Mild hyponatremia, hypernatremia and incident cardiovascular disease and mortality in older men: A population-based cohort study

Association of baseline serum sodium with long-term outcomes in newly diagnosed coronary heart disease patients without heart failure: a prospective cohort study

Sodium is crucial for maintaining cardiovascular health, especially in relation to heart failure. The impact of baseline serum sodium concentrations on the outcomes of newly diagnosed coronary heart disease (CHD) without heart failure remains unclear. This prospective cohort study included 681 patients who were newly diagnosed with CHD. Cox proportional hazards models and restricted cubic spline (RCS) analysis were used to assess the relationship between serum sodium concentrations and major adverse cardiovascular events. The improvement in traditional prediction models by the addition of serum sodium concentrations was assessed using changes in the C-statistic, net reclassification improvement (NRI), and integrated discrimination improvement (IDI). During a median follow-up of 51.04 months (IQR: 40.88-53.80 months), 131 events were recorded. Multivariate Cox proportional hazards models showed that the L2 group (136-138.9 mmol/L) had the highest MACE risk. Compared to L2, the hazard ratios (HRs) and 95% confidence intervals (CIs) for the L1 (130-135.9 mmol/L), L3 (139-140.9 mmol/L), L4 (141-142.9 mmol/L), and L5 (143-147.0 mmol/L) groups were 0.31 (0.14-0.70, P = 0.005), 0.48 (030-0.78, P = 0.003), 0.56 (0.34-0.92, P = 0.022), and 0.37 (0.22-0.64, P < 0.001), respectively. Including serum sodium concentrations in the prediction model significantly improved the C-statistic from 0.647 to 0.679 (P = 0.022), with an NRI of 0.338 (P < 0.001) and an IDI of 0.026 (P < 0.001). RCS analysis showed a nonlinear relationship: within the 130-138 mmol/L sodium range, MACE risk gradually increased with higher sodium levels (HR 1.39, 95% CI 1.09-1.76, P = 0.008); whereas within the 138-147 mmol/L range, the risk gradually decreased (HR 0.88, 95% CI 0.80-0.98, P = 0.014). Baseline serum sodium concentrations are significantly associated with long-term cardiovascular risk in newly diagnosed CHD patients, showing an inverted U-shaped relationship, whereas low serum sodium may be specifically linked to higher risks of death and nonfatal myocardial infarction. Further research is needed to explore the impact of long-term changes in serum sodium concentrations on disease prognosis.

The Relationship between Serum Sodium Concentration and Albuminuria: A Retrospective Cohort Study

BACKGROUND

Lowering dietary salt intake reduces albuminuria, an early marker of renal damage and a sensitive predictor of adverse cardiovascular outcomes. The mechanisms underlying this effect are uncertain but small changes in serum sodium concentration may be important: this retrospective cohort study investigated the hypothesis that higher serum sodium concentration is a risk factor for albuminuria (defined as a urine albumin:creatinine ratio [UACR], ≥3 mg/mmol).

METHODS

Primary care data from the Royal College of General Practitioners Research and Surveillance Centre were used to identify 47,294 individuals with a UACR result available between April 2010 and March 2015, and no known albuminuria prior to this. Exclusion criteria were missing or abnormal serum sodium concentration at baseline (<135 or >146 mmol/L); age <18 years; diabetes mellitus; decompensated liver disease; heart failure; and stage 5 chronic kidney disease.

RESULTS

After adjustment for known risk factors, there was a significant "U-shaped" relationship between serum sodium concentration and albuminuria. The lowest risk was associated with a serum sodium of 138-140 mmol/L. In comparison, the risk of albuminuria was 18% higher with a serum sodium of 135-137 mmol/L and 19% higher with a serum sodium of 144-146 mmol/L. There was no association between serum sodium concentration and blood pressure.

CONCLUSION

The finding of a positive association between higher serum sodium concentration and albuminuria is in support of the hypothesis, but the inverse relationship between serum sodium concentration and albuminuria at lower concentrations warrants further explanation.

Hyponatremia, hypernatremia and impairment of functional, psychological and sexual domains

OBJECTIVE

To determine the influence of serum sodium on physical, psychologic and sexual function.

METHODS

This is a cross-sectional survey on 3340 community-dwelling men aged 40-79 years from a prospective cohort study in eight European countries, the European Male Ageing Study (EMAS). Participants filled-out the Short Form-36 (SF-36), the Physical Activity Scale for the Elderly (PASE), and the EMAS sexual function questionnaire. For all the analyses, serum sodium corrected for glycaemia ([Na+]G) was used.

RESULTS

The relationship between [Na+]G and SF-36 physical function score (F = 3.99; p = 0.01), SF-36 mental health score (F = 7.69; p < 0.001), and PASE score (F = 14.95; p < 0.001) were best described by a quadratic equation, with worse scores for [Na+]G in either the lowest or the highest ends of the range. After dividing the sample into [Na+]G < 136 mmol/L (n = 81), 136-147 mmol/L (n = 3223) and > 147 mmol/L (n = 36), linear regression analyses with linear spline functions adjusted for confounders did not confirm these relationships. Similarly, erectile dysfunction and [Na+]G, were in a quadratic relationship (F = 9.00; p < 0.001). After adjusting for confounders, the linear regression with spline functions denoted a significantly worsened erectile function for increases in serum [Na+]G > 147 mmol/L (B = 0.15 [0.04;0.26], p < 0.01) but no relationship with [Na+]G < 136 mmol/L. Likewise, the relationship of [Na+]G with concerns about sexual dysfunction was confirmed only for men with serum [Na+]G > 147 mmol/L.

CONCLUSIONS

This is the first study supporting an association between [Na+]G and sexual function. A worsening of erection and concerns about sexual function were observed for the highest values of [Na+]G, independently of other relevant factors.

[Construction and validation of an in-hospital mortality risk prediction model for patients receiving VA-ECMO: a retrospective multi-center case-control study]

OBJECTIVE

To investigate the risk factors of in-hospital mortality and establish a risk prediction model for patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

We retrospectively collected the data of 302 patients receiving VA-ECMO in ICU of 3 hospitals in Guangdong Province between January, 2015 and January, 2022 using a convenience sampling method. The patients were divided into a derivation cohort (201 cases) and a validation cohort (101 cases). Univariate and multivariate logistic regression analyses were used to analyze the risk factors for in-hospital death of these patients, based on which a risk prediction model was established in the form of a nomogram. The receiver operator characteristic (ROC) curve, calibration curve and clinical decision curve were used to evaluate the discrimination ability, calibration and clinical validity of this model.

RESULTS

The in-hospital mortality risk prediction model was established based the risk factors including hypertension (OR=3.694, 95% CI: 1.582-8.621), continuous renal replacement therapy (OR=9.661, 95%CI: 4.103-22.745), elevated Na2 + level (OR=1.048, 95% CI: 1.003-1.095) and increased hemoglobin level (OR=0.987, 95% CI: 0.977-0.998). In the derivation cohort, the area under the ROC curve (AUC) of this model was 0.829 (95% CI: 0.770-0.889), greater than those of the 4 single factors (all AUC < 0.800), APACHE II Score (AUC=0.777, 95% CI: 0.714-0.840) and the SOFA Score (AUC=0.721, 95% CI: 0.647-0.796). The results of internal validation showed that the AUC of the model was 0.774 (95% CI: 0.679-0.869), and the goodness of fit test showed a good fitting of this model (χ2=4.629, P>0.05).

CONCLUSION

The risk prediction model for in-hospital mortality of patients on VA-ECMO has good differentiation, calibration and clinical effectiveness and outperforms the commonly used disease severity scoring system, and thus can be used for assessing disease severity and prognostic risk level in critically ill patients.

A retrospective study: exploring preoperative hyponatremia in elderly patients with hip fractures

BACKGROUND

This research aims to examine the frequency, age-related distribution, and intensity of preoperative hyponatremia among elderly individuals with hip fractures. This study aims to provide valuable insights into the diagnosis of preoperative hyponatremia in this patient population.

METHODS

This research involved the analysis of clinical data obtained from 419 elderly individuals with hip fractures (referred to as the fracture group) and 166 elderly individuals undergoing routine health examinations (designated as the control group). A comprehensive comparison was conducted, examining baseline characteristics such as age, gender, and comorbidities between these two groups. We further investigated variations in the incidence rate of hyponatremia, age distribution, and the severity of hyponatremia. Additionally, a subgroup analysis compared patients with femoral neck fractures to those with intertrochanteric femur fractures, specifically examining the incidence rate and severity of hyponatremia in these distinct fracture types.

