PH and Sickle Cell Disease
- I have sickle cell disease. My doctor wants to screen me for pulmonary hypertension. Why is this?
- What are some of the symptoms of pulmonary hypertension?
- Why is it so important to screen for PH now?
- If a doctor determines that I have PH, what’s the next step?
I have sickle cell disease. My doctor wants to screen me for pulmonary hypertension. Why is this?
Sickle cell disease (SCD), a type of anemia (shortage of red blood cells), is characterized by abnormally shaped red blood cells. Sickle cells (named for the sickle, or oblong, slender shape of the malformed blood cells) have decreased flexibility, meaning they break easily. This results in a number of life-long complications.
PH is an increasingly recognized complication of SCD. Studies show that approximately 30% of screened adult patients with SCD develop mild PH in adulthood. In 10% of patients, the PH is more severe. Recent autopsy studies also suggest that up to 75% of sickle cell patients show changes in the lung tissue at the time of death, indicating the existence of pulmonary arterial hypertension (PAH).
One possible reason sickle cell patients seem to be at risk for developing PH is that increased breakdown of red blood cells within the blood vessels causes inflammation and a decrease of nitric oxide (a substance that causes relaxation of the blood vessels). This causes constriction of the small arteries of the lungs which may lead to PH.
What are some of the symptoms of pulmonary hypertension?
Because they are somewhat general symptoms, the characteristics of PH felt by the patient often are mistakenly attributed to other problems. These symptoms include shortness of breath, feeling fatigued, being unable to tolerate increased levels of exercise, unexplained swelling of the ankles, legs, abdomen or arms, chest discomfort or pain, light-headedness and fainting. Your doctor wants to make sure you do not have symptoms that are being overlooked.
Why is it so important to screen for PH now?
Individuals who suffer from SCD are more likely to develop PH, and those who suffer from PH in addition to SCD are at a higher risk of death than that of SCD patients without PH. Therefore, your doctor wants to test your pulmonary pressure to make sure you’re not currently affected by PH. If PH is present, he or she will want to begin treatment immediately to control both your SCD and your PH.
Studies from the National Heart, Lung and Blood Institute suggest that PH is the greatest risk factor for death in the aging population of patients with SCD. An echocardiogram is an important screening tool to check for the development of PH in patients with problems like SCD. The echocardiogram can also help to determine the cause of the high pulmonary pressures.
If a doctor determines that I have PH, what’s the next step?
Because SCD is a complex disorder with many complications, no specific clinical guidelines have been written for patients who have both SCD and PH. Researchers do not know exactly what role PH plays in the worsening of disease.
The National Institute of Health recommends that each case of PH be evaluated by a specialist, and assigned a value, from mild to severe. The therapy used to treat various gradations of the disease will likewise increase or decrease, depending on the severity.
A number of different treatments are available, and have been shown to be very effective. Your doctor will help determine the best treatment for you, and will continue to monitor your progress throughout your treatment. Specialists at a PH center can also help guide you through the process and answer your questions.