IL17A and pulmonary arterial hypertension: Utilizing logistic regression with the LASSO regularization, the following 11 clinical or laboratory factors remained statistically significant in the training cohort: age, MYOACT score, hypertension, pharyngeal muscle involvement, pulmonary hypertension, fungal infection, AMAs, LDH, IL-6, IL-17A, anti-MDA5 antibody (Fig. 2A and 2B).