Ursodeoxycholic acid (UDCA) has an established effect on liver biochemistries in primary biliary cirrhosis (PBC). Few studies have evaluated long-term laboratory treatment effects and data beyond 6 years are not available. The aim of this study was to assess the long-term evolution of liver biochemistries during prolonged treatment with UDCA in biochemically non-advanced PBC.

Prospective multicenter cohort study of patients with PBC with pretreatment normal bilirubin and albumin, treated with UDCA 13–15mg/kg/day. At yearly intervals, follow-up data including serum bilirubin, alkaline phosphatase (ALP), transaminases, albumin and IgM were collected. Data were analyzed with a repeated measurement model.

Two hundred and twenty-five patients were included and followed during a median period of 10.3 years. Following 1-year treatment with UDCA 36–100% of the total biochemical improvement was achieved, the maximum response was observed after 3 years. After initial improvements, bilirubin and AST levels increased and albumin levels significantly decreased after 6–10 years. However, these changes were of limited magnitude. The beneficial effects on ALT and ALP were maintained while IgM continued to decrease.

In non-advanced PBC the biochemical response to UDCA is maintained up to 15 years. The long-term evolution of bilirubin, albumin and ALT differs from that of ALP and AST. The mean IgM level normalised and levels continued to decrease during the period of follow-up.