CONGRESS ABSTRACT

Background. The use and effectiveness of parenteral prostanoids in older patients with pulmonary arterial hypertension (PAH) are unknown. We investigated the association of paretenteral prostanoids use with mortality in elderly PAH patients. Methods. PAH patients aged ≥65 years enrolled in the FOCUS-PAH registry between 2001 and 2023 were included. One and five-year mortality was investigated. A positive control analysis in patients <65 years was performed. Results. Among 658 patients with available follow-up evaluation, 213 (32%) were ≥65 years old and 8% (n=17) were treated with parenteral prostanoids. Treated patients had features of more severe disease but similar distribution of comorbidities. Five-year overall survival was 0% and 49% in patients with and without parenteral prostanoids, respectively. Crude 5-year all-cause mortality risk was significantly higher in patients treated with parenteral prostanoids. After adjustment for sex, age, year of diagnosis, and ESC/ERS 4-strata risk category, the patients on parenteral prostanoids had an all-cause mortality risk that was >2-fold higher at 5 years (HR 2.30, 95%CI 1.21-4.38, p=0.011) and >3-fold higher at 1 year (HR 3.79, 95%CI 1.60-8.95, p=0.002) compared with patients not treated with parenteral prostanoids. In patients <65 years old, use of parenteral prostanoids was associated with a non-significant lower risk of all-cause mortality. Conclusions. At first follow-up, 8% of PAH patients ≥65 years, were treated with parenteral prostanoids. Use of prostanoids in these patients was associated with higher risk of one- and five-year all-cause mortality. These findings emphasize the importance of improving patient selection for prostanoid treatment and underscore the need for randomized controlled studies specifically targeting elderly patients.