More research needed
In a related editorial, James R. Klinger, MD, a pulmonologist with Brown University, Providence, R.I., and the director of the Rhode Island Hospital Pulmonary Hypertension Center in East Providence, said there is a “keen interest” in treating PH in COPD despite a lack of consistency on whether treatment is effective in this patient population. About 80% of PH centers in the United States treat PH in COPD when they treat conditions like lung disease with PAH medication, he pointed out. However, he questioned whether current medications designed for PAH could improve pulmonary hemodynamics for PH in COPD.
“Reasons that the pathobiologic condition of PH-COPD may differ from PAH include the likely exposure of the pulmonary circulation to greater degrees of hypoxia and hypercapnia and the greater loss of alveolar capillaries associated with emphysema,” he said.
The study by Dr. Dario Vizza and colleagues is an attempt to evaluate treatment response for patients with PH and COPD “in a way that allows comparison with patients who have been treated with similar drugs for PAH,” Dr. Klinger said. He noted the study’s retrospective nature, lack of control group, and lack of information on lung disease severity could limit the findings.
“These limitations preclude recommendations for the routine treatment of patients with PH-COPD, but the findings suggest that, despite greater morbidity at baseline, patients with PH-COPD may be nearly as likely to benefit from PAH medications as patients with IPAH,” he said.
“What is needed now is well-designed randomized controlled studies to determine whether improved outcomes can be achieved in this population and which patients are most likely to benefit,” he concluded. “Simply put: How bad does PH need to be in patients with COPD before treatment is helpful, and how severe does COPD need to be before PH treatment is futile?”
The authors reported personal and institutional relationships in the form of grants, consultancies, advisory board memberships, speakers bureau appointments, honoraria, patents, grant and research funding, lectures, travel compensation, and steering committee positions for a variety of pharmaceutical companies, agencies, societies, journals, medical publishing companies, and other organizations. Dr. Klinger reported his institution receives grant support from Acceleron and United Therapeutics in the area of PH, and he has been an unpaid consultant for Bayer.