What Causes Pulmonary Arterial Hypertension?

Certain factors appear to increase your chances of developing pulmonary arterial hypertension (PAH). They include:

• Use of appetite suppressants, especially fenfluramine (fen-FLOO-ra-men) and dexfenfluramine (deks-fen-FLOO-ra-men)
• Chronic use of cocaine or amphetamines
• HIV infection
• Liver disease
• Connective tissue diseases, such as scleroderma or lupus erythematosus

Doctors do not know what causes primary pulmonary arterial hypertension (PPAH), although it is inherited in some people. Recently, researchers discovered a defect in a gene that can lead to changes in the pulmonary arteries like those seen in PPAH. They think that other genes may be involved as well. As we learn more about how different genes work in the development of PPAH, better treatments and perhaps a preventive treatment or cure will be found.

Secondary pulmonary arterial hypertension (SPAH) is caused by a variety of conditions. Chronic obstructive pulmonary disease is the most common cause in adults.

Other Conditions That Can Lead to SPAH

• Obstructive sleep apnea
• Congenital heart defects
• Chronic blood clots in the pulmonary artery

PAH affects men and women of all ages, from very young children to seniors, and people of all racial and ethnic backgrounds.

PPAH is most common in women in their thirties and men in their forties. Twice as many cases are reported in women as in men.