Higher Serum Sodium Concentrations Research Articles

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

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). 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. 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. 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.

ACUTE EFFECTS OF SODIUM CHLORIDE OR ITS SUBSTITUTE POTASSIUM CHLORIDE ON VASCULAR FUNCTION IN HEALTHY VOLUNTEERS

Objective: High blood pressure, one of the most important risk factors for cardiovascular mortality, leads to vascular dysfunction and subsequently to arteriosclerosis, stroke, kidney and heart failure. High salt intake and low potassium intake are associated with high blood pressure and an increased risk of cardiovascular disease and mortality. Partial replacement of sodium with potassium led to a lower risk of cardiovascular events and death in a long-term follow-up study. However, the exact mechanism remains unclear. Our aim was to investigate the acute effects of sodium or potassium intake on vascular health to unravel the underlying mechanisms leading to vascular adaptations. Design and method: Six male and nine female healthy individuals (mean age 31 years) were randomized to either 9g of sodium chloride (high salt group), 6g of sodium chloride (regular salt group) or 6 g of sodium chloride plus 3g of potassium chloride group (substitution group). Individuals received a salty soup with the corresponding sodium or potassium load. Blood analyses, blood pressure, body composition and macro- as well as microvascular measurements were performed before as well as four (t4) and 24 hours (t24) after soup intake. To investigate macrovascular health, carotid-to-femoral pulse wave velocity was analyzed. Microvascular health was measured by investigating retinal vessel diameters. Results: The high (139±2mmol/l vs. 143±2mmol/l p=0,003) and regular salt group (140±2mmol/l vs. 141±0,6 mmol/l p=0,029) showed both higher serum sodium concentrations at t4 compared to baseline. These higher values were normalized at t24. The serum sodium concentration of the substitution group showed no statistically significant difference between timepoints. The substitution group showed improved microvascular health, quantified by higher arteriolar-to-venular diameter ratio from baseline to t4 (0,86±0,09 vs. 0,89±0,08 p=0,005). These improvements were regressive at t24 (0,88±0,09). No statistically significant changes were found on pulse wave velocity. The high and regular salt group showed no statistically significant differences at any timepoint on micro- or macrovascular health parameters. Conclusions: Replacement of sodium by potassium seems to improve microvascular function directly after potassium intake. These results might explain the long-term beneficial effects of potassium on cardiovascular outcomes.

Serum Sodium Concentration and Increased Risk for Primary Epiretinal Membrane.

Aims: To examine the prevalence of primary epiretinal membranes (ERMs) and associated systemic factors.Methods: The cross-sectional, community-based Tongren Health Care Study enrolled participants who received regular health examinations in the Beijing Tongren Hospital from 2017 to 2019. Using fundus photographs, retinal specialists assessed the presence of ERMs and their systemic associations.Results: Primary ERMs were detected in 841/22820 individuals, with a prevalence of 3.7% [95% confidence intervals (CI): 3.4–3.9%] in the total study population (mean age: 44.5 ± 13.8 years) and 6.5% (95% CI: 6.1–7.0%) in individuals aged 40+ years. In multivariable analysis, a higher ERMs prevalence was associated with older age [odds ratio (OR): 1.10; P < 0.001], higher serum cholesterol concentration (OR: 1.14; P = 0.003) and higher serum sodium concentration (SSC) (OR: 1.12; P < 0.001). In women, a higher SSC, even within the normal range, was associated with an increased risk of ERMs (OR: 1.19; P < 0.001). Female participants with an SSC of 144–145mmol/L as compared with those with an SSC of 135–137 mmol/L had a 5-fold increased odds of having ERMs (All women: OR: 5.33; P < 0.001; Women aged 40+years: OR: 4.63; P < 0.001).Conclusion: Besides older age and higher serum cholesterol concentration, a higher SSC, even if within the normal range, was independently associated with a higher ERM prevalence in women.

Mielinólise pontina: relato de caso

Introdução: A mielinólise pontina central (MPC) e a mielinólise extrapontina (MEP) são agrupadas dentro do contexto de síndromes de desmielinização osmótica as quais são caracterizadas pela dissolução das bainhas de mielina, preservando os axônios. O objetivo deste relato de caso é descrever o relato de caso de paciente com quadro de MPC e realizar a revisão na literatura médica. Detalhamento de caso: Trata-se de uma paciente do sexo feminino, 57 anos, que desenvolveu MPC após rápida correção da hiponatremia secundária a vômitos persistentes. Evolui com síndrome pseudobulbar, tetraparesia, disartria, rebaixamento do nível de consciência e disfagia. Após cinco meses de internação para tratamento sintomático e das complicações inerentes ao seu quadro clínico evoluiu com melhora parcial dos sintomas motores. Discussão: A etiologia da MPC e MEP é multifatorial, com incidência desconhecida e prevalência igual em ambos os sexos, podendo ser encontrada em todas as idades, com elevadas taxas de morbimortalidade. Embora seu principal fator desencadeante seja a correção excessivamente rápida da hiponatremia grave, alguns pacientes podem desenvolvê-la com concentrações séricas de sódio mais elevadas e com menores taxas de correção. O diagnóstico é essencialmente clínico, porém a ressonância magnética é o exame complementar de eleição para confirmação. Os pacientes podem apresentar desde recuperação completa até sequelas neurológicas irreversíveis, não existindo tratamento específico.

