For the same timepoints, an exploratory model built including only the baseline presence of ILD, baseline presence of PAH, mRSS, and age showed an AUC ± SE of 0.723 ± 0.036, 0.716 ± 0.034, and 0.716 ± 0.033, respectively, and a C‐index ± SE of 0.713 ± 0.040, whereas a model built with IFN score alone had an AUC ± SE of 0.728 ± 0.032, 0.730 ± 0.032, and 0.730 ± 0.032, respectively, with a C‐index ± SE of 0.733 ± 0.032 (Supplementary Figure 1). This evidence concerns the gene IFNA1 and pulmonary arterial hypertension.