Initial lactate levels and 14-day mortality in ischemic stroke: A retrospective cohort study using the MIMIC-IV...

Ischemic stroke is a leading cause of death and disability worldwide, and early prognostic assessment is crucial for optimizing patient management. Lactate is an important biomarker reflecting tissue hypoxia and metabolic disorders, and its relationship with short-term mortality risk has not been fully clarified. This study aimed to explore the association between early lactate levels on admission and the risk of mortality within 14 days in patients with ischemic stroke. This study was a retrospective cohort study based on the Medical Information Mart for Intensive Care IV database. Cases with high-risk underlying diseases such as hypertension and diabetes were excluded. Univariate and multivariate logistic regression analyses were used to evaluate the relationship between lactate levels and short-term mortality risk, and the receiver operating characteristic curve was used to analyze the predictive ability of lactate and other biochemical indicators. In addition, subgroup analysis was performed to explore the interaction of biochemical indicators in patient groups with different mortality risks. A total of 157 patients with ischemic stroke were included, comprising 107 in the survival group and 50 in the death group. Univariate analysis showed that lactate levels were significantly associated with 14-day mortality (P < .05), but multivariable logistic regression analysis revealed that lactate levels were not independent risk factors (P > .05). Potassium and sodium ion levels were independent risk factors for short-term mortality (P < .05). Receiver operating characteristic analysis showed that the area under the curve of lactate, potassium, and sodium ions was between 0.60 and 0.70, indicating limited predictive ability. Subgroup analysis found that lactate was associated with sodium, chloride, and blood glucose levels in the survival group, while lactate was associated with calcium, sodium, and chloride ions in the non-survival group, suggesting potential differences in lactate-electrolyte interactions between groups in different populations. Initial lactate levels were associated with 14-day mortality in univariate analysis but were not an independent predictor after multivariable adjustment. Sodium and potassium levels were independently associated with short-term mortality in patients with ischemic stroke. The discriminative performance of lactate alone was limited (area under the curve = 0.637, 95% confidence interval: 0.546-0.728).