Modification Of Diet In Renal Disease Study Research Articles

Do the Cockcroft-Gault (C-G), Modification of Diet in Renal Disease Study (MDRD) and Chronic Kidney Disease Epidemiology Collaboration Initiative (CKD-EPI) Equations Concur in Estimating Renal Function in Older Nursing Homes and Community Adults?

Introduction/Objective: The prevalence of CKD in older adults is high and increasing in the U.S. The National Kidney Foundation (NKF) guidelines identify 5 stages of CKD for monitoring and treatment based on creatinine clearance (CrCl) or glomerular filtration (GFR) estimates; today one may choose between C-G, MDRD and CKD-EPI formula to estimate CrCl or GFR. We derived and compared GFR estimates from the 3 formulae and examined the resultant CKD staging levels linked to these formulae in a large sample of older adults in the Bronx, NY.

Renal Function, Bisphenol A, and Alkylphenols: Results from the National Health and Nutrition Examination Survey (NHANES 2003–2006)

BackgroundUrinary excretion of bisphenol A (BPA) and alkylphenols (APs) was used as a biomarker in most previous studies, but no study has investigated whether urinary excretion of these environmental phenols differed by renal function.ObjectiveWe estimated the association between renal function and urinary excretion of BPA and APs.MethodsAnalyses were conducted using data from the National Health and Nutrition Examination Survey (NHANES) 2003–2006. Renal function was measured as estimated glomerular filtration rate (eGFR) calculated by the Modification of Diet in Renal Disease (MDRD) Study equation and by the newly developed Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Regression models were used to calculate geometric means of urinary BPA and APs excretion by eGFR category (≥ 90, 60–90, < 60 mL/min/m2) after adjusting for potential confounding factors.ResultsWhen we used the MDRD Study equation, participants without known renal disease (n = 2,573), 58.2% (n = 1,499) had mildly decreased renal function or undiagnosed chronic kidney disease. The adjusted geometric means for urinary BPA excretion decreased with decreasing levels of eGFR (p for trend = 0.04). The associations appeared primarily in females (p for trend = 0.03). Urinary triclosan excretion decreased with decreasing levels of eGFR (p for trend < 0.01) for both males and females, and the association primarily appeared in participants < 65 years of age. The association between BPA and eGFR was nonsignificant when we used the CKD-EPI equation.ConclusionsUrinary excretion of triclosan, and possibly BPA, decreased with decreasing renal function. The associations might differ by age or sex. Further studies are necessary to replicate our results and understand the mechanism.

The Relationship between Age-Related Kidney Dysfunction and Framingham Risk Score in Healthy People in China

Aging process reduces kidney function, glomerular filtration rate (GFR) and/or creatinine clearance rate (Ccr), and also significantly increases the risk level for cardiovascular diseases. The classical Framingham risk equation provides a method for predicting cardiovascular risk, but it does not include the kidney function indexes. In this study, we investigated the relationship between age-related kidney function and Framingham risk score (FRS) in healthy Chinese people, and validated to assess the risk factor by GFR/Ccr. This community-based cross-sectional study recruited 505 healthy subjects (age from 35 to 93 yr.) with both gender is during September 2007 to June 2008 in Shenyang. Framingham risk equation was used to evaluate cardiovascular risk factors and generate FRS. GFR and Ccr were calculated with Cockcroft-Gault (CG) equation (GFR(CG)), abbreviated Modification of Diet in Renal Disease Study (MDRD) equation (GFR(MDRD1)) and modified MDRD equation (GFR(MDRD2)). All data were sorted according to FRS (low, moderate and high) risk levels, and five different age groups (≤44 yr; 45-54 yr; 55-64 yr; 65-74 yr and ≥75 yr). The ANOVA, correlation, partial correlation between GFR/Ccr and FRS, as well as other risk factors were analyzed with SPSS16.0 statistical package. As the FRS level increased, GFR(CG), GFR(MDRD1), GFR(MDRD2) and Ccr decreased about 10 to 30% (low>moderate> high risk group, p<0.01). While the subjects were getting older, GFR(CG), GFR(MDRD1), GFR(MDRD2) and Ccr showed significant reduction (P<0.001). Ccr decreased about 50% from the young to oldest group (p<0.001). There was a significantly inverse correlation between FRS and GFR with Ccr having the Pearson correlation coefficient -0.586 (GFR(CG), P<0.001), - 0.449 (GFR(MDRD1) and GFR(MDRD2), P<0.001), -0.459 (Ccr, P<0.001). However, the relationship between FRS and Ccr was lost after controlling for age and other confounding variables. In healthy population, we found inverse correlations between Framingham risk score and GFR, Ccr and GFR were independently related to the FRS with similar correlation coefficient among three equations. With the increase of FRS, the GFR and Ccr decrease. Aging is the major factor of GFR and Ccr reduction in the healthy population. We suggest that GFR/Ccr could be used as risk indexes for cardiovascular diseases.

