Researchers Explore Rare Lung Disorder

Abstract

SEEKING TO ENABLE RESEARCHERS and clinicians to share experiences and ideas regarding a relatively rare—and, so far, incurable— condition, the National Institutes of Health (NIH) sponsored its first international meeting on pulmonary arterial hypertension. The December gathering in Bethesda, Md, was designed to be “a forum for learning, scientific discussion, and development of new collaborations that will further the understanding of pulmonary hypertension and hopefully lead to treatment advances for the disease,” said Roberto Machado, MD, an investigator with the Vascular Medicine Branch of the NIH’s National Heart, Lung, and Blood Institute (NHLBI). Pulmonary arterial hypertension, or continuous high blood pressure in the blood vessels of the lungs, is a disabling and ultimately fatal disease affecting people of all ages. Whereas the average resting blood pressure in a normal pulmonary artery is about 14 mm Hg, in people with the disease it is about 25 mm Hg. The increase reflects narrowing or blockage of the arterial passages, which can result from tightening of the muscles within the arterial walls, thickening of the arterial walls, or formation of blood clots within smaller arteries. There are 2 types of pulmonary arterial hypertension. Primary pulmonary hypertension, which is either inherited or sporadic, accounts for about 500 to 1000 cases annually in the United States. Secondary pulmonary hypertension, the more common form, occurs as a result of other conditions such as chronic heart or lung disease, blood clots in the lungs, scleroderma, HIV/AIDS, or sickle cell disease. Pulmonary arterial hypertension is associated with 15 000 deaths annually in the United States, with blacks twice as likely to die compared with whites. It presents most frequently in women aged 20 to 40 years.