Clinical Characteristics and Long-Term Prognosis of Primary Biliary Cholangitis in Japan: Results of the 2nd-Generation Nationwide Survey.

Aim: The Japan Primary Biliary Cholangitis Study Group (JPBCSG) has conducted nationwide surveys of primary biliary cholangitis (PBC) since 1980. Due to the progress in the management of PBC, a more comprehensive survey platform is desired.

Methods: The JPBCSG conducted the 17th survey of PBC by using an electronic data capture (EDC) system: The patients' clinical demography at diagnosis and the outcomes of newly and past registered cases (till the 16th) were entered jointly in the EDC system. A questionnaire for treatment response was included in the survey. Using the new platform, the trends in clinical demography and the long-term prognosis of PBC were analyzed.

Results: The percentage of male patients with PBC showed a significant increase from the period before the end of 2010 [Period 1, 12.4% (n = 772)] to the period after 2021 [Period 4, 20.6% (n = 345), p < 0.001] (n = 2579, in total). The mean age at diagnosis also rose significantly from 56.8 years old in Period 1 to 61.8 years in Period 4 (p < 0.001). There were no significant changes in the prevalence of symptoms at diagnosis. In a multivariate Cox-regression analysis, older age (hazard ratio [HR] 3.48, p = 0.001), female sex (HR 0.46, p = 0.046), total bilirubin (HR 3.84, p = 0.009), fluid retention (HR 5.69, p < 0.001), and esophagogastric varices (HR 2.66, p = 0.015) were significantly associated with liver-related mortality and liver transplantation.

Conclusion: We have established the 2nd-generation nationwide survey of PBC in Japan. The survey results revealed not only demographical trends in Japanese patients with PBC but also risk factors for their prognosis.