ENPP2 and Cirrhosis: Likewise, in the PSC group, ATX activity was associated with disease duration (r = 0.204, P = 0.03; Fig. 2C) and was significantly higher in cirrhotic patients than in subjects without cirrhosis (9.3 ± 3.8 vs. 6.6 ± 3.0 nmol mL−1 min−1, P < 0.001; Fig. 2D).