한국인에서 CKD-EPI 공식과 MDRD 공식 적용에 따른 추정 사구체여과율과 대사증후군 유병률의 연관성 비교

Dept. of International Health/석사Glomerular filtration rate (GFR), a best marker for overall kidney function, has been estimated using the Modification of Diet in Renal Disease (MDRD) Study equation. The MDRD Study has been criticized for its inaccuracy at higher GFR range. Newly developed equation by Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) was validated to be more accurate in higher GFR range and performed better in prognostication than the MDRD Study equation. Metabolic syndrome, a cluster of interrelated risk factors for ASCVD, has been closely related to chronic kidney disease (CKD). We aimed to study whether reclassification of GFR categories by the CKD-EPI equation improves the association between estimated kidney function and prevalence of metabolic syndrome.MethodsWe performed a cross-sectional analysis of data from 12,700 community population 19 years and older those who participated in the Korea Health and Nutritional Examination Survey (KNHANES) conducted in 2009 and 2010. GFR was estimated by using CKD-EPI equation and the MDRD Study equation and then categorized according to expanded version of Kidney Disease Outcomes Quality Initiative CKD classification. Metabolic syndrome was defined according to revised National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. Net reclassification improvement analyses were done to assess the additive value of the CKD-EPI equation over the MDRD Study equation.ResultsThe mean value for estimated GFR by using the CKD-EPI equation (eGFRCKD-EPI) was higher than that of eGFRMDRD (96.8 ± 17.1 vs. 90.3 ± 17.5 mL/min/1.73m2). Participants reclassified to higher eGFRCKD-EPI categories compared with eGFRMDRD were less likely to have metabolic syndrome components including hypertension, impaired fasting glucose, obesity, and dyslipidemia in overall range, whereas those reclassified to lower eGFRCKD-EPI categories were more likely to have higher risk profile. The predicted 10-year cardiovascular risk for individuals in each cross-tabulated eGFR category also showed similar pattern. The prevalence of metabolic syndrome was increased in graded trend from highest eGFR category (>120 mL/min/1.73m2) to lowest (105 mL/min/1.73m2) using both equations but only eGFRCKD-EPI showed independent association at 75-89 mL/min/1.73m2 (OR 1.21, 95% CI 1.02-1.43, P = 0.025), whereas eGFRMDRD) did not (OR 1.02, 95% CI 0.88-1.19, P = 0.793).ConclusionThe CKD-EPI equation more appropriately reclassified individuals with respect to prevalence of metabolic syndrome and its components compared with the MDRD Study equation, which leaded to an independent association of metabolic syndrome with decreased kidney function even at normal to mildly impaired range. The improved accuracy and reduced bias in estimating GFR using the CKD-EPI equation at higher range may provide better definition for managing metabolic syndrome in population at increased risk for CKD and facilitate more appropriate risk stratification.restrictio