Sickle cell disease, a type of inherited anemia (shortage of healthy red blood cells), is characterized by abnormally shaped red blood cells. Named for the sickle, or crescent shape, of the abnormal blood cells, the sickle cells aren’t as flexible as normal blood cells. That means they easily break or get stuck in blood vessels.  

The condition can cause life-long complications to many organs in the body, including the lungs. Some studies suggest that PH is the greatest risk factor for death among aging patients with sickle cell disease.  

PH can occur in several ways in sickle cell disease, such as problems with the left side of the heart, obstructive sleep apnea (problems with breathing during sleep) and blood clots in the lungs.  

However, the most concerning cause of PH in sickle cell disease is related to blood vessels in the lungs. Recent autopsy studies suggest that up to 75% of sickle cell patients have changes in the lung blood vessels at the time of death, signifying the presence of PH or alterations that can cause PH.  

One possible explanation is that the increased breakdown of red blood cells within the blood vessels in the lungs causes inflammation and reduces nitric oxide (a substance that causes blood vessels to relax). That causes small arteries in the lungs to constrict and narrow, leading to PH.  

Screening for sickle cell disease-related PH  

PH symptoms include: 

• Shortness of breath with activity 

• Increased fatigue 

• Swelling of the ankles, legs or abdomen 

• Chest discomfort or pain 

• Light-headedness and fainting 

In sickle cell disease, those symptoms can be mistakenly attributed to other problems, particularly anemia associated with sickle cell disease. Because PH symptoms initially can be mild, it is important for people with sickle cell disease to share any of those symptoms with their doctors.  

People with sickle cell disease are more likely to develop PH, and those who suffer from PH are at higher risk of death than those without PH. Your doctor may want to perform screening tests to make sure you don’t have PH, even if you don’t have symptoms.

Treatment options  

Current guidelines and the Pulmonary Hypertension Association recommend that PH specialists work with sickle cell doctors to evaluate every person whom they suspect of having PH. The patient must have a right heart catheterization, which helps physicians determine appropriate treatment as well as the cause and severity of the patient’s PH.  

Regardless of the type of PH you have, PHA recommends you receive the best possible treatment for your sickle cell disease. Sometimes that includes the medication hydroxyurea or chronic blood transfusions.  

It is important to screen for and treat other causes of sickle cell disease-associated PH, such as blood clots in the lungs and obstructive sleep apnea. Controlling your sickle cell disease and other problems that contribute to PH can help prevent your PH from worsening.  

While there are no drugs approved specifically to treat sickle cell disease-associated PH, patients with PH attributed to the blood vessels of the lungs may respond to medications that have benefited patients with Group 1 (pulmonary arterial hypertension, or PAH).  

No matter what treatments your doctor recommends, you should continue to follow up with your health care team to monitor your progress throughout treatment.  

Download or order a brochure

Information on PH and Sickle Cell Disease is one of a series of PH& brochures available to download as a PDF or to order as a printed brochure. 

PH & Sickle Cell Disease