SERPINE1 and hypothyroidism: Chadarevian et al. studied the fibrinolytic system in hypothyroid patients and documented a different fibrinolytic pattern according to the severity of hypothyroidism: an increased fibrinolytic activity (i.e., low levels of a2- antiplasmin, tissue plasminogen activator (tPA) and plasminogen activator inhibitor (PAI-1), and high Ddimer levels) was observed in overt hypothyroidism, whereas a decreased fibrinolytic activity (high levels of a2-antiplasmin, tPA and PAI-1, and low D-dimer levels) was found in subclinical hypothyroidism [20].