Estimation of dietary intake of sodium, potassium, phosphorus and protein in healthy Indian population and patients with chronic kidney disease.

Introduction: Poor nutritious diet is a major risk element for non-communicable diseases (NCD), which are of considerable public health concern. Given the diverse dietary patterns in India, precise determination of nutrient consumption is crucial for disease management. The present study assessed the dietary intake of sodium, potassium, protein, and phosphorus among North Indians. Methods: This cross-sectional study included healthy adults and adults with stage 2 to 4 chronic kidney disease (CKD). We analysed sodium, protein, potassium and phosphorus intakes using one-time 24-h urinary excretion. Dietary intake was also analysed in subgroups based on sex, body mass index, blood pressure and abdominal obesity. We evaluated the performance of various equations available to estimate sodium intake using a spot urine sample with respect to the sodium excretion measured in a 24-h urine sample. Descriptive statistics was used along with t-test for statistical significance. Results: A total of 404 subjects (182 adult healthy subjects and 222 adults with CKD) with a mean age of 47.01 ± 11.46 years were studied. Mean dietary intakes of sodium, salt, potassium, protein and phosphorus were 2.94 ± 1.68 g/day, 7.42 ± 4.24 g/day, 1.43 ± 0.59 g/day, 47.67 ± 14.73 g/day and 0.86 ± 0.39 g/day, respectively. There were no differences in nutrient consumption between adults who were healthy and those with CKD. Consumption of sodium, salt, protein, potassium, and phosphorus among healthy population vs. those with CKD were 2.81 ± 1.60 vs. 3.05 ± 1.73 g/day (p = 0.152), 7.08 ± 4.04 vs. 7.70 ± 4.37 g/day (p = 0.143), 47.16 ± 14.59 vs. 48.08 ± 14.86 g/day (p = 0.532), 1.38 ± 0.59 vs. 1.48 ± 0.58 g/day (p = 0.087) and 0.86 ± 0.41 vs. 0.87 ± 0.37 g/day (p = 0.738), respectively. Men had higher consumption of these nutrients than women. Compared to non-hypertensives, hypertensive subjects had higher consumption of salt (8.23 ± 4.89 vs. 6.84 ± 3.59 g/day, p = 0.002) and potassium (1.51 ± 0.63 vs. 1.38 ± 0.55 g/day, p = 0.024), however, no difference were found in protein and phosphorus intakes. In terms of performance of equations used to estimate 24-h sodium intake from spot urinary sodium concentration against the measured 24-h urinary sodium excretion, INTERSALT 2 equation exhibited the least bias [1.08 (95% CI, -5.50 to 7.66)]. Conclusion: The study shows higher-than-recommended salt and lower-than-recommended potassium intake in the north Indian population compared to those recommended by guidelines. The dietary protein intake is below the recommended dietary allowance. These findings help the development of targeted policies for dietary modification to reduce the risk of the development and progression of CKD.

Exploratory study on the relationship between urinary sodium/potassium ratio, salt intake, and the antihypertensive effect of esaxerenone: the ENaK Study.

