Association of Glomerular Filtration Rate With Slow Coronary Flow in Patients With Normal to Mildly Impaired Renal Function

Abstract

We thank Cabuk et al 1 for their comments. 2 They raise concerns about the equation used for reporting estimated glomerular filtration rate (eGFR) in our study and how this could impact on our results. The equation from the Modification of Diet in Renal Disease (MDRD) Study is frequently used to report the eGFR. We agree that the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is more accurate than the MDRD Study equation, particularly in patients with a GFR 60 mL/ min/1.73 m 2 . 3 The MDRD Study equation has been evaluated in several populations, including African Americans, Europeans, and Asians. 4,5 Several studies have shown that the MDRD Study equation has reasonable accuracy in nonhospitalized patients thought to have CKD and patients with and without diabetes or kidney disease.

Is there a relationship between slow coronary flow and normal to mildly impaired renal function?

“…However, this formula is being abandoned in clinical practice. Akin et al [14] investigated this association in patients with normal and mildly decreased results calculated with MDRD were also included in analysis. No association between SCF and normal to mildly impaired renal function was found using the CKD-EPI equation.…”

“…[13][14][15] However, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation is preferred when reporting estimated glomerular filtration rate (eGFR), particularly in patients with mildly decreased GFR. [16] The CKD-EPI equation was developed in 2009, in an effort to address underestimation in patients with eGFR ≥60 ml/min/1.73 m 2 using the MDRD equation.…”

Which Calculation Method of Glomerular Filtration Rate is Suitable in Patients With Normal or Mildly Impaired Renal Function?

“…Finally, the National Kidney Disease Education Program recommends calibrating serum creatinine measurement to isotope dilution mass spectrometry. 8 In the “Laboratory Measurements” section of the article, Akin et al 1 mention cholesterol, uric acid, and hemoglobin measurements but the most important parameter of this study, creatinine, was not mentioned.…”

“…We read the article entitled “Association of Glomerular Filtration Rate With Slow Coronary Flow in Patients With Normal to Mildly Impaired Renal Function” by Akin et al 1 with interest. The authors 1 concluded that estimated glomerular filtration rate (eGFR) was significantly correlated with slow coronary flow in patients with normal to mildly impaired kidney function.…”

“…7 Altered muscle mass (eg, reduced by amputation, paraplegia, immobilization, or a neuromuscular disorder and increased by dietary protein intake or creatine dietary supplements), some medications (like aminoglycosides or trimethoprim), and dietary intake (eg, vegetarians) can affect the creatinine levels and eGFR. 7 Akin et al 1 did not mention these factors as exclusion criteria.…”