Association Between Ursodeoxycholic Acid and Clinical Outcomes in Patients With COVID-19 Infection: Population-Based Cohort Study

Background Several studies have investigated the relationship between ursodeoxycholic acid (UDCA) and COVID-19 infection. However, complex and conflicting results have generated confusion in the application of these results. Objective We aimed to investigate whether the association between UDCA and COVID-19 infection can also be demonstrated through the analysis of a large-scale cohort. Methods This retrospective study used local and nationwide cohorts, namely, the Jeonbuk National University Hospital into the Observational Medical Outcomes Partnership common data model cohort (JBUH CDM) and the Korean National Health Insurance Service claim–based database (NHIS). We investigated UDCA intake and its relationship with COVID-19 susceptibility and severity using validated propensity score matching. Results Regarding COVID-19 susceptibility, the adjusted hazard ratio (aHR) value of the UDCA intake was significantly lowered to 0.71 in the case of the JBUH CDM (95% CI 0.52-0.98) and was significantly lowered to 0.93 (95% CI 0.90-0.96) in the case of the NHIS. Regarding COVID-19 severity, the UDCA intake was found to be significantly lowered to 0.21 (95% CI 0.09-0.46) in the case of JBUH CDM. Furthermore, the aHR value was significantly lowered to 0.77 in the case of NHIS (95% CI 0.62-0.95). Conclusions Using a large-scale local and nationwide cohort, we confirmed that UDCA intake was significantly associated with reductions in COVID-19 susceptibility and severity. These trends remained consistent regardless of the UDCA dosage. This suggests the potential of UDCA as a preventive and therapeutic agent for COVID-19 infection.