Unchanged mortality in patients with acute cholangitis despite an increase in malignant etiologies - a 25-year epidemiological study.

Background and aims: Acute cholangitis (AC) is a rare but serious condition, with an incidence of 7.0 per 10,000 people and mortality rates up to 10%. The aim of this study was to describe changes in obstruction etiology, comorbidities, clinical factors, and mortality among AC patients during a 25-year period. Methods: Using a database of 11,563 consecutive ERCP-procedures performed from 1990-2015 at Odense University Hospital, we identified all AC cases during that period. Clinical and epidemiological data were collected from the database and the Danish Patient Registry. Association with 30-day mortality was investigated using multiple logistic regression analysis with adjustment for confounding factors. Results: In total, 775 consecutive and individual cases of AC were included. Among cases, 42% (n = 326) were of malignant etiology, with an increasing incidence over time (regression coefficient [95% CI]: 0.03 [0.01-0.04] per year; p = .01). Mean Charlson Comorbidity Index was 1.4, with an increase over time (regression coefficient [95% CI]: 0.04 [0.03-0.05] per year; p < .01). Malignant obstruction etiology was associated with 30-day mortality (OR [95% CI]: 1.11 [1.04-1.18]; p < .01). Overall 30-day mortality was 12% (n = 91). After adjustment for confounding factors, no significant changes in 30-day mortality were observed over time (OR [95% CI]: 1 [1-1.00]; p = .91 per year). Conclusion: Significant increases in the incidence of malignant obstruction etiology and severity of comorbidities among AC patients were observed during the study period. Despite those findings, 30-day mortality remained unchanged, potentially reflecting a general improvement in the management of AC.