SIRT3 and pulmonary arterial hypertension: No significant difference in SIRT3 levels was detected between SSc patients with PAH (median 0.74 ng/mL, IQR 0.20–0.86 ng/mL) and those without PAH (median 0.35 ng/mL, IQR 0.22–0.62 ng/mL; p > 0.05).