Dysnatraemia in heart failure

Abstract

AimsTo investigate in detail the correlates of dysnatremia, and to estimate its differential prognostic relevance in patients with heart failure with reduced or preserved LVEF. BackgroundHyponatraemia has been shown to carry important prognostic information in patients with heart failure with reduced left ventricular ejection fraction (LVEF). However, exact serum sodium cut-off levels are not defined and the implications for heart failure with preserved ejection fraction (HF-pEF) are unclear. The prognostic value of hypernatraemia has not been investigated systematically. Therefore, the aim of this study was to investigate in detail the correlates of dysnatraemia, and to estimate its differential prognostic relevance in patients with heart failure with reduced or preserved LVEF. Methods and resultsOne thousand consecutive patients with heart failure of any cause and severity from the Würzburg Interdisciplinary Network for Heart Failure registry were included. Non-linear models for the association between serum sodium and mortality risk were calculated using restricted cubic splines and Cox proportional hazard regression. Median followup time for survivors was 5.1 years. ResultsIndependent correlates of dysnatraemia included guideline-recommended medication for chronic heart failure, indicators of renal function, and reverse associations with established cardiac risk factors. Overall mortality was 56%. Both hyponatraemia (n ¼ 72) and hypernatraemia (n ¼ 98) were associated with a significantly increased mortality risk: hazard ratio (HR) 2.10, 95% confidence interval (CI) 1.60-2.77; and HR 1.91, 95% CI 1.49-2.45, respectively. A U-shaped association of serum sodium with mortality risk was found. Prognosis was best for patients with high normal sodium levels, i.e. 140 -145 mmol/L. ConclusionsBoth hypo-and hypernatraemia indicate a markedly compromised prognosis in heart failure regardless of LVEF. Sodium levels within the reference range carry differential information on survival, with serum levels of 135-139 mmol/L indicating an increased mortality risk.--

Prognostic Significance of Baseline Serum Sodium in Heart Failure With Preserved Ejection Fraction

“…This is consistent with the study by Kovesdy et al28 showing a U‐shaped relationship between serum sodium level and mortality in patients with chronic kidney disease with and without HF. Hypernatremia has also been shown to be associated with increased mortality in the general population29 and patients with HFpEF 30. The mean age in this analysis is 70 years; elderly patients are at higher risk for developing hypernatremia because of an inability to replace water losses from physical and mental limitations to access water and decreased thirst perception.…”

Low-Normal Serum Sodium and Heart Failure-Related Events in Patients With Heart Failure With Preserved Left Ventricular Ejection Fraction

“…14, 18 Several recent clinical studies demonstrated that hyponatremia is an independent predictor of mortality in HFpEF patients and that sNa at admission for acute HF predicted the likelihood of cardiovascular death, with a relative risk for cardiovascular death of 1.08 for each 1-mmol/L decrease. 14, [19][20][21][22][23] In HFpEF patients after treatment according to the guideline, we investigated the prognostic significance of sNa as a continuous variable and low-normal sNa (135 mmol/L<sNa <140 mmol/L) for HF-related clinical events.…”

“…13,37 In the present study, we focused on lower sNa (sNa <140 mmol/L) based on the results of previous studies. 13, 20 Kaplan-Meier analysis showed that the lower sNa group (sNa <140 mmol/L) had a significantly higher probability of HF-related events.…”

Prevalence of Hyponatremia and Association with Mortality: Results from NHANES

“…27-29 Patients with hypernatremia (n=88), defined as sodium above the reference ranges, were excluded, given the differing etiologies of these derangements in serum sodium and to avoid confounding by the likely U shaped relationship between serum sodium and adverse outcomes. 4, 14, 30 As serum sodium was measured using indirect ion selective electrodes and direct measurements of serum osmolality were not available, we used estimates of plasma water content to identify cases of pseudohyponatremia and excluded these subjects from our analysis. 30,33 Sodium levels were corrected for the dilutional effect associated with hyperglycemia using the following previously validated methods: sodium corr = sodium + 1.6*((glucose-100)/100) for glucose between 200 and 400 mg/dL, and sodium corr = sodium + 3.2 + 2.4*((glucose -400)/100) for glucose ≥ 400 mg/dL.…”

“…Specifically, we identified participants with evidence of hypertension, diabetes, congestive heart failure 30 , liver disease 19 , kidney disease 5 , stroke 35 , Chronic Obstructive Pulmonary Disease 36 , cancer 23 , HIV 37 , depression and other psychiatric disorders. We also identified subjects who were using medications with known or suspected associations with hyponatremia including diuretics, angiotensin-converting-enzyme (ACE) inhibitors 38, 39 , angiotensin receptor blockers (ARBs), nonsteroidal anti-inflammatory agents (NSAIDs), selective serotonin reuptake inhibitors (SSRIs), and tricyclic antidepressants (TCAs) 40 , carbamazepine, and lamotrigine.…”