Estimation of Glomerular Filtration Rate in South Asians: A Study from the General Population in Pakistan

• Activity Number: 444
• Type: Contributed
• Date/Time: Tuesday, August 6, 2013 : 2:00 PM to 3:50 PM
• Sponsor: Survey Research Methods Section
• Author(s): Muhammad Islam*+ and Saleem Jesani and Andrew S. Levey and Rasool Bux and Lesley A. Inker and Nish Chaturvedi and Christophe Mariat and Christopher Schmid and Tazeen H. Jafar
• Companies: Aga Khan University and Aga Khan University and Tufts Medical Center and Aga Khan University and Tufts Medical Center and Imperial College London and University de Saint-Etienne and Brown University and Aga Khan University
• Keywords: GFR ; Estimating equations ; South Asians

Abstract

Objective: The objectives of the study were to evaluate and modify the performance of existing eGFR equations in South-Asians. METHODS:GFR(mGFR) was measured by using urinary clearance of inulin in 581 adults in a cross-sectional study conducted in Karachi, Pakistan. CKD-EPI and MDRD Study equations were assessed and correction factor for CKD-EPI equation was derived and modified using linear regression. The main outcome measures were bias, precision, RMSE and accuracy P30 reported as cross validated estimates along with bootstrapped 95%CI based on 1000 replications. RESULTS: The CKD-EPI equation performed better than the MDRD equation in terms of lower RMSE p< 0.001, greater accuracy at P30 p< 0.001 and improved precision p< 0.001. However, both equations overestimated GFR. The application of a correction factor(0.7xeGFR CKD-EPI1.059) to CKD-EPI for eliminating bias improved accuracy p< 0.001. The performance of new equations developed in South-Asians was comparable to the modified South-Asian CKD-EPI equation. CONCLUSIONS:CKD-EPI is more accurate and precise than the MDRD Study equation in estimating GFR in South-Asian population in Karachi and should be preferred for eGFR reporting.