Department of Nephrology, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo, 162-3655, Japan.
Department of Nephrology, Tokyo Medical and Dental University, Tokyo, Japan.
Clin Exp Nephrol. 2020 May;24(5):458-464. doi: 10.1007/s10157-019-01844-0. Epub 2020 Jan 27.
Serum anion gap (AG) has recently been proven to represent a biomarker for predicting prognosis in patients with end-stage renal disease (ESRD). However, whether change in AG (ΔAG) at the time of starting hemodialysis predicts mortality after starting hemodialysis in elderly patients with ESRD remains unknown.
This retrospective cohort investigated the association between ΔAG and mortality after starting hemodialysis in the elderly. The cohort comprised patients ≥ 75 years old who started hemodialysis for ESRD at National Center for Global Health and Medicine between 2010 and 2017 and at Yokosuka Kyosai Hospital between 2007 and 2011. Patients were stratified into three groups (G1-3) based on ΔAG, calculated according to the equation: ΔAG = sodium - (chloride + bicarbonate) - 12. The primary outcome was death within 1 year of starting hemodialysis. Data were analyzed using Cox proportional hazard models with adjustments for baseline characteristics.
We enrolled 254 patients (59% male). Median ΔAG was 2.6 (G1: > 3, n = 111; G2: 0-3, n = 103; G3: < 0, n = 40). The primary outcome was observed in 43 patients. Hazard ratios (HRs) were significantly higher for G1 and G3 than for G2 (G1: HR 2.47, 95% confidence interval 1.13-5.37; G3: HR 3.86, 95% confidence interval 1.62-9.16). Adjusted HRs (aHRs) were significantly higher for G1 and G3 than for G2 (G1: aHR 3.06, 95% confidence interval 1.23-7.62; G3: aHR 3.12, 95% confidence interval 1.10-8.78).
A J-curve phenomenon is evident between ΔAG and early mortality after starting hemodialysis in the elderly.
血清阴离子间隙（AG）最近已被证明是预测终末期肾病（ESRD）患者预后的生物标志物。然而，在开始血液透析时 AG 的变化（ΔAG）是否可以预测老年 ESRD 患者开始血液透析后的死亡率尚不清楚。
本回顾性队列研究调查了开始血液透析时 ΔAG 与老年患者血液透析后死亡率之间的关系。该队列包括 2010 年至 2017 年在国立全球卫生与医学中心和 2007 年至 2011 年在横须贺恭赛医院开始血液透析治疗 ESRD 的年龄≥75 岁的患者。根据以下公式计算ΔAG 并将患者分为三组（G1-3）：ΔAG=钠-（氯+碳酸氢盐）-12。主要结局是开始血液透析后 1 年内死亡。使用 Cox 比例风险模型分析数据，并根据基线特征进行调整。
共纳入 254 名患者（59%为男性）。中位 ΔAG 为 2.6（G1：>3，n=111；G2：0-3，n=103；G3：<0，n=40）。主要结局在 43 名患者中观察到。与 G2 相比，G1 和 G3 的危险比（HR）显著更高（G1：HR 2.47，95%置信区间 1.13-5.37；G3：HR 3.86，95%置信区间 1.62-9.16）。与 G2 相比，G1 和 G3 的调整后 HR（aHR）显著更高（G1：aHR 3.06，95%置信区间 1.23-7.62；G3：aHR 3.12，95%置信区间 1.10-8.78）。
在开始血液透析时，ΔAG 与老年患者早期死亡率之间存在 J 型曲线现象。
