Pulmonary fibrosis is an inflammatory disease that results in scarring, or fibrosis, of the lungs. Over time, the fibrosis can progress such that the lungs can no longer deliver oxygen to the body's tissues. Although physicians often prescribe a combination of anti-inflammatory and immunosuppressive therapies, the only clearly effective treatment is lung transplantation.
Last year, a treatment that had shown early promise in alleviating symptoms and preventing the advance of pulmonary fibrosis failed to stall the disorder's progression in 162 patients.
"Therapies that have been tested in clinical trials have not proved effective," Steele said. "We need to identify new directions.
"We've known for some time that idiopathic interstitial pneumonia can run in families," he added. "Currently there is no adequate animal model to study the disease. Therefore, we can use genetics to dissect the causes and mechanism of the disease."
The researchers evaluated 111 families in which at least two relatives had been diagnosed with IIP. The sample included 309 people with the disease and 360 unaffected relatives.
The disease disproportionately affected siblings and also showed a pattern of transmission from parent to child in many families, the team found. Older people, males and those who had smoked cigarettes also showed a greater risk of developing IIP, they reported.
The team found that cigarette smoking had an important independent effect on disease risk. Those with a history of smoking had a 3.6-fold greater chance of getting the disease, they found.
"While the importance of cigarette smoking in the progression of idiopathic pulmonary fibrosis remains controversial, case control s
Contact: Kendall Morgan
Duke University Medical Center