because pulmonary hypertension is so often fatal. If untreated, about half of patients die within three years.
The disease occurs when there's too much resistance in arteries that carry blood to the lungs from the right side of the heart, typically in patients with heart failure, chronic obstructive pulmonary disease and pneumonia. In about 1.5 percent of patients, doctors can't identify a cause.
As of Dec. 14, 205 patients with primary pulmonary hypertension were awaiting lung transplants, making the disease the most common reason for lung transplantation after scarring from pulmonary fibrosis, according to data from the United Network for Organ Sharing.
The new study, led by Chaya Merrill, found hospital admissions for pulmonary hypertension increased more than 50 percent between 1997 and 2005, from 301,400 to 456,500. The average cost for each hospitalization in 2005 was $4,300 higher than the average for all hospital stays, $12,400 versus $8,100