The Clinical Applied Evaluation Of Glomerular Filtration Rate Estimated Formulae In Glycometabolic Disorder Subjects

Objective:To analyze the influencing factors of diabetic nephropathy and evaluate the applied value of Cockcroft-Gault formula,simplified MDRD formula and modified simplified MDRD formula in glycometabolic disorder subjects.Meanwhile,we tend to develop a new GFR estimated formula specialized for diabetes in order to assist clinical treatment.Methods:454 patients(as the First Group) who had accepted examination of ^99mTc-diethylenetriaminepentaacetic acid(^99mTc-DTPA)nephro-dynamic imaging GFR in the first affiliated hospital of JI NAN University during January 2000 to January 2009 were treated as case groups,containing the second Group,which contained 188 diabetes who had normal ultrasound examination result in urinary system and had no history in kidney diseases,and the third Group,which contained 130 diabetes who had been hospitalized in the first affiliated hospital of JI NAN University during January 2000 to January 2009.Using ^99mTc-DTPA nephro-dynamic imaging GFR as gold standard,compare the coincidence of the three known formulae with the gold standard separately at different glycometabolic stations and analyze the influencing factors of the glomerular filtration function of the diabetics.Using the data from diabetic subjects as study cases,to develop a new formula by redrawing into new parameters and compare the coincidence with the gold standard between the new one and the three known formulae at different GFR levels while evaluating the GFR of the diabetics and the non-diabetics.Results:1.Coincidence between the known formulae and gold standard:â‘ With regard to the mixed subjects,Cockcroft-Gault formula underestimated the GFR while simplified MDRD formula and modified simplified MDRD formula overestimated the GFR,the difference of which had statistic significance.Regard to the patients after CKD4,the estimated value of the three formulae was near indistinctively,comparing with gold stantard.â‘¡Regard to the non-diabetics,Cockcroft-Gault formula underestimated the GFR of the CKD1 and CKD2 patients,simplified MDRD formula underestimated the GFR of CKD1 patients but overestimated the GFR of CKD3,modified simplified MDRD formula overestimated the GFR of CKD3 patients,all of which had statistic significance.For the diabetics,Cockcroft-Gault formula underestimated the GFR of CKD1 and CKD2 patients,simplified MDRD formula overestimated the GFR of CKD2 and CKD3 patients,modified simplified MDRD formula overestimated the GFR of CKD2 to CKD3 patients,all of which had statistic significance.Finally for the CKD4 and CKD5 patients,the estimated value of the three formulae were similar whatever the glycometabolic station,the difference of which had no statistic significance.2.Influencing factors analysis of diabetic nephropathy:â‘ Glycometabolic disorther with hypertension had lower GFR and higher urinary albumin excretion rate,and GFR had negative correlation with hypertension course.But the differences of the urinary albumin excretion rate and the urinary albumin/urinary creatinine ratio between each CKD stage had no statistic significance.â‘¡The GFR had negative correlation with age,body surface area,diabetic course,retinopathy level, systolic blood pressure,serum creatinine,blood urea nitrogen and blood uric acid while having positive correlation with glycosylated hemoglobin,fasting plasma glucose and high density lipoprotein C.â‘¢The GFR of the diabetics with nonproliferative diabetic retinopathy was lower than the group with normal fundus,the difference of which had statistic significance.3. Comparison between the new formula based on the data from diabetes and the three known formulae:the new one had higher sensitivity(77.62%) and specificity(85.19%).The coincidence of the new formula with the gold standard was 0.72,which was better than the three known formulae when it was applied in a certain diabetic subjects,but was inferior when applied in mixed subjects.Conclusions:Diabetic nephropathy is a disease affected by multiple factors,which had distinct pathogenic mechanism.Using the known formulae which was applied to the patients with chronic kidney disease was insufficient when being applied to evaluate the GFR of the diabetics.The new formula based on the diabetics had higher sensitivity and specificity,which may help to more accurately evaluate the GFR of the diabetics in clinical practice.However,this study was limited by the research subjects,thus it can only be applied to the limited diabetics temporarily.