Differential estimation of CKD using creatinine- versus cystatin C-based estimating equations by category of body mass index.

作者信息

Vupputuri Suma, Fox Caroline S, Coresh Josef, Woodward Mark, Muntner Paul

机构信息

Center for Health Research, Kaiser Permanente Georgia, Atlanta, GA 30305, USA.

出版信息

Am J Kidney Dis. 2009 Jun;53(6):993-1001. doi: 10.1053/j.ajkd.2008.12.043. Epub 2009 Apr 25.

DOI:10.1053/j.ajkd.2008.12.043

PMID:19394726

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3028436/

Abstract

BACKGROUND

Adiposity is associated with cystatin C. Cystatin C-based glomerular filtration rate (GFR) equations may result in overestimation of chronic kidney disease (CKD) prevalence at greater body mass index (BMI) levels.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS: 6,709 US adult Third National Health and Nutrition Examination Survey participants.

FACTOR

BMI.

OUTCOME

Absolute percentage of difference in prevalence of stage 3 or 4 CKD between creatinine- and cystatin C-based estimating equations by level of BMI.

MEASUREMENTS

Normal weight, overweight, and obesity were defined as BMI of 18.5 to less than 25.0, 25 to less than 30.0, and 30 kg/m(2) or greater, respectively. Stage 3 or 4 CKD (estimated glomerular filtration rate [eGFR], 15 to 59 mL/min/1.73 m(2)) was defined using the 4-variable creatinine-based Modification of Diet in Renal Disease Study equation (eGFR(MDRD)); cystatin C level, age, sex, and race equation (eGFR(CysC,age,sex,race)); cystatin C-only equation (eGFR(CysC)); cystatin C level of 1.12 mg/L or greater (increased cystatin C); and an equation incorporating serum creatinine level, cystatin C level, age, sex, and race (eGFR(Cr,CysC,age,sex,race)).

RESULTS

Differences in stage 3 or 4 CKD prevalence estimates between eGFR(CysC,age,sex,race), eGFR(CysC), and increased cystatin C, separately, and eGFR(MDRD) were greater at higher BMI levels. Specifically, compared with estimates derived using eGFR(MDRD) for normal-weight, overweight, and obese participants, estimated prevalences of stage 3 or 4 CKD were 2.1%, 3.0%, and 6.5% greater when estimated by using eGFR(CysC,age,sex,race) (P trend = 0.005); 0.1%, 0.6%, and 2.2% greater for eGFR(CysC) (P trend = 0.03); 2.9%, 5.2%, and 9.5% greater for increased cystatin C (P trend < 0.001); and -0.1%, -0.4%, and 0.0% greater for eGFR(Cr,CysC,age,sex,race), respectively (P trend = 0.7).