Pulmonary arterial hypertension (PAH) is a disease that’s not very well known among the general population. If you or a loved one has been diagnosed with PAH, you likely have plenty of questions — for starters, is PAH a rare disease?

Yes, pulmonary arterial hypertension is rare. This lung disease is a form of pulmonary hypertension (PH). The blood vessels in the lungs become thick and narrow, which leads to high blood pressure. In people with PAH, the heart’s right ventricle needs to work harder to pump blood into the arteries of the lungs. This type of PH raises the risk of right heart failure, blood clots, and other types of heart disease.

Although there’s no cure for PAH, timely and regular care from medical specialists who treat PAH (cardiologists, pulmonologists, rheumatologists, and more) can help slow disease progression and improve quality of life.

Below, we offer more details that answer the question “Is pulmonary arterial hypertension rare?” and discuss other less-known facts about PAH. Read on to learn more about this condition and get the care you need.

1. PAH Is a Very Rare Disease

PAH is a rare condition that affects about 15 to 55 people per million worldwide. Each year, from 500 to 1,000 new cases of PAH are diagnosed in the United States. About 15 percent to 20 percent of PAH cases are hereditary — known as heritable PAH — and linked to a family history of the disease.

Each year, from 500 to 1,000 new cases of pulmonary arterial hypertension are diagnosed in the United States.

About 30 percent of PAH cases are associated with connective tissue disease, which can damage blood vessels. PAH can also be linked to congenital heart disease.

Among the different forms of PAH are:

• Heritable PAH (formerly known as familial PAH or genetic PAH) — As noted, this refers to PAH inherited from a relative with the condition.
• Associated PAH — Some people develop PAH when they have another medical condition, such as connective tissue disease, congenital heart disease, liver disease, or HIV.
• Idiopathic PAH — This is a type of PAH with an unknown cause (responsible for more than half of all cases).

There are different ways to treat PAH, depending on the type and underlying cause. For someone with associated PAH, it’s important to also manage the other health issue. For example, people with PAH linked to scleroderma (systemic sclerosis, a type of connective tissue disease) tend to respond less well to standard PAH treatments and may face more serious outcomes. Scleroderma can affect the vascular system and damage blood vessels, contributing to the development and progression of pulmonary arterial hypertension.

2. An Accurate PAH Diagnosis Can Take Several Years

PAH diagnoses are often delayed. The condition can be difficult to diagnose, and getting a proper diagnosis can take up to two or three years. A 2020 study in the journal Respirology showed that one-third of people with PAH waited more than two years for a diagnosis, and another 25 percent had a delay of almost three years.

One myPHteam member wrote, “While I certainly feel discouraged with my newest diagnosis, I am relieved to have something that confirms all of my heart and lung symptoms.”

One-third of people with PAH waited more than two years for a diagnosis, and another 25 percent had a delay of almost three years.

“I also struggled to get a diagnosis,” another member said. “So, go to a pulmonologist right away. By the way, you are not crazy — this is a rare and difficult disease to diagnose.”

The consequences of delayed diagnosis are serious. The Respirology study findings showed that people with PAH who waited more than two years for an accurate diagnosis experienced worse outcomes compared with those who were diagnosed sooner. A delay of more than two years was associated with an 11 percent higher risk of death.

Symptoms of PAH, such as shortness of breath, chest pain, and fatigue (tiredness that doesn’t improve with rest), also appear in several other health conditions. Many doctors aren’t trained to recognize signs of PAH, so diagnosis is often delayed.

3. Females Have a Higher Risk of PAH Than Males

According to a study in Methodist DeBakey Cardiovascular Journal, females are almost twice as likely as males to develop PAH​​​​. That ratio lessens among older people, per the study: Females over 65 are only 20 percent more likely than males to develop PAH.

The authors of an AJMC study noted that because younger women have a higher rate of PAH, researchers believe sex hormones may be linked with PAH.

4. Race and Ethnicity May Play a Role in a Person’s Type of PAH

Although more research is needed on this topic, some studies have found differences in types of pulmonary arterial hypertension across racial and ethnic groups. Understanding racial and ethnic differences in these types can further help doctors in creating specialized PAH treatment plans.

A review of several studies found that PAH types varied across racial and ethnic groups. The results showed that among people with pulmonary arterial hypertension:

• African Americans were more likely to have connective tissue disease-associated PAH — that is, linked with scleroderma, rheumatoid arthritis, systemic lupus erythematosus, or mixed connective tissue disease.
• Hispanic people were more likely to have congenital heart disease-associated PAH.
• Non-Hispanic white people were more likely to have PAH linked with drug or toxin use. They were also more likely to have the familial type.

5. Socioeconomic Status May Be a Factor in PAH Rates

Socioeconomic status — a measure made up of factors such as occupation, income, education level, and place of residence — may play a role in PAH outcomes. Lower socioeconomic status is linked to inadequate health insurance, delayed diagnosis, and a lack of follow-up care.

One systematic review led authors to recommend that socioeconomic status be included as a variable (factor) in research on pulmonary arterial hypertension. The study found that people with PAH and a lower income came to healthcare centers with more advanced disease. Diagnosing PAH before it becomes advanced is important for improving treatment outcomes.

Environmental risk factors related to low socioeconomic status, such as high levels of air pollution, exposure to environmental toxins, and lower-quality diet, may also contribute to poorer outcomes from PAH. Researchers have recommended that healthcare professionals become better educated on the risks associated with lower socioeconomic status to help ensure that appropriate PAH treatment is offered.

6. PAH Outcomes Have Greatly Improved in Recent Years

In recent decades, better management of PAH has significantly increased survival rates among people living with the disease. The one-year survival rate is now between 86 percent and 90 percent, up from 65 percent in the 1980s, according to the Journal of Investigative Medicine. Average long-term survival during that period increased from 2.8 years to 6 years.

In recent decades, better management of PAH has significantly increased survival rates among people living with the disease.

A number of medications, such as prostacyclin drugs, can help reduce PAH symptoms. In some advanced cases of PAH, a lung transplant may be advised.

Meanwhile, standards for diagnosis and disease management have also improved with tests such as:

• Right heart catheterization, a procedure that directly measures blood pressure in the heart and lungs
• Echocardiogram, an ultrasound that shows how well the heart and its valves are working
• Other types of lung and heart imaging, such as chest X-rays
• Blood tests, which can evaluate blood flow in the heart and lungs and determine problems with the right side of your heart

Pulmonary function tests might also be done to see how well your lungs are working. These tests are commonly used to evaluate types of pulmonary hypertension and other lung diseases, such as chronic obstructive pulmonary disease (COPD).

Risk-assessment tools help monitor disease progression and provide essential information that can guide PAH treatment plans. People with PAH should see a healthcare provider every three to six months to have their lung function and overall health checked.

Check In With Your Doctor

Your provider is your best guide on your journey with PAH. They can answer your questions about symptoms (such as shortness of breath or edema) and treatment side effects. Working together, you and your doctor can ensure that you have the best quality of life possible while living with PAH.

Talk to People Who Understand

On myPHteam, the social network for people with pulmonary hypertension and their loved ones, more than 56,000 members come together to ask questions, give advice, and share their stories with others who understand life with pulmonary hypertension.

Are you living with pulmonary arterial hypertension? Were you aware of how rare this condition is? How does PAH affect your life? Share your thoughts and experience in the comments below, or share your story on your Activities page.