In order to analyze the factors contributing to the elevated serum ATX level, we performed a binary logistic regression analysis of the association of serum ATX level (low or high based on a cutoff value of 36.96 ng/mL) with the severity of lung injury (based on a PaO2/FIO2 ratio > 200 mmHg or ≤ 200 mmHg), multiorgan damage (with or without liver, renal, cardiovascular, nervous system, or coagulation injury), and the etiology of ARDS (direct or indirect injury). Here, ENPP2 is linked to acute respiratory distress syndrome.