Excessive salt intake is one of the causes of hypertension, and reducing salt intake is important for managing the risk of hypertension and subsequent cardiovascular events. Esaxerenone, a mineralocorticoid receptor blocker, has the potential to exert an antihypertensive effect in hypertensive patients with excessive salt intake, but evidence is still lacking, especially in clinical settings. We aimed to determine if baseline sodium/potassium ratio and baseline estimated 24-h urinary sodium excretion can predict the antihypertensive effect of esaxerenone in patients with essential hypertension inadequately controlled with an angiotensin receptor blocker (ARB) or a calcium channel blocker (CCB). This was an exploratory, open-label, interventional study with a 4-week observation period and a 12-week treatment period. Esaxerenone was orally administered once daily in accordance with the Japanese package insert. In total, 126 patients met the eligibility criteria and were enrolled (ARB subcohort, 67; CCB subcohort, 59); all were included in the full analysis set (FAS) and safety analysis. In the FAS, morning home systolic blood pressure (SBP)/diastolic blood pressure (DBP) significantly decreased from baseline to end of treatment (primary efficacy endpoint) (-11.9 ± 10.9/ - 6.4 ± 6.8 mmHg, both p < 0.001); a similar trend was observed in both subcohorts. Significant reductions were also shown in bedtime home and office SBP/DBP (all p < 0.001). Each BP change was consistent regardless of the urinary sodium/potassium ratio or estimated 24-h urinary sodium excretion at baseline. The urinary albumin-creatinine ratio (UACR) and N-terminal pro-brain natriuretic peptide (NT-proBNP) significantly decreased from baseline to Week 12 in the total population and both subcohorts. No new safety concerns were raised. Esaxerenone significantly decreased morning home, bedtime home, and office BP; UACR; and NT-proBNP in this patient population, regardless of concomitant ARB or CCB use. The antihypertensive effect of esaxerenone was independent of the urinary sodium/potassium ratio and estimated 24-h urinary sodium excretion at baseline.

Effects of Behavioral Interventions for Salt Reduction on Blood Pressure and Urinary Sodium Excretion: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Hypertension is a prevalent cardiovascular condition, with excessive sodium intake being a significant risk factor. Various studies have investigated measures to reduce salt intake, including integrated lifestyle interventions and health education. However, the effectiveness of behavioral interventions focused solely on salt reduction remains unclear. This systematic review and meta-analysis aimed to investigate the effects of a behavioral intervention based on salt reduction on blood pressure and urinary sodium excretion. A comprehensive search of the Cochrane Central Register of Controlled Trials, EMBASE, PubMed, and Web of Science was conducted to identify relevant literature. Study and intervention characteristics were extracted for descriptive synthesis, and the quality of the included studies was assessed. A total of 10 studies, comprising 4,667 participants (3,796 adults and 871 children), were included. The interventions involved the provision of salt-restriction spoons or devices, salt-reduction education, self-monitoring devices for urinary sodium, and salt-reduction cooking classes. Meta-analysis results showed that behavioral interventions focused on salt reduction significantly reduced systolic blood pressure (SBP) (-1.17 mmHg; 95% CI, -1.86 to -0.49), diastolic blood pressure (DBP) (-0.58 mmHg; 95% CI, -1.07 to -0.08) and urinary sodium excretion (-21.88 mmol/24 hours; 95% CI, -32.12 to -11.64). These findings suggest that behavioral change interventions centered on salt reduction can effectively lower salt intake levels and decrease blood pressure levels. However, to enhance effectiveness, behavioral interventions for salt reduction should be combined with other salt-reduction strategies.

Characteristics of sodium and water retention in rats with nephrotic syndrome induced by puromycin aminonucleoside.

INTRODUCTION: Nephrotic syndrome (NS) is characterized by renal sodium and water retention. The mechanisms are not fully elucidated. METHODS: The NS rat model was established by single intraperitoneal injection of 100 mg/kg puromycin aminonucleoside (PAN). The plasma electrolyte level and urinary sodium excretion were monitored dynamically. The changes of some sodium transporters, including epithelial Na+ channel (ENaC), Na+/H+ exchanger 3 (NHE3), Na+-K+-2Cl- cotransporter 2 (NKCC2) and Na+-Cl- cotransporter (NCC) in renal cortex at different time points and the level of peripheral circulation factors were detected. RESULTS: The urinary sodium excretion of the model group increased significantly on the first day, then decreased compared with the control group, and there was no significant difference between the model group and the control group on the 12th day. The changes of peripheral circulation factors were not obvious. Some sodium transporters in renal cortex increased in varying degrees, while NKCC2 decreased significantly compared with the control group. CONCLUSIONS: The occurrence of NS edema may not be related to the angiotensin system. The decrease of urinary sodium excretion is independent of the development of albuminuria. During the 18 days of observation, it can be divided into three stages: sodium retention, sodium compensation, and simple water retention. The mechanism is related to the increased expression of α-ENaC, γ-ENaC, NHE3 and NCC in a certain period of time, the compensatory decrease of NKCC2 expression and the continuous increase of aquaporin 2 (AQP2) expression.

