S55 Comprehensive Mortality Trends in Primary Bile Cholangitis: A Dual Analysis of Underlying and Multiple Cause Deaths and Age-Adjusted Rates (1999 to 2020)

Introduction: Primary Biliary Cholangitis (PBC) is a chronic autoimmune liver disease that may contribute to mortality as both an underlying and contributing (multiple) cause of death. Understanding trends in mortality related to PBC provides insight into disease burden and informs healthcare policy and management strategies. Methods: Data on PBC-related deaths were extracted from CDC WONDER for the years 1999 to 2020. Two categories were analyzed: deaths in which PBC was the underlying cause and those in which it was listed as a multiple cause of death. Trends in absolute number of deaths and age-adjusted mortality rates (AAMR) were assessed. Results: Throughout the study period, deaths due to multiple causes involving PBC consistently exceeded those where PBC was the underlying cause. While the total number of deaths in both categories remained relatively stable with minor fluctuations, there was a notable decline in both absolute deaths and AAMRs after 2018. The AAMR for PBC as an underlying cause declined from approximately 0.20 per 100,000 in 1999 to around 0.12 in 2020. Similarly, the AAMR for PBC as a multiple cause decreased slightly but remained higher than for underlying cause deaths across all years. Conclusion: The burden of mortality involving PBC has declined modestly over the last 2 decades, particularly in age-adjusted terms. However, PBC continues to contribute to a significant number of deaths annually, especially when considering it as a multiple cause of death. These findings highlight the need for continued surveillance and targeted interventions to further reduce PBC-related mortality.