Clinical features of sarcoidosis-associated pulmonary hypertension are similar across patients in the U.S., Europe and Middle East, but treatment is more likely to be given to patients outside the United States, a study reports.
These findings were drawn from data on 176 sarcoidosis-associated pulmonary hypertension (SAPH) patients enrolled in a multi-national, observational registry, including 94 with moderate-to-severe PH. Two-thirds lived in the U.S., and the remaining 50 across Europe or the Middle East.
The study, “Clinical features of sarcoidosis associated pulmonary hypertension: Results from a multi-national registry,” was published in the journal Respiratory Medicine.
Different studies report that pulmonary hypertension — a severe and life-limiting disease — is found in over half of the sarcoidosis patients listed for lung transplant or reporting persistent shortness of breath. Overall, its prevalence is estimated to range from 5% to 20% of all sarcoidosis cases.
A University of Cincinnati-sponsored registry known as ReSAPH (NCT01467791) collected information on SAPH patients, including their demographics, clinical course, progression, and disease management, between 2011 and 2017.
Patient data included results of pulmonary function testing, hemodynamic measures to characterize PH severity, chest imaging, exercise capacity (assessed through the six-minute walk distance test, 6MWD), and treatments given.
Clinical features of the enrolled SAPH patients were compared to sarcoidosis patients without PH in terms of demographics, disease progression, and management — with analysis finding disease similarities across those with pulmonary hypertension treated at centers in the U.S., Europe and Middle East.
Results also showed a “significant” correlation between disease severity and a reduced carbon monoxide diffusion capacity — a test used to measure the lungs’ ability to move oxygen into the bloodstream. But no link was seen between scores in spirometric tests (measuring lung function by how much and how quickly air can be exhaled) and PH severity.
Differences were found in the number of people being treated by home region or country.
At time of registry entry, the Cincinnati researchers wrote, “nearly a third” of the 126 U.S.-based patients were under no treatment, compared to “only four” in Europe or the Mideast, or 70% of patients in the U.S. compared to 84% elsewhere.
U.S. patients were also “more likely to be on current therapy with a calcium channel blocker than the non-US sites, but only seven were receiving a calcium channel blocker as monotherapy,” the study noted.
The registry did not note reasons for the lower treatment numbers in the U.S., but its researchers speculated they might be related to insurance coverage, or to more active “efforts” by the “few specialized” non-U.S. centers that agreed to participate in the registry.
Investigators concluded that they hoped the “registry will also foster a greater awareness of SAPH and encourage future randomized clinical trials to help define the role of therapy for this emerging entity.”