摘要
AIM:To evaluate pre-lung transplant acid reflux on p H-testing vs corresponding bolus reflux on multichannel intraluminal impedance(MII) to predict early allograft injury.METHODS:This was a retrospective cohort study of lung transplant recipients who underwent pretransplant combined MII-p H-testing at a tertiary care center from January 2007 to November 2012. Patients with pre-transplant fundoplication were excluded. Time-to-event analysis was performed using a Cox proportional hazards model to assess associations between measures of reflux on MII-p H testing and early allograft injury. Area under the receiver operating characteristic(ROC) curve(c-statistic) of the Cox model was calculated to assess the predictive value of each reflux parameter for early allograft injury. Six p H-testing parameters and their corresponding MIImeasures were specified a priori. The p H parameters were upright,recumbent,and overall acid reflux exposure; elevated acid reflux exposure; total acid reflux episodes; and acid clearance time. The corresponding MII measures were upright,recumbent,and overall bolus reflux exposure; elevated bolus reflux exposure; total bolus reflux episodes; and bolus clearance time.RESULTS:Thirty-two subjects(47% men,mean age:55 years old) met the inclusion criteria of the study. Idiopathic pulmonary fibrosis(46.9%) repres e n t e d t h e m o s t c o m m o n p u l m o n a r y d i a g n o s i s leading to transplantation. Baseline demographics,pre-transplant cardiopulmonary function,number of lungs transplanted(unilateral vs bilateral),and posttransplant proton pump inhibitor use were similar between reflux severity groups. The area under the ROC curve,or c-statistic,of each acid reflux parameter on pre-transplant p H-testing was lower than its bolus reflux counterpart on MII in the prediction of early allograft injury. In addition,the development of early allograft injury was significantly associated with three pre-transplant MII measures of bolus reflux:overall reflux exposure(HR = 1.18,95%CI:1.01-1.36,P = 0.03),recumbent reflux exposure(HR = 1.25,95%CI:1.04-1.50,P = 0.01) and bolus clearance(HR = 1.09,95%CI:1.01-1.17,P = 0.02),but not with any p Htesting parameter measuring acid reflux alone.CONCLUSION:Pre-transplant MII measures of bolus reflux perform better than their p H-testing counterparts in predicting early allograft injury post-lung transplantation.
AIM:To evaluate pre-lung transplant acid reflux on p H-testing vs corresponding bolus reflux on multichannel intraluminal impedance(MII) to predict early allograft injury.METHODS:This was a retrospective cohort study of lung transplant recipients who underwent pretransplant combined MII-p H-testing at a tertiary care center from January 2007 to November 2012. Patients with pre-transplant fundoplication were excluded. Time-to-event analysis was performed using a Cox proportional hazards model to assess associations between measures of reflux on MII-p H testing and early allograft injury. Area under the receiver operating characteristic(ROC) curve(c-statistic) of the Cox model was calculated to assess the predictive value of each reflux parameter for early allograft injury. Six p H-testing parameters and their corresponding MIImeasures were specified a priori. The p H parameters were upright,recumbent,and overall acid reflux exposure; elevated acid reflux exposure; total acid reflux episodes; and acid clearance time. The corresponding MII measures were upright,recumbent,and overall bolus reflux exposure; elevated bolus reflux exposure; total bolus reflux episodes; and bolus clearance time.RESULTS:Thirty-two subjects(47% men,mean age:55 years old) met the inclusion criteria of the study. Idiopathic pulmonary fibrosis(46.9%) repres e n t e d t h e m o s t c o m m o n p u l m o n a r y d i a g n o s i s leading to transplantation. Baseline demographics,pre-transplant cardiopulmonary function,number of lungs transplanted(unilateral vs bilateral),and posttransplant proton pump inhibitor use were similar between reflux severity groups. The area under the ROC curve,or c-statistic,of each acid reflux parameter on pre-transplant p H-testing was lower than its bolus reflux counterpart on MII in the prediction of early allograft injury. In addition,the development of early allograft injury was significantly associated with three pre-transplant MII measures of bolus reflux:overall reflux exposure(HR = 1.18,95%CI:1.01-1.36,P = 0.03),recumbent reflux exposure(HR = 1.25,95%CI:1.04-1.50,P = 0.01) and bolus clearance(HR = 1.09,95%CI:1.01-1.17,P = 0.02),but not with any p Htesting parameter measuring acid reflux alone.CONCLUSION:Pre-transplant MII measures of bolus reflux perform better than their p H-testing counterparts in predicting early allograft injury post-lung transplantation.