Association between Lok index and all-cause mortality among sepsis patients in critical care: insights from the MIMIC-IV database.

BACKGROUND: Sepsis is a multiple organ dysfunction syndrome, and the liver plays a significant role in the inflammatory response of sepsis. The Lok index is a common indicator of liver health, but relationship between the Lok index and sepsis prognosis is not yet clear. This study aimed to explore the association between the Lok index and clinical outcomes in patients with severe sepsis. METHOD: We extracted data on patients with sepsis from the Medical Information Database for Intensive Care IV (MIMIC-IV). Cox proportional hazards models were constructed to evaluate the relationship between Lok index and all-cause mortality at 30 days, 90 days, and 1 year. Kaplan-Meier survival curves showed the differences in mortality outcomes between different Lok index groups. Restricted cubic splines (RCS) were used to examine the dose-response relationship between Lok index and all-cause mortality risk. RESULTS: A total of 6,404 patients were included in this study and the median age of participants is 72 years, including 3,684 males (57.52%). All-cause mortality at 30, 90, and 365 days was the primary outcome, and patients were stratified into quartiles based on the Lok index. Kaplan-Meier survival curves show that a higher Lok index is associated with a higher risk of all-cause mortality at 30, 90, and 365 days (log-rank P < 0.010). Cox proportional hazards regression analysis shows that the highest quartile of Lok index had a significantly higher risk of death (HR for the fully adjusted model [HR for 30 days: 1.011 (95% CI 1.005–1.017), P < 0.001; for 90 days: 1.011 (95% CI 1.006–1.016), P < 0.001; for 1 year: 1.011 (95% CI 1.007–1.016), P < 0.001). RCS analysis reveals a significant nonlinear correlation between Lok index and all-cause mortality (P nonlinear = 0.003). In the subgroup analysis, the hazard ratio (HR) of 30-day all-cause mortality was significantly different in the atrial fibrillation (AF) and hypertension subgroup. CONCLUSION: Among patients with severe sepsis, elevated Lok index values predicted an increased likelihood of death at 30, 90, and 365 days. These findings suggest that the Lok index may serve as a novel and readily available prognostic tool for risk stratification in sepsis. CLINICAL TRIAL NUMBER: Not applicable.