基于XGBoost和SHAP的急性肾损伤可解释预测模型

An Interpretable Prediction Model for Acute Kidney Injury Based on XGBoost and SHAP

重症监护病房(ICU)住院期间发生的急性肾损伤(AKI)与患者发病率和死亡率的增加有关。该研究的目的是提出一个基于机器学习的框架,用于危重病患者的可解释AKI预测,该框架能够同时实现良好的预测和解释能力。该文从重症监护医学信息数据库Ⅲ(MIMIC-Ⅲ)中提取的数据包括患者的年龄、性别、生命体征和ICU入院第1天及随后的化验值。在该研究中,通过将XGBoost模型与其他4种机器学习模型进行比较,证明了XGBoost模型的预测性能。此外,SHAP(SHapley Additive exPlanation)模型可解释器用于提供个性化评估和解释,以实现个性化的临床决策支持。结果表明,XGBoost能较好地预测AKI,与以往的预测模型相比,此模型更为简单有效,仅用21个特征变量即得到了更稳定的预测结果,预测精度高,模型准确率和受试者工作特征曲线下面积(AUC)分别为0.824和0.840,均高于既往研究结果。此外,该文对两组指标进行了特征依赖分析,发现24h尿量减少和血尿素氮升高可增加AKI风险。综上所述,该可解释预测模型可能有助于临床医生更准确快速地识别重症监护中存在AKI风险的患者,为患者提供更好的治疗。此外,可解释性框架的使用增加了模型透明度,便于临床医生分析预测模型的可靠性。

The development of Acute Kidney Injury(AKI) during admission to the Intensive Care Unit(ICU) is associated with increased morbidity and mortality. The objective of this study is to develop a machine learningbased framework for interpretable AKI prediction in critical care that can achieve both good prediction and interpretation capability. Data extracted from the Medical Information Mart for Intensive Care Ⅲ(MIMIC-Ⅲ)include patient age, gender, vital signs and lab values during the first day of ICU admission and subsequent hospitalization. In this study, the prediction performance of the XGBoost model is demonstrated by comparing it to four other machine learning models. In addition, the SHapley Additive exPlanation(SHAP) framework is used to provide individualized evaluation and explanations to enable personalized clinical decision support. The results show that XGBoost can predict AKI robustly with an Accuracy and the area Under the receiver operating Characteristic curve(AUC) of 0.824 and 0.840, respectively, which are higher than previous prediction models. Furthermore, a feature dependency analysis is conducted for two pairs of features and found decrease in urine volume and elevation of blood urea nitrogen indicates an increase of AKI risk. To sum up, this interpretable predictive model may help clinicians more accurately identify patients at risk of AKI in intensive care and provide better treatment for patients. In addition, the use of this interpretability framework increases model transparency and facilitates clinicians to analyze the reliability of predictive models.