Treatment Response and Survival in Methamphetamine-Associated Pulmonary Arterial Hypertension

Methamphetamine-associated pulmonary arterial hypertension (Meth-PAH) represents a growing subset of PAH. Relative to idiopathic PAH (iPAH), it is unknown whether patients with Meth-PAH treated with continuous prostacyclin have similar outcomes and treatment response. The aims of this analysis are to evaluate survival, response to therapy, and right ventricle function in similarly treated patients with Meth-PAH and iPAH.

A prospective protocolized cohort of 138 incident patients (64 Meth-PAH, 74 iPAH) was followed longitudinally, with all patients being treatment-naïve at baseline. Hemodynamic assessments, cardiac imaging, and response to therapy were evaluated. A standardized therapeutic approach involving parenteral subcutaneous treprostinil was applied. Survival was analyzed using Kaplan-Meier and Cox regression.

Both groups had similarly advanced PAH at presentation. Improvement in hemodynamics and reduction in European Respiratory Society risk scores were seen over the course of follow-up in both groups. Twenty-nine of 64 (45%) Meth-PAH and 51/74 (69%) of iPAH were initiated on parenteral prostacyclin. During treatment, only 4 patients (2 iPAH and 2 meth-PAH) were taken off treprostinil because of safety concerns. Transplant-free survival was 54/64 (84.4%) for meth-PAH over a mean follow-up time of 46 months and 54/74 (72.9%) for iPAH over a mean follow-up time of 67 months. Additionally, continued methamphetamine use did not adversely affect disease progression or mortality.

Among Meth-PAH patients treated with an aggressive parenteral prostacyclin strategy, there is not a large difference in mortality and treatment response to iPAH. Further research is warranted to explore the long-term effects of methamphetamine use on PAH pathogenesis and outcomes.