Furthermore, those with a history of a DU were more likely to be treated with vasodilator therapies such as calcium channel blockers (CCB) and iloprost than those without DUs in addition to certain endothelial receptor antagonists (ERAs) and phosphodiesterase-5 inhibitors (PDE5) which were prescribed as a PAH specific therapy in those with PAH. The gene discussed is PDE5A; the disease is pulmonary arterial hypertension.