Study Population

The Brazilian Cholestasis Study Group (BCSG) is a multicenter collaborative consortium of investigators from academic institutions and community-based sites that treat patients with PBC in Brazil. The study population included adult (aged ≥18 years) patients diagnosed with PBC between January 1st 1992 and December 31st^, 2019 in 28 hepatology centers across the country. All study procedures were conducted in accordance with the ethical standards of the Helsinki Declaration. The present study was approved by the Federal University of Minas Gerais Ethics Committee Board (CAAE 98627218.6.1001.5149), and individual informed consent was waived as this study was retrospective in design. Diagnosis of PBC was considered if patients fulfilled at least two of the following three diagnostic criteria for PBC as recommended by the American Association for the Study of Liver Diseases guidelines: 1) positive serology for anti-mitochondrial antibodies (AMA) or PBC-specific antinuclear antibodies (ANA); 2) persistent increase in the serum alkaline phosphatase (ALP) level; and 3) liver histology compatible with PBC (Lindor et al., 2019). Patients in whom the diagnosis could not be confirmed or who had another etiology of liver disease were excluded.