@article {1385, title = {Comparison of risk prediction using the CKD-EPI equation and the MDRD study equation for estimated glomerular filtration rate.}, journal = {JAMA}, volume = {307}, year = {2012}, month = {2012 May 09}, pages = {1941-51}, abstract = {

CONTEXT: The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation more accurately estimates glomerular filtration rate (GFR) than the Modification of Diet in Renal Disease (MDRD) Study equation using the same variables, especially at higher GFR, but definitive evidence of its risk implications in diverse settings is lacking.

OBJECTIVE: To evaluate risk implications of estimated GFR using the CKD-EPI equation compared with the MDRD Study equation in populations with a broad range of demographic and clinical characteristics.

DESIGN, SETTING, AND PARTICIPANTS: A meta-analysis of data from 1.1 million adults (aged >= 18 years) from 25 general population cohorts, 7 high-risk cohorts (of vascular disease), and 13 CKD cohorts. Data transfer and analyses were conducted between March 2011 and March 2012.

MAIN OUTCOME MEASURES: All-cause mortality (84,482 deaths from 40 cohorts), cardiovascular mortality (22,176 events from 28 cohorts), and end-stage renal disease (ESRD) (7644 events from 21 cohorts) during 9.4 million person-years of follow-up; the median of mean follow-up time across cohorts was 7.4 years (interquartile range, 4.2-10.5 years).

RESULTS: Estimated GFR was classified into 6 categories (>=90, 60-89, 45-59, 30-44, 15-29, and <15 mL/min/1.73 m(2)) by both equations. Compared with the MDRD Study equation, 24.4\% and 0.6\% of participants from general population cohorts were reclassified to a higher and lower estimated GFR category, respectively, by the CKD-EPI equation, and the prevalence of CKD stages 3 to 5 (estimated GFR <60 mL/min/1.73 m(2)) was reduced from 8.7\% to 6.3\%. In estimated GFR of 45 to 59 mL/min/1.73 m(2) by the MDRD Study equation, 34.7\% of participants were reclassified to estimated GFR of 60 to 89 mL/min/1.73 m(2) by the CKD-EPI equation and had lower incidence rates (per 1000 person-years) for the outcomes of interest (9.9 vs 34.5 for all-cause mortality, 2.7 vs 13.0 for cardiovascular mortality, and 0.5 vs 0.8 for ESRD) compared with those not reclassified. The corresponding adjusted hazard ratios were 0.80 (95\% CI, 0.74-0.86) for all-cause mortality, 0.73 (95\% CI, 0.65-0.82) for cardiovascular mortality, and 0.49 (95\% CI, 0.27-0.88) for ESRD. Similar findings were observed in other estimated GFR categories by the MDRD Study equation. Net reclassification improvement based on estimated GFR categories was significantly positive for all outcomes (range, 0.06-0.13; all P < .001). Net reclassification improvement was similarly positive in most subgroups defined by age (<65 years and >=65 years), sex, race/ethnicity (white, Asian, and black), and presence or absence of diabetes and hypertension. The results in the high-risk and CKD cohorts were largely consistent with the general population cohorts.

CONCLUSION: The CKD-EPI equation classified fewer individuals as having CKD and more accurately categorized the risk for mortality and ESRD than did the MDRD Study equation across a broad range of populations.

}, keywords = {African Continental Ancestry Group, Aged, Algorithms, Asian Continental Ancestry Group, Cardiovascular Diseases, Cohort Studies, Decision Support Techniques, European Continental Ancestry Group, Female, Glomerular Filtration Rate, Humans, Kidney Failure, Chronic, Male, Middle Aged, Models, Theoretical, Risk Assessment, Sex Factors}, issn = {1538-3598}, doi = {10.1001/jama.2012.3954}, author = {Matsushita, Kunihiro and Mahmoodi, Bakhtawar K and Woodward, Mark and Emberson, Jonathan R and Jafar, Tazeen H and Jee, Sun Ha and Polkinghorne, Kevan R and Shankar, Anoop and Smith, David H and Tonelli, Marcello and Warnock, David G and Wen, Chi-Pang and Coresh, Josef and Gansevoort, Ron T and Hemmelgarn, Brenda R and Levey, Andrew S} } @article {6554, title = {Decline in estimated glomerular filtration rate and subsequent risk of end-stage renal disease and mortality.}, journal = {JAMA}, volume = {311}, year = {2014}, month = {2014 Jun 25}, pages = {2518-2531}, abstract = {

IMPORTANCE: The established chronic kidney disease (CKD) progression end point of end-stage renal disease (ESRD) or a doubling of serum creatinine concentration (corresponding to a change in estimated glomerular filtration rate [GFR] of -57\% or greater) is a late event.

