Hyponatremia Demystified: Integrating Physiology to Shape Clinical Practice

Hyponatremia is one of the most common problems encountered in clinical practice and one of the least-understood because accurate diagnosis and management require some familiarity with water homeostasis physiology, making the topic seemingly complex. The prevalence of hyponatremia depends on the nature of the population studied and the criteria used to define it. Hyponatremia is associated with poor outcomes including increased mortality and morbidity. The pathogenesis of hypotonic hyponatremia involves the accumulation of electrolyte-free water caused by either increased intake and/or decrease in kidney excretion. Plasma osmolality, urine osmolality, and urine sodium can help to differentiate among the different etiologies. Brain adaptation to plasma hypotonicity consisting of solute extrusion to mitigate further water influx into brain cells best explains the clinical manifestations of hyponatremia. Acute hyponatremia has an onset within 48 hours, commonly resulting in severe symptoms, while chronic hyponatremia develops over 48 hours and usually is pauci-symptomatic. However, the latter increases the risk of osmotic demyelination syndrome if hyponatremia is corrected rapidly; therefore, extreme caution must be exercised when correcting plasma sodium. Management strategies depend on the presence of symptoms and the cause of hyponatremia and are discussed in this review.

Emerging Biomarkers for Predicting Clinical Outcomes in Patients with Heart Disease

Cardiovascular disease is most frequently caused by the development and progression of atherosclerosis. When coronary arteries are afflicted, and the stenoses caused by atherosclerotic plaques are severe enough, the metabolic supply-and-offer balance is disturbed, leading to myocardial ischemia. If atherosclerotic plaques become unstable and local thrombosis develops, a myocardial infarction occurs. Sometimes, myocardial ischemia and infarction may result in significant and irreversible heart failure. To prevent severe complications, such as acute coronary syndromes and ischemia-related heart failure, extensive efforts have been made for developing biomarkers that would help identify patients at increased risk for cardiovascular events. In this two-part study, we attempted to provide a review of existing knowledge of blood biomarkers that may be used in this setting. The first part of this work was dedicated to conventional biomarkers, which are already used in clinical practice. In the second part, here presented, we discuss emerging biomarkers which have not yet become mainstream.

Study on the risk of coronary heart disease in middle-aged and young people based on machine learning methods: a retrospective cohort study

Objective

To identify coronary heart disease risk factors in young and middle-aged persons and develop a tailored risk prediction model.

Methods

A retrospective cohort study was used in this research. From January 2017 to January 2020, 553 patients in the Department of Cardiology at a tertiary hospital in Anhui Province were chosen as research subjects. The research subjects were separated into two groups based on the results of coronary angiography performed during hospitalization (n = 201) and non-coronary heart disease (n = 352). R software (R 3.6.1) was used to analyze the clinical data of the two groups. A logistic regression prediction model and three machine learning models, including BP neural network, Extreme gradient boosting (XGBoost), and random forest, were built, and the best prediction model was chosen based on the relevant parameters of the different machine learning models.

Results

Univariate analysis identified a total of 24 indexes with statistically significant differences between coronary heart disease and non-coronary heart disease groups, which were incorporated in the logistic regression model and three machine learning models. The AUCs of the test set in the logistic regression prediction model, BP neural network model, random forest model, and XGBoost model were 0.829, 0.795, 0.928, and 0.940, respectively, and the F1 scores were 0.634, 0.606, 0.846, and 0.887, indicating that the XGBoost model's prediction value was the best.

Conclusion

The XGBoost model, which is based on coronary heart disease risk factors in young and middle-aged people, has a high risk prediction efficiency for coronary heart disease in young and middle-aged people and can help clinical medical staff screen young and middle-aged people at high risk of coronary heart disease in clinical practice.

Impact of Sodium Levels on Functional Outcomes in Patients With Stroke - A Swiss Stroke Registry Analysis

CONTEXT

Correction of hyponatremia might represent an additional treatment for improving stroke patients' clinical outcomes.

