Application of neutrophil-to-lymphocyte-to-monocyte ratio in predicting mortality risk in adult patients with septic shock: A retrospective cohort study conducted at a single center.

Background: Sepsis is a life-threatening condition characterized by an aberrant host response to infection, resulting in multi-organ dysfunction. The application of currently available prognostic indicators for sepsis in primary hospitals is challenging. In this retrospective study, we established a novel index, the neutrophil-to-lymphocyte-to-monocyte ratio (NLMR), based on routine blood examination upon admission, and assessed its prognostic value for early mortality risk in adult patients with septic shock. Methods: This study included clinical data from adult patients with septic shock who were admitted to the hospital between January 1, 2018, and December 31, 2022. Training and validation sets were constructed, and patients were categorized into "survival" and "death" groups based on their survival status within the 28-day hospitalization period. Baseline data, including demographic characteristics and comorbidities, and laboratory results, such as complete blood count parameters, were collected for analysis. The Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were documented.The NLMR was determined through the utilization of multivariate binary logistic regression analysis, leading to the development of a risk model aimed at predicting early mortality in adult patients suffering from septic shock. Results: Overall, 112 adult patients with septic shock were enrolled in this study, with 84 and 28 patients in the training and validation sets, respectively. Multivariate binary logistic analysis revealed that the neutrophil, lymphocyte, and monocyte counts independently contributed to the mortality risk (odds ratios = 1.22, 0.08, and 0.16, respectively). The NLMR demonstrated an area under the receiver operating characteristic curve (ROC-AUC) of 0.83 for internal validation in the training set and 0.97 for external validation in the validation set. Both overall model quality values were significantly high at 0.74 and 0.91, respectively (P < 0.05). NLMR exhibited a higher ROC-AUC value of 0.88 than quick SOFA (ROC-AUC = 0.71), SOFA (ROC-AUC = 0.83), and APACHE II (ROC-AUC = 0.78). Conclusion: NLMR may be a potential marker for predicting the risk of early death in adult patients with septic shock, warranting further exploration and verification.