Upper Normal Serum Creatinine Concentrations as a Predictor for Chronic Kidney Disease: Analysis of 14 Years' Korean Genome and Epidemiology Study (KoGES).

Jong Jhee,Seun Hwang,Joon Song,Seoung Lee

doi:10.3390/jcm7110463

Abstract

Both serum creatinine (sCr) and estimated glomerular filtration rate (eGFR) have been used to assess kidney function in public health check-ups. However, when the sCr is within the normal levels but the eGFR is <60 mL/min/1.73 m2, a dilemma arises, as the patients might progress to chronic kidney disease (CKD) after several years. We aimed to evaluate the association between normal sCr and the risk of incident CKD in the general population. For this, 9445 subjects from the Korean Genome and Epidemiology Study, with normal sCr and eGFR of >60 mL/min/1.73 m2 were analyzed. The subjects were classified into quartiles based on sCr levels. The primary outcome was the development of eGFR <60 mL/min/1.73 m2 on two consecutive measures. During a mean follow-up of 8.4 ± 4.3 years, 779 (8.2%) subjects developed eGFR <60 mL/min/1.73 m2. The incidence of the development of eGFR <60 mL/min/1.73 m2 was higher in the higher quartiles than in the lowest quartile. In multivariable Cox analysis, the highest quartile was associated with an increased risk for the development of eGFR <60 mL/min/1.73 m2 (hazard ratio (HR), 4.71; 95% confidence interval (CI), 3.29–6.74 in females; HR, 12.77; 95% CI, 7.69–21.23 in males). In the receiver operating characteristic curve analysis, adding sCr to the traditional risk factors for CKD improved the accuracy of predicting the development of eGFR <60 mL/min/1.73 m2 (area under the curve, 0.83 vs. 0.80 in females and 0.85 vs. 0.78 in males), and the cutoff value of sCr was 0.75 mg/dL and 0.78 mg/dL in females and males. Cautious interpretation is necessary when sCr is within the normal range, considering that the upper normal range of sCr has a higher risk of CKD development.

Highlights

Chronic kidney disease (CKD) is increasingly recognized as a major global public health problem [1]
In KNHSP, the presence of CKD is determined by either high serum creatinine (sCr) (>1.5 mg/dL) or low estimated glomerular filtration rate, and the patient is notified of “suspected kidney dysfunction”. When both sCr and eGFR are used to screen for CKD in KNHCP, primary care physicians face a challenge in the diagnosis of CKD
This might lead to a debate that (1) the upper normal limit of sCr should be reset to be equal to an eGFR of 60 mL/min/1.73 m2, and (2) sCr close to the upper normal limit might have a higher risk for CKD

Summary

Introduction

Chronic kidney disease (CKD) is increasingly recognized as a major global public health problem [1]. In KNHSP, the presence of CKD is determined by either high sCr (>1.5 mg/dL) or low estimated glomerular filtration rate (eGFR 60 mL/min/1.73 m2 are not aware of their kidney function and there is no management strategy for such cases

Objectives

Methods

Results

Conclusion