胆红素系统检测在老年心力衰竭患者死亡风险预测中的价值

Value of bilirubin system detection in predicting mortality risk in elderly patients with heart failure

目的探讨胆红素系统检测在老年心力衰竭(心衰)患者死亡风险预测中的应用价值。方法选择2013年11月~2015年11月于上海市同仁医院心血管内科收治的慢性心力衰竭患者50例(心衰组),同期选取体检健康人群40例为对照组,比较两组受试者的B型脑利钠肽前体(NT-proBNP)、左心室舒张末期内径(LVEDD)、左室射血分数(LVEF)、总胆红素、间接胆红素、直接胆红素水平。心衰组患者以全因死亡为终点事件,随访2年。应用受试者工作特征曲线(ROC)计算确定与死亡率相关的胆红素切点值,依据切点值将50例心衰组患者分为胆红素水平正常组和胆红素水平升高组两个亚组。比较两亚组的生存率,分析胆红素与临床指标的相关性以及对心衰患者全因死亡的预测价值。结果心衰组患者的NT-proBNP、总胆红素、间接胆红素、直接胆红素水平高于对照组,LVEDD大于对照组,LVEF低于对照组,差异均有统计学意义(P<0.05);ROC曲线计算与死亡率相关的总胆红素、间接胆红素及直接胆红素切点值分别为23.50μmol/L、17.69μmol/L及4.60μmol/L,Kaplan-Meier生存曲线分析显示,总胆红素、间接胆红素、直接胆红素水平升高均可增加心衰患者的死亡风险。经Spearman相关性分析显示,总胆红素、间接胆红素及直接胆红素水平均与NT-proBNP、尿酸(UA)呈正相关(P<0.05);与LVEF呈负相关(P<0.05)。在考虑到年龄、性别、肾功能、肝功能及血脂等因素后,总胆红素对心衰患者全因死亡仍有独立预测价值(P<0.01)。结论胆红素与心衰患者全因死亡独立相关,胆红素系统水平的升高是心衰患者全因死亡的独立预测因素。

Objective To discuss the application value of bilirubin system detection in predicting mortality risk in elderly patients with chronic heart failure(CHF).Methods CHF patients(n=50,CHF group)and health controls(n=40,control group)were chosen from Department of Cardiovascular Medicine in Tongren Hospital of Shanghai City from Nov.2013 to Nov.2015.The indexes of NT-proBNP,left ventricular end-diastolic inner diameter(LVEDd),left ventricular ejection fraction(LVEF),total bilirubin(TBIL),indirect bilirubin(IBIL)and direct bilirubin(DBIL)were compared between 2 groups.Taken all-cause mortality as endpoint event,CHF group was followed up for 2 y.The bilirubin cut-off value related to mortality was calculated by using receiver operating characteristic curve(ROC),and CHF group(n=50)were divided,according to the cut-off,into normal bilirubin subgroup and higher bilirubin subgroup.The survival rate was compared,and correlation between bilirubin and clinical indexes and predictive value of bilirubin to all-cause mortality were analyzed in 2 subgroups.Results The levels of NT-proBNP,TBIL,IBIL and DBIL were higher,LVEDd was higher and LVEF was lower in CHF group than those in control group(P<0.05).The cut-off value related to mortality,calculated by using ROC,of TBIL was 23.50μmol/L,of IBIL was 17.69μmol/L and of DBIL was 4.60μmol/L.The analysis of Kaplan-Meier survival curve showed that the elevations of TBIL,IBIL and DBIL promoted mortality risk in CHF patients.The results of Spearman correlation analysis showed that levels of TBIL,IBIL and DBIL were positively correlated to NT-proBNP and uric acid(P<0.05),and negatively correlated to LVEF(P<0.05).After considering age,sex,kidney function,liver function and blood fat,TBIL still had independent predictive value to all-cause mortality in CHF patients.Conclusion Bilirubin is independently correlated to all-cause mortality,and elevation of bilirubin system level is an independent predictive factor of all-cause mortality in CHF patients.