Prognosis of Pulmonary Arterial Hypertension

Abstract

Listen

Translate article

The study of rare diseases is limited by just that, their infrequency. Pulmonary arterial hypertension (PAH), for example, has a prevalence of 15 cases per million.1 Although there has been an explosion in knowledge of and therapies for this life-threatening disease over the past decade, most of our insight is based on small studies. The first therapy that was approved by the Food and Drug Administration in 1995, intravenous epoprostenol, was based on the results of an 81-patient trial.2 The most recently approved therapy, inhaled treprostinil, in 2009, was based on the results of a 235-patient trial.3 Similarly, our understanding of the natural history of this disease is based on small observational series. Articles see pp 156 and 164 To further our comprehension of rare diseases, we often turn to “registries,” constructed as multicenter cohorts of patients who have the disease with longitudinal follow-up. Despite the inherent limitations of their observational and uncontrolled nature, which also represent strengths, these cohorts are useful to describe and compare patient characteristics, practice patterns, and outcomes. Observations from such registries can generate hypotheses that subsequently form the basis of further studies. Lastly, such cohorts facilitate the study of the prognostic profile of the disease via the derivation and validation of clinical prediction tools. In this issue of Circulation , data from the 2 of the most important present-day registries in PAH give us the opportunity to better understand the prognosis of PAH, its determinants, and outcomes in the current treatment era. Humbert and colleagues4 share data from the French National Registry, in which 354 consecutive idiopathic, heritable, and anorexigen-associated patients with PAH were enrolled from October 2002 to October 2003. They report 1-, 2-, and 3-year survival rates of 82.9%, 67.1%, and 58.2%, respectively. Sadly, despite the many advances in …