Bedside rapid lactate-creatinine-to-platelet ratio score and short-term mortality prognosis in patients with aspiration pneumonia complicated by sepsis: a multicenter cohort study

This study aimed to investigate the association between the rapid bedside Lactate-Creatinine-to-Platelet Ratio (LCPR) and short- to medium-term mortality prognosis in patients with aspiration pneumonia complicated by sepsis. This retrospective database-based observational study included a total of 3241 patients with aspiration pneumonia complicated by sepsis, with the MIMIC-IV 3.1 database serving as the training cohort ( n = 1738) and the eICU 2.0 database as the validation cohort ( n = 1503). Cox survival analysis was performed to evaluate the association between LCPR and mortality. Receiver operating characteristic (ROC) curve analysis was used to assess the predictive value of LCPR for mortality. Subgroup analyses were conducted to explore the relationship between LCPR and mortality across different patient subgroups. Restricted cubic spline (RCS) analysis was employed to investigate potential threshold effects and nonlinear relationships between LCPR and short- to medium-term mortality risk. Kaplan–Meier survival analysis and Cox survival analysis were further used to validate the identified LCPR thresholds. Cox regression analysis showed that LCPR was significantly associated with increased 28-day and 90-day mortality in both cohorts ( P < 0.05). ROC analysis demonstrated that LCPR exhibited superior discriminative performance compared with the SOFA score for predicting short- and intermediate-term mortality ( P DeLong = 0.0001; P DeLong < 0.0001). Subgroup analyses identified a significant interaction between LCPR and mortality in the age subgroup of the MIMIC-IV 3.1 cohort, whereas no significant interactions were observed in the eICU 2.0 cohort. Restricted cubic spline analysis revealed a nonlinear association with a threshold effect, with mortality risk increasing markedly when LCPR exceeded 1.05 ( P < 0.001). Kaplan–Meier and Cox analyses further confirmed that LCPR >1.05 was associated with significantly lower survival and higher 28-day and 90-day mortality ( P < 0.001). The rapid bedside LCPR score is an important risk factor for short- and medium-term mortality in patients. Its predictive performance for short- and medium-term mortality is superior to that of the SOFA score. LCPR exhibits a threshold effect (LCPR = 1.05) and a nonlinear relationship with mortality, providing a practical bedside tool for rapid risk stratification in this patient population.