Relationship between the laboratory test-based frailty index and overall mortality in critically ill patients with acute pancreatitis: a retrospective study based on the MIMIC-IV database

Li Jin ¹ Yanyan Dong ¹ Junpeng Xu ² Maosheng Chen ² Rui-Xiang Zeng ^2* Liheng Guo ^2*

• ¹ Second Clinical Medical College, Guangzhou University of Traditional Chinese Medicine, Guangzhou, China
• ² Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, China

Background and Aims: The frailty index based on lab tests helps identify at-risk individuals, but its link to mortality in acute pancreatitis ICU patients is unclear. This study explores the association between the frailty index and all-cause mortality in these patients and assesses its prognostic value.Methods: We conducted a retrospective study using the MIMIC-IV database, focusing on first-time ICU admissions with acute pancreatitis (age ≥ 18). The frailty index (FI-lab) included three vital signs and 30 lab tests. Patients were grouped by FI-lab quartiles. Kaplan-Meier analysis assessed 28-day mortality differences, while Cox proportional hazards analysis explored the relationship between FI-lab and mortality. We also used Harrell’s C, IDI, and NRI to compare FI-lab's predictive capability to traditional metrics.Results: The study included 741 patients. Kaplan-Meier analysis showed higher FI-lab scores correlated with increased mortality risk (P < 0.0001). Cox regression analysis indicated a 0.01 increment in FI-lab raised 28-day mortality risk [HR 1.072, 95% CI (1.055-1.089), P < 0.001]. Patients in the highest FI-lab quartile had significantly higher mortality risk [HR 9.933, 95% CI (4.676-21.104), P < 0.001]. Adding FI-lab to conventional severity scores improved mortality prediction.Conclusions: The FI-lab score is a reliable indicator of short-term mortality in ICU patients with acute pancreatitis. Early detection and intervention using FI-lab are crucial for improving prognoses.