OBJECTIVE

Admission hyponatremia is associated with worse clinical outcome in stroke patients, but whether normalization of hyponatremia improves outcome is unknown. We investigated whether normalization of hyponatremia affects patients' disability, mortality, and stroke recurrence within 3 months; length of hospitalization; and discharge destination.

DESIGN

This was a registry-based analysis of data collected between January 2016 and December 2018. We linked data from Swiss Stroke Registry (SSR) with electronic patients' records for extracting sodium values.

SETTING

We analyzed data of hospitalized patients treated at University Hospital of Basel.

PATIENTS

Stroke patients whose data and informed consent were available.

MAIN OUTCOME MEASURE

Modified Rankin Scale (mRS) score at 3 months. The tested hypothesis was formulated after SSR data collection but before linkage with electronic patients' records.

RESULTS

Of 1995 patients, 144 (7.2%) had hyponatremia on admission; 102 (70.8%) reached normonatremia, and 42 (29.2%) remained hyponatremic at discharge. An increase of initial sodium was associated with better functional outcome at 3 months (odds ratio [OR] 0.94; 95% CI, 0.90-0.99, for a shift to higher mRS per 1 mmol/L sodium increase). Compared with normonatremic patients, patients who remained hyponatremic at discharge had a worse functional outcome at 3 months (odds ratio 2.46; 95% CI, 1.20-5.03, for a shift to higher mRS). No effect was found on mortality, recurrence, or length of hospitalization.

CONCLUSIONS

In hospitalized acute stroke patients, persistent hyponatremia is associated with worse functional outcome. Whether active correction of hyponatremia improves outcome remains to be determined in prospective studies.

The Effects of Curcumin Plus Piperine Supplementation in Patients with Acute Myocardial Infarction: A Randomized, Double-Blind, and Placebo-Controlled Trial

BACKGROUND

Acute myocardial infarction (AMI) is a leading cause of death and disability worldwide. Previous investigations have demonstrated that curcumin has a cardioprotective effect and may improve myocardial injury. So this study was performed to assess whether supplementation with curcumin could diminish myocardial injury following AMI.

METHODS

To conduct this randomized, double-blinded, and placebo-controlled clinical trial, seventy-two patients with acute myocardial infarction, aged 18-75 years, were enrolled and randomly divided into the active intervention and control groups. The active intervention group (n = 38) received curcumin capsules with piperine supplement (500 mg/day, 95% curcuminoids) for 8 weeks, whereas the control group (n = 34) received a placebo capsule. At the baseline and end of the study, ejection fraction was assessed, and blood samples were taken from all patients to measure the levels of cardiac troponin I(cTnI), lipid profile, FBG, HbA1C, liver enzymes, renal function parameters, and electrolytes.

RESULTS

In this trial, curcumin supplementation significantly reduced the levels of HbA1C (-0.3 ± 2.2 vs. +1.1 ± 1.3, P = 0.002), LDL (-10.3 ± 20.7 vs. +0.2 ± 22.5, P = 0.039), ALT (-10.2 ± 28.5 vs. +7.3 ± 39.2, P = 0.029), and ALP (+6.4 ± 39.5 vs. +38.0 ± 69.0, P = 0.018) compared to the placebo group. Moreover, the serum concentration of HDL significantly improved in comparison with the placebo group (+4.5 ± 8.9 vs. -1.6 ± 7.7, P = 0.002). However, no substantial difference was perceived between the groups regarding the ejection fraction and serum levels of cTnI, FBG, renal function parameters, and electrolytes.

CONCLUSION

Our results indicated that daily intake of 500 mg of curcumin capsules with piperine supplement for 8 weeks modified lipid profile, liver enzymes, and glycemic status, but did not have any effect on ejection fraction and serum concentration of cardiac troponin I, renal function parameters, and electrolytes in acute myocardial infarction patients.