Pertinence of Salt-Related Knowledge and Reported Behaviour on Salt Intake in Adults: A Cross-Sectional Study.

The association between salt-related knowledge, attitude, behaviour (KAB) and actual salt consumption in Greek adults is uncertain. This study investigates the correlation between salt intake, gauged by 24-h urinary sodium excretion, with salt-related KAB. It further explores how socio-demographic factors influence these behaviors. Salt consumption was evaluated using a 24-h urinary sodium test, and compared to self-reported KAB data. Knowledge and behavior scores related to salt were computed. An overall cohort-adjusted model examined the relationship between daily salt consumption, knowledge and behavior scores, and certain covariates. Through the stratification by the cohort random effect, two models were established (Cohort I Adults; Cohort II Students) examining the same relationships of the overall cohort model. 463 Greek adults participated. The average salt intake was 9.54 g/day, nearly double the WHO recommendation. Significant differences in knowledge scores were noted based on sex, age, education, and BMI. A trend suggesting lower discretionary salt use with increased salt intake was observed (p = 0.06). However, comprehensive analysis revealed no direct correlation between salt intake and either knowledge (p = 0.562) or behavior scores (p = 0.210). The results emphasize the need for food product reforms by industry stakeholders and accelerated efforts towards reducing salt intake.

O-Linked GlcNAcylation mediates the inhibition of proximal tubule (Na++K+)ATPase activity in the early stage of diabetes mellitus.

BACKGROUND: Diabetic kidney disease (DKD) is a severe complication of diabetes mellitus (DM). It has been proposed that modifications in the function of proximal tubule epithelial cells (PTECs) precede glomerular damage during the onset of DKD. This study aimed to identify modifications in renal sodium handling in the early stage of DM and its molecular mechanism. METHODS: Streptozotocin (STZ)-induced diabetic BALB/c mice (STZ group) and LLC-PK1 cells, a model of PTECs, were used. All parameters were assessed in the 4th week after an initial injection of STZ. RESULTS: Early stage of DKD was characterized by hyperfiltration and PTEC dysfunction. STZ group exhibited increased urinary sodium excretion due to impairment of tubular sodium reabsorption. This was correlated to a decrease in cortical (Na++K+)ATPase (NKA) α1 subunit expression and enzyme activity and an increase in O-GlcNAcylation. RNAseq analysis of patients with DKD revealed an increase in expression of the glutamine-fructose aminotransferase (GFAT) gene, a rate-limiting step of hexosamine biosynthetic pathway, and a decrease in NKA expression. Incubation of LLC-PK1 cells with 10 µM thiamet G, an inhibitor of O-GlcNAcase, reduced the expression and activity of NKA and increased O-GlcNAcylation. Furthermore, 6-diazo-5-oxo-L-norleucine (DON), a GFAT inhibitor, or dapagliflozin, an SGLT2 inhibitor, avoided the inhibitory effect of HG on expression and activity of NKA associated with the decrease in O-GlcNAcylation. CONCLUSION: Our results show that the impairment of tubular sodium reabsorption, in the early stage of DM, is due to SGLT2-mediated HG influx in PTECs, increase in O-GlcNAcylation and reduction in NKA expression and activity.

Does the Mediterranean Dietary Pattern Promote Lower Sodium Urinary Excretion in Children?

