Nuffield Department of Primary Care Health Sciences, Oxford.
Oxford University Hospitals Biochemistry Department, John Radcliffe Hospital, Oxford.
Br J Gen Pract. 2018 Aug;68(673):e524-e530. doi: 10.3399/bjgp18X697937. Epub 2018 Jul 2.
Chronic kidney disease (CKD) is diagnosed using the estimated glomerular filtration rate (eGFR) and the urinary albumin:creatinine ratio (ACR). The eGFR is calculated from serum creatinine levels using the Modification of Diet in Renal Disease (MDRD) or Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations.
To compare the performance of one versus two eGFR/ACR measurements, and the impact of equation choice, on CKD diagnosis and classification.
Cohort study in primary care in the Thames Valley region of the UK.
Data were from 485 participants aged >60 years in the Oxford Renal Cohort Study with at least two eGFR tests. The proportion of study participants diagnosed and classified into different CKD stages using one and two positive tests were compared. Prevalence of CKD diagnosis and classification by CKD stage were compared when eGFR was calculated using MDRD and CKD-EPI equations.
Participants included in the analysis had a mean age of 72.1 (±6.8) years and 57.0% were female. Use of a single screening test overestimated the proportion of people with CKD by around 25% no matter which equation was used, compared with the use of two tests. The mean eGFR was 1.4 ml/min/1.73 m (95% CI = 1.1 to 1.6) higher using the CKD-EPI equation compared with the MDRD equation. More patients were diagnosed with CKD when using the MDRD equation, compared with the CKD-EPI equation, once (64% versus 63%, respectively) and twice (39% versus 38%, respectively), and 16 individuals, all of who had CKD stages 2 or 3A with MDRD, were reclassified as having a normal urinary ACR when using the CKD-EPI equation.
Current guidance to use two eGFR measures to diagnose CKD remains appropriate in an older primary care population to avoid overdiagnosis. A change from MDRD to CKD-EPI equation could result in one in 12 patients with a CKD diagnosis with MDRD no longer having a diagnosis of CKD.
慢性肾脏病（CKD）的诊断使用估算肾小球滤过率（eGFR）和尿白蛋白/肌酐比值（ACR）。eGFR 是根据血清肌酐水平使用肾脏病膳食改良试验（MDRD）或慢性肾脏病流行病学合作研究（CKD-EPI）公式计算得出的。
比较一次与两次 eGFR/ACR 测量的性能，以及方程选择对 CKD 诊断和分类的影响。
英国泰晤士河谷地区初级保健中的队列研究。
数据来自牛津肾脏队列研究中至少有两次 eGFR 检测的 485 名年龄>60 岁的参与者。比较一次和两次阳性检测对 CKD 诊断和分类的研究参与者比例。当使用 MDRD 和 CKD-EPI 公式计算 eGFR 时，比较 CKD 诊断和分类的患病率和 CKD 分期。
纳入分析的参与者平均年龄为 72.1（±6.8）岁，57.0%为女性。无论使用哪种方程，单次筛查试验都会使 CKD 患者的比例高估约 25%，而使用两次试验则不会。使用 CKD-EPI 方程的平均 eGFR 比 MDRD 方程高 1.4 ml/min/1.73 m（95%CI = 1.1 至 1.6）。与 CKD-EPI 方程相比，使用 MDRD 方程时，更多的患者被诊断为 CKD，一次为 64%，两次为 39%，而 16 名患者均患有 MDRD 定义的 CKD 2 或 3A 期，改用 CKD-EPI 方程后，均被重新归类为尿 ACR 正常。
目前，使用两次 eGFR 测量来诊断 CKD 的指南仍然适用于老年初级保健人群，以避免过度诊断。从 MDRD 改为 CKD-EPI 方程可能会导致每 12 名患有 CKD 诊断的患者中就有 1 名患者不再患有 CKD 诊断。