Hyponatremia Intervention Trial (HIT): Study Protocol of a Randomized, Controlled, Parallel-Group Trial With Blinded Outcome Assessment

Background: Hyponatremia is the most common electrolyte disorder with a prevalence of up to 30% in hospitalized patients. In contrast to acute hyponatremia where the need for immediate treatment is well-recognized, chronic hyponatremia is often considered not clinically relevant. This is illustrated by reports showing that appropriate laboratory tests are ordered in <50% of patients and that up to 75% are still hyponatremic at discharge. At the same time, emerging evidence suggests an association between hyponatremia and adverse events including increased risk of mortality and rehospitalization. Methods: This is a randomized (1:1 ratio) controlled, superiority, parallel-group international multi-center trial with blinded outcome assessment. In total 2,278 participants will be enrolled. Participants will be randomly assigned to undergo either targeted correction of plasma sodium levels or standard of care during hospitalization. The primary outcome is the combined risk of death or re-hospitalization within 30 days. Discussion: All data on hyponatremia and mortality are derived from observational studies and often lack methodologic robustness. Consequently, the direct impact of hyponatremia on mortality and rehospitalization risk is still debated, resulting in a clinical equipoise whether in-hospital chronic hyponatremia should be treated or not. Therefore, a randomized controlled trial is required to study whether targeted plasma sodium correction reduces the risk of mortality and rehospitalization associated with hyponatremia. Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT03557957.

Association of Acidemia With Short-Term Mortality of Acute Myocardial Infarction: A Retrospective Study Base on MIMIC-III Database

Acute myocardial infarction (AMI) is a leading cause of death and not a few of these patients are combined with acidemia. This study aimed to detect the association of acidemia with short-term mortality of AMI patients. A total of 972 AMI patients were selected from the Medical Information Mart for Intensive Care (MIMIC) III database for analysis. Propensity-score matching (PSM) was used to reduce the imbalance. Kaplan-Meier survival analysis was used to compare the mortality, and Cox-proportional hazards model was used to detect related factors associated with mortality. After PSM, a total of 345 non-acidemia patients and 345 matched acidemia patients were included. The non-acidemia patients had a significantly lower 30-day mortality (20.0% vs. 28.7%) and lower 90-day mortality (24.9% vs. 31.9%) than the acidemia patients (P < 0.001 for all). The severe-acidemia patients (PH < 7.25) had the highest 30-day mortality (52.6%) and 90-day mortality (53.9%) than non-acidemia patients and mild-acidemia (7.25 ≤ PH < 7.35) patients (P < 0.001). In Cox-proportional hazards model, acidemia was associated with improved 30-day mortality (HR = 1.518; 95%CI = 1.110-2.076, P = 0.009) and 90-day mortality (HR = 1.378; 95%CI = 1.034 -1.837, P = 0.029). These results suggest that severe acidemia is associated with improved 30-day mortality and 90-day mortality of AMI patients.

Serum sodium and eplerenone use in patients with a myocardial infarction and left ventricular dysfunction or heart failure: insights from the EPHESUS trial

BACKGROUND

Sodium changes are common in myocardial infarction (MI) complicated with left ventricular systolic dysfunction (LVSD) and/or heart failure (HF). Sodium handling is fine-tuned in the distal nephron, were eplerenone exhibits some of its pleotropic effects. Little is known about the effect of eplerenone on serum sodium and the prognostic relevance of sodium alterations in patients with MI complicated with LVSD and/or HF.

METHODS

The EPHESUS trial randomized 6632 patients to either eplerenone or placebo. Hyponatremia and hypernatremia were defined as sodium < 135 mmol/L or > 145 mmol/L, respectively. Linear mixed models and time updated Cox regression analysis were used to determine the effect of eplerenone on sodium changes and the prognostic importance of sodium changes, respectively. The primary outcomes were all-cause mortality and a composite of cardiovascular (CV) mortality and CV-hospitalization.

