Patients with the history of TIA had more pronounced decrease in PON activity (−31.85; −114.05 to −12.55; median; interquartile range; P = 0.035) than those without stroke history or with ischemic stroke history (10.90; −23.40 to 10.00 and −8.30; −17.15 to 2.72, resp). Here, PON1 is linked to transient ischemic attack.