PUK22 HEALTH ECONOMIC ASPECTS OF USING SERUM CYSTATIN C FOR EARLY DETECTION OF CHRONIC KIDNEY DISEASE IN TYPE 2 DIABETICS IN GERMANY

CONTACT: Dr. Evelyn Walter IPF Institute for Pharmaeconomic Research Wolfgengasse 4/7 1010 Vienna, Austria Tel +43-1-5132007-13 Fax +43-1-5132007-15 Email: e.walter@ipf-ac.at Web: www.ipf-ac.at Objectives Diabetic nephropathy is a serious and common complication in diabetic patients. However the onset and the course of the diabetic nephropathy can be favourably influenced by appropriate therapy when detected early. In 2004 the independent international Kidney Disease Improving Global Outcome Organisation (KDIGO) recommended 2 laboratory tests for an early detection of chronic kidney disease (CKD): determination of serum creatinine to estimate glomerular filtration rate (eGFR) using the simplified equation derived from the Modification of Diet in Renal Disease Study (MDRD) and determination of proteinuria preferably microalbuminuria corrected for urine creatinine. Creatinine as a marker for eGFR has metabolic and technical limitations, especially in patients with only mild impairment of kidney function. As an alternative marker serum Cystatin C (CysC) has been proposed for early detection of CKD. Methods We developed a cost-utility-model to simulate the long-term consequences of diabetic nephropathy using CysC instead of creatinine to monitor renal function. Markov-modelling-techniques were used to describe complications and disease progression; one arm assessed the costs and effects of CysC reporting, disease progression and complications, and the other assessed the cost and effect of routine eGFR reporting. Probabilities of complications were derived from clinical and epidemiological studies. The model includes eleven a priori defined health states to describe the disease progression and occurrence of adverse events. Disease progression leads to a passover to the next health state; the others remain. The Markov-cycle length is one year.

Chronic kidney disease and 1-year survival in elderly patients discharged from acute care hospitals: a comparison of three glomerular filtration rate equations

Glomerular filtration rate (GFR) is directly associated with survival. However, the prognostic significance of GFR might be different according to the formula used to estimate it. We aimed at comparing the association between GFR estimated using three different formulas and 1-year survival in elderly patients discharged from acute care hospitals. Our series consisted of 439 patients aged 65 and older admitted to 11 acute care medical wards enrolled in a multicentre prospective observational study. GFR was estimated by body surface area-adjusted Cockcroft-Gault (CG-BSA), Modification of Diet in Renal Disease study (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas. The relative risk of mortality in patients with estimated GFR = 30-59.9 or < 30 mL/min/1.73 m(2) compared to people with estimated GFR ≥ 60 mL/min/1.73 m(2) was calculated using Cox regression analysis. Participants with reduced GFR showed an increased mortality, regardless of the equation used, and the highest one was associated with CG-BSA-estimated GFR < 30 mL/min/1.73 m(2). After adjusting for potential confounders, CKD-EPI-estimated GFR remained significantly associated with the outcome [30-59.9 mL/min/1.73 m(2), hazard ratio (HR) = 1.70, 95% confidence interval (95% CI) = 1.02-2.98; < 30 mL/min/1.73 m(2), HR = 2.60, 95% CI = 1.20-5.66], while the strength of the association was clearly reduced for MDRD (30-59.9 mL/min/1.73 m(2), HR = 1.47, 95% CI = 0.83-2.38; < 30 mL/min/1.73 m(2), HR = 2.07, 95% CI = 1.01-4.30) and CG-BSA (30-59.9 mL/min/1.73 m(2), HR = 1.79, 95% CI = 0.67-4.53; < 30 mL/min/1.73 m(2), HR = 2.68, 95% CI = 0.92-7.55). GFR adds to the list of prognostic indicators in elderly and frail people, and CKD-EPI-derived GFR, which outperforms to some extent MDRD and CG-BSA-derived GFR in a multivariable predictive model, seems worthy of testing in wider populations.

Estimation of Glomerular Filtration Rate by Using Serum Cystatin C and Serum Creatinine Concentrations in Patients with Human Immunodeficiency Virus

To compare the predictive performance of four equations for estimating glomerular filtration rate (GFR) relative to the gold standard measurement, iothalamate clearance, in patients with human immunodeficiency virus (HIV) who have various degrees of kidney function. Prospective, cross-sectional analysis. General clinical research center. Twenty-two adult (mean age 51 yrs) HIV-positive patients with various degrees of stable kidney function and with lean body mass considered normal for a well-nourished person. Patients were administered a single dose of intravenous iothalamate 456 mg as a rapid infusion over 3 minutes, 1 hour after an oral fluid load of 600 ml of caffeine-free, sugar-free liquids. Serial blood and urine samples were obtained for determination of measured GFR. Estimated GFR values were calculated by using four equations: the Cockcroft-Gault equation, the simplified Modification of Diet in Renal Disease Study (MDRD) equation, an equation that incorporates serum creatinine and cystatin C concentrations, and an equation incorporating only serum cystatin C concentration. The predictive performance of the equations was determined by comparing the bias, accuracy, and precision of the estimates with the measured values. Body composition was determined by dual-energy x-ray absorptiometry. The four predictive equations underestimated the measured GFR obtained by the iothalamate method, but the differences were not statistically significant. The MDRD equation and the equation that included both serum cystatin C and creatinine concentrations, as well as age, sex, and race, provided the least bias, most precision, and best accuracy in estimating the measured GFR. The MDRD equation and the equation that included both serum cystatin C and creatinine concentrations appear to provide accurate, precise, and relatively unbiased estimates of GFR in patients with HIV. Larger studies are needed that include patients with muscle wasting and lipodystrophy in order to validate these preliminary observations and the effects of body composition on the predictability of GFR with use of these equations.

