Epidemiological analysis on chronic kidney disease in Asian population after standardization of creatinine measurement

对于慢性肾脏病（CKD）的诊断和分期，通过肾小球滤过率（GFR）评估肾功能至关重要。GFR的估计值可通过血清肌酐（Cr）、年龄和性别来计算，因此通过可靠的Cr值来评估GFR非常重要。在这项在韩国、台湾、泰国和日本开展的国际合作研究中，我们分析了合作中心采用Jaffe方法测量的Cr值，并对日本中心实验室的Cr值进行了标准化。台湾地区的Cr值与日本标准值几乎相同，而韩国的Cr值约为0。亚洲人MDRD方程的种族系数存在争议，尽管与白人相比，亚洲人的遗传、饮食和生活方式相似。在这项研究中，我们测量了200名韩国人，200名台湾人和60名泰国患者的菊糖清除率，并比较了日本GFR和MDRD方程在各个种族中的准确性。日本GFR方程式在韩国显示较佳的准确性，但在台湾则不然。我们以标准化的Cr值和可靠的日本GFR方程为基础，对爱知县约10万名健康检查对象进行了CKD患病率分析。蛋白尿阳性率在爱知县高于全国调查，在男性和女性，并在所有年龄组。GFR低于60 mL/min/l的患病率。73 m2是8。爱知县为6%，低于10.在全国调查中，6%，可证明是由于爱知县不同的生命统计。

For Chronic Kidney Disease(CKD) diagnosis and staging, is essential to evaluate kidney function by glomerular filtration rate(GFR). Estimated GFR could be calculated by serum creatinine(Cr), age and gender, therefore it is important to evaluate GFR by reliable Cr values. In this international collaborative study in Korea, Taiwan, Thailand and Japan, we analyzed Cr values measured in collaborative centers by Jaffe method and standardized Cr values in a central laboratory in Japan. Cr values in Taiwan were almost identical to Japanese standardized one, while those in Korea exhibited approximately 0. 2mg/dL higher values, which revealed a significance of standardization of Cr measurement methods.There is a controversy in ethnic coefficient for MDRD equation among Asians, regardless of similar genetics, food and lifestyle compared to Caucasian. In this study, we measured GFR by inulin clearance with an uniform protocol in 200 Korean, 200 Taiwanese and 60 Thai patients, and compare accuracies of Japanese GFR and MDRD equations in individual ethnics. Japanese GFR equations revealed better accuracy in Korean but not in Taiwanese. Cr excretion rate, a marker of body muscle mass, was greater in Taiwanese compared to Japanese and Korean, which suggest that different body muscle mass plays a major role in different ethnic coefficient.Based on standardized Cr values and reliable Japanese GFR equation, we conducted CKD prevalence analysis among approximately 100, 000 health-check subjects in Aichi prefecture. Positive rates of proteinuria were greater in Aichi than in the national survey, in both male and female, and in all age groups. Prevalence of low GFR less than 60 mL/min/1. 73m2 was 8. 6% in Aichi prefecture, which was smaller than 10. 6% in the national survey, provably due to different vital statics in Aichi prefecture.