Abstract 4119891: Risk Factors of Anemia in Pulmonary Arterial Hypertension Patients with Endothelin Receptor Antagonists Administration and Related Treatment

Background: Endothelin receptor antagonists (ERAs) demonstrated significant efficiency in delaying clinical deterioration and improving survival of patients with pulmonary arterial hypertension (PAH). However, the frequent occurrence of anemia after ERAs administration has gained clinical attention currently, whereas the etiology of anemia is unclear. The risk factors of ERAs associated anemia remained undefined. Therefore, we aim to investigate risk factors of developing anemia after ERAs treatment and whether iron supplement could correct anemia. Method: A retrospective cohort study was performed among patients with PAH who received ERAs between January, 2017 and December, 2019 in Fuwai hospital. The primary outcome was development of anemia after ERAs therapy and secondary outcome was correction of anemia after iron supplement. Results: A total of 120 patients with PAH were included in the study and 28 patients developed anemia during follow up . Distinctively, all the patients who developed anemia were female. After ERAs administration, iron metabolism (Ferritin 95.29±144.79 μg/L versus 69.9±118.25 μg/L, P <0.001) and hemoglobin (154.21±23.80 g/L versus 136.12±28.61 g/L, P <0.001) reduced significantly in the total cohort with patients who developed anemia more significant. Baseline iron metabolism (Ferritin: HR 0.98, 95%CI 0.96-0.99, P =0.02) was independently associated with development of anemia after ERAs administration. Compared with patients with iron replete, patients with iron deficiency had over 9-fold risk of developing anemia after receiving ERAs (HR = 9.59, 95%CI 3.62-25.41, P < 0.01). Iron supplement could effectively correct anemia. Conclusion: It is advised that patients receiving ERAs monitor iron metabolism and hemoglobin regularly, especially females and those with low hemoglobin level and compromised iron homeostasis before ERAs administration, which facilitates prevention and early detection of anemia. ERAs-related anemia is mostly mild, oral iron supplement could effectively reverse anemia and aberrant iron metabolism.