Abstract
Pulmonary hypertension is a complex and irreversible pulmonary vascular disease with a significant impact on patients' lives. Pulmonary hypertension is categorized into five groups according to its etiology. Frailty is a multifaceted disorder that leads to physical, social, cognitive, and psychological decline. Several studies have linked a high occurrence of frailty to heart failure and chronic lung diseases, but the prevalence and impact of frailty in pulmonary arterial hypertension (PAH) remain largely unexplored. At the molecular level, inflammation, oxidative stress, cellular senescence, and mitochondrial dysfunction play pivotal roles in the pathophysiology of frailty in pulmonary hypertension. Dysfunction of cardiac, respiratory, and skeletal muscles results in exercise intolerance, which promotes deconditioning and frailty. Exercise training in PAH, heart failure, and chronic lung disease has shown promise in improving quality of life, exertion tolerance, and frailty scores. Properly designed studies are needed to elucidate the predictive value of frailty and to identify assessment and treatment tools in pulmonary hypertension, particularly PAH, to aid clinicians in individualizing care plans and improving patient outcomes. In this narrative review, we describe the pathobiology of frailty in pulmonary hypertension, assessment tools, the impact of frailty on different pulmonary hypertension groups, and suggestions for potential interventions.