RESULTS

A total of 6221 patients had a post-baseline sodium measurement, 797 patients developed hyponatremia (mean of 0.2 events/per patient) and 1476 developed hypernatremia (mean of 0.4 events/per patient). Patients assigned to eplerenone had a lower mean serum sodium over the follow-up (140 vs 141 mmol/L; p < 0.0001) and more often developed hyponatremia episodes (15 vs 11% p = 0.0001) and less often hypernatremia episodes (22 vs. 26% p = 0.0003). Hyponatremia, but not hypernatremia was associated with adverse outcome for all outcome endpoints in the placebo group but not in the eplerenone group (interaction p value < 0.05 for all). Baseline sodium values did not influence the treatment effect of eplerenone in reducing the various endpoints (interaction p value > 0.05 for all). Development of new-onset hyponatremia following eplerenone initiation did not diminish the beneficial eplerenone treatment effect.

CONCLUSION

Eplerenone induces minor reductions in serum sodium. The beneficial effect of eplerenone was maintained regardless of the baseline serum sodium or the development of hyponatremia. Sodium alterations should not refrain clinicians from prescribing eplerenone to patients who had an MI complicated with LVSD and/or HF.

TRAIL REGISTRY

ClinicalTrials.gov identifier: NCT00232180. Serum sodium and eplerenone use in patients with a myocardial infarction and left ventricular dysfunction or heart failure: insights from the EPHESUS trial.

Potassium variability during hospitalization and outcomes after discharge in patients with acute myocardial infarction

BACKGROUND

The variability of metabolic biomarkers has been determined to provide incremental prognosis information, but the implications of electrolyte variability remained unclear.

METHODS

We investigate the relationships between electrolyte fluctuation and outcomes in survivors of acute myocardial infarction (n = 4386). Ion variability was calculated as the coefficient of variation, standard deviation, variability independent of the mean (VIM) and range. Hazard ratios (HR) were estimated using the multivariable-adjusted Cox proportional regression method.

RESULTS

During a median follow-up of 12 months, 161 (3.7%) patients died, and heart failure occurred in 550 (12.5%) participants after discharge, respectively. Compared with the bottom quartile, the highest quartile potassium VIM was associated with increased risks of all-cause mortality (HR = 2.35, 95% CI: 1.36-4.06) and heart failure (HR = 1.32, 95% CI: 1.01-1.72) independent of cardiac troponin I (cTnI), N terminal pro B type natriuretic peptide (NT-proBNP), infarction site, mean potassium and other traditional factors, while those associations across sodium VIM quartiles were insignificant. Similar trend remains across the strata of variability by other three indices. These associations were consistent after excluding patients with any extreme electrolyte value and diuretic use.

CONCLUSIONS

Higher potassium variability but not sodium variability was associated with adverse outcomes post-infarction. Our findings highlight that potassium variability remains a robust risk factor for mortality regardless of clinical dysnatraemia and dyskalaemia.

Prognostic Significance of Hyponatremia in ST-elevation Myocardial Infarction/Heart Failure Patients

ST-elevation myocardial infarction (STEMI) and heart failure (HF) are common, big-budget, debilitating and expanding diseases. Cardiovascular diseases, especially STEMI and heart failure have been known to cause 17.3 million deaths worldwide annually. Hyponatremia, delineated as a serum sodium (sNa) concentration <135 mmol/l, is a frequently seen electrolyte disturbance in practice and the prevalence, clinical impact; the prognostic factor of low SNa in STEMI/heart failure patients vary widely. The aim of this review is to assess its existence and comparing survival difference between hypo and normonatremic patients.

A comprehensive review of the published articles was conducted using database PubMed. We found a total of over 1400 articles. The inclusion criteria used for this review were age >65 years, published within the last 10 years, written in English, performed on human subjects and of studies such as reviews and randomized controlled trials (RCTs), especially for heart failure MeSH words. By applying this inclusion criterion, we found out 40 relevant articles which included 26 cohort studies, four clinical trials, four review articles, and six RCTs. In the analysis of 7,06,899 patients with STEMI/heart failure, hyponatremia was significantly linked to causing all-cause mortality, both short and long term (hazard ratio [HR] as continuous variable: 1.06; 95% confidence interval [CI]: 1.01-1.11; P = 0.026; HR as categorical variable: 1.71; 95% CI: 1.06-2.75; P = 0.028). The rates of rehospitalization were also higher (odds ratio, 1.68; 95% confidence interval, 1.32-2.14) along with prolonged hospital stays as well as a greater cost burden as compared to patients with normal serum sodium. It was existent not only in patients with reduced ejection fraction (HFrEF) but also in subjects with preserved ejection fraction (HFpEF) (HR 1.40, 95% CI 1.12 to 1.75, P = 0.004). Rise of first follow-up and discharge sodium does seem to have positive linkage on survival as well (hazard ratio [HR] 0.429, 95% CI 0.191-0.960, P = 0.04).

