Pulmonary arterial hypertension: progress and challenges in the modern treatment era.
Pulmonary arterial hypertension (PAH) is a chronic, progressive disease with an estimated incidence of 2 cases per million individuals per year and a prevalence of approximately 10 to 15 cases per million individuals. PAH is more common in certain groups of patients, such as those with connective tissue disease and congenital heart disease, and is often overlooked in patients with these comorbidities. Treatment options in the United States have expanded to include 12 PAH-specific therapies, 3 of which were approved in 2013. As a result of treatment advancements, PAH patients are living longer. However, many challenges remain. Resource utilization in PAH, a primary driver of which is hospitalization, imposes a major economic burden on patients, payers, and society. Because change in 6-minute walk distance and other historical measures do not correlate well with the risk of hospitalization, guidelines favor more rigorous composite assessments of efficacy that take into account clinical worsening, including mortality and hospitalization. Stakeholders, including providers and payers, are tasked with selecting treatments with the best evidence of clinical benefit. Managing adherence to those therapies remains an important priority in improving clinical outcomes and reducing the overall clinical and economic burden of PAH. Future research that includes patient-reported outcomes, particularly those that reflect health-related quality of life, may be of particular relevance in this complex disease.