Underestimation of impaired kidney function with serum creatinine.

Serum creatinine (SCr) levels are frequently used as a screening test to assess impaired renal function; however, patients can have significantly decreased glomerular filtration rate (GFR) with normal SCr values and making the recognition of kidney dysfunction more difficult. Hence, this study was designed to determine the extent of misclassification of the patients who have significantly reduced GFR as calculated by reexpressed four variable modification of diet in renal disease (MDRD) equation but, normal range of SCr. The study included 1040 in and out patients referred by physicians for serum creatinine measurement. When an exclusion criterion was applied 928 patients were qualified for the study. SCr was measured in 928 patients by a Roche kinetic compensated Jaffe's assay. GFR was calculated using reexpressed four variable MDRD study equation. Of the 928 patients 270 (29.1%) had renal dysfunction on the basis of eGFR (<60ml/min/1.73m(2)). However, with SCr only 162 (17.5%) patients had abnormal renal function (>1.5mg/dl) and SCr values misrepresented (108) 11.6% patients with impaired kidney function. In addition, more females, about 15% were failed to detect by SCr method in contrast to males of 9%. This study documented that, a large proportion of patients with impaired renal function are not diagnosed if clinicians rely solely on normal SCr as evidence of normal renal function. Inclusion of eGFR calculated by re-expressed 4 variable MDRD equation may facilitates the early identification and intervention of patients with renal impairment.

Renal Cortical Thickness Measured at Ultrasound: Is It Better Than Renal Length as an Indicator of Renal Function in Chronic Kidney Disease?

The purpose of our study was to determine whether there is a relationship between renal cortical thickness or length measured on ultrasound and the degree of renal impairment in chronic kidney disease (CKD). From October to December 2007, 25 patients (13 men and 12 women, mean age 73 years) were identified who had CKD but were not on dialysis. The patients were from a single institution and had undergone renal ultrasound and at least three serum creatinines within 90 days. The lowest creatinine was used for estimated glomerular filtration rate (eGFR) calculation using both the Cockcroft-Gault (CG) and the Modification of Diet in Renal Disease Study (MDRD) equations. Ultrasounds were consensus reviewed by three radiologists (2 attendings and a resident) blinded to specific renal function. Cortical thickness was measured in the sagittal plane over a medullary pyramid, perpendicular to the capsule. Length was measured pole-to-pole. Linear regression was used for statistical analysis. Mean cortical thickness was 5.9 mm (range, 3.2-11.0 mm). Mean length was 10 cm (7.2-12.4 cm). Mean minimum serum creatinine was 2.1 mg/dL (1.1-6.1 mg/dL). Mean eGFR using CG was 34.8 mL/min (10.6-99.4 mL/min) and 36 mL/min (8-66 mL/min) using MDRD. There was a statistically significant relationship between eGFR and cortical thickness using both CG (p < 0.0001) and MDRD (p = 0.005). There was a statistically significant relationship between CG and length (p = 0.003) but not between MDRD and length (p = 0.08). Cortical thickness measured on ultrasound appears to be more closely related to eGFR than renal length. Reporting cortical thickness in patients with CKD who are not on dialysis should be considered.

Evaluation of Renal Drug Dosing: Prescribing Information and Clinical Pharmacist Approaches

To characterize renal function parameters reported in United States Food and Drug Administration-approved prescribing information (package inserts), to compare dosage recommendations for patients with impaired renal function between prescribing information and tertiary drug dosing references, and to evaluate renal function quantification methods most commonly used by clinical pharmacists to develop dosage regimens. Retrospective analysis and Web-based survey. Prescribing information for all new molecular entities (NMEs) approved from 1998-2007 in which dosing recommendations were proposed for patients with impaired renal function, drug monographs from four tertiary drug dosing references (Micromedex, Lexi-Comp, Epocrates Rx, and American Hospital Formulary Service [AHFS] Drug Information) for all identified NMEs, and a Web-based survey of 204 nephrology and critical care pharmacy practitioners. A total of 44 NMEs included renal dosing recommendations in their prescribing information. For all 44 NMEs, prescribing information was reviewed to determine methods to quantify renal function, units of measure reported, and use of chronic kidney disease terminology. The most common index of renal function was creatinine clearance; the Cockcroft-Gault equation was specified in the prescribing information of 11 NMEs. Standardization for body weight was inconsistent, with prescribing information for four NMEs reporting renal function in ml/minute/1.73 m(2). The prescribing information or tertiary sources did not mention use of estimated glomerular filtration rate (eGFR) or the Modification of Diet in Renal Disease Study (MDRD) equation. Epocrates Rx provided the most abbreviated renal dosing information, whereas AHFS Drug Information was the most comprehensive, and Lexi-Comp includes a renal function calculator. Nearly all (86%) clinical pharmacists indicated that automated eGFR is reported at their institutions, although they do not use these predictions for dosing in patients with impaired renal function, and their approaches to renal function estimation varied widely. Reporting of renal function methods and dosing recommendations for patients with impaired renal function requires standardization in order to ensure optimal dosing. Pharmacy clinicians do not substitute eGFR in place of creatinine clearance for renal dosing, which is consistent with current prescribing information. Studies are needed that will evaluate the validity of using eGFR to predict drug clearance and thereby generate dosage recommendations.