Hyponatremia is the most frequently encountered electrolyte abnormality in clinical practice and has a poor prognosis in both STEMI and heart failure patients. It exacerbates both short and long term mortality, rehospitalization rates, as well as the average length of stay in the hospital. Although it is still a mystery whether hyponatremia is just a marker of iller patients or the core of poor prognosis in patients with STEMI and HF, one thing is certain: timely recognition of patients at risk for developing hyponatremia could help to commence early treatment.

Impact of chronic hyponatremia on neurocognitive and neuromuscular function

BACKGROUND

Chronic hyponatremia is common and associated with increased morbidity and mortality. However, whether treatment improves outcome in patients without significant symptoms is unclear. We here assessed the therapeutic outcome on clinical symptoms, neurocognitive and neuromuscular function in patients with chronic non profound hyponatremia.

MATERIAL AND METHODS

Prospective case-control study in 19 patients from the University Hospital Würzburg with chronic non profound hyponatremia without clinically apparent symptoms. At baseline and after a 14-day treatment period of hyponatremia, patients were assessed by specific clinical symptoms questionnaire, neurocognitive and neuromuscular function was analysed by five attention tests and a gait test consisting of 3 steps "in tandem." The results were compared to a control group of healthy volunteers.

RESULTS

Compared to healthy volunteers, patients with mild (n = 10, mean serum sodium 132 ± 1.2 mmol/L) and moderate hyponatremia (n = 9, mean 126 ± 3.3 mmol/L) performed significantly worse in the neurocognitive subtests alertness (P = 0.018), divided attention (P = 0.017) and go/no-go (P = 0.026). Performance in the neuromuscular subtests was also lower in the patient group without reaching significance. The extent of hyponatremia had no impact on the specific test and questionnaire results. Fourteen-day treatment of hyponatremia improved clinical symptoms in all patients (P = 0.003) and neurocognitive function in sodium-normalised patients (go/no-go test, P = 0.029).

CONCLUSION

Chronic hyponatremia is symptomatic and impairs neurocognitive and neuromuscular function. Short-time therapeutic intervention led to improved clinical symptoms and neurocognitive function, but had no effect on neuromuscular function. Larger trials with long-term treatment are needed to specify the therapeutic need in chronic hyponatremia.

Efficacy of serum blood urea nitrogen, creatinine and electrolytes in the diagnosis and mortality risk assessment of patients with acute coronary syndrome

BACKGROUND

Although blood urea nitrogen (BUN), creatinine (Cr) and electrolytes are not the mainstay of diagnosis in acute coronary syndrome (ACS) patients but they may have a role in providing a more detailed view of the complications and mortality rates. The aim of this study was to determine the efficacy of these parameters in the diagnosis and mortality risk-assessment of patients with ACS.

METHODOLOGY

A total of 200 patients with ACS were recruited in this prospective study. The relationship of serum BUN, Cr and electrolytes with cardiac enzymes, Global Registry of Acute Coronary Events (GRACE) and mortality was assessed during a 6-months follow-up. Statistical test like multivariate linear regression and binary logistic regression analysis were applied.

RESULTS

On multivariate linear regression analysis, serum potassium (K) (Unstandardized Coefficient B=-3.77; p=0.04) showed significant negative association with Creatine Kinease and serum BUN (Unstandardized Coefficient B=0.52; p=0.001) showed significant positive association with Troponin I. The patients with GRACE>105 had significantly higher levels of serum BUN and Cr. Receiver operating characteristic curves showed that area under curve (AUC) of BUN (0.7) was higher than AUC of Cr (0.5). Multiple adjusted model showed that patients with BUN>32.5mg/dl were almost 20 times more likely to be associated with mortality as compared to reference group.