An adequate sodium intake is related to various health benefits. Parallelly, the Mediterranean diet (MD) is a dietary pattern known for its many positive impacts on health. Nonetheless, the association between adherence to the MD and sodium urinary excretion is scarce, even more in children. This study aimed to assess the association between MD adherence and the excretion of sodium, as a proxy of intake. This cross-sectional analysis comprised 295 children (46.8% females, aged 7-11 years, mean age: 8.53 ± 0.73 years) from 20 schools within Porto, Portugal. MD adherence was evaluated utilizing the alternate Mediterranean score (aMED). Higher scores denote a healthier dietary pattern (0-8). Sodium excretion was estimated by 24-h urine collection. The association between adherence to MD and Na excretion was estimated by logistic regression, adjusting for confounders. Children in the higher sodium excretion group had a higher intake of legumes, a higher body mass index and parents with lower education levels compared to children in the lower sodium excretion group. In logistic regression analysis, sodium urinary excretion was not associated with higher MD adherence, even after adjustment for confounders. High MD adherence could not be associated with lower sodium excretion in children.

Is a spot urine sample a good substitution to estimate 24-h urinary sodium excretion in a population ≥ 50 years old? A validation study.

PURPOSE: A variety of prediction equations have been able to estimate 24-h urinary sodium excretion from spot urine samples; however, Iranians over the age of 50 have not been compared and verified. Using spot urine samples as a substitute for 24-h urine samples to estimate 24-h urine sodium excretion among the population age 50 and older are the purpose of this study. METHODS: A 24-h urinary sodium excretion was studied by well-known Kawasaki, INTERSALT, Tanaka, and World Health Organization/Pan American Health Organization (WHO/PAHO) formulas. On 360 individuals, the mean bias, agreements between estimated and measured values, correlation, absolute and relative differences, and misclassification rates were evaluated for four equations. RESULTS: As a result, the mean urinary sodium excretion for a 24-h period was 136.3 ± 52.21 mmol/24-h, which corresponds to a calculated intake of 9.1 ± 3.8 g of salt per day. According to the WHO/PAHO formula, the mean bias between measured values and estimated 24-h urinary sodium excretion is - 21.6 mg/day (95% confidence interval (CI) - 144.8, 101.6 mg/day), which is the smallest difference compared with the other three formulas. The lowest rate of individual misclassification of salt intake was 40% for WHO/PAHO, especially for those who consumed less than 9 g/day, while Kawasaki had the lowest misclassification rate at higher levels of salt intake. CONCLUSION: As a result of our research, the WHO/PAHO equations accurately predict 24-h urinary sodium excretion among Iranians aged ≥ 50 more than other equations, both at the population level and at the individual level. However, further study is needed in regard to different ages in Iran.

Awareness and Use of Low-Sodium Salt Substitutes and Its Impact on 24-h Urinary Sodium and Potassium Excretion in China-A Cross-Sectional Study.

The use of low-sodium salt substitute (LSSS) has the potential to reduce sodium and increase potassium intake. LSSS has been available in the Chinese market for years. However, its real-world use and impact on sodium/potassium intake is unclear. Baseline data of 4000 adult individuals who participated in three similarly designed randomized controlled trials were pooled together for this analysis. Self-reported awareness and use of LSSS were collected using a standardized questionnaire, and the participants' 24-h urinary sodium and potassium excretion was used to estimate their dietary intake. Mixed-effects models were developed to assess the relationship between LSSS and 24-h urinary sodium and potassium excretion. 32.0% of the participants reported awareness of LSSS and 11.7% reported its current use. After adjusting for location, sex, age, and education, compared with the group of participants unaware of LSSS, participants who were aware of but not using LSSS and those who were using LSSS had a lower 24-h urinary sodium excretion by -356.1 (95% CI: -503.9, -205.9) mg/d and -490.6 (95% CI: -679.2, -293.7) mg/d, respectively (p < 0.001). No significant difference was found for 24-h urinary potassium excretion or sodium-to-potassium ratio among the three groups (p > 0.05). In conclusion, the findings of low usage of LSSS and the reduced urinary sodium excretion associated with the awareness and use of LSSS provide further support for the prometon of LSSS as a key salt reduction strategy in China.

