Background: There have not been many reports regarding primary biliary cirrhosis (PBC) in Asia. We conducted a cross-sectional study of PBC in Japan.
Methods: In fiscal year 1999, 9,761 patients with symptomatic PBC were registered to receive public financial aid from the Ministry of Health, Labour and Welfare of Japan. For our cross-sectional study we chose 5,805 patients whose clinical data had been written between 1999 and 2000, and statistically analyzed the data, including sex, age, major symptoms, and laboratory data.
Results: Our study estimated that the male-to-female ratio was 1:8.0. The median ages of male and female patients were 59 and 60 years, respectively. The major symptoms and physical findings were as follows: pruritus 53.3%, jaundice 11.3%, xanthomas 5.8%, splenomegaly 38.1%, and esophageal varices 19.1%. Antimitochondrial antibody (AMA) was positive in 86.6%, but its positive rate was lower among Japanese patients than among those in western countries. IgM levels were higher among AMA-positive patients than among AMA-negative patients. Regarding Sjogren's syndrome, rheumatoid arthritis, chronic thyroiditis, and scleroderma, patients had lower frequencies of complicated autoimmune diseases than those in western countries.
Conclusions: The male-to-female ratio, frequencies by age group, symptoms and physical findings among patients with PBC were consistent with previous reports in Japan and from other countries. However, positivity of AMA and the frequency of complicated autoimmune diseases were lower among patients in Japan than among those in western countries.