Comparative Performance of the CKD Epidemiology Collaboration (CKD-EPI) and the Modification of Diet in Renal Disease (MDRD) Study Equations for Estimating GFR Levels Above 60 mL/min/1.73 m 2

The Modification of Diet in Renal Disease (MDRD) Study equation underestimates measured glomerular filtration rate (GFR) at levels>60 mL/min/1.73 m2, with variable accuracy among subgroups; consequently, estimated GFR (eGFR)>or=60 mL/min/1.73 m2 is not reported by clinical laboratories. Here, performance of a more accurate GFR-estimating equation, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, is reported by level of GFR and clinical characteristics. Test of diagnostic accuracy. Pooled data set of 3,896 people from 16 studies with measured GFR (not used for the development of either equation). Subgroups were defined by eGFR, age, sex, race, diabetes, prior solid-organ transplant, and body mass index. eGFR from the CKD-EPI and MDRD Study equations and standardized serum creatinine. Measured GFR using urinary or plasma clearance of exogenous filtration markers. Mean measured GFR was 68+/-36 (SD) mL/min/1.73 m2. For eGFR<30 mL/min/1.73 m2, both equations have similar bias (median difference compared with measured GFR). For eGFR of 30-59 mL/min/1.73 m2, bias was decreased from 4.9 to 2.1 mL/min/1.73 m2 (57% improvement). For eGFR of 60-89 mL/min/1.73 m2, bias was decreased from 11.9 to 4.2 mL/min/1.73 m2 (61% improvement). For eGFR of 90-119 mL/min/1.73 m2, bias was decreased from 10.0 to 1.9 mL/min/1.73 m2 (75% improvement). Similar or improved performance was noted for most subgroups with eGFR<90 mL/min/1.73 m2, other than body mass index<20 kg/m2, with greater variation noted for some subgroups with eGFR>or=90 mL/min/1.73 m2. Limited number of elderly people and racial and ethnic minorities with measured GFR. The CKD-EPI equation is more accurate than the MDRD Study equation overall and across most subgroups. In contrast to the MDRD Study equation, eGFR>or=60 mL/min/1.73 m2 can be reported using the CKD-EPI equation.

Imprecision of Urinary Iothalamate Clearance as a Gold-Standard Measure of GFR Decreases the Diagnostic Accuracy of Kidney Function Estimating Equations

Evaluating the accuracy of estimated glomerular filtration rate (eGFR) derived from serum creatinine (SCr) and serum cystatin C (SCysC) equations requires gold-standard measures of GFR. However, the influence of imprecise measured GFRs (mGFRs) on estimates of equation error is unknown. Diagnostic test study. 1,995 participants from the Modification of Diet in Renal Disease (MDRD) Study and African American Study of Kidney Disease and Hypertension (AASK) with at least 2 baseline mGFRs from iodine 125-iothalamate urinary clearances, 1 standardized SCr value, and 1 SCysC value. eGFRs calculated using the 4-variable isotope-dilution mass spectrometry (IDMS)-traceable MDRD Study equation, the Chronic Kidney Disease (CKD) Epidemiology Collaboration (CKD-EPI) SCysC equation, the CKD-EPI SCr-SCysC equation, and mGFRs collected from another prerandomization visit. A single reference mGFR, average of 2, and average of 3 mGFRs; additional analysis limited to consistent mGFRs (difference <or=25% from reference mGFR). We found that mGFRs had stable mean values, but substantial variability across visits. Of all mGFRs collected a mean of 62 days apart from the reference visit, 8.0% were outside 30% of the single reference mGFR (1 - P(30)). Estimation equations were less accurate because 12.1%, 17.1%, and 8.3% of eGFRs from the MDRD Study, CKD-EPI SCysC, and CKD-EPI SCr-SCysC equations were outside 30% of the same gold standard (1 - P(30)). However, improving the precision of the reference test from a single mGFR to the average of 3 consistent mGFRs decreased these error estimates (1 - P(30)) to 8.0%, 12.5%, and 3.9%, respectively. Study population limited to those with CKD. Imprecision in gold-standard measures of GFR contribute to an appreciable proportion of the cases in which eGFR and mGFR differ by >30%. Reducing and quantifying errors in gold-standard measurements of GFR is critical to fully estimating the accuracy of GFR estimates.

