Pulmonary arterial hypertension (PAH) is a specific type of pulmonary hypertension that is caused when the tiny arteries in your lung become thickened and narrowed. This blocks the blood flow through your lungs which raises the blood pressure in the lungs and causes your heart to work harder to pump your blood through those narrowed arteries. Over time, your heart loses the ability to effectively pump blood throughout your body.
- Pulmonary arterial hypertension (PAH) is a rare, progressive disorder (meaning it gets worse over time), in which the cause is usually unknown.
- PAH is most common in women between the ages of 30-60.
- There is no cure for PAH, but treatments are available to control symptoms and improve quality of life.
- PAH is referred to as Group 1: PAH among the five types of pulmonary hypertension.
- About 500-1000 new cases of PAH are being diagnosed each year in the U.S.
What Causes Pulmonary Arterial Hypertension?
The exact cause of PAH is unknown. It is unlike other forms of pulmonary hypertension, where high blood pressure in the lungs is caused by underlying heart or lung disease. Researchers believe that PAH occurs when there is injury to the cells that line the blood vessels of the lung, which over time results in this blood vessel disease. If the cause of this change is unknown it is referred to as idiopathic PAH. If the change is believed to be caused by a genetic mutation it is called heritable PAH. Approximately 15-20% of PAH patients have heritable PAH.
Other conditions that are associated with the development of PAH include: connective tissue disorders like scleroderma and lupus; exposure to certain toxins and drugs, including methamphetamine and cocaine; infections, including HIV and schistosomiasis; cirrhosis of the liver; and congenital heart abnormalities.
Who Is at Risk?
Pulmonary arterial hypertension is more frequent in women between the ages of 30 and 60 and disproportionately impacts African American and Hispanic women. Since there is an inherited form of PAH, a family history of the disease may put you at increased risk.
Reviewed and approved by the American Lung Association Scientific and Medical Editorial Review Panel.
Page last updated: June 8, 2023