PAH in the era of obesity: navigating phenotypes of pulmonary hypertension

INTRODUCTION: Pulmonary arterial hypertension (PAH) is a progressive vasculopathy whose phenotype has shifted over the decades from young women to older patients with cardiometabolic comorbidities. Obesity is among the most prevalent and clinically consequential of these comorbidities, affecting 24-40% of patients in contemporary PAH registries. AREAS COVERED: We review the epidemiology of obesity and its impact on PAH; the definition of obesity and the limitations of body mass index; the effects of obesity on adipose, cardiovascular and respiratory systems; its association with health disparities; the clinical approach to the patient with obesity and suspected pulmonary hypertension (PH), including right heart catheterization with provocative maneuvers and esophageal manometry; comorbid conditions and the obesity paradox; and management, including weight loss, PAH-specific therapy, heart failure with preserved ejection fraction and sleep-disordered breathing. A literature search of PubMed/MEDLINE was performed for articles published from database inception to September 2026. EXPERT OPINION: Obesity has implications in the origin, symptoms, diagnosis and management of PH. Accurate characterization of PH in obese patients depends first on measuring and reporting pressures that reflect true transmural hemodynamics. Incretin-based therapy and activin signaling inhibition are promising therapeutic directions, but dedicated trials in patients with obesity and pulmonary hypertension are needed.