日本人における糸球体濾過量 (GFR) 推算式の比較検討

Creatinine clearance (Ccr) is widely used for the evaluation of the glomerular filtration rate (GFR). Since the clearance method requires urine collection, formulae for predicting GFR without urine collection have been developed. In the guidelines of the Kidney Disease Outcomes Quality Initiative(K/ DOQI), the formulae developed from the Modification of Diet in Renal Disease Study (MDRD) are recommended for estimating GFR. The objective of the present study is to compare measured Ccr and Ccr estimated by the Cockcroft-Gault, Horio and MDRD equations in Japanese adults. In 100 inpatients (67 men and 33 women) in this hospital, we evaluated the correlation between measured Ccr derived from 24-hour urinary collections and predicted Ccr or GFR calculated using the Cockcroft-Gault, Horio, and MDRD equations. The equation of linear regression is given as y = 0.8165x+2.1229 (r = 0.9415, p < 0.0001) by the Cockcroft-Gault formula, y = 0.7478x+1.6757 (r = 0.9458, p < 0.0001) by the Horio formula and y = 0.8335x+4.4261 (r = 0.9209, p < 0.0001) by the MDRD formula (y : measured Ccr, x : estimated Ccr or GFR). These predictive formulae demonstrated a strong correlation. Although the Cockcroft-Gault formula derived from Japanese patients demonstrated the highest correlation with Ccr, both the Horio formula and the MDRD formula also showed a high correlation. These predictive formulae could be useful for the prediction of Ccr in Japanese patients.

Modification of the CKD Epidemiology Collaboration (CKD-EPI) Equation for Japanese: Accuracy and Use for Population Estimates

We previously reported a modification to the Modification of Diet in Renal Disease (MDRD) Study equation for use in Japan. Recently, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) developed a new equation that is more accurate and yields a lower CKD prevalence estimate in the United States than the MDRD Study equation. We modified the CKD-EPI equation for use in Japan, compared its accuracy with the Japanese modification of the MDRD Study equation, and compared the prevalence of CKD in Japan using both equations. A diagnostic test study comparing the Japanese coefficient-modified CKD-EPI equation and Japanese coefficient-modified MDRD Study equation and a cross-sectional study comparing distribution of estimated glomerular filtration rate and prevalence of CKD in participants in a Japanese annual health check program. 763 Japanese patients (413 for development and 350 for validation) were included. Prevalence estimates were based on 574,024 participants from the annual health check program. Japanese modification of the MDRD Study and CKD-EPI equations. Inulin clearance. The Japanese coefficient of the modified CKD-EPI equation was 0.813 (95% CI, 0.794-0.833). In the validation data set, the modified CKD-EPI equation performed better than the modified MDRD Study equation. Bias (measured GFR [mGFR] - eGFR) was 0.4 +/- 17.8 (SD) versus 1.3 +/- 19.8 mL/min/1.73 m(2) overall, respectively (P = 0.02); 7.3 +/- 20.6 versus 7.8 +/- 22.2 mL/min/1.73 m(2) for participants with mGFR >or=60 mL/min/1.73 m(2), respectively (P < 0.001); and -4.4 +/- 13.8 versus -3.3 +/- 15.6 mL/min/1.73 m(2) for participants with mGFR <60 mL/min/1.73 m(2), respectively (P = 0.5). The modified CKD-EPI equation yields a lower estimated prevalence of CKD than the modified MDRD Study equation (7.9% vs 10.0%), primarily because of a lower estimated prevalence of stage 3 (5.2% vs 7.5%). Most study participants had CKD. The study population contained a limited number of participants with mGFR >or=90 mL/min/1.73 m(2). The Japanese coefficient-modified CKD-EPI equation is more accurate than the Japanese coefficient-modified MDRD Study equation and leads to a lower estimated prevalence of CKD in Japan.