Proteinuria Modifies the Relationship Between Urinary Sodium Excretion and Adverse Kidney Outcomes: Findings From KNOW-CKD.

Introduction: High sodium intake is associated with increased proteinuria. Herein, we investigated whether proteinuria could modify the association between urinary sodium excretion and adverse kidney outcomes in patients with chronic kidney disease (CKD). Methods: In this prospective observational cohort study, we included 967 participants with CKD stages G1 to G5 between 2011 and 2016, who measured 24-hour urinary sodium and protein excretion at baseline. The main predictors were urinary sodium and protein excretion levels. The primary outcome was CKD progression, which was defined as a ≥50% decline in the estimated glomerular filtration rate (eGFR) or the onset of kidney replacement therapy. Results: During a median follow-up period of 4.1 years, the primary outcome events occurred in 287 participants (29.7%). There was a significant interaction between proteinuria and sodium excretion for the primary outcome (P = 0.006). In patients with proteinuria of <0.5 g/d, sodium excretion was not associated with the primary outcome. However, in patients with proteinuria of ≥0.5 g/d, a 1.0 g/d increase in sodium excretion was associated with a 29% higher risk of adverse kidney outcomes. Moreover, in patients with proteinuria of ≥0.5 g/d, the hazard ratios (HRs) (95% confidence intervals[CIs]) for sodium excretion of <3.4 and ≥3.4 g/d were 2.32 (1.50-3.58) and 5.71 (3.58-9.11), respectively, compared with HRs for patients with proteinuria of <0.5 g/d and sodium excretion of <3.4 g/d. In sensitivity analysis with 2 averaged values of sodium and protein excretion at baseline and third year, the results were similar. Conclusion: Higher urinary sodium excretion was more strongly associated with an increased risk of adverse kidney outcomes in patients with higher proteinuria levels.

High Sodium Intake, as Assessed by Urinary Sodium Excretion, Is Associated with Nonalcoholic Fatty Liver Disease or Sarcopenia.

Background/Aims: We explored whether high sodium intake, assessed by urinary excretion, determines the risk of sarcopenia and nonalcoholic fatty liver disease (NAFLD). Methods: We analyzed 10,036 adult participants with normal kidney function from the Korea National Health and Nutrition Examination Survey (2008-2011). NAFLD was identified using the fatty liver index, and the muscle mass was evaluated using dual X-ray absorptiometry. The dietary sodium intake was estimated using Tanaka's equation. Results: The mean 24-hour urinary sodium excretion was 144.2±36.1 mmol/day (corresponding to 3.3 g/day Na) in the total population. The 24-hour urinary sodium excretion showed moderate accuracy in predicting NAFLD (area under the receiver operating characteristic, 0.702; 95% confidence interval [CI], 0.692 to 0.712). A cutoff value of 99.96 mmol/day (corresponding to 2.30 g/day Na) for urinary sodium excretion in predicting NAFLD showed 76.1% sensitivity and 56.1% specificity. The results of multiple adjusted models indicated that the participants with the highest urinary sodium excretion had a significantly higher risk of NAFLD (odds ratio, 1.46; 95% CI, 1.27 to 1.66; p<0.001) and sarcopenia (odds ratio, 1.49; 95% CI, 1.28 to 1.73; p<0.001) than those with the lowest urinary sodium excretion. The association between a higher 24-hour urinary sodium excretion and NAFLD was independent of sarcopenia. Conclusions: Participants with a high sodium intake, as assessed by sodium excretion, had a substantial risk of NAFLD and sarcopenia.

24-Hour Urinary Sodium Excretion Association with Cardiovascular Events: A Systematic Review and Dose-Response Meta-Analysis.

