
A specific version of a gene called TGFbeta1 doubled the negative effects of secondhand smoke on lung function, accordin to the researchers, who did not look at lung function in those active smokers with the disease.