Nephrology Department, Hospital Universitario Puerta de Hierro, Madrid, Spain.
BMC Nephrol. 2013 Jan 7;14:2. doi: 10.1186/1471-2369-14-2.
Anemia is a common condition in CKD that has been identified as a cardiovascular (CV) risk factor in end-stage renal disease, constituting a predictor of low survival. The aim of this study was to define the onset of anemia of renal origin and its association with the evolution of kidney disease and clinical outcomes in stage 3 CKD (CKD-3).
This epidemiological, prospective, multicenter, 3-year study included 439 CKD-3 patients. The origin of nephropathy and comorbidity (Charlson score: 3.2) were recorded. The clinical characteristics of patients that developed anemia according to EBPG guidelines were compared with those that did not, followed by multivariate logistic regression, Kaplan-Meier curves and ROC curves to investigate factors associated with the development of renal anemia.
During the 36-month follow-up period, 50% reached CKD-4 or 5, and approximately 35% were diagnosed with anemia (85% of renal origin). The probability of developing renal anemia was 0.12, 0.20 and 0.25 at 1, 2 and 3 years, respectively. Patients that developed anemia were mainly men (72% anemic vs. 69% non-anemic). The mean age was 68 vs. 65.5 years and baseline proteinuria was 0.94 vs. 0.62 g/24h (anemic vs. non anemic, respectively). Baseline MDRD values were 36 vs. 40 mL/min and albumin 4.1 vs. 4.3 g/dL; reduction in MDRD was greater in those that developed anemia (6.8 vs. 1.6 mL/min/1.73 m2/3 years). These patients progressed earlier to CKD-4 or 5 (18 vs. 28 months), with a higher proportion of hospitalizations (31 vs. 16%), major CV events (16 vs. 7%), and higher mortality (10 vs. 6.6%) than those without anemia. Multivariate logistic regression indicated a significant association between baseline hemoglobin (OR=0.35; 95% CI: 0.24-0.28), glomerular filtration rate (OR=0.96; 95% CI: 0.93-0.99), female (OR=0.19; 95% CI: 0.10-0.40) and the development of renal anemia.
Renal anemia is associated with a more rapid evolution to CKD-4, and a higher risk of CV events and hospitalization in non-dialysis-dependent CKD patients. This suggests that special attention should be paid to anemic CKD-3 patients.
贫血是 CKD 的常见病症，已被确定为终末期肾脏病的心血管（CV）危险因素，构成低生存率的预测因素。本研究的目的是确定肾性贫血的发病，并探讨其与 3 期 CKD（CKD-3）中肾脏疾病的进展和临床结局的关系。
本项流行病学、前瞻性、多中心、3 年研究纳入了 439 例 CKD-3 患者。记录了肾病和合并症（Charlson 评分：3.2）的发病原因。根据 EBPG 指南，比较了出现贫血的患者和未出现贫血的患者的临床特征，然后进行多变量逻辑回归、Kaplan-Meier 曲线和 ROC 曲线分析，以探讨与肾性贫血发展相关的因素。
在 36 个月的随访期间，50%的患者进展到 CKD-4 或 5 期，约 35%的患者被诊断为贫血（85%为肾性贫血）。在 1、2 和 3 年时，发生肾性贫血的概率分别为 0.12、0.20 和 0.25。发生贫血的患者主要为男性（贫血患者中为 72%，非贫血患者中为 69%）。平均年龄为 68 岁 vs. 65.5 岁，基线蛋白尿为 0.94 克/24 小时 vs. 0.62 克/24 小时（分别为贫血患者和非贫血患者）。基线 MDRD 值为 36 毫升/分钟 vs. 40 毫升/分钟，白蛋白为 4.1 克/天 vs. 4.3 克/天；发生贫血的患者 MDRD 值下降幅度更大（6.8 毫升/分钟 vs. 1.6 毫升/分钟/1.73 平方米/3 年）。这些患者更早地进展到 CKD-4 或 5 期（18 个月 vs. 28 个月），住院率更高（31% vs. 16%），主要 CV 事件（16% vs. 7%）和死亡率更高（10% vs. 6.6%）。多变量逻辑回归表明，基线血红蛋白（OR=0.35；95%CI：0.24-0.28）、肾小球滤过率（OR=0.96；95%CI：0.93-0.99）、女性（OR=0.19；95%CI：0.10-0.40）与肾性贫血的发生有显著相关性。
肾性贫血与 CKD-4 更快进展以及非透析依赖的 CKD 患者更高的 CV 事件和住院风险相关。这表明，应特别关注贫血性 CKD-3 患者。
