Expert Consensus to Explore the Definition and Characterization of Methamphetamine-Associated Pulmonary Arterial Hypertension and Key Treatment Considerations

<h3>Background</h3> Methamphetamine use can result in methamphetamine-associated pulmonary arterial hypertension (Meth-APAH). Compared with idiopathic pulmonary arterial hypertension (PAH), Meth-APAH may have a worse clinical course. <h3>Research Question</h3> To investigate the classification of methamphetamine use status and associated treatment considerations for patients with Meth-APAH. <h3>Study Design and Methods</h3> US-based experts (N = 12) who manage patients with Meth-APAH were recruited to a double-blinded, modified Delphi panel (2 survey rounds and a virtual consensus meeting). During the survey rounds, panelists answered a range of questions with free-text responses or rating statements. For rating questions, consensus was defined as ≥ 80% of panelists rating their agreement (from 7 to 9) or disagreement (from 1 to 3) using a 9-point Likert scale. <h3>Results</h3> The panel was unable to reach consensus on the definition of Meth-APAH. Although there was general agreement that Meth-APAH is a group 1 PAH diagnosis in a patient with a history of methamphetamine use, a number of panelists thought that additional details were needed (eg, duration, cumulative exposure) and these details could not be agreed on. The panel agreed that Meth-APAH is heterogeneous in disease course and physicians should explore the potential of methamphetamine use in all new and existing cases of PAH regardless of the regional prevalence of methamphetamine use. The panel achieved consensus that patients with Meth-APAH should be treated for both PAH and drug addiction. There are no Meth-APAH-specific barriers to double combination therapy (ie, endothelin receptor antagonists, phosphodiesterase 5 inhibitors), but a range of patient and disease factors may influence the choice and route of delivery for other therapies. <h3>Interpretation</h3> The characterization of Meth-APAH may help facilitate the identification, treatment, and management of patients with Meth-APAH to improve clinical outcomes.