title: Comparison of CKD-EPI Cystatin C and Creatinine Glomerular Filtration Rate Estimation Equations in Asian Indians.
abstract: Background. Chronic kidney disease (CKD) is identified in the general population using estimated glomerular filtration rates (eGFR) calculated from a serum creatinine-based equation, the chronic kidney disease-epidemiology collaboration (CKD-EPI) equation. Using serum cystatin C in combination may improve eGFR accuracy. We evaluated the new CKD-EPI equations incorporating cystatin C in a population of Asian Indians in classifying CKD across body mass index, diabetes, and hypertension status. Methods. We retrieved standardized serum creatinine and serum cystatin C data from a cohort of 2877 Asian Indians aged 40-80 years from the Singapore Indian Eye Study and calculated eGFR (in mL/min/1.73 m(2)) with the new CKD-EPI equations and serum creatinine only equation. Results. The creatinine only equation mean eGFR (88 ± 17) was similar to using spline Log cystatin C (88 ± 22). The lowest mean eGFR (81 ± 21) was obtained with the spline Log cystatin C-age, sex, and weight equation. The creatinine only equation had the fewest participants (7.1%) with eGFR <60 and spline Log cystatin C-age, sex, and weight equation had the most (16.1%). Conclusions. Using serum cystatin C resulted in widely varying eGFR which significantly affected the classification of chronic kidney disease.
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, Level 10 NUHS Tower Block, Singapore 119228.
authors.forename: Boon Wee
authors.initials: BW
authors.lastname: Teo
authors.affiliation: Singapore Eye Research Institute, c/o Singapore National Eye Center, 11 Third Hospital Avenue, Singapore 168751 ; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore 119228 ; Office of Clinical Sciences, Duke-NUS Graduate Medical School, National University of Singapore, 8 College Road, Singapore 169857.
authors.forename: Charumathi
authors.initials: C
authors.lastname: Sabanayagam
authors.affiliation: Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore 119228.
authors.forename: Jiemin
authors.initials: J
authors.lastname: Liao
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, Level 10 NUHS Tower Block, Singapore 119228.
authors.forename: Qi Chun
authors.initials: QC
authors.lastname: Toh
authors.affiliation: Department of Laboratory Medicine, National University Hospital and National University Health System, 5 Lower Kent Ridge Road, Singapore 119074.
authors.forename: Sharon
authors.initials: S
authors.lastname: Saw
authors.affiliation: Singapore Eye Research Institute, c/o Singapore National Eye Center, 11 Third Hospital Avenue, Singapore 168751 ; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, NUHS Tower Block, Singapore 119228 ; Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Graduate Medical School, National University of Singapore, 8 College Road, Singapore 169857.
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
authors.affiliation: Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, 1E Kent Ridge Road, Level 10 NUHS Tower Block, Singapore 119228.
authors.forename: Sunil
authors.initials: S
authors.lastname: Sethi