Objective: The relationship between sodium intake and cardiovascular (CV) events remains unconfirmed. Therefore, we carried out a systematic review and dose-response meta-analysis for evaluating the potential impact of 24-hour sodium excretion on CV risk. Besides, 24-hour sodium excretion was used to replace daily sodium diet intake. Methods: We searched ISI Web of Science, Embase, PubMed, and the Cochrane Library. Our study included cohort studies reporting hazard ratio ( HR). The random-effects model was used for summarizing the total relative risks ( RRs) between the included studies. In addition, the generalized least-squares regression was employed to fit the study model. Results: A total of 9 studies involving 645,006 participants were included in this study. A significant non-linear relationship was observed between sodium excretion and CV events ( P non-linearity < 0.001). In studies collecting 24-h urine samples, the sodium excretion and CV events risk were associated linearly ( RR: 1.04; 95% CI: 1.01, 1.07). Conclusion: In a linear dose-response manner, every 1 g increase in sodium intake was associated with an increased risk of CV events up to 4%. Further studies are required to validate our conclusions further.

Salt-Related Knowledge, Attitudes, and Behaviors and Their Relationship with 24-Hour Urinary Sodium Excretion in Chinese Adults.

Salt intake in China is very high, which increases the risk of hypertension and cardiovascular disease. This study aimed to assess the levels of salt-related knowledge, attitudes, and behaviors (KABs) and the factors that influence them and to explore the relationship between the scores of salt-related KAB and 24-h urinary sodium excretion. In 2018, we collected data from 5453 individuals aged 18-75 years from six provinces in China. A face-to-face survey was carried out, focusing on the KAB related to salt reduction. All participants were asked to collect one 24-h urine sample. Of the 5453 participants, 5352 completed urine collection. The mean score for overall KAB was 31.27 (SD = 9.18), which was composed of three elements: knowledge 4.80 (SD = 5.14), attitude 9.33 (SD = 3.93), and behavior 17.14 (SD = 4.43). The average 24-h urinary sodium excretion was 187.70 (SD = 77.48) mmol, which was equivalent to a urinary sodium excretion of 4.32 (SD = 1.78) g/d. We found that salt-related knowledge, attitude, behavior, and overall KAB scores were all inversely associated with 24-h urinary sodium excretion. For every one-point increase in the KAB score, the 24-h urinary sodium excretion decreased by 0.851 mmol (95% CI: -1.095, -0.602). We also found that location (rural/urban), sex, age, and education are associated with salt-related KAB scores. These results suggest that large-scale health education is needed to reduce salt intake in the Chinese population. In particular, efforts should be focused on reaching those who live in rural areas with low educational levels and older people.

Association between urinary sodium excretion and hard outcomes in non-dialysis chronic kidney disease patients.

BACKGROUND: Restriction of sodium intake is routinely recommended for patients with chronic kidney disease (CKD). Whether or not sodium intake is associated with the progression of CKD and mortality remains uncertain. We evaluated the association between urinary sodium excretion (as a surrogate for sodium intake) with the occurrence of renal failure and mortality in patients with non-dialytic CKD. METHODS: We conducted a retrospective study of patients followed at a CKD clinic care hospital from October 2006 to March 2017. Adult patients with non-dialytic CKD were included. Using a time-to-event analysis, we examined the association of urinary sodium excretion as a categorical variable (categorized as quintiles: 1st quintile: 0.54-2.51 g; 2nd quintile: 2.52-3.11 g, 3rd quintile: 3.12-3.97 g, 4th quintile: 3.98-5.24 g and 5th quintile: 5.26-13.80 g) and the outcomes of interest. The primary outcome was defined as progression to end-stage renal disease requiring any type of renal replacement therapy. The secondary outcome was mortality. RESULTS: Two hundred five patients were included in the study (mean follow up of 2.6 years) with a mean eGFR of 26 (19-41) ml/min/1.73m2. 37 patients (18%) required renal replacement therapy and 52 (25,3%) died. There was association between urinary sodium excretion and need for renal replacement therapy (adjusted HR 0.245; 95%CI 0.660-0.912). There was no association between urinary sodium excretion and mortality in adjusted models. CONCLUSION: Moderate sodium intake was associated with a lower risk of renal failure.

