PAH Center

Certain health factors appear to increase an individual's chances of developing PAH. Secondary pulmonary arterial hypertension (SPAH) refers to forms of PAH that result directly from another medical condition. These conditions include:

• HIV/AIDS
• Liver disease, such as cirrhosis
• Connective tissue diseases, such as scleroderma or lupus erythematosus
• Chronic obstructive pulmonary disease (COPD), such as emphysema
• Sleep apnea
• Blood clots in the pulmonary artery
• Sickle cell anemia
• Left-sided heart failure

Primary pulmonary hypertension (PPH) describes cases of pulmonary hypertension in which the underlying cause for high blood pressure in the lungs is unknown or can't be found. In some people with PPH, however, researchers have discovered a genetic defect that can lead to the kinds of changes in the pulmonary artery that are seen in PPH. They believe other genes may be involved as well, suggesting the possibility that the disease may be inherited. Scientists are hopeful that further genetic research into PPH may result in prevention or improved treatments.

Other Possible Causes of PPH / PAH

The following factors also appear to cause an increased risk of developing PPH / PAH:

• Use of cocaine or amphetamines
• Use of the appetite suppressants fenfluramine (marketed as Pondimin), dexfenfluramine (marketed as Redux), and the fenfluramine-phentermine drug combination, known as Fen-Phen. Studies estimate that treatment with these drugs increases a patient's risk of developing PPH / PAH from about 1 to 28 cases per million person-years (one person-year represents a patient treated for one year). Learn more about diet drugs and PPH / PAH.