RESULTS

The incidence of cerebrovascular disease was found to be higher in the fracture group as compared to the control group in our research. Nevertheless, no significant differences in general health and other comorbidities were observed between the two groups. Notably, the fracture group exhibited a greater preoperative prevalence of hyponatremia, with its severity increasing with age. Furthermore, among elderly patients with intertrochanteric femur fractures, the incidence of preoperative hyponatremia was not only higher but also more severe when compared to those with femoral neck fractures.

CONCLUSION

Elderly individuals experiencing hip fractures exhibit a notable prevalence of preoperative hyponatremia, predominantly mild to moderate, with an escalating occurrence linked to advancing age. This phenomenon is especially conspicuous among patients with intertrochanteric fractures, warranting dedicated clinical scrutiny. The administration of sodium supplementation is advisable for the geriatric demographic as deemed necessary. Addressing hyponatremia becomes crucial, as it may play a role in the etiology of hip fractures in the elderly, and rectifying this electrolyte imbalance could potentially serve as a preventive measure against such fractures.

Influence of Fluid Ingestion on Heart Rate, Cardiac Autonomic Modulation and Blood Pressure in Response to Physical Exercise: A Systematic Review with Meta-Analysis and Meta-Regression

A systematic review was undertaken to investigate the involvement of hydration in heart rate (HR), HR variability (HRV) and diastolic (DBP) and systolic (SBP) blood pressure in response to exercise. Data synthesis: The EMBASE, MEDLINE, Cochrane Library, CINAHL, LILACS and Web of Science databases were searched. In total, 977 studies were recognized, but only 36 were included after final screening (33 studies in meta-analysis). This study includes randomized controlled trials (RCTs) and non-RCTs with subjects > 18 years old. The hydration group consumed water or isotonic drinks, while the control group did not ingest liquids. For the hydration protocol (before, during and after exercise), the HR values during the exercise were lower compared to the controls (-6.20 bpm, 95%CI: -8.69; -3.71). In the subgroup analysis, "water ingested before and during exercise" showed lower increases in HR during exercise (-6.20, 95%CI: 11.70 to -0.71), as did "water was ingested only during exercise" (-6.12, 95%CI: -9.35 to -2.89). Water intake during exercise only revealed a trend of avoiding greater increases in HR during exercise (-4,60, 95%CI: -9.41 to 0.22), although these values were not significantly different (p = 0.06) from those of the control. "Isotonic intake during exercise" showed lower HRs than the control (-7.23 bpm, 95% CI: -11.68 to -2.79). The HRV values following the exercise were higher in the hydration protocol (SMD = 0.48, 95%CI: 0.30 to 0.67). The values of the SBP were higher than those of the controls (2.25 mmHg, 95%CI: 0.08 to 4.42). Conclusions: Hydration-attenuated exercise-induced increases in HR during exercise, improved autonomic recovery via the acceleration of cardiac vagal modulation in response to exercise and caused a modest increase in SBP values, but did not exert effects on DBP following exercise.

Impact of serum sodium concentrations, and effect modifiers on mortality in the Irish Health System

BACKGROUND

Abnormalities of serum sodium are associated with increased mortality risk in hospitalised patients, but it is unclear whether, and to what extent other factors influence this relationship. We investigated the impact of dysnatraemia on total and cause-specific mortality in the Irish health system while exploring the concurrent impact of age, kidney function and designated clinical work-based settings.

METHODS

A retrospective cohort study of 32,666 participants was conducted using data from the National Kidney Disease Surveillance System. Hyponatraemia was defined as < 135 mmol/L and hypernatraemia as > 145 mmol/L with normal range 135-145 mmol/L. Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HR's) and 95% Confidence Intervals (CIs) while penalised spline models further examined patterns of risk.

RESULTS

There were 5,114 deaths (15.7%) over a median follow up of 5.5 years. Dysnatraemia was present in 8.5% of patients overall. In multivariable analysis, both baseline and time-dependent serum sodium concentrations exhibited a U-shaped association with mortality. Hyponatremia was significantly associated with increased risk for cardiovascular [HR 1.38 (1.18-1.61)], malignant [HR: 2.49 (2.23-2.78)] and non-cardiovascular/non-malignant causes of death [1.36 (1.17-1.58)], while hypernatremia was significantly associated with cardiovascular [HR: 2.16 (1.58-2.96)] and non-cardiovascular/ non-malignant deaths respectively [HR: 3.60 (2.87-4.52)]. The sodium-mortality relationship was significantly influenced by age, level of kidney function and the clinical setting at baseline (P < 0.001). For hyponatraemia, relative mortality risks were significantly higher for younger patients (interaction term P < 0.001), for patients with better kidney function, and for patients attending general practice [HR 2.70 (2.15-3.36)] than other clinical settings. For hypernatraemia, age and kidney function remained significant effect modifiers, with patients attending outpatient departments experiencing the greatest risk [HR 9.84 (4.88-18.62)] than patients who attended other clinical locations. Optimal serum sodium thresholds for mortality varied by level of kidney function with a flattening of mortality curve observed for patients with poorer kidney function.

CONCLUSION

Serum sodium concentrations outside the standard normal range adversly impact mortality and are associated with specific causes of death. The thresholds at which these risks appear to vary by age, level of kidney function, and are modified in specific clinical settings within the health system.

Massive Chronic Hypernatremia Associated With Failure to Thrive in a Pediatric Patient

Hypernatremia is a severe, potentially life-threatening condition that can manifest with altered mental status, coma, seizure, and even death. Values above 190 mmol/L are seldom reported in young pediatric patients and often have poor outcomes. We present a case of severe chronic hypernatremia secondary to failure to thrive (FTT) in a toddler, which led to significant pathology including bilateral metabolic strokes. A 21-month-old female was found unresponsive and brought to the hospital. The patient's childhood was complicated by prematurity, poor weight gain, and persistent postprandial emesis. On examination, the patient was tachycardic and obtunded. Her weight was below the first percentile. Initial laboratory results showed a sodium level of 197 mmol/L with marked dehydration. Normal saline boluses were given followed by maintenance fluids with the goal of sodium decrementation by 0.5 mmol/hour; nephrology assisted with fluid and electrolyte correction calculations. Imaging revealed metabolic strokes involving the brainstem and thalami. During hospitalization, hypokalemia and hypophosphatemia complicated the treatment course. Over the next 21 days, electrolytes normalized. She tolerated nasogastric feeding, gradually improved as she gained weight, and was discharged. Chronic hypernatremia must be fixed judiciously as rapid correction can cause significant harm. This unusual case reminds providers that florid electrolyte dyscrasias may be secondary to FTT and can lead to significant neurological sequelae. Careful fluid selection and calculations should be performed in these cases. Chronic hypernatremia should be considered in children with FTT with altered mental status, and the gradual correction of electrolytes should be performed to minimize patient harm.

Hyponatremia and mortality in patients undergoing maintenance hemodialysis: Systematic review and meta-analysis

INTRODUCTION

This systematic review and meta-analysis examined the relationship between hyponatremia and worse outcomes in patients undergoing maintenance hemodialysis.

METHODS

The MEDLINE, EMBASE, CENTRAL, and Web of Science databases were used to search for relevant articles. The target population was patients on maintenance hemodialysis (those undergoing hemodialysis for ≥60 days). The defined outcomes were death, cardiovascular disease, cognitive decline, and falls. Meta-analysis was performed with a random-effects model of pairwise comparisons of normonatremia and hyponatremia defined for each study, 1-mmol/L increment of sodium analysis, and dose-response analysis using the sodium concentration defined for each study. This study was registered with PROSPERO (registration number CRD42018087667).

RESULTS

Thirteen articles were included. The pairwise analysis revealed that the hazard ratio for all-cause mortality was 1.45 (95% confidence interval, 1.31-1.61). The analysis of 1-mmol/L increment of sodium included six studies with a hazard ratio for all-cause mortality of 0.94 (95% confidence interval, 0.91-0.97) for each 1-mmol/L increase in the serum sodium concentration. In the dose-response analysis, assuming a linear relationship, a sodium increment of 1 mmol/L revealed a hazard ratio for all-cause mortality of 0.97 (95% confidence interval, 0.96-0.98). Other outcomes could not be integrated.

CONCLUSIONS

Hyponatremia is associated with all-cause mortality in patients undergoing maintenance hemodialysis. Healthcare providers should pay special attention to even the slightest indication of hyponatremia.

Increased ICU mortality in septic shock patients with hypo- or hyper- serum osmolarity: A retrospective study

Background

While many factors that are associated with increased mortality in septic shock patients have been identified, the effects of serum osmolarity on the outcomes of ICU patients with septic shock have not yet been studied.

