Identification of the risk factors for liver-related mortality in primary biliary cirrhosis patients: a case-control study in China

Background: Primary biliary cirrhosis (PBC) is an autoimmune liver condition with relatively slow progression, leading to liver failure and death. We retrospectively investigated potential risk factors of liver-related mortality in patients with PBC. Methods: The data of patients with PBC at the First Affiliated Hospital of Zhengzhou University in China from 2007 to 2013 were included, specifically that of 91 deceased and 364 living (control) patients. Univariate and multivariate conditional logistic regression models were applied to determine potential risk factors of liver-related mortality, with calculations of odds ratios (ORs) and 95% confidence intervals (CIs). Results: The following features were statistically similar between the deceased and living patients: age, gender, nationality, the status of anti-human immunodeficiency virus antibody, anti-hepatitis C virus antibody, and hepatitis B surface antigen. A large proportion of deceased PBC patients (92.31%) had died of decompensated cirrhosis; the most common immediate cause was hemorrhagic shock (41.75%), then hepatic encephalopathy (38.45%). Independent risk factors for liver-related mortality were: hepatocellular carcinoma, elevated total bilirubin (TBIL), decreased albumin (ALB) and platelet levels, and non-response to ursodeoxycholic acid (P<0.001, all). Cutoff values of TBIL and ALB for prediction of poor prognosis were determined as 38.65 μmol/L and 34.8 g/L, respectively; the areas under the ROC curve were 0.771 and 0.758 (P<0.001), respectively. Conclusions: PBC patients with hepatocellular carcinoma, high total bilirubin, low albumin or platelet levels at the initial diagnosis of disease, or who do not response to UDCA, are prone to liver-related death.