Antihypertensive Effect of Long-Term Monotherapy with Esaxerenone in Patients with Essential Hypertension: Relationship Between Baseline Urinary Sodium Excretion and Its Antihypertensive Effect.

INTRODUCTION: The blood pressure (BP) control mechanism for mineralocorticoid receptor blockers is unclear, and analysis of their use as a single agent in the clinical setting is required to resolve this uncertainty. There is a paucity of data on esaxerenone monotherapy assessing its long-term antihypertensive effect and urinary biomarkers. METHODS: This post hoc exploratory substudy of a long-term phase 3 study evaluated the effect of esaxerenone monotherapy (2.5 or 5 mg/day) in treatment-naïve patients who continued the therapy during the 52-week study period (n = 25). In addition to blood biomarkers, urinary biomarkers were also assessed in 24-h urine collection samples. RESULTS: Esaxerenone monotherapy was associated with consistent reductions in systolic/diastolic BP in the substudy population (- 23.5/- 13.1 mmHg at week 52, p < 0.001 vs baseline). Plasma aldosterone concentrations and plasma renin activity significantly increased during esaxerenone monotherapy at all time points. On the basis of the observations that both urine volume and urinary sodium excretion also decreased up to the end of the study, and were significantly lower at 12 weeks, patients were further categorized into higher/lower urinary sodium excretion subgroups according to whether their baseline values were above or below the median. In the group with higher baseline urinary sodium excretion, esaxerenone exhibited a significantly greater decrease in systolic/diastolic BP compared to the lower baseline group. CONCLUSION: Esaxerenone exhibited sustained and stable antihypertensive activity even when administered as a single agent for 52 weeks in patients with essential hypertension. The additional urinary biomarker analysis suggests that the BP-lowering effects of esaxerenone may be partly exerted via mechanisms related to salt and water retention, and that the effect is particularly pronounced in patients with hypertension and higher baseline urinary sodium excretion, which may reflect a state of excessive salt intake. TRIAL REGISTRATION: NCT02722265.

Twenty-Four-Hour Urinary Sodium Excretion Predicts Therapeutic Effectiveness of Oral Rehydration Saline in Pediatric Vasovagal Syncope.

The study was designed to explore whether 24-hour urinary sodium excretion could predict the therapeutic effectiveness of oral rehydration saline in pediatric cases of vasovagal syncope. Eighty children suffering from vasovagal syncope with oral rehydration saline treatment in Department of Pediatrics, Peking University First Hospital, China, were recruited into the study. They were followed up for 3 (2, 3) months after treatment. Pre-treatment demographic, clinical, head-up tilt test-based hemodynamic and laboratory variables were compared between responders and non-responders. After univariate analysis, variables with p value < 0.05 in the comparison between responders and non-responders were further analyzed by binary logistic regression analysis. Receiver operating characteristic (ROC) curve was conducted to assess the value in predicting effectiveness of oral rehydration saline treatment. The results showed that 33 cases were responders, and 47 were non-responders. Blood sodium (138 ± 2 mmol/L vs. 139 ± 2 mmol/L, p < 0.05) and pre-treatment 24-hour urinary sodium excretion (74 ± 29 mmol/24 h vs. 109 (93, 141) mmol/24 h, p < 0.001) were lower in responders than in non-responders. The baseline 24-hour urinary sodium excretion was positively correlated to the duration from tilting to the positive response appearance in head-up tilt test (r = 0.289, p < 0.01). The cut-off value of baseline 24-hour urinary sodium excretion of the therapeutic effectiveness of oral rehydration saline on vasovagal syncope cases was 83 mmol/24 h, yielding a sensitivity of 87% and a specificity of 73% with AUC of 0.842 (p < 0.001). In conclusion, 24-hour urinary sodium excretion could be a useful biomarker to predict the therapeutic response to oral rehydration saline in pediatric cases of vasovagal syncope.

Urinary sodium excretion and the risk of CVD: a community-based cohort study in Taiwan.