Mycobacterium chimaera infection following cardiac surgery in the United Kingdom: clinical features and outcome of the first 30 cases

ObjectivesMycobacterium chimaera infection following cardiac surgery, due to contaminated cardiopulmonary bypass heater–cooler units, has been reported worldwide. However, the spectrum of clinical disease remains poorly understood. To address this, we report the clinical and laboratory features, treatment and outcome of the first 30 UK cases. MethodsCase note review was performed for cases identified retrospectively through outbreak investigations and prospectively through ongoing surveillance. Case definition was Mycobacterium chimaera detected in any clinical specimen, history of cardiothoracic surgery with cardiopulmonary bypass, and compatible clinical presentation. ResultsThirty patients were identified (28 with prosthetic material) exhibiting a spectrum of disease including prosthetic valve endocarditis (14/30), sternal wound infection (2/30), aortic graft infection (4/30) and disseminated (non-cardiac) disease (10/30). Patients presented a median of 14 months post surgery (maximum 5 years) most commonly complaining of fever and weight loss. Investigations frequently revealed lymphopenia, thrombocytopenia, liver cholestasis and non-necrotizing granulomatous inflammation. Diagnostic sensitivity for a single mycobacterial blood culture was 68% but increased if multiple samples were sent. In all, 27 patients started macrolide-based combination treatment and 14 had further surgery. To date, 18 patients have died (60%) a median of 30 months (interquartile range 20–39 months) after initial surgery. Survival analysis identified younger age, mitral valve surgery, mechanical valve replacement, higher serum sodium concentration and lower C-reactive protein as factors associated with better survival. ConclusionsMycobacterium chimaera infection following cardiac surgery is associated with a wide spectrum of disease. The diagnosis should be considered in all patients who develop an unexplained illness following cardiac surgery.

Neutrophil-to-Lymphocyte Ratio Predicts Overall Survival of Advanced Non-Small Cell Lung Cancer Harboring Mutant Epidermal Growth Factor Receptor.

BackgroundNeutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) have been demonstrated to be prognostic biomarkers in various cancers, including non-small cell lung cancer (NSCLC). However, little has been known about these two ratios for a specific population of NSCLC harboring active epidermal growth factor receptor (EGFR) mutation.MethodsWe retrospectively reviewed electrical medical records of 152 patients who met the following criteria: NSCLC harboring mutant EGFR, EGFR-tyrosine kinase inhibitor (EGFR-TKI) monotherapy initiated between October 2007 and February 2017 at our hospital, stage III-IV or post-surgical recurrence. We compared overall survival (OS) and progression-free survival (PFS) between dichotomized groups by the optimal cut-off points of the two biomarkers. Univariate and multivariate Cox hazard analyses also searched for prognostic factors of survival time.ResultsOSs of NLR < 2.11 (median 38.6 vs. 24.1 months, P < 0.01) and LMR ≥ 5.09 (median 39.4 vs. 26.4 months, P < 0.01) were significantly longer than those of NLR ≥ 2.11 and LMR < 5.09. Multivariate analyses found lower NLR (hazard ratio (HR) 1.07, 95% CI: 1.01 - 1.14; P = 0.03) as an independent prognostic factor for longer OS, in addition to Eastern Cooperative Oncology Group performance status 0 - 1, first-line EGFR-TKI, higher serum sodium concentration and lower lactate dehydrogenase. However, LMR was not detected as a significant prognostic factor for OS. None of these two biomarkers was selected as an independent prognostic factor for PFS.ConclusionsThis study demonstrated that elevated NLR is an independent prognostic factor for poor survival of patients with EGFR mutant NSCLC. NLR is a useful and simple biomarker for these patients.

