Comparison of equations for estimating glomerular filtration rate in screening for chronic kidney disease in asymptomatic black Africans: a cross sectional study

Abstract

BackgroundSeveral equations have been developed to estimate glomerular filtration rate (eGFR). The common equations used were derived from populations predominantly comprised of Caucasians with chronic kidney disease (CKD). Some of the equations provide a correction factor for African-Americans due to their relatively increased muscle mass and this has been extrapolated to black Africans. Studies carried out in Africa in patients with CKD suggest that using this correction factor for the black African race may not be appropriate. However, these studies were not carried out in healthy individuals and as such the extrapolation of the findings to an asymptomatic black African population is questionable. We sought to compare the proportion of asymptomatic black Africans reported as having reduced eGFR using various eGFR equations. We further compared the association between known risk factors for CKD with eGFR determined using the different equations.MethodsWe used participant and laboratory data collected as part of a global reference interval study conducted by the Committee of Reference Intervals and Decision Limits (C-RIDL) under the International Federation of Clinical Chemistry (IFCC). Serum creatinine values were used to calculate eGFR using the Cockcroft-Gault (CG), re-expressed 4 variable modified diet in renal disease (4v–MDRD), full age spectrum (FAS) and chronic kidney disease epidemiology collaboration equations (CKD-EPI). CKD classification based on eGFR was determined for every participant.ResultsA total of 533 participants were included comprising 273 (51.2%) females. The 4v–MDRD equation without correction for race classified the least number of participants (61.7%) as having an eGFR equivalent to CKD stage G1 compared to 93.6% for CKD-EPI with correction for race. Only age had a statistically significant linear association with eGFR across all equations after performing multiple regression analysis. The multiple correlation coefficients for CKD risk factors were higher for CKD-EPI determined eGFRs.ConclusionsThis study found that eGFR determined using CKD-EPI equations better correlated with a prediction model that included risk factors for CKD and classified fewer asymptomatic black Africans as having a reduced eGFR compared to 4v–MDRD, FAS and CG corrected for body surface area.

Cox regression of factors associated with the onset of chronic kidney disease in HIV/AIDS patients in Albert Luthuli Municipality of South Africa

“…The finding that CKD is associated with baseline creatinine, age and gender is not novel as these are the components of the GFR formula (Iseki, 2008;Omuse et al, 2017). Therefore, the concurrence of the regression results with the existing formula confirms the appropriateness and accuracy of the research methods used.…”

“…The estimates of the final Cox PH modelOmuse et al (2017). Treatment (regimen one) is also included in this section because of its clinical significance among the HIV/AIDS patients.…”

Performance of the CKD-EPI and MDRD equations to estimate the glomerular filtration rate: a systematic review of Latin American studies

“…including Asian (36), Japanese (37), Chinese (38), Pakistanis (39), and African (12). However, previous attempts to modify the CKD-EPI-Cr formula for Latin American populations (40) and Brazilian population (33) found no significant improvements of the modified versus the original formula.…”

“…Differences in the performance of these equations across certain ethnic groups have been reported (12)(13)(14), and attributed to differences in the production and excretion of creatinine (15) which, in turn, is related to diet (protein intake) and muscle mass (endogenous production of creatinine) that varies according to ethnicity (15,16). Thus, it is possible that results from regions with different ethnic compositions such as Europe or North America, which are mostly Caucasian, cannot be extrapolated to Latin American populations that are composed of a mixture of Amerindians, Mestizos, Blacks, Asians, and Caucasians (17).…”

Estimating Glomerular Filtration Rate Using Full Age Spectrum Equation to Assess Kidney Function in Hypertensive Patients: A Cross-sectional Study

“…Mainly, the very first Cockcroft and Gault (CG) equation [5] followed by Modification of Diet in Renal Disease (MDRD) equation [6], Hoek's formula [7], then Chronic Kidney Disease-Epidemiological collaboration (CKD-EPI) equation [8,9] and very recent Full Age Spectrum (FAS) equations [10,11] have been developed for estimating GFR (eGFR). eGFR based on FAS equation has been evaluated in Korean adults [12], black Africans [13], Europeans [14] and Chinese subjects [15,16].…”