PAH-specific therapy: ERA most common, PDE5 inhibitors, parenteral prostanoids, 90.7% of PAH-ILD and 98.2% of PAH-only received PH-specific meds (P = 0.014), Immunosuppressants more frequent in ILD groups (e.g., MMF, cyclophosphamide, prednisolone; P < 0.001). Here, PDE5A is linked to pulmonary arterial hypertension.