Department of Medicine, V.A. Medical Center 3495 Bailey Ave., Buffalo, New York 14215, USA.
BMC Nephrol. 2012 Jan 20;13:4. doi: 10.1186/1471-2369-13-4.
Black individuals are far more likely than white individuals to develop end stage renal disease (ESRD). However, earlier stages of chronic kidney disease (CKD) have been reported to be less prevalent among blacks. This disparity remains poorly understood. The objective of this study was to evaluate whether the lower prevalence of CKD among blacks in early stages of CKD might be due in part to an inability of the MDRD equation to accurately determine early stages of CKD in both the black and white population.
We conducted a retrospective cohort study of 97, 451 patients seen in primary care clinic in Veterans Integrated Service Network 2 (VISN 2) over a 7 year period to determine the prevalence of CKD using both the Modification of Diet in Renal Disease (MDRD) Study equation and the more recently developed CKD Epidemiology Collaboration (CKD-EPI) equation. Demographic data, comorbid conditions, prescription of medications, and laboratory data were recorded. Logistic regression and quantile regression models were used to compare the prevalence of estimated glomerular filtration rate (eGFR) categories between black and white individuals.
The overall prevalence of CKD was lower when the CKD-EPI equation was used. Prevalence of CKD in whites was 53.2% by MDRD and 48.4% by CKD-EPI, versus 34.1% by MDRD and 34.5% by CKD-EPI in blacks. The cumulative logistic regression and quantile regression showed that when eGFR was calculated by the EPI method, blacks were as likely to present with an eGFR value less than 60 mL/min/1.73 m2 as whites. Using the CKD-EPI equation, blacks were more likely than white individuals to have stage 3b, 4 and 5 CKD. Using the MDRD method, the prevalence in blacks was only higher than in whites for stage 4 and 5 CKD. Similar results were obtained when the analysis was confined to patients over 65 years of age.
The MDRD equation overestimates the prevalence of CKD among whites and underestimates the prevalence of CKD in blacks compared to the CKD-EPI equation.
黑人比白人更容易发展为终末期肾病（ESRD）。然而，据报道，黑人慢性肾脏病（CKD）的早期阶段发病率较低。这种差异仍未得到很好的理解。本研究的目的是评估在 CKD 的早期阶段，黑人 CKD 的患病率较低是否部分归因于 MDRD 方程无法准确确定黑人和白人人群的早期 CKD。
我们对退伍军人综合服务网络 2（VISN 2）的初级保健诊所 97451 名患者进行了回顾性队列研究，在 7 年期间使用改良肾脏病饮食研究（MDRD）方程和最近开发的慢性肾脏病流行病学合作（CKD-EPI）方程来确定 CKD 的患病率。记录了人口统计学数据、合并症、药物处方和实验室数据。使用逻辑回归和分位数回归模型比较黑人和白人个体之间估计肾小球滤过率（eGFR）类别之间的患病率。
当使用 CKD-EPI 方程时，总体 CKD 患病率较低。白人的 MDRD 患病率为 53.2%，CKD-EPI 患病率为 48.4%，而黑人的 MDRD 患病率为 34.1%，CKD-EPI 患病率为 34.5%。累积逻辑回归和分位数回归表明，当使用 EPI 方法计算 eGFR 时，黑人与白人一样有可能出现 eGFR 值低于 60 mL/min/1.73 m2。使用 CKD-EPI 方程，黑人比白人更有可能患有 3b、4 和 5 期 CKD。使用 MDRD 方法，黑人的患病率仅高于白人 4 期和 5 期 CKD。当分析仅限于 65 岁以上的患者时，也得到了类似的结果。
与 CKD-EPI 方程相比，MDRD 方程高估了白人 CKD 的患病率，低估了黑人 CKD 的患病率。