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As Dr. Russo highlights, we found serum sodium, at the date of listing for liver transplantation and at any time while on the wait list, to be strongly associated with wait-list mortality, independent of the MELD score.1 For a serum sodium <126 mEq/L at any point while on the wait list, the lowest excess risk consistent with our results was 2.9 times that of those with higher serum sodium concentrations (hazard ratio of 6.26, 95% CI 2.92-13.4). Serum sodium as a continuous variable also had a significant association with wait-list mortality with 7% increase risk of wait-list mortality for each unit decrease in listing serum sodium. Heuman et al. found that the association with serum sodium and wait-list mortality was limited to patients with MELD <21.2 When we examined the effect of different MELD scores (<16, 16-30, and >30) on strength of association between the serum sodium and wait-list mortality, serum sodium as a continuous variable and as a dichotomous variable (< or ≤126 and > or ≥131), at listing and at any time point, the serum sodium variables were statistically significant across the spectrum of MELD scores. There was no specific cutoff MELD score identifiable that resulted in loss of statistical significance of serum sodium as a predictor of mortality. Logistic regression models provided another way to evaluate the association between hyponatremia and wait-list mortality at 3 and 6 months. In comparison to MELD alone, the addition of serum sodium <126 mEq/L as a dichotomous variable plus MELD led to an increase of the accuracy (c-statistic) of predicting 3- and 6-month wait-list mortality by 3.4% (from 0.883 to 0.917) and 5% (from 0.871 to 0.921), respectively. The estimated incremental improvement with the addition of serum sodium to MELD was sizable considering the shift from CTP to MELD for organ allocation was largely based on a 7% change in the c-statistic (from 0.76 to 0.83) reported by Wiesner et al.3 Russo indicates that the P values comparing ROC curves for MELD alone versus MELD plus serum sodium did not achieve statistical significance. This is true, but the c-statistic represents only one way to assess for significance. The uniform increase in area under the ROC curves (c-statistic) with the additional of serum sodium to the model and the significant increase in odds ratios in the logistic regression models are indicative of a significant independent impact of serum sodium predicting wait-list mortality. Moreover, an equally important measure of the statistical significance of the adding serum sodium to MELD is reflected by the 95% confidence intervals for the bivariate logistic regression models that generate the ROC curves. These results showed that the increase in odds of 3- and 6-month wait-list mortality, controlling for MELD score, was at least 4% and 5%, respectively, for each unit decrease in listing serum sodium concentration. Russo comments that the model by Heumann et al. is more “encouraging,” possibly because the findings of that study are in keeping with his clinical intuition. However, our conclusions that serum sodium adds to MELD in predicting wait-list mortality is strongly supported by the survival analyses and logistic regression models. Clearly, in the future, we look toward confirmation and extension of our findings in larger, multicenter databases. With UNOS currently collecting serum sodium values, we anticipate such studies will be forthcoming in the very near future. Scott Biggins M.D.*, Norah Terrault M.D., M.P.H.*, * University of California San Francisco, San Francisco, CA

Weight changes, medical complications, and performance during an Ironman triathlon

Background: Subjects exercising without fluid ingestion in desert heat terminated exercise when the total loss in body weight exceeded 7%. It is not known if athletes competing in cooler conditions...

Analysis of determinants of ventricular fibrillation induced by reperfusion: Dissociation between electrical instability and myocardial damage

To assess the underlying mechanisms of ventricular fibrillation induced by myocardial reperfusion after cardioplegic arrest, 62 patients undergoing an open heart operation were divided into two groups based on the absence (group 1, n = 37) or the development (group 2, n = 25) of reperfusion-induced ventricular fibrillation. There was no close relationship between the incidence of reperfusion-induced ventricular fibrillation and aortic clamp time. On reperfusion, the time to onset of cardiac activity was similar in groups 1 (2.4 ± 1.8 minutes) and 2 (1.9 ± 1.1 minutes). At that time, there was no significant difference in values of arterial oxygen and bicarbonate contents, pH, or base excess between the two groups, but myocardial temperature was significantly higher in group 2 (25.6 ° ± 3.4 ° versus 27.6 ° ± 2.4 °C; p < 0.05). In addition, serum levels of sodium (123.9 ± 4.2 versus 126.1 ± 3.7 mmol/L; p < 0.05) and calcium (0.80 ± 0.07 versus 0.84 ± 0.05 mmol/L; p < 0.05) were significantly higher and serum potassium levels (3.98 ± 0.58 versus 3.55 ± 0.61 mmol/L; p < 0.02) and the serum potassium to calcium ratio (4.94 ± 0.90 versus 4.29 ± 0.72; p < 0.01) significantly lower in group 2. Postoperative serum levels of the myocardial-specific isoenzyme of creatine kinase and myoglobin were similar in both groups. By multivariate analysis, shorter ischemic time, higher myocardial temperature, higher serum sodium concentration, and lower serum potassium to calcium ratio were found to influence induction of reperfusion-induced ventricular fibrillation. We conclude that ion imbalance and myocardial temperature, rather than severity of ischemia-related and reperfusion-related myocardial damage, may be important for the genesis of reperfusion-induced ventricular fibrillation and that reperfusion injury, if reperfusion-induced ventricular fibrillation is a representative phenomenon of reperfusion injury, may not be a major cause of postoperative cardiac dysfunction.