If you have pulmonary arterial hypertension (PAH), you may wonder what caused it. PAH can develop as a serious complication of connective tissue diseases (conditions that affect the body’s connective tissues, like skin and joints), such as scleroderma. While scleroderma more commonly causes symptoms like swollen hands and feet, stiff joints, or digestive problems, it can also affect internal organs, including the heart and lungs.

Several members of myPHteam have asked if others have conditions like scleroderma: “Does anyone have an autoimmune issue that caused their PH?”

Another member replied, “My PAH is related to connective tissue disease. I have CREST syndrome (a form of scleroderma), rheumatoid arthritis, and discoid lupus.”

This article explores where scleroderma can appear in the body, what it may look like, and how it’s linked to PAH. It will also cover how doctors such as pulmonologists (lung specialists) and rheumatologists (specialists in autoimmune and connective tissue diseases) can help.

What Is Scleroderma?

Your body’s immune system works hard to protect you from invading bacteria and viruses. When you have an infection, it may kick into overdrive and create inflammation (the body’s natural response to injury or infection) to help kill off the organisms that are making you sick.

However, this process can sometimes go wrong. This happens when your immune system mistakenly targets your own healthy cells, resulting in autoimmune disease (a condition in which the immune system attacks the body itself).

This is what happens with scleroderma, a rare autoimmune disease that can affect the skin, joints, muscles, and internal organs, such as the heart and lungs. Doctors and researchers aren’t quite sure what triggers scleroderma, but they believe it may be related to a combination of genetics, environment, and hormones.

Health experts do know that scleroderma arises when the immune system becomes overactive. This leads to an overproduction of collagen, a protein that helps give structure and support to tissues in the skin, bones, and muscles. Too much collagen can cause tissues to become thick, tight, or stiff, which may lead to symptoms like skin thickening, joint stiffness, and pain.

According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases, scleroderma is more common in women than in men, although people of any sex can develop the condition.

What Are the Types and Symptoms of Scleroderma?

There are two main types of scleroderma:

• Localized scleroderma
• Systemic scleroderma

Localized scleroderma mainly affects the skin and the tissues directly beneath it. Types include morphea scleroderma, which causes oval or round patches of hard, discolored skin, and linear scleroderma, in which the skin thickens in a band or line, often on the arms, legs, or forehead.

Systemic scleroderma (also known as systemic sclerosis) can affect the entire body, including the lungs, heart, digestive system, and kidneys.

Systemic scleroderma has two forms: limited cutaneous scleroderma and diffuse cutaneous scleroderma. They are defined by the areas of the skin affected, which organs may be involved, and certain antibodies (immune system proteins) that appear more often in each type.

Limited cutaneous scleroderma tends to develop slowly and is generally milder than the diffuse form. It affects the skin covering the face, hands, fingers, lower arms, and lower legs. This condition is also referred to as CREST syndrome, an acronym that stands for:

• Calcinosis — A buildup of calcium deposits in connective tissues
• Raynaud’s phenomenon — A condition that causes the tiny blood vessels in the hands or feet to contract (tighten) in response to cold or stress
• Esophageal dysfunction — Trouble swallowing due to changes in the esophagus
• Sclerodactyly — Thickening and tightening of the skin on the fingers
• Telangiectasia — Small, widened blood vessels that appear as red or purple spots, often on the face or hands

Diffuse cutaneous scleroderma symptoms, on the other hand, often develop more quickly. People may first notice thickened skin on their fingers and toes, which can then spread to the arms, legs, and trunk. This type of scleroderma is associated with more internal organ involvement, including the lungs.

How Is Scleroderma Related to PAH?

In PAH, blood pressure is higher than normal in the pulmonary arteries (the blood vessels that carry blood from the heart to the lungs). Over time, this increased pressure can strain the right side of the heart and may lead to right-sided heart failure.

Several factors can contribute to the development of PAH, including:

• Certain medical conditions
• Genetic mutations (changes in genes)
• Exposure to some drugs or toxins

According to data from major PAH registries cited by the World Health Organization (WHO), idiopathic PAH (PAH with no clearly identified cause) and heritable PAH (PAH linked to inherited genetic changes) together account for approximately half of PAH cases. The remaining cases are linked to underlying health conditions, including scleroderma. Connective tissue diseases are the most common cause of associated PAH, which is PAH that develops as a result of another medical condition.

