Objective:

To investigate the association between NLR and ALI in acute pancreatitis and evaluate its predictive value.

Approach:

• Study Design: Retrospective analysis of clinical data from 581 acute pancreatitis inpatients between 2021 and 2025.
• Statistical Methods: Utilized multivariate logistic regression, generalized additive models, subgroup analyses, interaction tests, and ROC curves.

Key Findings:

• ALI occurred in 37.7% of patients.
• Each one-unit increase in NLR raised ALI risk by 11% (OR = 1.11, 95% CI: 1.08–1.14, P < 0.001).
• The highest NLR quartile had a 5.42-fold higher risk of ALI compared to the lowest.
• A non-linear threshold was identified at NLR = 2.92, with risk rising sharply below this point (OR = 6.55).
• NLR alone predicted ALI with AUC = 0.688 (cutoff 8.26, sensitivity 59.4%, specificity 68.0%).
• Combining NLR with CRP and gallstones improved predictive accuracy (AUC = 0.756).

Interpretation:

NLR independently predicts ALI in acute pancreatitis with a non-linear threshold effect, suggesting that even mild elevations may indicate early liver injury risk.

Limitations:

• Retrospective design may introduce bias.
• Findings may not be generalizable beyond the studied population.

Conclusion:

NLR ≥ 2.92 can serve as an early warning signal for enhanced liver function monitoring, while NLR ≥ 8.26 identifies high-risk patients. Combining NLR with other indicators improves predictive performance.