818 CHRONIC KIDNEY DISEASE PRIOR AND FOLLOWING NEPHRON-SPARING SURGERY

You have accessJournal of UrologyKidney Cancer: Localized I1 Apr 2010818 CHRONIC KIDNEY DISEASE PRIOR AND FOLLOWING NEPHRON-SPARING SURGERY Melanie Clark, Sergey Shikanov, Jay Raman, Benjamin Smith, Matthew Kaag, Paul Russo, Jeffrey C. Wheat, J. Stuart Wolf, Surena Matin, William Huang, Arieh Shalhav, and Scott E. Eggener Melanie ClarkMelanie Clark Chicago, IL More articles by this author , Sergey ShikanovSergey Shikanov Chicago, IL More articles by this author , Jay RamanJay Raman Hershey, PA More articles by this author , Benjamin SmithBenjamin Smith Hershey, PA More articles by this author , Matthew KaagMatthew Kaag Hershey, PA More articles by this author , Paul RussoPaul Russo New York, NY More articles by this author , Jeffrey C. WheatJeffrey C. Wheat Ann Arbor, MI More articles by this author , J. Stuart WolfJ. Stuart Wolf Ann Arbor, MI More articles by this author , Surena MatinSurena Matin Houston, TX More articles by this author , William HuangWilliam Huang New York, NY More articles by this author , Arieh ShalhavArieh Shalhav Chicago, IL More articles by this author , and Scott E. EggenerScott E. Eggener Chicago, IL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1519AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We performed a multi-institutional retrospective cohort study to evaluate baseline renal function of patients who underwent partial nephrectomy for renal tumors and determine rates of progression to higher stages of chronic kidney disease (CKD). METHODS Preoperative and postoperative serum creatinine values were obtained from patients who underwent partial nephrectomy at six institutions with a normal contralateral kidney and had baseline CKD of I (GFR > 90 ml/min/1.73m2), II (GFR = 60 – 89 ml/min/1.73m2), or III (GFR = 30 – 59 ml/min/1.73m2). Patients with baseline CKD IV and V were excluded. The Modification of Diet in Renal Disease Study (MDRD) equation was used to estimate glomerular filtration rate (GFR) and determine CKD stage. The endpoint was change in CKD at long-term follow-up (3–18 months). A multivariate logistic regression model tested the association of newly acquired CKD III with age, sex, race, BMI, surgical approach, hypertension, diabetes, coronary artery disease, tumor size and margins, renal vessel clamping, ischemia time, hypothermia, and estimated blood loss. RESULTS A total of 1,228 patients underwent partial nephrectomy with follow-up creatinine data at least 3 months following surgery. Mean baseline GFR was 75 ml/min/1.73m2. At baseline, 19% of patients had CKD I, 59% had CKD II, and 22% had CKD III. At long-term follow-up, mean post-operative GFR for patients with baseline CKD I or II was 71 ml/min/1.73m2 with 280 (29%) patients newly entering CKD III. Increasing age (OR = 1.05, p <0.001), female gender (OR = 1.80 p = 0.002), increasing tumor size (OR = 1.20, p = 0.003), clamping the renal artery and vein (B = 2.28, p = 0.054), and lower pre-operative GFR (OR = 1.05, p <0.001) were independently associated with newly acquired CKD III. The presence of co-morbid conditions did not independently predict increased risk of a higher CKD stage. CONCLUSIONS Approximately one-quarter of patients presenting for partial nephrectomy with a normal contralateral kidney have stage III CKD and an additional 29% will develop CKD III or higher following surgery. Increasing age, female gender, larger tumor size, clamping the artery and vein, and lower baseline GFR are associated with worsening kidney function following surgery. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e320 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Melanie Clark Chicago, IL More articles by this author Sergey Shikanov Chicago, IL More articles by this author Jay Raman Hershey, PA More articles by this author Benjamin Smith Hershey, PA More articles by this author Matthew Kaag Hershey, PA More articles by this author Paul Russo New York, NY More articles by this author Jeffrey C. Wheat Ann Arbor, MI More articles by this author J. Stuart Wolf Ann Arbor, MI More articles by this author Surena Matin Houston, TX More articles by this author William Huang New York, NY More articles by this author Arieh Shalhav Chicago, IL More articles by this author Scott E. Eggener Chicago, IL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Prognostic value of chronic kidney disease in patients with coronary heart disease: Role of estimating equations

ObjectiveChronic kidney disease (CKD) increases risk of coronary heart disease (CHD), but the impact of using different equations for estimating kidney function on CHD is not clear yet. This study described the prognostic value of CKD as defined by various creatinine- (Cr-eGFR) and cystatin C-based estimating (Cys-eGFR) equations and their combinations on subsequent cardiovascular disease (CVD) events in patients with CHD. DesignCohort study. SettingPatients with coronary heart disease in in-patient rehabilitation and long-term follow-up (mean 63.4 months). Subjects1050 patients with coronary heart disease aged 30–70 years at baseline. MethodsCKD was defined as eGFR<60mL/min/1.73m2 (CKD stages 3–5) estimated by three Cr-eGFR equations (Cockroft–Gault equation adjusted for body surface area (CG/BSA), Modification of Diet in Renal Disease Study (MDRD) equation, CKD-EPIcrea) and by two Cys-eGFR equations (Arnal-Dade equation, CKD-EPIcys) and a combination. The primary endpoint of our study was subsequent CVD events. ResultsDuring follow-up 118 patients (11.2%) experienced the outcome of our study. CKD assessed by the CG/BSA, MDRD, and CKD-EPIcrea equations showed no statistically significant association with subsequent CVD events after adjustment for multiple covariates (hazard ratio (HR) 1.45 [95% CI, 0.81–2.59], HR 1.47 [95% CI, 0.84–2.60], and HR 1.31 [95% CI, 0.72–2.83], respectively). By contrast, the Cys-eGFR equations were much stronger associated with subsequent CVD endpoints (Arnal-Dade: HR, 2.01 [95% CI, 1.34–3.04]; CKD-EPIcys HR, 2.22 [95% CI, 1.46–3.37]). The CKD-EPIcys also provided the highest area under the curve value. ConclusionOur study shows that prevalent CKD is an independent risk factor for subsequent CVD in patients with prevalent CHD and implies that Cys-eGFR equations show a better clinical utility compared to the Cr-eGFR equations.

