Hiki Masaru, Kasai Takatoshi, Yatsu Shoichiro, Murata Azusa, Matsumoto Hiroki, Kato Takao, Suda Shoko, Miyazaki Tetsuro, Takagi Atsutoshi, Daida Hiroyuki
Department of Cardiovascular Medicine, Juntendo University School of Medicine.
Cardiovascular Respiratory Sleep Medicine, Juntendo University Graduate School of Medicine.
Int Heart J. 2018 Sep 26;59(5):1052-1058. doi: 10.1536/ihj.17-524. Epub 2018 Aug 11.
Although hyponatremia during hospitalization for acute decompensated heart failure (ADHF) is reportedly related with poor prognosis, the available data regarding the impact of serum sodium level within the low-normal range at admission on clinical events in patients with ADHF is limited.We studied eligible patients admitted to our institution in 2007-2011. All the patients were categorized into 3 groups according to the admission serum sodium levels of < 135 mmol/L (hyponatremia), ≥ 135 and < 140 mmol/L (low-normal range), or ≥ 140 mmol/L (normal range). The association between admission serum sodium levels and long-term clinical events, a composite of all-cause deaths and re-hospitalizations for ADHF, was assessed by multivariable Cox proportional analysis.Of the 584 eligible patients, 208 (35.6%) were in the low-normal range and 99 (16.9%) had hyponatremia on admission. On multivariable analysis, compared with those with a sodium level ≥ 140 mmol/L, patients with hyponatremia were at increased risk for clinical events (hazard ratio [HR], 1.53; P = 0.041), whereas the HR of those in the low-normal range was attenuated and insignificant (HR, 1.08; P = 0.625). However, the HR of each category increased significantly as sodium level decreased (P value for HR trend, 0.024). In addition, when serum sodium level was treated as a continuous variable, the lower the serum sodium level, the greater the risk of clinical events (P = 0.012). The cut-off value of serum sodium level to predict mortality was < 138 mmol/L.In conclusion, a low serum sodium level on admission for ADHF, even if low-normal, can increase the risk of long-term mortality and/or re-hospitalization for ADHF.
尽管据报道急性失代偿性心力衰竭（ADHF）住院期间的低钠血症与不良预后相关，但关于入院时血清钠水平处于低正常范围内对ADHF患者临床事件影响的现有数据有限。我们研究了2007年至2011年入住我院的符合条件的患者。根据入院时血清钠水平将所有患者分为3组：<135 mmol/L（低钠血症）、≥135且<140 mmol/L（低正常范围）或≥140 mmol/L（正常范围）。通过多变量Cox比例分析评估入院时血清钠水平与长期临床事件（全因死亡和ADHF再次住院的综合情况）之间的关联。
在584例符合条件的患者中，208例（35.6%）血清钠水平处于低正常范围，99例（16.9%）入院时患有低钠血症。多变量分析显示，与血清钠水平≥140 mmol/L的患者相比，低钠血症患者发生临床事件的风险增加（风险比[HR]，1.53；P = 0.041），而血清钠水平处于低正常范围的患者的HR降低且无统计学意义（HR，1.08；P = 0.625）。然而，随着血清钠水平降低，各分类的HR显著增加（HR趋势的P值，0.024）。此外，当将血清钠水平视为连续变量时，血清钠水平越低，发生临床事件的风险越高（P = 0.012）。预测死亡率的血清钠水平临界值为<138 mmol/L。
总之，ADHF入院时血清钠水平低，即使处于低正常范围，也会增加ADHF长期死亡和/或再次住院的风险。
