A Study of Real-world Cohort of Pulmonary Arterial Hypertension (PAH) Participants

This study is designed to describe pulmonary arterial hypertension (PAH) participants in terms of their clinical characteristics, therapies used, disease progression, and outcomes (example, death, hospitalization, risk category for predicted mortality risk, and patient-reported outcomes \[PROs\]) in real-world clinical practice. This study will collect high-quality real-world data that may be used as a stand-alone dataset or in combination with other studies to address relevant research questions (example, serve as an external control dataset to another study) to support development and access to PAH therapies, as well as to contribute to the knowledge base of PAH through publications.


Eligibility Criteria:
Inclusion Criteria:

* Symptomatic pulmonary arterial hypertension (PAH) in any PAH subtype
* PAH diagnosis confirmed by hemodynamic evaluation at rest at any time prior to or at the index date fulfilling all of the criteria below: a) Mean pulmonary artery pressure greater than (\>) 20 millimeters of mercury (mm Hg), and b) Pulmonary artery wedge pressure or left ventricular end diastolic pressure less than or equal to (\<=) 15 mm Hg, and c) Pulmonary vascular resistance greater than or equal to (\>=) 3 Wood Units (that is, \>= 240 dynes seconds per centimeters penta \[dyn∙sec/cm\^5\])
* Participant satisfies either a or b: a) Newly initiating 1 or more PAH therapy(ies) (as monotherapy or add-on therapy) at index date. These newly initiated PAH therapies should not have been used within 3 months of the index date; b) Taking macitentan 10 milligrams (mg) therapy (as monotherapy or in combination) with no changes in PAH therapy for within 3 months prior to the index date
* All mandated assessments must be performed and recorded at the baseline visit before the initiation of the new PAH therapy at the index date or enrollment in the study.
* For the pulmonary arterial hypertension-symptoms and impact (PAH-SYMPACT) substudy only: Participants initiating any endothelin receptor antagonist (ERA) or phosphodiesterase-5 inhibitor therapies at index date or at therapy change must provide consent to enroll in the optional PAH-SYMPACT substudy. Refusal to give consent for the optional PAH-SYMPACT substudy will not exclude a participant from participation in the main study

Exclusion Criteria:

* Participants enrolled in any interventional clinical trial with an investigational therapy in the 3-month period prior to index date
* Currently enrolled in an observational study sponsored or managed by a Janssen company
* Presence of moderate or severe obstructive lung disease (forced expiratory volume in 1 second \[FEV1\] / forced vital capacity \[FVC\] \<70%; and FEV1 \<60% of predicted after bronchodilator administration) in participants with a known or suspected history of significant lung disease, as documented by a spirometry test performed within 1 year prior to screening
* Presence of moderate or severe restrictive lung disease (for example, total lung capacity or FVC \<60 percent \[%\] of normal predicted value) in participants with a known or suspected history of significant lung disease, as documented by a spirometry test performed within 1 year prior to screening