Researchers link blood protein to severe pulmonary arterial hypertension

A new study from researchers at Johns Hopkins Medicine in Baltimore may have found a link between a blood protein and pulmonary arterial hypertension and how patients could be tested for it.

The study, published June 2 in the American Journal of Respiratory and Critical Care Medicine,  was led by Allen Everett, a professor of pediatrics and the director of the Pediatric Proteome Center at the Johns Hopkins University School of Medicine. 

Everett and his team found that high levels of hematoma derived growth factor (HDGF), a protein found in blood, is linked to worsening an individual’s pulmonary arterial hypertension condition.

“This has the potential to be a much more specific readout for the health of the lungs than what we currently measure using invasive cardiac catheterization,” Everett said in a statement. “It could really have value in making decisions about when to escalate therapy and when to ease it because at present, it’s difficult to determine whether someone’s disease is getting better or worse, especially in children.”

The study compared blood samples from 39 patients with severe pulmonary arterial hypertension to a control group of 39 patients who were of the same age, gender and race. Results showed that protein levels in the experimental patients were about seven times higher than in the control patients.

Over the following five years, the researchers observed HDGF levels in an additional 73 patients, which showed that patients with HDGF levels greater than 0.7 nanograms per milliliter had more heart problems and were limited in how far they could walk.

To combat the uncertainty around diagnosis and therapy of pulmonary arterial hypertension, Everett’s findings suggest that testing patients for high levels of HDGF can be a reliable way to gauge the severity of a patient’s pulmonary arterial hypertension condition.

“This could be a cheap and easy way to say: ‘Oh, good, your levels are going down. Let’s try to take away one of your medicines and see how that works,’” Everett said. “Or if you know from the very beginning of their treatment that someone isn’t responding to any medicines, you can get them on the list for a lung transplant much sooner.”