CONCLUSION

In addition to cardiac enzymes, K along with BUN and Cr may serve as important aid in diagnosis of ACS. BUN and Cr may also serve as important tools in mortality-risk assessment of ACS patients.

Short- and long-term prognostic value of hyponatremia in patients with acute coronary syndrome: A systematic review and meta-analysis

Hyponatremia is relevant to heart failure, liver cirrhosis and stroke, but the prognostic value of serum sodium levels in patients with acute coronary syndrome are still unclear. So we did a systematic review and meta-analysis to assess the prognostic value of hyponatremia on adverse events in patients after ACS. We systematically searched PubMed, Embase and Cochrane Library to find literatures which studied the prognostic value of hyponatremia in patients with ACS. Our main endpoints were the all-cause mortality and heart failure in the short- and long-term. Of 369 identified studies, 20 studies were included in our analysis. Compared with the normal natrium, hyponatremia was significantly associated with the increased risks of all-cause mortality within 30 days (RR: 2.18; 95%CI: 1.96–2.42) and during the follow-ups (HR: 1.74; 95%CI: 1.56–1.942). For the second endpoint of short- and long-term heart failure, the pooled effect sizes in hyponatremia patients were 1.72(95%CI: 1.38–2.14) and 1.69(95%CI: 1.12–2.55) respectively. In conclusion, hyponatremia has a significant prognostic value for short- and long-term adverse event in patients after ACS, the dynamic monitoring of serum sodium levels may could help physicians to identify high risk ACS patients and to stratify risk for optimal management.

Sodium levels on admission are associated with mortality risk in hospitalized patients

AIMS

Abnormal sodium values are common among hospitalized patients. We aimed to investigate the association of admission sodium values and mortality.

METHODS

Historical prospectively data of adult patients hospitalized to medical wards between January 2011 and December 2013. Admission sodium values were classified to five categories: severe hyponatremia (<125mEq/L), mild hyponatremia (125-135mEq/L), normal sodium values (135-145mEq/L), mild hypernatremia (145-150mEq/L) and severe hypernatremia (>150mEq/L). Main outcomes were length of hospitalization, in-hospital mortality and mortality at the end-of-follow-up.

RESULTS

The cohort included 27,889 patients (mean age 67±18years, 52% males). The total follow-up was 1065days. Most patients had normal sodium values (76%), 22% had hyponatremia, 3% had hypernatremia. Mean age increased with increase in severity of hyponatremia or hypernatremia. Median length of hospitalization was longer with mild and severe hypernatremia (7 and 5days, respectively) or with mild and severe hyponatremia (4 and 4days, respectively), compared to normal sodium levels (3days). Compared to in-hospital mortality with normal sodium levels (5%), mortality was higher with mild and severe hyponatremia (9% and 14%, respectively) and was highest with mild (28%), and severe hypernatremia (52%). Mortality rate at the end of follow-up was 28% with normal sodium levels, 44% and 48% with mild and severe hyponatremia, 66% and 90% with mild and severe hypernatremia, respectively.

CONCLUSIONS

Abnormal sodium values on admission were associated with longer hospitalization and increased short- and long-term mortality. Mortality risk was higher with hypernatremia, compared to hyponatremia.

Prognostic impact of hyponatremia occurring at various time points during hospitalization on mortality in patients with acute myocardial infarction

