Wu Yue, Huang Nannan, Sun Tienan, Zhang Biyang, Zhang Shiyu, Zhang Pengyu, Zhang Chunxia
Xingtai People's Hospital, Xingtai 054031, Hebei, China.
Xingtai People's Hospital, Xingtai 054031, Hebei, China.
Int J Cardiol. 2024 Mar 15;399:131658. doi: 10.1016/j.ijcard.2023.131658. Epub 2023 Dec 23.
Lactate was a prognostic indicator for acute myocardial infarction (AMI) patients. However, the association between normalized lactate load, representing hypoxic burden over time, and in-hospital mortality remained uncertain.
The data for this study was obtained from the Medical Information Mart for Intensive Care IV (MIMIC-IV, version 2.1) database. The normalized lactate load, describing the average intensity of hyperlactatemia, was calculated as the area under the curve (AUC) of lactate divided by time. 5882 AMI patients enrolled in this study were divided into survivor (n = 5015), and non-survivor group (n = 867). The primary endpoint was in-hospital mortality. Receiver operating characteristic (ROC) curves were generated to assess the predictive efficacy of normalized lactate load for in-hospital mortality, and areas under the curves of different parameters were compared using DeLong test. Multivariate binary logistic regression analysis was employed to explore the association between normalized lactate load and in-hospital mortality. The adjusting variables included age, gender, ethnicity, heart rate, systolic blood pressure, congestive heart failure, shock, dyslipidemia, cardiac arrest, cerebrovascular disease, neutrophil, lymphocyte, creatinine, blood nitrogen urea, clopidogrel, beta-blockers, angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB), statins, dialysis, extracorporeal membrane oxygenation (ECMO), the Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score II (SAPS II). Restricted cubic spline (RCS) was conducted to evaluate nonlinear associations of normalized lactate load with in-hospital mortality.
The overall in-hospital mortality rate was 14.7%. After adjusting for confounding variables, normalized lactate load was independently associated with increased risk of in-hospital mortality (Normalized lactate load≥2.6 vs Normalized lactate load<2.6: OR, 95% CI: 1.56, 1.27-1.93). The RCS demonstrated a positive linear relationship between normalized lactate load and in-hospital mortality (non-linear p = 0.725). ROC curves showed that normalized lactate load was better than first lactate, maximum lactate, and mean lactate in predicting in-hospital mortality, but lower than SOFA and SAPS II. Among participants with at least nine lactate measures, normalized lactate load showed predictive performance comparable to SOFA and SAPS II.
Normalized lactate load can be used to predict the prognosis of in-hospital mortality in AMI patients, and its prediction performance increases with the increase of lactate measurement.
乳酸是急性心肌梗死（AMI）患者的一个预后指标。然而，代表随时间变化的缺氧负担的标准化乳酸负荷与院内死亡率之间的关联仍不确定。
本研究的数据来自重症监护医学信息集市IV（MIMIC-IV，版本2.1）数据库。标准化乳酸负荷用于描述高乳酸血症的平均强度，计算方法为乳酸曲线下面积（AUC）除以时间。本研究纳入的5882例AMI患者被分为存活组（n = 5015）和非存活组（n = 867）。主要终点是院内死亡率。绘制受试者工作特征（ROC）曲线以评估标准化乳酸负荷对院内死亡率的预测效能，并使用DeLong检验比较不同参数曲线下的面积。采用多因素二元逻辑回归分析来探讨标准化乳酸负荷与院内死亡率之间的关联。调整变量包括年龄、性别、种族、心率、收缩压、充血性心力衰竭、休克、血脂异常、心脏骤停、脑血管疾病、中性粒细胞、淋巴细胞、肌酐、血尿素氮、氯吡格雷、β受体阻滞剂、血管紧张素转换酶抑制剂（ACEI）/血管紧张素受体阻滞剂（ARB）、他汀类药物、透析、体外膜肺氧合（ECMO）、序贯器官衰竭评估（SOFA）评分和简化急性生理学评分II（SAPS II）。进行限制立方样条（RCS）分析以评估标准化乳酸负荷与院内死亡率之间的非线性关联。
总体院内死亡率为14.7%。在调整混杂变量后，标准化乳酸负荷与院内死亡风险增加独立相关（标准化乳酸负荷≥2.6 vs标准化乳酸负荷<2.6：比值比，95%置信区间：1.56，1.27 - 1.93）。RCS分析显示标准化乳酸负荷与院内死亡率之间呈正线性关系（非线性p = 0.725）。ROC曲线显示，在预测院内死亡率方面，标准化乳酸负荷优于首次乳酸值、最高乳酸值和平均乳酸值，但低于SOFA评分和SAPS II评分。在至少有9次乳酸测量值的参与者中，标准化乳酸负荷的预测性能与SOFA评分和SAPS II评分相当。
标准化乳酸负荷可用于预测AMI患者的院内死亡预后，且其预测性能随乳酸测量次数的增加而提高。
