Clinical Factors Associated with Prolonged Hospitalization in Patients Undergoing ERCP: A Tertiary-Care Cohort Study

Background/Objectives: Hospital length of stay (LOS) in patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) may reflect baseline condition and underlying disease as well as procedure-related morbidity. We evaluated factors associated with prolonged hospital stay (PLOS) and the association of post-ERCP pancreatitis (PEP) with hospitalization duration. Methods: This retrospective single-center secondary analysis included 806 consecutive patients undergoing ERCP within 48 h of admission in 2019-2021. PLOS was defined as total LOS ≥ 12 days, corresponding to hospitalization above the 75th percentile. Modified Poisson regression estimated adjusted risk ratios (aRRs); LOS was also analyzed using negative binomial and median quantile regression. Sensitivity analyses used LOS > 7 and >14 days, a PLOS/death composite, and a PEP-excluded cohort. Results: Among 788 live discharges with complete LOS data, 176 (22.3%) met the PLOS criterion. In the primary Model A, emergency admission (aRR 3.01, 95% CI 2.01-4.51), cholangitis/postoperative indication (aRR 2.71, 95% CI 1.57-4.66), liver disease (aRR 1.85, 95% CI 1.10-3.12), and age (aRR 1.12 per 10 years, 95% CI 1.02-1.22) were associated with PLOS. PEP was associated with PLOS when added as a post-procedural exposure (aRR 2.34, 95% CI 1.67-3.29). Baseline associations were broadly preserved across sensitivity analyses. Conclusions: Prolonged hospitalization was associated mainly with acute clinical context, underlying disease, and patient characteristics. PEP was also associated with longer hospitalization, but this result should be interpreted cautiously because the historical PEP adjudication rule was not retained.