Tsai Yi-Chun, Chiu Yi-Wen, Tsai Jer-Chia, Kuo Hung-Tien, Hung Chi-Chih, Hwang Shang-Jyh, Chen Tzu-Hui, Kuo Mei-Chuan, Chen Hung-Chun
Graduate Institute of Clinical Medicine and Division of Nephrology and Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan;
Division of Nephrology and Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan;
Clin J Am Soc Nephrol. 2015 Jan 7;10(1):39-46. doi: 10.2215/CJN.03610414. Epub 2014 Dec 15.
Fluid overload is a common characteristic associated with renal progression in CKD. Additionally, fluid overload is an independent predictor of all-cause or cardiovascular mortality in patients on dialysis, but its influence on patients not on dialysis is uncertain. The aim of the study was to assess the relationship between the severity of fluid status and clinical outcomes in an advanced CKD cohort.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In total, 478 predialysis patients with stages 4 and 5 CKD in the integrated CKD care program were enrolled from January of 2011 to December of 2011 and followed-up until August of 2013. The clinical outcomes included cardiovascular morbidity and all-cause mortality. The relative hydration status (overhydration/extracellular water) was used as the presentation of the severity of fluid status and measured using a body composition monitor. Overhydration/extracellular water >7% was defined as fluid overload.
Over a median follow-up period of 23.2 (12.6-26.4) months, 66 (13.8%) patients reached all-cause mortality or cardiovascular morbidity. The adjusted hazard ratio of the combined outcome of all-cause mortality or cardiovascular morbidity for every 1% higher overhydration/extracellular water was 1.08 (95% confidence interval, 1.04 to 1.12; P<0.001). The adjusted overhydration/extracellular water for the combined outcome of all-cause mortality or cardiovascular morbidity in participants with overhydration/extracellular water ≥7% compared with those with overhydration/extracellular water <7% was 1.93 (95% confidence interval, 1.01 to 3.69; P=0.04). In subgroup analysis, higher overhydration/extracellular water was consistently associated with increased risk for the combined outcome independent of diabetes, cardiovascular disease, and serum albumin. There was no significant interaction between all subgroups.
These findings suggest that fluid overload is an independent risk factor of the combined outcome of all-cause mortality or cardiovascular morbidity in patients with advanced CKD.
液体超负荷是慢性肾脏病（CKD）肾脏进展的常见特征。此外，液体超负荷是透析患者全因或心血管死亡的独立预测因素，但其对未透析患者的影响尚不确定。本研究旨在评估晚期CKD队列中液体状态严重程度与临床结局之间的关系。
设计、地点、参与者及测量方法：2011年1月至2011年12月，在综合CKD护理项目中总共纳入了478例4期和5期CKD的透析前患者，并随访至2013年8月。临床结局包括心血管疾病发病率和全因死亡率。相对水合状态（水过多/细胞外液）用于表示液体状态的严重程度，并使用身体成分监测仪进行测量。水过多/细胞外液>7%被定义为液体超负荷。
在中位随访期23.2（12.6 - 26.4）个月内，66例（13.8%）患者出现全因死亡或心血管疾病发病。水过多/细胞外液每升高1%，全因死亡或心血管疾病发病联合结局的校正风险比为1.08（95%置信区间，1.04至1.12；P<0.001）。与水过多/细胞外液<7%的参与者相比，水过多/细胞外液≥7%的参与者全因死亡或心血管疾病发病联合结局的校正水过多/细胞外液为1.93（95%置信区间，1.01至3.69；P = 0.04）。在亚组分析中，较高的水过多/细胞外液始终与联合结局风险增加相关，且独立于糖尿病、心血管疾病和血清白蛋白。所有亚组之间均无显著交互作用。
这些发现表明，液体超负荷是晚期CKD患者全因死亡或心血管疾病发病联合结局的独立危险因素。
