The effectiveness of combining ursodeoxycholic acid with vitamin D in treating patients with primary biliary cholangitis and its impact on hepatic fibrosis: a randomized trial

To investigate the effectiveness of combining ursodeoxycholic acid (UDCA) and vitamin D (VitD) in treating patients with primary biliary cholangitis (PBC) and its impact on hepatic fibrosis. A prospective analysis was conducted on 60 treatment-naive PBC patients who were admitted to our Infectious Diseases Department and outpatient clinic from May 2021 to December 2022. All patients were taking UDCA capsules orally for one year and were randomly divided into two groups: UDCA + VitD group, which received UDCA combined with VitD (1200 IU/day) treatment, and the UDCA monotherapy group. After one year of treatment, the UDCA monotherapy group was then further stratified into two subgroups using the same method, and treatment was extended for an additional year, to further verify the role of VitD in the treatment of PBC with UDCA. Clinical manifestations, blood tests, and imaging tests were collected before and after treatment. The efficacy was evaluated using the Paris I and Barcelona standards, and the improvement of liver stiffness value was assessed according to the liver stiffness measurement (LSM) using FibroTouch. After one year of treatment, the UDCA + VitD group showed statistically significant decreases in AST, GGT, ALP, Tbil, PT, INR, IgM and LSM levels, and increases in ALB and 25(OH)D levels compared to the UDCA monotherapy group. The 25(OH)D levels had a negative correlation with LSM levels. Additionally, 80.0% of patients in the UDCA + VitD group responded according to the Paris I criteria, while 86.7% responded according to the Barcelona criteria, 50.0% of patients in the UDCA monotherapy group responded according to the Paris I criteria and 63.3% responded according to the Barcelona criteria. The response rate in the UDCA + VitD group was higher than that in the UDCA monotherapy group under both criteria. In the second year of the study after the second randomization, 86.7% of patients responded according to the Paris I criteria in the UDCA + VitD subgroup, while 93.3% responded according to the Barcelona criteria. 53.3% of patients in the UDCA monotherapy subgroup responded according to the Paris I criteria and 66.7% according to the Barcelona criteria. The UDCA + VitD subgroup had a higher Paris I response rate compared with the UDCA monotherapy subgroup. The combination of UDCA and VitD can increase the drug response rate of UDCA and improve liver function and hepatic fibrosis in PBC patients. VitD may plays an important role in the treatment of PBC.