Lapuerta P, Rajan S, Bonacini M
Department of Internal Medicine, University of Southern California School of Medicine, Los Angeles, USA.
Hepatology. 1997 Feb;25(2):302-6. doi: 10.1053/jhep.1997.v25.pm0009021938.
We developed and evaluated neural networks as predictors of outcomes in alcoholic patients with severe liver disease using commonly available clinical and laboratory values. Hospital charts of 144 patients were reviewed. Nine variables (five laboratory, four clinical) were recorded along with in-hospital death or survival. Data were organized into separate development and validation sets. Neural network predictions of survival were compared with those of the Maddrey discriminant function and logistic regression models developed on the same data. Model performance was evaluated by comparing areas under receiver-operating characteristic (ROC) curves and the distributions of model scores. Survivors had significantly different laboratory and clinical characteristics, the most important being a higher prothrombin time, lower bilirubin, and lower incidence of encephalopathy. Neural network performance was significantly better than that of the Maddrey score (ROC areas, 81.5% vs. 73.8%; P = .04). The ROC area for neural networks was similar to that of logistic regression (ROC area 78.2%; P = .3), but the neural networks were more successful in classifying patients into low- and high-risk groups (P < .001). A neural network score with laboratory data from hospital-day 7 improved prognostic accuracy further to 84.3%. After adjusting for baseline risk, the neural network change in illness severity was still a significant predictor of mortality (P = .001). Neural networks using clinical and laboratory data showed a high prognostic accuracy for predicting mortality in alcoholic patients with severe liver disease.
我们利用常见的临床和实验室检查值,开发并评估了神经网络,将其作为重症酒精性肝病患者预后的预测指标。我们回顾了144例患者的医院病历。记录了9项变量(5项实验室指标、4项临床指标)以及患者在住院期间的死亡或存活情况。数据被分为独立的开发集和验证集。将神经网络对存活情况的预测结果与基于相同数据开发的Maddrey判别函数及逻辑回归模型的预测结果进行比较。通过比较受试者工作特征(ROC)曲线下面积及模型评分分布来评估模型性能。存活患者的实验室检查和临床特征存在显著差异,其中最重要的是凝血酶原时间较长、胆红素水平较低以及肝性脑病发生率较低。神经网络的性能显著优于Maddrey评分(ROC曲线下面积分别为81.5%和73.8%;P = 0.04)。神经网络的ROC曲线下面积与逻辑回归相似(ROC曲线下面积为78.2%;P = 0.3),但神经网络在将患者分为低风险和高风险组方面更为成功(P < 0.001)。结合第7天医院实验室数据得出的神经网络评分进一步将预后准确性提高到了84.3%。在对基线风险进行校正后,神经网络所反映的疾病严重程度变化仍然是死亡率的显著预测指标(P = 0.001)。利用临床和实验室数据的神经网络在预测重症酒精性肝病患者的死亡率方面显示出较高的预后准确性。