OBJECTIVE: To characterize the association of decline in estimated GFR with subsequent progression to ESRD with implications for using lesser declines in estimated GFR as potential alternative end points for CKD progression. Because most people with CKD die before reaching ESRD, mortality risk also was investigated.

DATA SOURCES AND STUDY SELECTION: Individual meta-analysis of 1.7 million participants with 12,344 ESRD events and 223,944 deaths from 35 cohorts in the CKD Prognosis Consortium with a repeated measure of serum creatinine concentration over 1 to 3 years and outcome data.

DATA EXTRACTION AND SYNTHESIS: Transfer of individual participant data or standardized analysis of outputs for random-effects meta-analysis conducted between July 2012 and September 2013, with baseline estimated GFR values collected from 1975 through 2012.

MAIN OUTCOMES AND MEASURES: End-stage renal disease (initiation of dialysis or transplantation) or all-cause mortality risk related to percentage change in estimated GFR over 2 years, adjusted for potential confounders and first estimated GFR.

RESULTS: The adjusted hazard ratios (HRs) of ESRD and mortality were higher with larger estimated GFR decline. Among participants with baseline estimated GFR of less than 60 mL/min/1.73 m2, the adjusted HRs for ESRD were 32.1 (95\% CI, 22.3-46.3) for changes of -57\% in estimated GFR and 5.4 (95\% CI, 4.5-6.4) for changes of -30\%. However, changes of -30\% or greater (6.9\% [95\% CI, 6.4\%-7.4\%] of the entire consortium) were more common than changes of -57\% (0.79\% [95\% CI, 0.52\%-1.06\%]). This association was strong and consistent across the length of the baseline period (1 to 3 years), baseline estimated GFR, age, diabetes status, or albuminuria. Average adjusted 10-year risk of ESRD (in patients with a baseline estimated GFR of 35 mL/min/1.73 m2) was 99\% (95\% CI, 95\%-100\%) for estimated GFR change of -57\%, was 83\% (95\% CI, 71\%-93\%) for estimated GFR change of -40\%, and was 64\% (95\% CI, 52\%-77\%) for estimated GFR change of -30\% vs 18\% (95\% CI, 15\%-22\%) for estimated GFR change of 0\%. Corresponding mortality risks were 77\% (95\% CI, 71\%-82\%), 60\% (95\% CI, 56\%-63\%), and 50\% (95\% CI, 47\%-52\%) vs 32\% (95\% CI, 31\%-33\%), showing a similar but weaker pattern.

CONCLUSIONS AND RELEVANCE: Declines in estimated GFR smaller than a doubling of serum creatinine concentration occurred more commonly and were strongly and consistently associated with the risk of ESRD and mortality, supporting consideration of lesser declines in estimated GFR (such as a 30\% reduction over 2 years) as an alternative end point for CKD progression.

}, keywords = {Adult, Aged, Aged, 80 and over, Cohort Studies, Creatinine, Disease Progression, Endpoint Determination, Female, Glomerular Filtration Rate, Humans, Kidney Failure, Chronic, Male, Middle Aged, Reference Values, Risk}, issn = {1538-3598}, doi = {10.1001/jama.2014.6634}, author = {Coresh, Josef and Turin, Tanvir Chowdhury and Matsushita, Kunihiro and Sang, Yingying and Ballew, Shoshana H and Appel, Lawrence J and Arima, Hisatomi and Chadban, Steven J and Cirillo, Massimo and Djurdjev, Ognjenka and Green, Jamie A and Heine, Gunnar H and Inker, Lesley A and Irie, Fujiko and Ishani, Areef and Ix, Joachim H and Kovesdy, Csaba P and Marks, Angharad and Ohkubo, Takayoshi and Shalev, Varda and Shankar, Anoop and Wen, Chi Pang and de Jong, Paul E and Iseki, Kunitoshi and Stengel, B{\'e}n{\'e}dicte and Gansevoort, Ron T and Levey, Andrew S} }