Wagner Sandra, Merkling Thomas, Metzger Marie, Bankir Lise, Laville Maurice, Frimat Luc, Combe Christian, Jacquelinet Christian, Fouque Denis, Massy Ziad A, Stengel Bénédicte
Université de Lorraine, INSERM CIC 1433, Nancy CHRU, Inserm U1116, FCRIN INI-CRCT, Nancy, France.
Centre de recherche en Epidémiologie et Santé des Populations (CESP), INSERM U1018, Université Paris-Saclay, Université Versailles Saint Quentin, Villejuif, France.
Nephrol Dial Transplant. 2022 Mar 25;37(4):730-739. doi: 10.1093/ndt/gfab036.
Optimal daily water intake to prevent chronic kidney disease (CKD) progression is unknown. Taking the kidney's urine-concentrating ability into account, we studied the relation of kidney outcomes in patients with CKD to total and plain water intake and urine volume.
Including 1265 CKD patients [median age 69 years; mean estimated glomerular filtration rate (eGFR) 32 mL/min/1.73 m2] from the Chronic Kidney Disease-Renal Epidemiology and Information Network cohort (2013-19), we assessed fluid intake at baseline interviews, collected 24-h urine volumes and estimated urine osmolarity (eUosm). Using Cox and then linear mixed models, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for kidney failure and eGFR decline associated with hydration markers, adjusting for CKD progression risk factors and eUosm.
Patients' median daily intake was 2.0 L [interquartile range (IQR) 1.6-2.6] for total water and 1.5 L (1-1.7) for plain water, median urine volume was 1.9 L/24 h (IQR 1.6-2.4) and mean eUosm was 374 ± 104 mosm/L. Neither total water intake nor urine volume was associated with either kidney outcome. Kidney failure risk increased significantly with decreasing eUosm ˂292 mosm/L. Adjusted HRs (95% CIs) for kidney failure associated with plain water intake were 1.88 (1.02-3.47), 1.59 (1.06-2.38), 1.76 (0.95-3.24) and 1.55 (1.03-2.32) in patients drinking <0.5, 0.5-1.0, 1.5-2.0 and >2.0 L/day compared with those drinking 1.0-1.5 L/day. High plain water intake was also significantly associated with faster eGFR decline.
In patients with CKD, the relation between plain water intake and progression to kidney failure appears to be U-shaped. Both low and high intake may not be beneficial in CKD.
预防慢性肾脏病（CKD）进展的最佳每日饮水量尚不清楚。考虑到肾脏的尿液浓缩能力，我们研究了CKD患者的肾脏结局与总饮水量、白开水摄入量和尿量之间的关系。
纳入慢性肾脏病-肾脏流行病学和信息网络队列（2013 - 2019年）中的1265例CKD患者[中位年龄69岁；平均估计肾小球滤过率（eGFR）为32 mL/min/1.73 m²]，我们在基线访谈时评估液体摄入量，收集24小时尿量并估算尿渗透压（eUosm）。使用Cox模型，然后是线性混合模型，我们估计了与水化标志物相关的肾衰竭和eGFR下降的风险比（HRs）及95%置信区间（CIs），并对CKD进展风险因素和eUosm进行了校正。
患者的总饮水量中位数为2.0 L[四分位间距（IQR）1.6 - 2.6]，白开水摄入量中位数为1.5 L（1 - 1.7），尿量中位数为1.9 L/24小时（IQR 1.6 - 2.4），平均eUosm为374 ± 104 mOsm/L。总饮水量和尿量均与任何一种肾脏结局均无关联。当eUosm < 292 mOsm/L时，肾衰竭风险随其降低而显著增加。与每日饮用1.0 - 1.5 L白开水的患者相比，每日饮用<0.5 L、0.5 - 1.0 L、1.5 - 2.0 L和>2.0 L的患者，校正后的肾衰竭HRs（95% CIs）分别为1.88（1.02 - 3.47）、1.59（1.06 - 2.38）、1.76（0.95 - 3.24）和1.55（1.03 - 2.32）。高白开水摄入量也与eGFR更快下降显著相关。
在CKD患者中，白开水摄入量与肾衰竭进展之间的关系似乎呈U形。低摄入量和高摄入量对CKD可能均无益处。
