Concordance Among Methods for Empiric Renal Drug Dosing: Meropenem as a Role Model for Clinical Superiority of Cockroft–Gault or Modification of Diet in Renal Disease

Abstract

Objective: The objectives of this study are, first, to measure concordance between 5 different renal function estimates (methods) in terms of recommended drug doses, and, subsequently, to establish the potential for significant clinical differences between Cockroft–Gault (CG) and Modification of Diet in Renal Disease (MDRD) equations in dosing a specific medication, namely, meropenem. Design and setting: This study used a Monte Carlo simulation, and this is a computer–based study with no actual patient data. Patients: A total of 1200 and 8701 simulated cases to study the concordance for the 5 methods and the potential clinical significance of discordance between CG and MDRD, respectively, were chosen for the study. Methods: Simulated factors were age, sex, height, weight, serum creatinine, ethnicity, and albumin. We estimated the renal function using 5 formulas (ie, 10 combinations) including CG, MDRD, and Chronic Kidney Disease Epidemiology Collaboration (CKD–EPI). Next, the team evaluated concordance for each combination in dosing 22 drugs. Finally, our researchers reviewed and simulated data from the literature to show how CG versus MDRD use can result in clinically significant differences for meropenem. Results: Pairwise combinations yielded statistically significant differences (P