Effect of different serum sodium levels on heart function and prognosis in very elderly patients with heart failure / 中华老年医学杂志

ABSTRACT

Objective To investigate the effect of different serum sodium levels on heart function and prognosis in very elderly patients with heart failure. Methods Totally 152 elderly patients(aged ≥ 85 years)with hyponatremia were enrolled.Based on the serum sodium level ,they were divided into mild(125 mmol/L ≤ Na+ < 135 mmol/L) ,moderate(125 mmol/L ≤ Na+ < 135 mmol/L) ,and severe hyponatremia(Na+ < 115 mmol/L)groups ,and 76 patients with normal blood sodium level(Na+ ≥ 135 mmol/L)were selected as control group. The general data ,levels of serum creatinine and N-terminal pro-brain natriuretic peptide (NTproBNP)and prognosis were compared among the above groups. Results Compared with the control group ,patients with severe hyponatremia were much older ,with more diuretics administration ,higher level of serum creatinine , lowerlevelofeGFRandleftventricularejectionfractions[(38.1±3.9)％ vs.(45.2±9.7)％ ].There were higher incidences of coronary atherosclerotic heart disease [72.4％ (n=21)vs. 56.6％ (n=43)] ,diabetes[41.4％ (n=12)vs. 23.7％ (n=18)] ,chronic renal insufficiency [22.6％ (n=8)vs. 11.8％ (n=9)] ,stroke[20.6％ (n=6)vs. 9.2％ (n=7)]in patients with severe hyponatremia compared with other groups. The severe hyponatremia group showed significantly higher levels of NTproBNP [(4823. 9 ± 588. 1 )ng/L v s. (1124. 4 ± 349. 1 )ng/L ,(1836. 2 ± 369. 3 )ng/L ,(2894. 1 ± 687. 3 )ng/L ]and higher rates of mortality [27.6％ (n=8) vs.5.3％ (n=4) ,7.6％ (n=6) ,13.6％ (n=6)]as compared to the control group ,mild and moderate hyponatremia groups. Furthermore ,length of stay in hospital were markedly longer in patients with severe hyponatremia than those with mild and moderate hyponatremia[(11.1 ± 7.1)d vs. (19.6 ± 5.7)d ,(16.1 ± 4.2)d] . Conclusions Hyponatremia is a common type of electrolyte disorder in very elderly patients with heart failure ,and severe hyponatremia may predictand increased risk of death.