Estimating Glomerular Filtration Rate in Kidney Transplantation: Is the New Chronic Kidney Disease Epidemiology Collaboration Equation Any Better?

The new Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was developed to address the systematic underestimation of the glomerular filtration rate (GFR) by the Modification of Diet in Renal Disease (MDRD) Study equation in patients with a relatively well-preserved kidney function. The performance of the new equation for kidney transplant recipients (KTRs) is unknown. We used the plasma clearance of (99m)Tc-diethylenetriamine pentaacetic acid to measure the GFR in a cohort of 207 stable KTRs and estimated the GFR with the new CKD-EPI equation. The mean bias for the CKD-EPI equation of -4.5 mL x min(-1) x (1.73 m(2))(-1) was lower than that of the 4-variable MDRD Study equation; however, the 2 equations showed similar variation of individual biases around the mean or median bias, so that only modest improvement was seen in the overall percentage of GFR estimates within 30% of the measured GFR (84% vs 77% for the CKD-EPI vs MDRD Study equations, respectively). In the cohort with a GFR >60 mL x min(-1) x (1.73 m(2))(-1) (n = 98), the CKD-EPI bias was much less than that of the MDRD Study equation [-7.4 mL x min(-1) x (1.73 m(2))(-1) vs -14.3 mL x min(-1) x (1.73 m(2))(-1)], and an accuracy of + or - 30% was seen for 89% of GFR estimates, compared with 77% with the MDRD Study equation. The variation of the individual biases around the mean bias remained substantial [SD = 13.7 mL x min(-1) x (1.73 m(2))(-1)]. The CKD-EPI equation shows improved estimation ability, and we recommend that it replace the MDRD Study equation as the currently preferred creatinine-based estimating equation for KTRs. The precision of GFR estimates obtained with the CKD-EPI equation remains suboptimal, however, and we recommend that research on other markers of GFR, such as cystatin C and beta-trace protein, be pursued.

Risk Implications of the New CKD Epidemiology Collaboration (CKD-EPI) Equation Compared With the MDRD Study Equation for Estimated GFR: The Atherosclerosis Risk in Communities (ARIC) Study

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) recently published an equation for estimated glomerular filtration rate (eGFR) using the same variables (serum creatinine level, age, sex, and race) as the Modification of Diet in Renal Disease (MDRD) Study equation. Although the CKD-EPI equation estimates GFR more precisely compared with the MDRD Study equation, whether this equation improves risk prediction is unknown. Prospective cohort study, the Atherosclerosis Risk in Communities (ARIC) Study. 13,905 middle-aged participants without a history of cardiovascular disease with median follow-up of 16.9 years. eGFR. We compared the association of eGFR in categories (>or=120, 90-119, 60-89, 30-59, and <30 mL/min/1.73 m(2)) using the CKD-EPI and MDRD Study equations with risk of incident end-stage renal disease, all-cause mortality, coronary heart disease, and stroke. The median value for eGFR(CKD-EPI) was higher than that for eGFR(MDRD) (97.6 vs 88.8 mL/min/1.73 m(2); P < 0.001). The CKD-EPI equation reclassified 44.9% (n = 3,079) and 43.5% (n = 151) of participants with eGFR(MDRD) of 60-89 and 30-59 mL/min/1.73 m(2), respectively, upward to a higher eGFR category, but reclassified no one with eGFR(MDRD) of 90-119 or <30 mL/min/1.73 m(2), decreasing the prevalence of CKD stages 3-5 from 2.7% to 1.6%. Participants with eGFR(MDRD) of 30-59 mL/min/1.73 m(2) who were reclassified upward had lower risk compared with those who were not reclassified (end-stage renal disease incidence rate ratio, 0.10 [95% CI, 0.03-0.33]; all-cause mortality, 0.30 [95% CI, 0.19-0.48]; coronary heart disease, 0.36 [95% CI, 0.21-0.61]; and stroke, 0.50 [95% CI, 0.24-1.02]). Similar results were observed for participants with eGFR(MDRD) of 60-89 mL/min/1.73 m(2). More frequent reclassification of younger, female, and white participants explained some of these trends. Net reclassification improvement in participants with eGFR < 120 mL/min/1.73 m(2) was positive for all outcomes (P < 0.001). Limited number of cases with eGFR < 60 mL/min/1.73 m(2) and no measurement of albuminuria. The CKD-EPI equation more appropriately categorized individuals with respect to long-term clinical risk compared with the MDRD Study equation, suggesting improved clinical usefulness in this middle-aged population.