About half of the cases of PAH are caused by an underlying health condition like scleroderma.

Research suggests that about 5 percent to 15 percent of people with systemic scleroderma develop PAH. Systemic scleroderma can contribute to PAH by damaging blood vessels and organs such as the heart and lungs. This damage can cause blood vessels to narrow and stiffen, leading to higher pressure in the pulmonary arteries.

Other forms of pulmonary hypertension can develop in people with scleroderma due to interstitial lung disease (lung scarring), which makes it harder for blood to flow through the lungs and raises pressure in these arteries.

If you’re living with scleroderma, it’s important to be aware of common PAH symptoms. Early on, PAH may be mild and not cause noticeable symptoms. As the disease progresses, some people begin to experience symptoms like:

• Fatigue (extreme tiredness that doesn’t improve with rest)
• Shortness of breath, especially during activity
• Chest pain or pressure
• Dizziness or fainting
• Edema (swelling) in the legs and feet, which can be a sign of heart strain or heart failure (when the heart doesn’t pump as much blood to meet the body’s needs)
• A pounding or racing heartbeat
• Hoarseness or a persistent cough

Early cases of PAH in scleroderma may not cause symptoms.

Screening for PAH in People With Scleroderma

It’s important to talk with a healthcare provider if you have scleroderma and experience possible PAH symptoms, such as shortness of breath, fatigue, chest pain, and swelling in the legs, arms, or ankles. A doctor can perform a physical exam and order additional tests to better understand what may be causing your symptoms.

According to the Pulmonary Hypertension Association, people with scleroderma are advised to be screened for PAH every year. Screening tests for PAH include:

• An echocardiogram (an ultrasound of the heart)
• Pulmonary function tests (which measure how well the lungs work)
• Other imaging or blood tests

The most accurate test for diagnosing PAH is right heart catheterization, a procedure that uses a thin, flexible tube to measure pressure inside the pulmonary arteries. Because this test is invasive, it’s typically done only in specific situations, based on a healthcare provider’s judgment.

Finding PAH earlier can improve treatment options and long-term outcomes, which is why regular screening is so important for people living with scleroderma.

What Are the Treatments for PAH in Scleroderma?

PAH in scleroderma may be treated with diuretics (medications that help remove extra fluid), supplemental oxygen, and PAH-specific medications. Your doctor, pulmonologist, and rheumatologist can work together to create the best treatment plan for you.

One myPHteam member asked others, “Does anybody else have PAH related to scleroderma? And if so, what medications do you take to treat both diseases?”

“Does anybody else have PAH related to scleroderma? And if so, what medications do you take to treat both diseases?”

— A myPHteam member

If you have scleroderma and PAH, your doctor may prescribe medications that lower pulmonary blood pressure, called pulmonary vasodilators (drugs that help blood vessels relax and widen). These drugs can help improve blood flow in the lungs and may also treat Raynaud’s phenomenon.

There are many other drugs used to target PAH pathways and symptoms. Drug classes include:

• Phosphodiesterase 5 (PDE5) inhibitors
• Prostacyclin pathway agents
• Endothelin receptor antagonists
• Activin signaling inhibitors
• Soluble guanylate cyclase stimulators

Talk to Your Doctor

If you’re living with scleroderma, it’s important to be aware of how the condition can affect your lungs and overall health. PAH may not cause obvious symptoms at first, but catching it early can make a big difference.

If you notice new or worsening signs like shortness of breath, fatigue, or swelling in your legs, talk to your doctor. Working with a care team that includes both a rheumatologist and a pulmonologist can help you find the right treatment plan to manage both conditions and improve your quality of life.

Join the Conversation

On myPHteam, people share their experiences with pulmonary hypertension, get advice, and find support from others who understand.

Are you living with scleroderma and pulmonary arterial hypertension? What symptoms do you experience? What treatments have helped you manage these conditions? Let others know in the comments below.