WEDNESDAY, Jan. 18, 2006 (HealthDay News) -- Researchers believe they've found a way to clear the thick mucus from the lungs of people with cystic fibrosis so they will be less vulnerable to life-threatening infections.
The idea is to induce a slick, watery surface to the airways so that this mucus can slide away, explained Dr. Richard C. Boucher, director of the Cystic Fibrosis Pulmonary Treatment and Research Center at the University of North Carolina, Chapel Hill.
His group, along with researchers in Australia, is achieving that goal by having cystic fibrosis patients inhale a concentrated salt solution.
But that's just the beginning, he said.
"We have provided a road map for future therapies designed to hydrate the airway surface," Boucher said. "It is not perfect, but it has laid the groundwork for development of better therapies."
Two reports on use of "inhaled hypertonic saline," the formal name for a salt solution, at North Carolina and in Australia, appear in the Jan. 19 issue of the New England Journal of Medicine. The number of patients involved in the studies is small -- 24 patients in North Carolina study, 164 in the Australian cohort -- but both groups are reporting a significant reduction in lung problems associated with mucus removal.
"They had fewer troubling symptoms such as wheezing," said Dr. Scott H. Donaldson, an associate professor of medicine and lead researcher for the North Carolina team. They also had markedly improved breathing capacity, he said.
Cystic fibrosis is an inherited disease affecting approximately 30,000 Americans. Its major symptoms include the accumulation in the airways of thick, clogging mucus that becomes a breeding ground for germs. Use of antibiotics and intense therapy has extended the once-short life span of cystic fibrosis patients, but most still won't live past the mid-30s.
Experts have long debated the cause of mucus accumulation and how to prevent it, Boucher said. However, work in the laboratory, and then with mice and humans, has shown that "dehydration is the critical factor" and that coating the airways with a thin film of water lets the mucus slide away.
The treatment now is being used routinely for adults treated for cystic fibrosis at the University of Carolina, Donaldson said. They generally inhale the salt solution twice a day, although "four times a day gets better results," he said.
But the real hope is for people newly diagnosed with the condition, Donaldson said. "Regular use of the agent at a very early stage of lung disease may prevent infections and add years of life," he said. Meanwhile, research into better ways to hydrate the airways is ongoing, Boucher said.
"The overall concept is very exciting," said Dr. Felix Ratjen, head of respiratory medicine at the Hospital for Sick Children in Toronto. However, he cautioned that there still are blanks to be filled in.
"It needs to be proven that if you do it in patients with less severe early disease, it will stop the progression of the disease," Ratjen said. "There is no data on how it will be tolerated early."
Also, it still has to be shown whether the beneficial effects reported in these trials will be sustained over time, he said.
"It also needs to be sorted out how you can make it work better," Ratjen said. "This [the inhaled salt solution] is a relatively crude approach. But, because it is a very simple concept, it is very attractive."
More information
Find out more about cystic fibrosis at the National Library of Medicine.