Methods

The present study was designed to examine the association of serum osmolarity with ICU 28-day mortality in ICU patients with septic shock. Adult patients diagnosed with septic shock from the MIMIC-IV database were selected in this study. The serum osmolarity was calculated synchronously according to the serum concentrations of Na⁺, K⁺, glucose, and urea nitrogen.

Results

In the present study, a significant difference was observed between the 28-day mortality of septic shock patients with hypo-osmolarity, hyper-osmolarity, and normal osmolarity (30.8%, 34.9%, and 23.0%, respectively, p < 0.001), which were detected at ICU admission. After propensity score matching (PSM) for basic characteristics, the relatively higher mortality was still observed in the hypo-osmolarity and hyper-osmolarity groups, compared to normal osmolarity group (30.6%, 30.0% vs. 21.7%, p = 0.009). Furthermore, we found that transforming the hyper-osmolarity into normal osmolarity by fluid therapy on day 2 and 3 decreased this mortality.

Conclusion

The serum osmolarity disorder is markedly associated with increased 28-day mortality in septic shock patients.

Middle-age high normal serum sodium as a risk factor for accelerated biological aging, chronic diseases, and premature mortality

BACKGROUND

It is known that some people age faster than others, some people live into old age disease-free, while others develop age-related chronic diseases. With a rapidly aging population and an emerging chronic diseases epidemic, finding mechanisms and implementing preventive measures that could slow down the aging process has become a new challenge for biomedical research and public health. In mice, lifelong water restriction shortens the lifespan and promotes degenerative changes. Here, we test the hypothesis that optimal hydration may slow down the aging process in humans.

METHODS

We performed a cohort analysis of data from the Atherosclerosis Risk in Communities study with middle-age enrollment (45-66 years, n = 15,752) and 25 years follow-up. We used serum sodium, as a proxy for hydration habits. To estimate the relative speed of aging, we calculated the biological age (BA) from age-dependent biomarkers and assessed risks of chronic diseases and premature mortality.

FINDINGS

The analysis showed that middle age serum sodium >142 mmol/l is associated with a 39% increased risk to develop chronic diseases (hazard ratio [HR] = 1.39, 95% confidence interval [CI]:1.18-1.63) and >144 mmol/l with 21% elevated risk of premature mortality (HR = 1.21, 95% CI:1.02-1.45). People with serum sodium >142 mmol/l had up to 50% higher odds to be older than their chronological age (OR = 1.50, 95% CI:1.14-1.96). A higher BA was associated with an increased risk of chronic diseases (HR = 1.70, 95% CI:1.50-1.93) and premature mortality (HR = 1.59, 95% CI 1.39-1.83).

INTERPRETATION

People whose middle-age serum sodium exceeds 142 mmol/l have increased risk to be biologically older, develop chronic diseases and die at younger age. Intervention studies are needed to confirm the link between hydration and aging.

FUNDING

This work was funded by Intramural Research program of the National Heart, Lung, and Blood Institute (NHLBI). The ARIC study has been funded in whole or in part with federal funds from the NHLBI; the National Institutes of Health (NIH); and the Department of Health and Human Services.

Hypernatremia During Intravenous Treatment With Fosfomycin: A Retrospective Medical Record Review Study and an Analysis of Spontaneous Reports in the EudraVigilance Database

Background: Hypernatremia is a serious event that can occur during intravenous (IV) treatment with fosfomycin, and it can also be caused by a wrong drug preparation. Considering the clinical significance of hypernatremia, we decided to carry out two studies by using two different data sources with the aim to evaluate cases of IV fosfomycin-induced hypernatremia.

Methods: A retrospective medical record review was performed from June 2017 to June 2019 using data from two hospitals in Southern Italy. The information collected was related to the patients, the antibiotic treatment regimen, type of adverse drug reaction (ADR), hypernatremia severity classification, and drug withdrawal due to ADRs. Moreover, a pharmacovigilance study was performed from the date of the European marketing authorization of fosfomycin to October 11, 2021, using data reported on the European website of suspected ADRs. Information related to the patient characteristics, treatment, hypernatremia, and type of reporter was retrieved.

Results: From the retrospective medical record review, a total of 62 patients (48 men and 14 women) in treatment with fosfomycin were identified, of which 17 experienced ADRs. Specifically, 11 patients experienced hypernatremia. During the period from June 2017 to June 2018, a total of 63.7% of hypernatremia events were related to the wrong reconstitution of the drug. According to these results, a surveillance and training campaign about the correct drug reconstitution was managed. However, from June 2018 to June 2019, we still had four new hypernatremia cases. Drug withdrawal occurred in only one patient with hypernatremia. From the pharmacovigilance study, a total of 25 cases of IV fosfomycin-induced hypernatremia were retrieved. No substantial difference was found for patients’ distribution by sex. Most cases were classified as serious (68%) and reported “Recovered/resolved” as the outcome (44%). In the majority of cases, fosfomycin was the only suspected drug reported (72%).

Conclusion: Our results show that training campaigns on the correct drug preparation need to be strengthened to allow a reduction of hypernatremia cases. Moreover, when close monitoring and management is performed by the infectious disease (ID) specialist and hospital pharmacist, there also is a reduction in antibiotic withdrawal due to hypernatremia.

A Novel Risk-Prediction Scoring System for Sepsis among Patients with Acute Pancreatitis: A Retrospective Analysis of a Large Clinical Database

Background

The prognosis is poor when acute pancreatitis (AP) progresses to sepsis; therefore, it is necessary to accurately predict the probability of sepsis and develop a personalized treatment plan to reduce the disease burden of AP patients.

Methods

A total of 1295 patients with AP and 43 variables were extracted from the Medical Information Mart for Intensive Care (MIMIC) IV database. The included patients were randomly assigned to the training set and to the validation set at a ratio of 7 : 3. The chi-square test or Fisher's exact test was used to test the distribution of categorical variables, and Student's t-test was used for continuous variables. Multivariate logistic regression was used to establish a prognostic model for predicting the occurrence of sepsis in AP patients. The indicators to verify the overall performance of the model included the area under the receiver operating characteristic curve (AUC), calibration curves, the net reclassification improvement (NRI), the integrated discrimination improvement (IDI), and a decision curve analysis (DCA).

Results

The multifactor analysis results showed that temperature, phosphate, calcium, lactate, the mean blood pressure (MBP), urinary output, Glasgow Coma Scale (GCS), Charlson Comorbidity Index (CCI), sodium, platelet count, and albumin were independent risk factors. All of the indicators proved that the prediction performance and clinical profitability of the newly established nomogram were better than those of other common indicators (including SIRS, BISAP, SOFA, and qSOFA).

Conclusions

The new risk-prediction system that was established in this research can accurately predict the probability of sepsis in patients with acute pancreatitis, and this helps clinicians formulate personalized treatment plans for patients. The new model can reduce the disease burden of patients and can contribute to the reasonable allocation of medical resources, which is significant for tertiary prevention.

The association between normal serum sodium levels and bone turnover in patients with type 2 diabetes

BACKGROUND

Sodium is a critically important component of bones, and hyponatremia has firmly been established as a risk factor associated with the incidence of fragility fractures. However, researches have also revealed that lower serum sodium are linked to reductions in muscle mass and a higher risk of cardiovascular disease even when these levels are within the normal range. Accordingly, this study was developed to examine the relationships between normal serum sodium concentrations and bone turnover in patients with type 2 diabetes (T2D).

METHODS

Patients with T2D were enrolled in the present study from January 2021 to April 2022. All patients underwent analyses of serum sodium levels, oral glucose tolerance testing (OGTT), bone turnover markers (BTMs), and dual-energy X-ray absorptiometry (DXA) scanning. BTMs included bone formation markers osteocalcin (OC) and N-terminal propeptide of type-I procollagen (PINP), and bone resorption marker C-terminal telopeptide (CTx). Patients were stratified into three subgroups based on the tertiles of their serum sodium concentrations.

RESULTS

In total, 372 patients with T2D and sodium levels in the normal range were enrolled in this study. Serum OC and PINP levels were increased from subgroup with the low sodium tertile to that with the high sodium tertile (p for trend < 0.05), whereas CTx level was comparable among the subgroups. A positive correlation was detected between serum sodium levels and both lnOC (r = 0.210, p < 0.001) and lnPINP (r = 0.196, p < 0.001), with these relationships remaining significant even following adjustment for age, sex, body mass index (BMI), and HbA1c. Only after adjusting for these four factors a positive correlation was detected between serum sodium levels and CTx levels (r = 0.108, p < 0.05). Linear regression analyses revealed that following adjustment for potential covariates, serum sodium level was and positively significantly associated with lnOC level (β = 0.134, t = 2.281, p < 0.05) and PINP level (β = 0.179, t = 3.023, p < 0.01).

