Methamphetamine-Associated Pulmonary Arterial Hypertension: Impact, Mechanisms, and a Framework for Management.

Methamphetamine-associated pulmonary arterial hypertension (Meth-PAH) is an increasingly prevalent but understudied subtype of Group 1 pulmonary arterial hypertension (PAH). While most prevalent in the Western United States, its reach continues to expand with the evolving global methamphetamine epidemic. Despite its designation as a definite cause of PAH, there are no standardized diagnostic criteria or treatment guidelines specific to Meth-PAH. This review summarizes its epidemiology, proposed pathophysiology, clinical management, and treatment challenges. We outline a pragmatic approach to Meth-PAH, emphasizing structured screening for substance use, initiation of oral PAH-specific therapies regardless of abstinence, and therapy escalation based on adherence and serial risk assessment. Key knowledge gaps include Meth-PAH pathophysiology, performance of risk stratification tools, and the safety and efficacy of PAH therapies in patients with ongoing use. A multidisciplinary approach is needed to address both Meth-PAH and methamphetamine use disorder to improve outcomes in this high-risk, stigmatized population.