title: Is the new GFR equation using inulin clearance a more accurate method for Asian patients?
abstract: Recently, a new glomerular filtration rate (GFR) equation for the Japanese population was proposed using measured inulin clearance. To expand its applicability to other Asian populations, we performed a comparative study in the Korean population. Inulin clearance was measured in 166 patients from seven participating medical centers in Korea. Patient's sera and urine were collected, and baseline clinical characteristics were measured to provide an estimated GFR (eGFR) by the Japanese GFR equation using inulin clearance (Japanese-GFR equation), the Modification of Diet in Renal Disease (MDRD) study equation, and the Chronic Kidney Disease - Epidemiology Collaboration (CKD-EPI) equation. We compared the results to determine which equation best estimated the measured GFR (mGFR). Accuracy (95% CI) within 30% of mGFR by the Japanese-GFR equation, the CKD-EPI equation and the MDRD study equation were 66 (58 - 72), 51 (43 - 58), and 55 (47 - 62)%, respectively. Bias (mGFR minus eGFR) were 3.4 ± 22.4, -12.0 ± 22.1, and -9.7 ± 23.8 mL/min/1.73 m2, respectively. The accuracy of the Japanese-GFR equation was significantly better than MDRD study equation in subjects with mGFR < 60 mL/min/1.73 m2 and in total subjects. The bias of the Japanese-GFR equation was significantly smaller compared with other two equations in total subjects. The Japanese-GFR equation has a higher accuracy with less bias than the other equations in estimating GFR in Korean populations. Further studies are required to determine if the current Japanese-GFR equation could represent the standard eGFR for other Asian populations.
authors.affiliation: Department of Nephrology, Severance Hospital, Yonsei University College of Medicine, Seoul, Nephrology Division, Department of Internal Medicine, National Health Institute Corporation, Ilsan Hospital, Goyang, Geonggido, Nephrology Division, Department of Internal Medicine, Kangnam Severance Hospital, Seoul, Nephrology Division, Department of Internal Medicine, Yonsei University Wonju Christian Hospital, Wonju, Kangwon, Nephrology Division, Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Nephrology Division Department of Internal Medicine, Inje University Busan Hospital, Busan, Nephrology Division, Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea, Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Nakayamadera Imai Clinic, Takarazuka, Hyogo, Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine, Osaka, and Department of Nephrology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Beom Seok
authors.initials: BS
authors.lastname: Kim
authors.forename: Yong Kyu
authors.initials: YK
authors.lastname: Lee
authors.forename: Hoon Young
authors.initials: HY
authors.lastname: Choi
authors.forename: Seung Ok
authors.initials: SO
authors.lastname: Choi
authors.forename: Sug Kyun
authors.initials: SK
authors.lastname: Shin
authors.forename: Sung Kyu
authors.initials: SK
authors.lastname: Ha
authors.forename: Kang Wook
authors.initials: KW
authors.lastname: Lee
authors.forename: Yang Wook
authors.initials: YW
authors.lastname: Kim
authors.forename: Yong Lim
authors.initials: YL
authors.lastname: Kim
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Yasuda
authors.forename: Enyu
authors.initials: E
authors.lastname: Imai
authors.forename: Masaru
authors.initials: M
authors.lastname: Horio
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tomino
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsuo
authors.forename: Ho Yung
authors.initials: HY
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000419:Albuminuria / Q000378:metabolism; D000465:Algorithms; D044466:Asian People; D015982:Bias; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007444:Inulin / Q000097:blood / Q000378:metabolism* / Q000652:urine; D007564:Japan; D007677:Kidney Function Tests / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000652:urine; D056910:Republic of Korea / Q000208:ethnology; D012709:Serum Albumin / Q000032:analysis; D055815:Young Adult
chemical_list: D012709:Serum Albumin; D007444:Inulin; D003404:Creatinine