CONCLUSION

These results highlight a significant association between low-normal serum sodium levels and low bone turnover.

Clues and new evidences in arterial hypertension: unmasking the role of the chloride anion

The present review will focus on the role of chloride anion in cardiovascular disease, with special emphasis in the development of hypertensive disease and vascular inflammation. It is known that acute and chronic overload of sodium chloride increase blood pressure and have pro-inflammatory and pro-fibrotic effects on different target organs, but it is unknown how chloride may influence these processes. Chloride anion is the predominant anion in the extracellular fluid and its intracellular concentration is dynamically regulated. As the queen of the electrolytes, it is of crucial importance to understand the physiological mechanisms that regulate the cellular handling of this anion including the different transporters and cellular chloride channels, which exert a variety of functions, such as regulation of cellular proliferation, differentiation, migration, apoptosis, intracellular pH and cellular redox state. In this article, we will also review the relationship between dietary, serum and intracellular chloride and how these different sources of chloride in the organism are affected in hypertension and their impact on cardiovascular disease. Additionally, we will discuss the approach of potential strategies that affect chloride handling and its potential effect on cardiovascular system, including pharmacological blockade of chloride channels and non-pharmacological interventions by replacing chloride by another anion.

Calculated plasma osmolality at hospital admission correlates well with eGFR and D-Dimer, a simple outcome predictor and guiding tool for management of severe COVID-19 patients

AIMS

To evaluate calculated total plasma osmolality as a marker of outcome prediction, fluid and metabolic balance, thrombotic risk in severe COVID-19 patients.

METHODS

Retrospective data of RT-PCR confirmed hospitalized severe COVID-19 patients (total: n = 175 patients, including diabetic subset: n = 102) were analyzed. Clinically applicable cut-offs were derived using receiver operating characteristic (ROC) curve analysis for calculated total osmolality, eGFR, and D-dimer, and their correlations were studied.

RESULTS

Among 175 severe COVID-19 patients, a significant association with mortality was seen with respect to calculated total osmolality (p < 0.001), eGFR (p < 0.001), and D-dimer (p < 0.001). In the total cohort, applicable cut-offs based on ROC curve in predicting outcome were, for total osmolality 299 mosm/kg (area under the curve (AUC)-0.773, odds ratio (OR)-1.09), eGFR 61.5 ml/min/m2 (AUC-0.789, OR-0.96), D-dimer 5.13 (AUC-0.814, OR-2.65) respectively. In diabetic subset, the cut-offs for total osmolality were 298 mosm/kg (AUC-0.794, OR-1.12), eGFR 44.9 ml/min/m2 (AUC-0.774, OR-0.96) and D-dimer 1.59 (AUC-0.769, OR-1.52) respectively.

CONCLUSIONS

Applicable cut-offs for calculated total plasma osmolality, eGFR, and D-dimer predicts clinical outcome in severe COVID-19 with and without diabetes. Correlation studies validated calculated total osmolality as a marker of the combined effect of fluid and metabolic imbalance, compromised renal function and hypercoagulability.

Sodium and Potassium Intake, the Sodium to Potassium Ratio, and Associated Characteristics in Older Adults, NHANES 2011-2016

BACKGROUND

Sodium, potassium, and the balance between these 2 nutrients are associated with hypertension and cardiovascular disease, and prevalence of these conditions increases with age. However, limited information is available on these intakes among older adults.

OBJECTIVE

Our aim was to explore the socioeconomic and health factors associated with usual sodium and potassium intakes and the sodium to potassium (Na:K) ratio of older adults.

DESIGN

This was a cross-sectional, secondary analysis of the 2011-2012, 2013-2014, and 2015-2016 National Health and Nutrition Examination Survey.

PARTICIPANTS/SETTING

This study included the data of 5,104 adults 50 years and older, with at least one reliable 24-hour dietary recall and an estimated glomerular filtration rate ≥60 mL/min/1.73 m².

MAIN OUTCOME MEASURES

Sodium and potassium intake, as absolute intake, density (per 1,000 kcal) and ratio of Na:K intake.

STATISTICAL ANALYSES

We used t tests and χ² tests to examine significant differences in intakes on a given day by characteristics. Linear and logistic regression models were used to assess associations of socioeconomic and health characteristics with usual sodium and potassium intakes, determined using the National Cancer Institute method.

RESULTS

Only 26.2% of participants consumed <2,300 mg sodium (16.2% of men and 35.2% of women) and 36.0% of men and 38.1% of women consumed at least 3,400 mg and 2,600 mg of potassium, respectively. Fewer than one-third of participants consumed a Na:K ratio of <1.0. Women, those with lower blood pressure, and those with a lower body mass index were more likely to have a ratio <1.0.

CONCLUSIONS

Participants consumed too much sodium and not enough potassium, based on current recommendations. A higher Na:K ratio was significantly associated with established risk factors for cardiovascular disease. The study findings suggest that more research on cardiovascular health should include both sodium and potassium, as well as balance between these nutrients.

The Association Between Plasma Osmolarity and In-hospital Mortality in Cardiac Intensive Care Unit Patients

Objectives: Plasma osmolarity is a common marker used for evaluating the balance of fluid and electrolyte in clinical practice, and it has been proven to be related to prognosis of many diseases. The purpose of this study was to identify the association between plasma osmolarity and in-hospital mortality in cardiac intensive care unit (CICU) patients.

Method: All of the patients were divided into seven groups stratified by plasma osmolarity, and the group with 290–300 mmol/L osmolarity was used as a reference group. Primary outcome was in-hospital mortality. The local weighted regression (Lowess) smoothing curve was drawn to determine the “U”-shaped relationship between plasma osmolarity and in-hospital mortality. Binary logistic regression analysis was performed to determine the effect of plasma osmolarity on the risk of in-hospital mortality.

Result: Overall, 7,060 CICU patients were enrolled. A “U”-shaped relationship between plasma osmolarity and in-hospital mortality was observed using the Lowess smoothing curve. The lowest in-hospital mortality (7.2%) was observed in the reference group. whereas hyposmolarity (<280 mmol/L vs. 290–300 mmol/L: 13.0 vs. 7.2%) and hyperosmolarity (≥330 mmol/L vs. 290–300 mmol/L: 31.6 vs. 7.2%) had higher in-hospital mortality. After adjusting for possible confounding variables with binary logistic regression analysis, both hyposmolarity (<280 mmol/L vs. 290–300 mmol/L: OR, 95% CI: 1.76, 1.08–2.85, P = 0.023) and hyperosmolarity (≥330 mmol/L vs. 290–300 mmol/L: OR, 95% CI: 1.65, 1.08–2.52, P = 0.021) were independently associated with an increased risk of in-hospital mortality. Moreover, lengths of CICU and hospital stays were prolonged in patients with hyposmolarity or hyperosmolarity.

Conclusion: A “U”-shaped relationship between plasma osmolarity and in-hospital mortality was observed. Both hyposmolarity and hyperosmolarity were independently associated with the increased risk of in-hospital mortality.

Level of natremia as an index of the condition of the organism of animals under stress

In the diagnosis of stressful conditions in humans and other animals, ionic indicators remain practically unused. In this work, we studied the changes in the concentrations of sodium ions in the blood plasma of freshwater fish under stress caused by stressors of different quality and quantity. Most of the experiments were carried out on adult bream (Abramis brama L) from the Rybinsk Reservoir. Separate experiments were duplicated on adult individuals of roach (Rutilus rutilus L.), pike (Esox lucius L.), and blue bream (Abramis ballerus L.). The concentration of cations in the blood plasma was determined using a Flapho-4 flame photometer. Under the action of mild and short-term stressors of different qualities, the sodium concentration in the internal environment altered toward an increase in concentration gradients on the cell membrane (eustress or physiological stress). Hypernatremia was approximately 10%. Under the action of strong and/or prolonged stressors of different strength, the sodium concentration in the internal environment changed toward a decrease in concentration gradients on the cell membrane (distress or pathological stress). Hyponatremia was 50% in the conditions of acute lethal stress, 20% in subacute lethal stress, 10% or more in chronic lethal stress. During strong acute reversible stress, hyponatremia could reach 30%. Analysis of the material on mammals allowed us to conclude that the adaptation mechanisms in fish and higher vertebrates are similar. In this work, for the first time, the state of the system of electrolyte balance of animals under stress was analyzed from the standpoint of the leading role of ionic concentration gradients on the cell membrane (mainly sodium) in the energetics (level of disequilibrium) of the organism. We propose a concept that in normal and extreme conditions fish use two different defense reactions (or adaptation strategies): active and passive, consisting, respectively, in increasing or decreasing the level of disequilibrium (energy) in the organism. The hyponatremia recorded by numerous authors, which accompanies diseases in humans, is evidently a nonspecific reaction of the organism and serves as an indicator of reduced energy of the organism. It is suggested that the sodium level in the internal environment of the organism be used for diagnosing the stress state of animals.

