Abstract
BACKGROUND: The safety of morphine in acute pancreatitis (AP) remains controversial due to theoretical risks of exacerbating complications. This study evaluated whether early morphine use correlates with clinical deterioration in AP. METHODS: In this retrospective cohort study, 154 patients with AP (diagnosed per Revised Atlanta Criteria) treated at a tertiary center (2012-2024) were stratified by morphine use within 48 h of admission. The primary outcome was a composite of clinical deterioration (30-day mortality, mechanical ventilation, vasopressor use, surgery, prolonged hospitalization, CRP doubling, or new organ failure). Associations were assessed using multivariable logistic regression adjusted for age, sex, admission severity, and inflammatory markers. RESULTS: Of 154 patients, 53 received early morphine. Baseline age and sex distributions were similar between groups, but morphine recipients had lower mechanical ventilation rates (17.0% vs. 35.6%, p = 0.02) and higher hemoglobin (131.0 vs. 122.0 g/L, p = 0.01). Clinical deterioration occurred in 49.1% (morphine) vs. 62.4% (non-morphine), with no significant difference (adjusted OR = 0.61, 95% CI: 0.29-1.28, p = 0.19). High-dose opioids (MME ≥ 100, n = 24) showed no association with deterioration (adjusted OR = 0.92, 95% CI: 0.33-2.54, p = 0.87). Severity-adjusted analyses confirmed these findings. CONCLUSIONS: In this cohort, early morphine and opioid use were not associated with clinical deterioration in acute pancreatitis. These findings support the safety of early opioid analgesia for pain control in AP, although residual confounding cannot be excluded. Prospective studies are needed to confirm causality and inform guideline recommendations.