We investigated the incidence and prognostic impact of hyponatremia occurring at various time points during hospitalization on long-term mortality in acute myocardial infarction (AMI) survivors. We retrospectively studied 1863 patients diagnosed with AMI. Baseline, nadir, and discharge sodium levels during hospitalization were recorded and analyzed. Hyponatremia was defined as a serum sodium level <135 mEq/L. On the basis of baseline, nadir, and discharge sodium levels during hospitalization, hyponatremia was diagnosed in 309 (16.6%), 518 (27.8%), and 147 (7.9%) patients, respectively. In a multivariate Cox-proportional regression analysis, discharge sodium level had the strongest significant relationship with long-term mortality (hazard ratio [HR] as continuous variable = 1.06, 95% confidence interval [CI]: 1.01-1.11, P = .026; HR as categorical variable = 1.71; 95% CI: 1.06-2.75; P = .028), but baseline and nadir sodium had no prognostic impact on long-term mortality after adjustment. The serum sodium level and incidence of hyponatremia varied at different time points during hospitalization. In addition, the association between sodium level and long-term mortality differed at these various time points. The discharge sodium level, among the various time points, seems the best predictor of long-term mortality in AMI survivors.

Serum Chloride and Sodium Interplay in Patients With Acute Myocardial Infarction and Heart Failure With Reduced Ejection Fraction

Background—

Serum chloride levels were recently found to be independently associated with mortality in heart failure (HF).

Methods and Results—

We investigated the relationship between serum chloride and clinical outcomes in 7195 subjects with acute myocardial infarction complicated by reduced left ventricular function and HF. The studied outcomes were all-cause mortality, cardiovascular mortality, and hospitalization for HF. Both chloride and sodium had a nonlinear association with the studied outcomes ( P <0.05 for linearity). Patients in the lowest chloride tertile (chloride ≤100) were older, had more comorbidities, and had lower sodium levels ( P <0.05 for all). Serum chloride showed a significant interaction with sodium with regard to all studied outcomes ( P for interaction <0.05 for all). The lowest chloride tertile (≤100 mmol/L) was associated with increased mortality rates in the context of lower sodium (≤138 mmol/L; adjusted hazard ratio [95% confidence interval] for all-cause mortality=1.42 (1.14–1.77); P =0.002), whereas in the context of higher sodium levels (>141 mmol/L), the association with mortality was lost. Spline-transformed chloride and its interaction with sodium did not add significant prognostic information on top of other well-established prognostic variables ( P >0.05 for all outcomes).

Conclusions—

In post–myocardial infarction with systolic dysfunction and HF, low serum chloride was associated with mortality (but not hospitalization for HF) in the setting of lower sodium. Overall, chloride and its interaction with sodium did not add clinically relevant prognostic information on top of other well-established prognostic variables. Taken together, these data support an integrated and critical consideration of chloride and sodium interplay.

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.

Association of hyponatremia with in-hospital outcomes in infective endocarditis: A 5-year review from an Indian Intensive Care Unit

Hyponatremia is commonly noted with cardiovascular disorders, but its role in infective endocarditis (IE) is limited to being a marker of increased morbidity in IE patients with intravenous drug use. This was a 5-year retrospective review from an Indian Intensive Care Unit (ICU). Patients >18 years with IE and available serum sodium levels were included in the study. Pediatric and pregnant patients were excluded from the study. Hyponatremia was defined as admission sodium <135 mmol/L. Detailed data were abstracted from the medical records. Primary outcomes were need for invasive mechanical ventilation, ICU length of stay, and in-hospital mortality. Secondary outcomes included development of acute kidney injury, acute decompensated heart failure (ADHF), acute respiratory distress syndrome, stroke, and severe sepsis in the ICU. Two-tailed P < 0.05 was considered statistically significant. Between January 2010 and December 2014, 96 patients with IE were admitted to the ICU with 85 (88.5%) (median age 46 [34.5-55] years, 51 [60.0%] males) meeting our inclusion criteria. The comorbidities, echocardiographic, and microbiological characteristics were comparable between patients with hyponatremia (56; 65.9%) and eunatremia (29; 34.1%). Median sodium in the hyponatremic cohort was 131 mmol/L (127.25-133) compared to the eunatremic cohort 137 mmol/L (135-139) (P < 0.001). The primary outcomes were not different between the two groups. Hyponatremia was associated more commonly with ADHF (12 [21.4%] vs. 0; P = 0.007) during the ICU stay. Hyponatremia is commonly seen in IE patients and is not associated with worse hospital outcomes. ADHF was seen more commonly in the hyponatremic patients in comparison to those with eunatremia.