Association between serum sodium level within normal range and handgrip strength in relation to hypertension status: a cross-sectional study

Serum sodium concentration within the normal range could act as an indicator of age-related changes such as decrease in muscle strength and impairment of capillary function. Since endothelial injury stimulates endothelial repair by enhancing CD34-positive cell production, the level of serum sodium may be inversely associated with that of circulating CD34-positive cells, thus indicating the degree of age-related endothelial injury. We conducted a cross-sectional study of 246 elderly Japanese men aged 60–69 years. Subjects were stratified by hypertension status because hypertension should act as a strong confounding factor for the analyses performed in this study. Serum sodium concentration was positively associated with handgrip strength in non-hypertensive subjects [standardized parameter estimate (β) = 0.29; p = 0.003], but not for hypertensive subjects (β = 0.01; p = 0.878), while it was inversely associated with circulating CD34-positive cell levels in non-hypertensive subjects [simple correlation coefficient (r) = − 0.28; p = 0.002] but not for hypertensive subjects (r = − 0.07; p = 0.454). For non-hypertensive elderly subjects, serum sodium concentration within the normal range is positively associated with handgrip strength and inversely associated with CD34-positive cells, thus partly indicating the degree of age-related endothelium injury. These associations could prove to be an efficient tool for clarifying the background mechanism governing the decrease in age-related muscle strength.

Hyperosmolarity Deserves More Attention in Critically Ill COVID-19 Patients with Diabetes: A Cohort-Based Study

PURPOSE

Recently, a cluster of pneumonia caused by SARS-CoV-2 were identified in Wuhan and spread throughout the world. More information about risk factors for mortality of critically ill patients infected with SARS-CoV-2 remain to be evaluated.

METHODS

We included adult patients confirmed with SARS-CoV-2 infection who were critically ill and admitted to the intensive care unit (ICU) of Tongji Hospital in Wuhan from Feb 4, 2020 to Feb 20, 2020. Data were collected and compared between patients who died and improved. Logistic regression was used to explore the risk factors for death of SARS-CoV-2-infected critically ill patients.

RESULTS

A total of 160 critically ill patients with SARS-CoV-2 infection were included, of which 146 patients with appeared outcomes were included into the final analysis. The random blood glucose, serum sodium and effective plasma osmolarity were higher in deceased patients, especially in patients with diabetes. There were 7 patients with diabetes with hyperosmolar status and all of them were deceased. Multivariable regression revealed that older age (odds ratio 4.28, 95% CI 1.01-18.20; p = 0.049), higher C-reactive protein (odds ratio 1.01, 1.00-1.03; p = 0.024), higher interleukin-6 (odds ratio 1.01, 1.00-1.03; p = 0.0323), and d-dimer greater than 1 μg/mL (odds ratio 1.10, 1.01-1.20; p = 0.032) at admission were associated with increased odds of death.

CONCLUSION

In conclusion, hyperosmolarity needs more attention and may contribute to mortality in critically ill patients with COVID-19, especially in those with diabetes. Older age, inflammatory response, and thrombosis may be risk factors for death of critically ill patients with SARS-CoV-2 infection.

Water Researchers Do Not Have a Strategic Plan for Gathering Evidence to Inform Water Intake Recommendations to Prevent Chronic Disease

Confusion has persisted for decades in the United States (U.S.) over how much plain water to drink, despite national water intake recommendations which are based on high quality scientific evidence. This editorial summarizes the definition, alignment and coordination of evidence that informs the current U.S. adequate intake (AI) recommendations for water. It highlights gaps in the evidence that perpetuate confusion and opportunity to address the gaps through strategic planning.

Low serum sodium concentrations in patients with obesity normalizes with weight loss

BACKGROUND & AIMS

Obesity is associated with higher extracellular fluid (ECF) compared to intracellular fluid (ICF) volume and this dysregulation is associated with hypertension and abdominal obesity, associated with metabolic syndrome. As sodium is predominantly an extracellular cation, a higher ECF/ICF ratio will lower serum sodium concentration. The aim of the study was to see whether weight loss, due to dieting and bariatric surgery, had any impact on serum sodium concentrations in patients with severe obesity.

METHODS

Patients with a BMI ≥35 kg/m² admitted for bariatric surgery at Innlandet Hospital Trust, Norway during 2012-14 were included in the study (n = 119). Clinical data and blood samples were recorded at inclusion, after mean six months of dieting, as well as six and 12 months after bariatric surgery.

RESULTS

At inclusion, mean serum sodium was in the lower normal range, 138.3 (SD 2.4) mmol/L, but increased to 141.8 (SD 1.9) mmol/L after weight loss. The increase was significantly correlated to total weight loss (rho: 0.29, p = 0.007). Twelve months after surgery, serum sodium was significantly higher in patients with a normal BMI (<25 kg/m²) compared to patients with overweight.

CONCLUSION

Obesity and hypertension are associated with body fluid dysregulation affecting serum sodium concentrations. As mild hyponatremia, even within the normal sodium range, is associated with increased total mortality and major cardiovascular disease events, serum sodium might be a potential risk marker in patients with obesity.

Lower serum sodium levels predict poor clinical outcomes in patients with insomnia

Background

The association between lower serum sodium levels and the clinical outcomes of insomnia patients remains unclear. We explored whether lower serum sodium is associated with poor clinical outcomes in patients with insomnia.

Methods

We retrospectively enrolled patients with a diagnosis of insomnia from January 2011 to December 2012. We divided participants into three groups according to initial serum sodium level: tertile 1 (< 138 mmol/L), tertile 2 (138.0–140.9 mmol/L), and tertile 3 (≥ 141.0 mmol/L). To calculate the relative risk of death, hazard ratios (HRs) and 95% confidence intervals (CIs) were obtained using Cox proportional hazard models.

Results

A total of 412 patients with insomnia were included, of whom 13.6% (n = 56) had hyponatremia. Patients with lower serum sodium concentrations were older and had lower hemoglobin, calcium, phosphorus, and albumin levels. At the median follow-up of 49.4 months, 44 patients had died and 62 experienced acute kidney injury (AKI). Kaplan-Meier analysis showed significantly higher mortality in patients in the lowest tertile for serum sodium. The lowest tertile of the serum sodium level and the AKI were associated with all-cause mortality. However, the lowest tertile of the serum sodium level was not significantly associated with AKI.

Conclusions

The lowest tertile of the serum sodium level was associated with a higher mortality rate in insomnia patients. Our results suggest that the serum sodium level could serve as a prognostic factor in insomniacs; patients with lower sodium levels require particular care.

Underhydration Is Associated with Obesity, Chronic Diseases, and Death Within 3 to 6 Years in the U.S. Population Aged 51-70 Years

Nationally representative data from the National Health and Nutrition Examination Survey (NHANES) indicate that over 65% of adults aged 51–70 years in the U.S. do not meet hydration criteria. They have hyponatremia (serum sodium < 135 mmol/L) and/or underhydration (serum sodium >145 mmol/L, spot urine volume <50 mL, and/or spot urine osmolality ≥500 mmol/kg). To explore potential public health implications of not meeting hydration criteria, data from the NHANES 2009–2012 and National Center for Health Statistics Linked Mortality Files for fasting adults aged 51–70 years (sample n = 1200) were used to determine if hyponatremia and/or underhydration were cross-sectionally associated with chronic health conditions and/or longitudinally associated with chronic disease mortality. Underhydration accounted for 97% of the population group not meeting hydration criteria. In weighted multivariable adjusted Poisson models, underhydration was significantly associated with increased prevalence of obesity, high waist circumference, insulin resistance, diabetes, low HDL, hypertension, and metabolic syndrome. Over 3–6 years of follow-up, 33 chronic disease deaths occurred in the sample, representing an estimated 1,084,144 deaths in the U.S. Alongside chronic health conditions, underhydration was a risk factor for an estimated 863,305 deaths. Independent of the chronic health conditions evaluated, underhydration was a risk factor for 128,107 deaths. In weighted multivariable Cox models, underhydration was associated with 4.21 times greater chronic disease mortality (95% CI: 1.29–13.78, p = 0.019). Zero chronic disease deaths were observed for people who met the hydration criteria and did not already have a chronic condition in 2009–2012. Further work should consider effects of underhydration on population health.