Comparison of the Prevalence and Mortality Risk of CKD in Australia Using the CKD Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) Study GFR Estimating Equations: The AusDiab (Australian Diabetes, Obesity and Lifestyle) Study

The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) is more accurate than the Modification of Diet in Renal Disease (MDRD) Study equation. We applied both equations in a cohort representative of the Australian adult population. Population-based cohort study. 11,247 randomly selected noninstitutionalized Australians aged >or= 25 years who attended a physical examination during the baseline AusDiab (Australian Diabetes, Obesity and Lifestyle) Study survey. Glomerular filtration rate (GFR) was estimated using the MDRD Study and CKD-EPI equations. Kidney damage was defined as urine albumin-creatinine ratio >or= 2.5 mg/mmol in men and >or= 3.5 mg/mmol in women or urine protein-creatinine ratio >or= 0.20 mg/mg. Chronic kidney disease (CKD) was defined as estimated GFR (eGFR) >or= 60 mL/min/1.73 m(2) or kidney damage. Participants were classified into 3 mutually exclusive subgroups: CKD according to both equations; CKD according to the MDRD Study equation, but no CKD according to the CKD-EPI equation; and no CKD according to both equations. All-cause mortality was examined in subgroups with and without CKD. Serum creatinine and urinary albumin, protein, and creatinine measured on a random spot morning urine sample. 266 participants identified as having CKD according to the MDRD Study equation were reclassified to no CKD according to the CKD-EPI equation (estimated prevalence, 1.9%; 95% CI, 1.4-2.6). All had an eGFR >or= 45 mL/min/1.73 m(2) using the MDRD Study equation. Reclassified individuals were predominantly women with a favorable cardiovascular risk profile. The proportion of reclassified individuals with a Framingham-predicted 10-year cardiovascular risk >or= 30% was 7.2% compared with 7.9% of the group with no CKD according to both equations and 45.3% of individuals retained in stage 3a using both equations. There was no evidence of increased all-cause mortality in the reclassified group (age- and sex-adjusted hazard ratio vs no CKD, 1.01; 95% CI, 0.62-1.97). Using the MDRD Study equation, the prevalence of CKD in the Australian population aged >or= 25 years was 13.4% (95% CI, 11.1-16.1). Using the CKD-EPI equation, the prevalence was 11.5% (95% CI, 9.42-14.1). Single measurements of serum creatinine and urinary markers. The lower estimated prevalence of CKD using the CKD-EPI equation is caused by reclassification of low-risk individuals.

Ethnic coefficients for glomerular filtration rate estimation by the Modification of Diet in Renal Disease study equations in the Korean population.

Race and ethnicity are influential in estimating glomerular filtration rate (GFR). We aimed to find the Korean coefficients for the Modification of Diet in Renal Disease (MDRD) study equations and to obtain novel proper estimation equations. Reference GFR was measured by systemic inulin clearance. Serum creatinine (SCr) values were measured by the alkaline picrate Jaffé kinetic method, then, recalibrated to CX3 analyzer and to isotope dilution mass spectrometry (IDMS). The Korean coefficients for the 4 and 6 variable MDRD and IDMS MDRD study equations based on the SCr recalibrated to CX3 and to IDMS were 0.73989/0.74254 and 0.99096/0.9554, respectively. Coefficients for the 4 and 6 variable MDRD equations based on the SCr measured by Jaffé method were 1.09825 and 1.04334, respectively. The modified equations showed better performances than the original equations. The novel 4 variable equations for Korean based on the SCr measured and recalibrated to IDMS were 107.904×SCr-1.009×age-0.02 (×0.667, if woman) and 87.832×SCr-0.882×age0.01 (×0.653, if woman), respectively. Modified estimations of the MDRD and IDMS MDRD study equations with ethnic coefficients and the novel equations improve the performance of GFR estimation for the overall renal function.

The CKD-EPI Equation and MDRD Study Equation Find Similar Prevalence of Chronic Kidney Disease in Asian Populations

Letters15 December 2009The CKD-EPI Equation and MDRD Study Equation Find Similar Prevalence of Chronic Kidney Disease in Asian PopulationsCharumathi Sabanayagam, MD, MMed, Tien Y. Wong, MD, PhD, and E. Shyong Tai, MBChBCharumathi Sabanayagam, MD, MMedFrom Singapore Eye Research Institute, National Institute of Singapore, Singapore, 168751, Singapore.Search for more papers by this author, Tien Y. Wong, MD, PhDFrom Singapore Eye Research Institute, National Institute of Singapore, Singapore, 168751, Singapore.Search for more papers by this author, and E. Shyong Tai, MBChBFrom Singapore Eye Research Institute, National Institute of Singapore, Singapore, 168751, Singapore.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-151-12-200912150-00014 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:Levey and colleagues (1) presented a new equation for estimating glomerular filtration rate (GFR), the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and compared the prevalence of chronic kidney disease (CKD) in the U.S. population estimated by the new equation with the prevalence estimated by the MDRD (Modification of Diet in Renal Disease) Study equation. The authors reported that the new CKD-EPI equation gives a lower estimated prevalence of CKD than the MDRD Study equation and suggested testing this new equation in other ethnic groups. Recent studies in Asian populations show that the epidemiologic pattern and the relative ...