Death rates rise for idiopathic pulmonary fibrosis

Washington -- Idiopathic pulmonary fibrosis should no longer be considered an orphan disease, according to new research, and that's very bad news. Investigators who examined millions of death records found that mortality rates for the lung disease have increased in recent years and show signs of continuing that upward path.

Mortality rates for idiopathic pulmonary fibrosis have now surpassed those from a number of malignancies including acute myeloid leukemia, multiple myeloma and bladder cancer, according to a study in the Aug. 1 American Journal of Respiratory and Critical Care Medicine.

Between 1992 and 2003, the age-adjusted mortality rate from idiopathic pulmonary fibrosis rose by 28% in men, from 48 deaths per 1 million in 1992 to 61 deaths per 1 million in 2003. Among women the increase was 41%, a rise from 39 deaths per 1 million in 1992 to 55 deaths per 1 million in 2003.

The disease, which inflames and scars tissues deep within the lungs, is deadly. Survival rates after diagnosis are generally three to five years. There is no effective treatment and little understanding about its cause, although smoking has been implicated.

Part of the increase is thought to be the result of better detection of the illness, said the researchers. "In the 1990s the technology improved and high resolution CT scans may have led to more clinical recognition of the disease," said lead investigator Amy Olson, MD, MSPH, a research fellow at the University of Colorado Health Sciences Center in Boulder.

But historic smoking patterns may also be a cause, said Dr. Olson, with higher rates of smoking in the past leading to an increase of pulmonary fibrosis today.

There is the possibility that the prevalence of the disease is actually increasing, acknowledged senior investigator Kevin Brown, MD, vice chair of medicine at National Jewish Medical and Research Center in Denver. "But we can't sort out those two possibilities [better detection or higher prevalence] based on the data we have."

Dr. Olson and her colleagues examined the cause of death listed for more than 28 million people in the U.S. and determined that more than 175,000 had died from pulmonary fibrosis.

Mortality for lung diseases on the rise

"What is striking about the finding is that the mortality rates for people with PF seem to be rising for both men and women at a pretty rapid rate," said David Ingbar, MD, president of the American Thoracic Society and director of the pulmonary, allergy and critical care division at the University of Minnesota.

A look at the course of this disease compared with that of other potentially fatal ailments reveals a distressing difference, said Dr. Ingbar. "While the good news is that deaths from cancer, heart disease and strokes are going down ... it is very concerning to me that for a variety of lung diseases, including chronic obstructive pulmonary disease, lung cancer and now pulmonary fibrosis, mortality rates are clearly rising."

Pulmonary fibrosis is "common enough now that primary care physicians should have this in their differential when evaluating patients with respiratory symptoms," said Dr. Olson.

"I think primary care physicians need to start learning about this disease because it is being recognized much more frequently, and clearly the mortality rate is going up," agreed Dr. Ingbar. "It is also important to get patients diagnosed early so they can be counseled properly with their families."

Efforts are being made to find effective treatments for the disease, said Dr. Brown. The National Institutes of Health is funding 12 medical centers across the nation to study idiopathic pulmonary fibrosis. The National Jewish Medical Center is among the funded centers. Duke University in Durham, N.C., is coordinating the project. The centers are charged with developing and conducting clinical trials to identify better therapies.

"We have a lot of hope that we are going to make a treatment breakthrough in the next few years," said Dr. Brown.