Serum Sodium and Pulse Pressure in SPRINT

BACKGROUND

High dietary sodium intake may induce a small, yet physiologically relevant rise in serum sodium concentration, which associates with increased systolic blood pressure. Cellular data suggest that this association is mediated by increased endothelial cell stiffness. We hypothesized that higher serum sodium levels were associated with greater arterial stiffness in participants in the Systolic Blood Pressure Intervention Trial (SPRINT).

METHODS

Multivariable linear regression was used to examine the association between baseline serum sodium level and (i) pulse pressure (PP; n = 8,813; a surrogate measure of arterial stiffness) and (ii) carotid-femoral pulse wave velocity (CFPWV; n = 591 in an ancillary study to SPRINT).

RESULTS

Baseline mean ± SD age was 68 ± 9 years and serum sodium level was 140 ± 2 mmol/L. In the PP analysis, higher serum sodium was associated with increased baseline PP in the fully adjusted model (tertile 3 [≥141 mmol] vs. tertile 2 [139-140 mmol]; β = 0.87, 95% CI = 0.32 to 1.43). Results were similar in those with and without chronic kidney disease. In the ancillary study, higher baseline serum sodium was not associated with increased baseline CFPWV in the fully adjusted model (β = 0.35, 95% CI = -0.14 to 0.84).

CONCLUSIONS

Among adults at high risk for cardiovascular events but free from diabetes, higher serum sodium was independently associated with baseline arterial stiffness in SPRINT, as measured by PP, but not by CFPWV. These results suggest that high serum sodium may be a marker of risk for increased PP, a surrogate index of arterial stiffness.

Hyponatremia and mortality among very elderly residents in a geriatric health service facility

INTRODUCTION

Hyponatremia is common among elderly patients. This study aimed to examine the prognostic value of hyponatremia among elderly residents in a geriatric facility.

METHODS

We retrospectively examined the association between serum sodium levels and mortality among 118 residents (82% female, mean age 85.5 years) in a single geriatric health service facility. We defined hyponatremia as Na < 135 mEq/L. On the basis of single measurements of serum sodium at periodic examinations, the patients were divided into hyponatremia and non-hyponatremia groups. Multivariable Cox proportional hazards models were used to evaluate the effect of hyponatremia on mortality from May 2005 to April 2007.

RESULTS

Thirty-three patients (28%) had hyponatremia. Over a 1-year follow-up period, the cumulative survival rate was significantly lower in patients with hyponatremia than in those without hyponatremia. In a multivariate analysis, including traditional risk factors for death, hyponatremia was associated with an increased mortality risk (adjusted hazard ratio 2.73; 95% confidence interval 1.01-5.16; p = 0.047).

CONCLUSIONS

Hyponatremia is common and is a predictor of mortality in the near future among very elderly residents of a geriatric facility.

Risk of Cardiovascular Mortality Associated With Serum Sodium and Chloride in the General Population

BACKGROUND

The prognostic value of serum chloride among patients with heart failure was demonstrated by previous studies. However, the association of serum chloride and risk of cardiovascular mortality among the general population remains unclear.

METHODS

We included 16,483 participants in National Health and Nutrition Examination Survey III. Cox proportional hazards models were used to assess the association of serum sodium and chloride and cardiovascular mortality. Potential confounders were included in the models. Levels of serum sodium and chloride were also modeled with restrictive cubic splines for potential nonlinear associations. Subgroup analyses were based on baseline diseases and use of diuretics.

RESULTS

The mean age was 43.5 years, and 47.8% of the participants were men. During 277,059 person-years of follow-up, there were 1714 cardiovascular deaths. In the multivariate model, low-level serum sodium was associated with an increased risk of cardiovascular mortality (hazard ratio [HR], 1.10; 95% confidence interval [CI], 1.02-1.18 per standard deviation [SD]; P = 0.009), whereas a lower level of serum chloride was not (HR, 1.04; 95% CI, 0.97-1.12 per standard deviation; P = 0.278). Analyses with restrictive cubic splines yielded similar results.

CONCLUSIONS

Low serum sodium, rather than chloride, was independently associated with an increased risk of cardiovascular mortality.

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

BACKGROUND

The purpose of this study was to evaluate the relationship between serum sodium at the time of diagnosis and long term clinical outcomes in a large national cohort of patients with heart failure with preserved ejection fraction.

METHODS AND RESULTS

We studied 25 440 patients with heart failure with preserved ejection fraction treated at Veterans Affairs medical centers across the United States between 2002 and 2012. Serum sodium at the time of heart failure diagnosis was analyzed as a continuous variable and in categories as follows: low (115.00-134.99 mmol/L), low-normal (135.00-137.99 mmol/L), referent group (138.00-140.99 mmol/L), high normal (141.00-143.99 mmol/L), and high (144.00-160.00 mmol/L). Multivariable Cox regression and negative binomial regression were performed to estimate hazard ratios (95% confidence interval [CI]) and incidence density ratios (95% CI) for the associations of serum sodium with mortality and hospitalizations (heart failure and all-cause), respectively. The average age of patients was 70.8 years, 96.2% were male, and 14% were black. Compared with the referent group, low, low-normal, and high sodium values were associated with 36% (95% CI, 28%-44%), 6% (95% CI, 1%-12%), and 9% (95% CI, 1%-17%) higher risk of all-cause mortality, respectively. Low and low-normal serum sodium were associated with 48% (95% CI, 10%-100%) and 38% (95% CI, 8%-77%) higher risk of number of days of heart failure hospitalizations per year, and with 44% (95% CI, 32%-56%) and 18% (95% CI, 10%-27%) higher risk of number of days of all-cause hospitalizations per year, respectively.

CONCLUSIONS

Both elevated and reduced serum sodium, including values currently considered within normal range, are associated with adverse outcomes in patients with heart failure with preserved ejection fraction.

Sodium levels during hospitalization with acute myocardial infarction are markers of in-hospital mortality: Soroka acute myocardial infarction II (SAMI-II) project

OBJECTIVE

Abnormalities in sodium homeostasis are common in hospitalized patients. Hyponatremia upon admission is a poor prognostic marker in acute myocardial infarction (AMI) patients. However, little is known about the association between changes in sodium levels and in-hospital mortality. We delineated changes in sodium levels and studied the association of such changes with in-hospital mortality of AMI patients.

METHODS

Retrospective analysis of AMI patients hospitalized for > 6 days. Sodium levels throughout the 6-day post-admission were divided into five equally sized groups (quintiles = Q) and thereafter categorized as follows: Q1 (< 135 mEq/L), Q2-Q4 (135-140 mEq/L, reference group), and Q5 (≥141 mEq/L).

PRIMARY OUTCOME

in-hospital mortality.

RESULTS

A total of 8306 patients (10,416 admissions) were included (mean age 67.8 ± 14.0 years, 33.4% women, 45.5% STEMI). In-hospital mortality was 6.6%. Q1 and Q5 upon admission were both related to higher risk for in-hospital mortality, compared with the reference group (OR 1.47 and OR 1.33, respectively, p < 0.001 each). Q1 was more frequent in non-survivors throughout the entire study period, while the prevalence of Q5 levels was similar in survivors and non-survivors upon admission carrying increasing mortality risk thereafter: for Q1 consistent OR 1.50, while for Q5 it, increased from OR 1.32 upon admission to OR 1.90 on the sixth day, p < 0.001.

CONCLUSIONS

Low and high sodium levels are associated with increased risk for in-hospital mortality in patients with AMI. The risk is unchanged for hyponatremia, while it consistently increases for increased sodium levels.

Not Salt But Sugar As Aetiological In Osteoporosis: A Review

Salt has notoriously been blamed for causing an increase in the urinary excretion of calcium, and thus is a considered a risk factor for osteoporosis. However, the increase in the urinary excretion of calcium with higher sodium intakes can be offset by the increased intestinal absorption of dietary calcium. Thus, the overall calcium balance does not appear to be reduced with a higher sodium intake. However, the other ubiquitous white crystal, sugar, may lead to osteoporosis by increasing inflammation, hyperinsulinemia, increased renal acid load, reduced calcium intake, and increased urinary calcium excretion. Sugar, not salt, is the more likely white crystal to be a risk factor for osteoporosis when overconsumed.

Associations of dysnatremias with mortality in chronic kidney disease

Background

Hyponatremia and hypernatremia are associated with death in the general population and those with chronic kidney disease (CKD). We studied the associations between dysnatremias, all-cause mortality and causes of death in a large cohort of Stage 3 and 4 CKD patients.

Methods

We included 45 333 patients with Stage 3 and 4 CKDs followed in a large healthcare system. Associations between hyponatremia (<136 mmol/L) and hypernatremia (>145), and all-cause mortality and causes of death (cardiovascular, malignancy related and non-cardiovascular/non-malignancy related) were studied using Cox proportional hazards and competing risk models.

