Rhee Connie M, Ravel Vanessa A, Ayus Juan Carlos, Sim John J, Streja Elani, Mehrotra Rajnish, Amin Alpesh N, Nguyen Danh V, Brunelli Steven M, Kovesdy Csaba P, Kalantar-Zadeh Kamyar
Harold Simmons Center for Chronic Disease Research and Epidemiology, University of California Irvine, Orange, CA, USA.
Renal Consultants of Houston, Houston, TX, USA.
Nephrol Dial Transplant. 2016 Jun;31(6):992-1001. doi: 10.1093/ndt/gfv341. Epub 2015 Sep 25.
A consistent association between low serum sodium measured at a single-point-in-time (baseline sodium) and higher mortality has been observed in hemodialysis patients. We hypothesized that both low and high time-varying sodium levels (sodium levels updated at quarterly intervals as a proxy of short-term exposure) are independently associated with higher death risk in hemodialysis patients.
We examined the association of baseline and time-varying pre-dialysis serum sodium levels with all-cause mortality among adult incident hemodialysis patients receiving care from a large national dialysis organization during January 2007-December 2011. Hazard ratios were estimated using multivariable Cox models accounting for case-mix+laboratory covariates and incrementally adjusted for inter-dialytic weight gain, blood urea nitrogen and glucose.
Among 27 180 patients, a total of 7562 deaths were observed during 46 194 patient-years of follow-up. Median (IQR) at-risk time was 1.4 (0.6, 2.5) years. In baseline analyses adjusted for case-mix+laboratory results, sodium levels <138 mEq/L were associated with incrementally higher mortality risk, while the association of sodium levels ≥140 mEq/L with lower mortality reached statistical significance only for the highest level of pre-dialysis sodium (reference: 138-<140 mEq/L). In time-varying analyses, we observed a U-shaped association between sodium and mortality such that sodium levels <138 and ≥144 mEq/L were associated with higher mortality risk. Similar patterns were observed in models incrementally adjusted for inter-dialytic weight gain, blood urea nitrogen and glucose.
We observed a U-shaped association of time-varying pre-dialysis serum sodium and all-cause mortality in hemodialysis patients, suggesting that both hypo- and hypernatremia carry short-term risk in this population.
在血液透析患者中，已观察到单点时间测量的低血清钠（基线钠）与较高死亡率之间存在一致关联。我们假设，血液透析患者中，低和高的随时间变化的钠水平（每季度更新一次的钠水平作为短期暴露的替代指标）均与较高的死亡风险独立相关。
我们研究了2007年1月至2011年12月期间，在一家大型全国性透析机构接受治疗的成年初发血液透析患者中，基线和随时间变化的透析前血清钠水平与全因死亡率之间的关联。使用多变量Cox模型估计风险比，该模型考虑了病例组合+实验室协变量，并逐步调整了透析间期体重增加、血尿素氮和血糖。
在27180例患者中，在46194患者-年的随访期间共观察到7562例死亡。中位（IQR）风险时间为1.4（0.6，2.5）年。在根据病例组合+实验室结果进行调整的基线分析中，钠水平<138 mEq/L与死亡率风险逐步升高相关，而钠水平≥140 mEq/L与较低死亡率的关联仅在透析前钠的最高水平时达到统计学显著性（参考：138-<140 mEq/L）。在随时间变化的分析中，我们观察到钠与死亡率之间呈U形关联，即钠水平<138和≥144 mEq/L与较高的死亡率风险相关。在逐步调整透析间期体重增加、血尿素氮和血糖的模型中也观察到类似模式。
我们观察到血液透析患者中，随时间变化的透析前血清钠与全因死亡率呈U形关联，这表明低钠血症和高钠血症在该人群中均具有短期风险。
