PAH Diagnosis and Treatment Differs Among Countries, Study Shows

How people with pulmonary arterial hypertension (PAH) are diagnosed and treated depends to a notable degree on the country or region in which they live, according to a new study, which also found that a sizable number never undergo right heart catheterization to confirm their disease.

The findings, published in the article “An International Physician Survey Of Pulmonary Arterial Hypertension Management” in the journal Pulmonary Circulation, did not include an investigation of how these differences might affect patient outcomes.

Data from several registries long suggested that procedures for the diagnosis and management of PAH differed among countries.

To understand these differences, researchers asked physicians from several countries who treat PAH patients to complete a 15-minute online questionnaire, and to provide data on three to five PAH patients they most recently treated.

A total of 560 physicians — 278 in Europe (France, Germany, Italy, Spain, and the United Kingdom), 160 in the United States, 53 in Argentina, and 69 in Japan — completed the questionnaire and submitted data for 2,618 patients.

An analysis showed significant differences in the use of various PAH-specific therapies among countries, and variation in the usage of combination therapy worldwide. For instance, a greater use of phosphodiesterase 5 inhibitors was found in the United States than in either Europe and Japan, while physicians in Japan were more likely to prescribe triple or more combination therapies than were those in other regions. These differences, the researchers said, may be due to differences in the financial aspects of healthcare among countries, as these may influence the availability of approved therapies.

Although a substantial proportion of patients were experiencing considerable disability — “our study still shows that significant impairment at the time of diagnosis is a global issue,” the researchers wrote — physicians were generally satisfied with available treatments, suggesting they accept the limitations of current PAH therapies.

More “worrying,” the researchers wrote, is that across the regions studied, a large proportion of patients (around one-fifth in most regions, and as high as one-half in Argentina) did not undergo right heart catheterization (RHC) to receive a PAH diagnosis, although this procedure is considered essential in both confirming the disease and initiating treatment. Common reasons for not using this procedure ranged from certainty of diagnosis without it to its invasive nature and patient refusal.

“This lack of adherence to the guidelines seen across different countries and registries is of particular concern because the diagnosis of PAH cannot be made without determining mean pulmonary artery pressure, pulmonary capillary wedge pressure, and pulmonary vascular resistance, all of which are obtained by RHC,” they wrote.

“Although it is yet to be demonstrated whether the current guidelines affect outcomes in PAH, the presence of such differences indicates areas where education may be useful to ensure the most appropriate management of patients with PAH,” the team concluded.