Results

Dysnatremias were found in 9.2% of the study population. In separate multivariable Cox proportional hazards models using baseline serum sodium levels and time-dependent repeated measures, both hyponatremia and hypernatremia were associated with all-cause mortality. In the competing risk analyses, hyponatremia was significantly associated with increased risk for various cause-specific mortality categories [cardiovascular (hazard ratio, HR 1.16, 95% confidence interval, CI: 1.04, 1.30), malignancy related (HR 1.48, 95% CI: 1.33, 1.65) and non-cardiovascular/non-malignancy deaths (HR 1.25, 95% CI: 1.13, 1.39)], while hypernatremia was significantly associated with higher non-cardiovascular/non-malignancy mortality only (HR 1.36, 95% CI: 1.08, 1.72).

Conclusions

In those with CKD, hyponatremia was associated with all-cause mortality, cardiovascular, malignancy and non-cardiovascular/non-malignancy-related deaths. Hypernatremia was associated with all-cause and non-cardiovascular/non-malignancy-related deaths. Further studies are needed to elucidate the mechanisms of differences in cause-specific death among CKD patients with hyponatremia and hypernatremia.

Serum Sodium and Cognition in Older Community-Dwelling Men

BACKGROUND AND OBJECTIVES

Mild hyponatremia is a common finding in older adults; however, the association of lower serum sodium with cognition in older adults is currently unknown. We determined whether lower normal serum sodium is associated with cognitive impairment and risk of cognitive decline in community-dwelling older men.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Five thousand four hundred thirty-five community-dwelling men aged ≥65 years who participated in Osteoporotic Fractures in Men, a cohort study with a median follow-up for cognitive function of 4.6 years, were included in this analysis. Multivariable logistic regression was used to examine the association between baseline fasting serum sodium levels and the odds of prevalent cognitive impairment (cross-sectional analysis; modified Mini-Mental Status [3MS] score <1.5 SD [<84] below or Trail Making Test Part B time >1.5 SD above the mean [>223 seconds]) and cognitive decline (prospective analysis [n=3611]; decrease in follow-up 3MS score or increase in Trails B time >1.5 SD of the mean score/time change [>9 or >67 seconds]).

RESULTS

Participants were aged 74±6 years with a fasting mean serum sodium level of 141±3 mmol/L. Fifteen percent (n=274), 12% (n=225), and 13% (n=242) had prevalent cognitive impairment in tertiles 1, 2, and 3, respectively. After adjustment, lower serum sodium was associated with prevalent cognitive impairment (tertile 1 [126-140 mmol/L] versus tertile 2 [141-142 mmol/L], odds ratio [OR], 1.30; 95% confidence interval [95% CI], 1.06 to 1.61). Fourteen percent (n=159), 10% (n=125), and 13% (n=159) had cognitive decline in tertiles 1, 2, and 3, respectively. Lower serum sodium was also associated with cognitive decline (tertile 1 versus tertile 2, OR, 1.37; 95% CI, 1.06 to 1.77). Tertile 3 (143-153 mmol/L) was additionally associated with cognitive decline. Results were similar in sensitivity analyses according to clinical cut-offs and by quartiles.

CONCLUSIONS

In community-dwelling older men, serum sodium between 126-140, and 126-140 or 143-153 mmol/L, are independently associated with prevalent cognitive impairment and cognitive decline, respectively.

Hospital-Associated Hypernatremia Spectrum and Clinical Outcomes in an Unselected Cohort

BACKGROUND

Although hypernatremia is associated with adverse outcomes, most studies examined selected populations.

METHODS

Discharge data of 19,072 unselected hospitalized adults were analyzed. The crude relationship between serum sodium [Na⁺] and mortality defined hypernatremia as serum [Na⁺] >142 mEq/L. Patients with community-acquired hypernatremia or hospital-acquired hypernatremia were compared with normonatremic patients (admission [Na⁺] 138-142 mEq/L) regarding in-hospital mortality, length of stay, and discharge disposition. Patients with community-acquired hypernatremia whose hypernatremia worsened during hospitalization were compared with those without aggravation.

RESULTS

Community-acquired hypernatremia occurred in 21% of hospitalized patients and was associated with an adjusted odds ratio (OR) of 1.67 (95% confidence interval [CI], 1.38-2.01) for in-hospital mortality and 1.44 (95% CI, 1.32-1.56) for discharge to a short-/long-term care facility and an adjusted 10% (95% CI, 7-13) increase in length of stay. Hospital-acquired hypernatremia developed in 25.9% of hospitalized patients and was associated with an adjusted OR of 3.17 (95% CI, 2.45-4.09) for in-hospital mortality and 1.45 (95% CI, 1.32-1.59) for discharge to a facility, and an adjusted 49% (95% CI, 44-53) increase in length of stay. Hospital-aggravated hypernatremia developed in 11.7% of patients with community-acquired hypernatremia and was associated with greater risk of in-hospital mortality (adjusted OR, 1.84; 95% CI, 1.32-2.56) and discharge to a facility (adjusted OR, 2.14; 95% CI, 1.71-2.69), and an adjusted 16% (95% CI, 7-27) increase in length of stay.

CONCLUSIONS

The hypernatremia spectrum in unselected hospitalized patients is independently associated with increased in-hospital mortality and heightened resource consumption.

Hyponatremia and increased risk of dementia: A population-based retrospective cohort study

Hyponatremia is the most common electrolyte disorder and also a predictor of mild cognition impairment. However, the association between hyponatremia and dementia in long follow up periods is rarely investigated. A retrospective cohort study was performed using the claims data of all insured residents who were covered by Taiwan’s universal health insurance from 2000 to 2011. A total of 4900 hyponatremia patients and 19545 matched comparisons were recruited for the analysis. The incidences of hyponatremia and dementia were diagnosed with clinical protocol and defined using the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM). Cox proportional hazard regression and Kaplan–Meier curves were used for the analyses. Independent of adjusting factors, hyponatremia patients had 2.36-fold higher chances of suffering dementia, including Alzheimer’s disease (AD) and non-AD dementia, than the comparisons. Severe hyponatremia patients had higher risks of suffering dementia than the non-severe hyponatremia patients (adjusted hazard ratio: 4.29 (95% CI: 3.47–5.31) versus 2.08 (95% CI: 1.83–2.37)). A dose response relationship was observed between hyponatremia and dementia. Those hyponatremia patients with baseline or incident stroke had significantly higher chances of suffering dementia compared with those patients without hyponatremia and stroke. Stroke is a significant modifier of the relationship between hyponatremia and dementia. Cerebrovascular disease after incident hyponatremia must be prevented to reduce the incidence of dementia.

Association between serum osmolarity and mortality in patients who are critically ill: a retrospective cohort study

OBJECTIVES

This research aims to explore the association between serum osmolarity and mortality in patients who are critically ill with specific categories of disease.

DESIGN

A retrospective cohort study.

SETTING AND PARTICIPANTS

Data were extracted from an online database named 'Multiparameter Intelligent Monitoring in Intensive Care II'. 16 598 patients were included.

METHODS

Patients were divided into six disease subgroups based on the diagnosis at admission: cardiac, cerebral, vascular, gastrointestinal, respiratory and non-respiratory. The association between maximum osmolarity (osmolarity_max) and hospital mortality in each subgroup was evaluated using osmolarity_max as a design variable (six levels).

RESULTS

Analysis of the 16 598 patients revealed a 'U'-shaped relationship between osmolarity and mortality with a threshold of 300 mmoL/L. For patients with non-respiratory disease, both hypo-osmolarity and hyperosmolarity_max were associated with increased mortality, with the OR increasing from osmolarity_max level 3 (OR: 1.98, 95% CI 1.69 to 2.33, p<0.001) to level 6 (OR: 4.45, 95% CI 3.58 to 5.53, p<0.001), using level 2 (290-309 mmoL/L) as the reference group. For patients with respiratory disease, however, neither hypo-osmolarity nor hyperosmolarity_max was significantly associated with mortality (levels 1 to 5) except for extreme hyperosmolarity_max (≥340 mmoL/L, OR: 2.03, 95% CI 1.20 to 3.42, p=0.007). ORs of mortality in the other four subgroups (cardiac, cerebral, vascular, gastrointestinal) were similar, with OR progressively increasing from level 3 to 6. In all six subgroups, vasopressin use was consistently associated with increased mortality.

CONCLUSIONS

Hyperosmolarity is associated with increased mortality in patients who are critically ill with cardiac, cerebral, vascular and gastrointestinal admission diagnoses, with thresholds at 300 mmoL/L. For patients with respiratory disease, however, no significant association was detected.

