Comparison of the clinical features of Japanese patients with primary biliary cirrhosis in 1999 and 2004: utilization of clinical data when patients applied to receive public financial aid.

Background: In Asia there are few reports considering time intervals in the examination of clinical features of primary biliary cirrhosis (PBC). Therefore, we tried to compare the characteristics of patients with PBC in two different years.

Methods: In two fiscal years (1999 and 2004), 9,761 and 13,142 patients with symptomatic PBC were registered to receive public financial aid from the Ministry of Health, Labour and Welfare of Japan, respectively. For the present study, clinical data from 2,127 patients in 1999 and 6,423 ones in 2004 were available. We compared the data in the two different years, including sex, age, major symptoms, and laboratory data.

Results: Male/female ratios were the same figure (0.13 for 1999 and 2004). The median age was significantly older in 2004 than in 1999 (59 years for 1999, 63 years for 2004, respectively, p<0.01). Jaundice and esophageal varices were found significantly less frequent in 2004 than in 1999 (p<0.01 for each item). Levels of total bilirubin,gamma-glutamyl transpeptidase (gamma-GTP), total cholesterol, and immunoglobulin M were significantly lower in 2004 than in 1999 (p< 0.02 for total bilirubin, and p<0.01 for other each item). The positive rate of antimitochondrial antibodies was significantly higher in 1999 than in 2004 (87.0% for 1999, 83.5% for 2004, respectively, p<0.01)). Complicated autoimmune diseases such as Sjögren's syndrome, rheumatoid arthritis, and chronic thyroiditis were found significantly more frequent in 2004 than in 1999 (p<0.01 for each item).

Conclusions: Among the patients with PBC in 2004, an increase in median age, and lower levels of laboratory data such as gamma-GTP have been found compared to 1999. These results may show an accumulation of patients with better prognosis and the recent medical progress in controlling patients with PBC.J Epidemiol 2007; 17: 210-214.