Characteristics and Outcomes of Methamphetamine-Associated Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) associated with the use of methamphetamine is a severe, progressive form of the disease that is characterized by poor outcomes and worse prognosis than idiopathic PAH (iPAH), according to a recent prospective cohort study published in the American Journal of Respiratory and Critical Care Medicine.

According to the researchers, this study is the first of its kind to describe the presentation, clinical phenotype, histopathology, and long-term outcomes of patients with methamphetamine-associated PAH compared with patients with iPAH.

A total of 90 patients with methamphetamine-associated PAH and 97 patients with iPAH who presented to the Stanford University Pulmonary Hypertension Program in California between 2003 and 2015 were enrolled in the study. Clinical, pulmonary angiography, histopathology, and outcomes data were compared between the 2 groups. The investigators used data from the Healthcare Cost and Utilization Project to assess the epidemiology of PAH among methamphetamine users who were hospitalized in the state of California.

Patients with methamphetamine-associated PAH were less likely to be women. Age, body mass index, and 6-minute walk test distance were similar in the methamphetamine-associated PAH and iPAH groups. However, participants in the methamphetamine-associated PAH arm reported more advanced symptoms of heart failure, had significantly higher right arterial pressure (12.7±6.8 mm Hg) than those with iPAH (9.8±5.1 mm Hg; P =.001), and had lower stroke volume index (22.2±7.1 mL/m² vs 25.5±8.7 mL/m², respectively; P =.01).

Event-free survival in patients with methamphetamine-associated PAH was 64.2%, 47.2%, and 25% at 2.5, 5, and 10 years, respectively, which represented more than double the risk for clinical worsening or death compared with patients with iPAH (hazard ratio, 2.04; 95% CI, 1.28-3.25; P =.003) independent of cofounders. Based on California data, there was a 2.6-fold increase in the risk for a PAH diagnosis in hospitalized methamphetamine users.

The investigators noted that methamphetamine-associated PAH exhibits hemodynamic and histopathologic features of precapillary pulmonary vascular disease. Based on the findings of this study, the need exists for future studies of methamphetamine-associated PAH that focus on the mechanisms of disease and potential treatment considerations.

Reference

Zamanian RT, Hedlin H, Greuenwald P, et al. Features and outcomes of methamphetamine associated pulmonary arterial hypertension [published online September 21, 2017]. Am J Respir Crit Care Med.