Pressure ulcers in palliative ward patients: hyponatremia and low blood pressure as indicators of risk

BACKGROUND

Prevention strategies for pressure ulcer formation remain critical in patients with an advanced illness. We analyzed factors associated with the development of pressure ulcers in patients hospitalized in a palliative care ward setting.

PATIENTS AND METHODS

This study was a retrospective analysis of 329 consecutive patients with a mean age (± standard deviation) of 70.4±11.8 years (range: 30-96 years, median 70.0 years; 55.3% women), who were admitted to the Palliative Care Department between July 2012 and May 2014.

RESULTS

Patients were hospitalized for mean of 24.8±31.4 days (1-310 days, median 14 days). A total of 256 patients (77.8%) died in the ward and 73 patients (22.2%) were discharged. Two hundred and six patients (62.6%) did not develop pressure ulcers during their stay in the ward, 84 patients (25.5%) were admitted with pressure ulcers, and 39 patients (11.9%) developed pressure ulcers in the ward. Four factors assessed at admission appear to predict the development of pressure ulcers in the multivariate logistic regression model: Waterlow score (odds ratio [OR] =1.140, 95% confidence interval [CI] =1.057-1.229, P=0.001), transfer from other hospital wards (OR =2.938, 95% CI =1.339-6.448, P=0.007), hemoglobin level (OR =0.814, 95% CI =0.693-0.956, P=0.012), and systolic blood pressure (OR =0.976, 95% CI =0.955-0.997, P=0.023). Five other factors assessed during hospitalization appear to be associated with pressure ulcer development: mean evening body temperature (OR =3.830, 95% CI =1.729-8.486, P=0.001), mean Waterlow score (OR =1.194, 95% CI =1.092-1.306, P<0.001), the lowest recorded sodium concentration (OR =0.880, 95% CI =0.814-0.951, P=0.001), mean systolic blood pressure (OR =0.956, 95% CI =0.929-0.984, P=0.003), and the lowest recorded hemoglobin level (OR =0.803, 95% CI =0.672-0.960, P=0.016).

CONCLUSION

Hyponatremia and low blood pressure may contribute to the formation of pressure ulcers in patients with an advanced illness.

Cross-Sectional Positive Association of Serum Lipids and Blood Pressure With Serum Sodium Within the Normal Reference Range of 135-145 mmol/L

OBJECTIVE

Serum sodium concentration is maintained by osmoregulation within normal range of 135 to 145 mmol/L. Previous analysis of data from the ARIC study (Atherosclerosis Risk in Communities) showed association of serum sodium with the 10-year risk scores of coronary heart disease and stroke. Current study evaluated the association of within-normal-range serum sodium with cardiovascular risk factors.

APPROACH AND RESULTS

Only participants who did not take cholesterol or blood pressure medications and had sodium within normal 135 to 145 mmol/L range were included (n=8615), and the cohort was stratified based on race, sex, and smoking status. Multiple linear regression analysis of data from ARIC study was performed, with adjustment for age, blood glucose, insulin, glomerular filtration rate, body mass index, waist to hip ratio, and calorie intake. The analysis showed positive associations with sodium of total cholesterol, low-density lipoprotein cholesterol, and total cholesterol to high-density lipoprotein cholesterol ratio; apolipoprotein B; and systolic and diastolic blood pressure. Increases in lipids and blood pressure associated with 10 mmol/L increase in sodium are similar to the increases associated with 7 to 10 years of aging. Analysis of sodium measurements made 3 years apart demonstrated that it is stable within 2 to 3 mmol/L, explaining its association with long-term health outcomes. Furthermore, elevated sodium promoted lipid accumulation in cultured adipocytes, suggesting direct causative effects on lipid metabolism.

CONCLUSIONS

Serum sodium concentration is a cardiovascular risk factor even within the normal reference range. Thus, decreasing sodium to the lower end of the normal range by modification of water and salt intake is a personalizable strategy for decreasing cardiovascular risks.

Hypotonic fluid reduce serum sodium compared to isotonic fluids during anesthesia induction in pediatric patients undergoing maxillofacial surgery-type of infusion affects blood electrolytes and glucose: an observational study

Background

Reportedly, administration of hypotonic fluids containing 30.8–74 mEq/L sodium with 5 % glucose may lead to serious hyponatremia or hyperglycemia. In Japan, hypotonic fluids containing 90 mEq/L sodium with 2.6 % glucose are commonly used. We compared blood electrolyte balance and blood glucose concentration with the use of isotonic (140 mEq/L sodium with 1 % glucose) versus hypotonic fluids in pediatric patients.

Methods

We studied 77 children aged 5 months to 2 years who underwent oro-maxillofacial surgery and dental treatment under general anesthesia. Patients were categorized according to the fluids infused (hypotonic or isotonic). Blood samples were obtained from the dorsalis pedis artery between the conclusion of anesthesia induction and commencement of surgery. We compared blood sodium, potassium and glucose concentrations in the two fluid groups during the pre-anesthesia and post-anesthesia-induction periods.

Results

There were no significant differences in pre-anesthesia values between isotonic (n = 35) and hypotonic groups (n = 42). There were significant differences between isotonic and hypotonic groups in post-anesthesia-induction concentrations of sodium (isotonic, 138.7 ± 1.4 mEq/L; hypotonic, 137.5 ± 1.3 mEq/L; p = 0.0003) and glucose (isotonic, 88.0 ± 9.4 mg/dL; hypotonic, 109.9 ± 18.4 mg/dL; p < 0.0001), while potassium concentrations were not significantly different (isotonic, 4.0 ± 0.3 mEq/L; hypotonic, 4.0 ± 0.2 mEq/L; p = 0.6615) between the two groups.

Conclusion

Isotonic solution administration enables avoidance of serum sodium reduction and serum glucose elevation in infants, and may therefore enhance patient safety in comparison with hypotonic solutions.

Trial registration

University Hospital Medical Information Network Clinical Trials Registry (UMIN000014648), registration 25 July 2014.

Vomiting and Hyponatremia Are Risk Factors for Worse Clinical Outcomes Among Patients Hospitalized Due to Nonsurgical Abdominal Pain: A Retrospective Cohort Study

After initial evaluation in the Emergency Department (ED), many patients complaining of abdominal pain are classified as suffering from nonsurgical abdominal pain (NSAP). Clinical characteristics and risk factors for worse prognosis were not published elsewhere.Characterizing the clinical profile of patients hospitalized due to NSAP and identifying predictor variables for worse clinical outcomes.We made a retrospective cohort analysis of patients hospitalized due to NSAP compared to matched control patients (for age, gender, and Charlson comorbidity index) hospitalized due to other, nonsurgical reasons in a ratio of 1 to 10. We further performed in-group analysis of patients admitted due to NSAP in order to appreciate variables (clinical and laboratory parameters) potentially associated with worse clinical outcomes.Overall 23,584 patients were included, of which 2144 were admitted due to NSAP and 21,440 were matched controls. Patients admitted due to NSAP had overall better clinical outcomes: they had lower rates of in-hospital and 30-days mortality (2.8% vs 5.5% and 7.9% vs 10.4% respectively, P < 0.001 for both comparisons). They also had a significantly shorter length of hospital stay (3.9 vs 6.2 days, P < 0.001). Rates of re-hospitalization within 30-days were not significantly different between study groups. Among patients hospitalized due to NSAP, we found that vomiting or hyponatremia at presentation or during hospital stay were associated with worse clinical outcomes.Compared to patients hospitalized due to other, nonsurgical reasons, the overall prognosis of patients admitted due to NSAP is favorable. The combination of NSAP with vomiting and hyponatremia is associated with worse clinical outcomes.

Hyponatremia in the general population. What does it mean?

Hyponatremia is a frequent problem in clinical practice and is known to be associated with a variety of serious adverse outcomes. Estimates from the US general population and several community-based cohorts indicate that hyponatremia is also relatively common in these settings, especially among seniors, individuals with underlying disease, and those taking a variety of prescription medications. Prevalence is greatly increased when persons with a "low normal" level of serum sodium are considered. Population-based studies have identified a U-shaped relationship between serum sodium and all-cause mortality, with the increased risk at the lower end of the distribution being seen in persons with a "low normal" level of serum sodium as well as those meeting the traditional definition of hyponatremia. The hyponatremia associated risk in epidemiologic studies is of lesser magnitude than in hospital-based studies but of great potential importance give the much larger number of persons with a low serum sodium in the general population. An important challenge for the research community is to determine whether low levels of serum sodium are a direct cause of increased risk. Population-based studies are likely to provide the best opportunity to resolve this question.