Long-term prognosis of primary biliary cirrhosis (PBC) in Japan and analysis of the factors of stage progression in asymptomatic PBC (a-PBC)

Abstract

Objective: Based on data from a national survey of primary biliary cirrhosis (PBC), the pathology and prognosis of PBC in Japan were clarified. In particular, we tried to perform multivariate analysis of factors useful in determining prognosis of asymptomatic PBC (a-PBC). Methods: The survey was performed 10 times. Responses from 3778 of 4361 registered patients (416 institutions) were investigated (survey period: January 1968–December 1998). At the time of diagnosis, patients were classified as a-PBC or symptomatic PBC (s1-PBC; pruritus only, s2-PBC; jaundice and serum bilirubin level above 2 mg/dl). The survival rate was obtained by the Kaplan–Meier method. Logistic regression analysis was used in multivariate analysis of prognostic factors of a-PBC. Results: There were no significant differences in clinical findings from those in previous reports. The 5-year survival rates of patients with a-PBC, s1-PBC, and s2-PBC at the time of diagnosis were 97, 88, and 53%, respectively. Patients with a-PBC at the time of diagnosis were divided into groups: those in whom the disease progressed to s2-PBC (8%) and did not progress to s2-PBC (92%) at the final examination, and the prognosis was compared between groups. The prognosis was significantly poorer in the s2-PBC progression group. As a result of multivariate analysis for prediction of prognosis, levels at diagnosis of total serum bilirubin (T-Bil), albumin (Alb), total cholesterol (T-Cho), histological stage, and presence or absence of ursodeoxycholic acid (UDCA) administration were selected as significant factors ( P<0.00001). Conclusion: Serum T-Bil, Alb, T-Cho, and histological stage at the time of diagnosis and presence or absence of UDCA administration were considered useful early prognostic indicators in patients diagnosed as having a-PBC whose prognosis may deteriorate with progression to s2-PBC.