Urinary Na excretion is a potential risk factor for CVD. However, the underlying biological mechanisms and effects of salt sensitivity are unclear. The purpose of this study was to characterise the relative contribution of biological factors to the Na-CVD association. A total of 2112 participants were enrolled in this study. Structured questionnaires and blood and urine samples were obtained. Twenty-four-hour Na excretion was estimated using a single overnight urine sample. Hypertension, the metabolic syndrome and overweight status were considered to indicate salt sensitivity. Cox proportional hazard models were used to investigate the effects of salt sensitivity on urinary Na excretion and CVD risk. The traditional mediation approach was used to calculate the proportion of mediation. The mean age (sd) of the 2112 participants was 54·5 (sd 12·2) years, and they were followed up for a mean of 14·1 (sd 8·1) years. Compared with those in the lowest quartile, the highest baseline urinary Na excretion (>4·2 g/24 h) was associated with a 43 % higher CVD risk (hazard ratio, 1·43; 95 % CI 1·02, 1·99). Participants with high urinary Na excretion, hypertension or the metabolic syndrome had a significantly high risk of CVD. The carotid intima-media thickness had the largest mediating effect (accounting for 35 % of the Na-CVD association), followed by systolic blood pressure (BP) (33 %), left ventricular mass (28 %) and diastolic BP (14 %). Higher urinary Na excretion increased the risk of CVD, which was explained largely by carotid media-thickness and systolic BP.

A multiple 24-hour urine collection study indicates that kidney function decline is related to urinary sodium and potassium excretion in patients with chronic kidney disease.

Multiple 24-hour urine collections are necessary to adequately assess sodium and potassium intake. Here, we assessed kidney function decline for four years after baseline in relation to seven-time averaged 24-hour urinary sodium and potassium excretion (UNaV, UKV), their UNaV/UKV ratio, and their categorical combination in outpatients with chronic kidney disease (CKD). This retrospective cohort study was based on 240 outpatients with baseline CKD stages 3-5, baseline age 20 years or more (median age 72.0 years), and a median follow-up (with interquartile range) of 2.9 (1.4-4.0) years. Outcome was the percentage change in annual slope of estimated glomerular filtration rate (delta eGFR per year). In linear mixed models, percentage changes in delta eGFR per year were -3.26% (95% confidence interval -5.85 to -0.60), +5.20% (2.34 to 8.14), and -5.20% (-7.64 to -2.69), respectively, per one standard deviation increase in the seven-time averaged UNaV and UKV, and their UNaV/UKV ratio. Additionally, percentage changes per year in delta eGFR per year were -16.27% (-23.57 to -8.27) in the middle-to-high UNaV and low UKV group, compared with the low UNaV and middle-to high UKV group. Thus, our study reinforces the observation of opposite associations between GFR decline and urinary excretion rates of sodium (positive) and potassium (negative), respectively. Whether changes in dietary sodium and potassium intake slow GFR decline still requires further study.

Association of Urinary Sodium Excretion and Diabetic Kidney Disease in Patients With Type 2 Diabetes Mellitus: A Cross-Sectional Study.

Background: Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease worldwide. Epidemiological evidence of the association between urinary sodium excretion and the presence of DKD in patients with type 2 diabetes mellitus (T2DM) has not yet been well established. Methods: We performed a cross-sectional study of 1545 patients with T2DM over aged 20 years old from January 2018 to December 2020. Urinary sodium excretion was measured by 24-hour urine samples in inpatients and morning fasting urine samples in outpatients. The associations between urinary sodium excretion and the risks of DKD were examined using stepwise regression analysis, logistic regression analysis and multivariable-adjusted restricted cubic splines (RCS). Results: Regression analysis showed that urinary sodium was independently associated with urinary albumin to creatinine ratio (UACR) level (P = 0.006) and the risks of DKD (P = 0.042). In multivariable-adjusted RCS analysis, urinary sodium excretion was significantly associated with UACR in all patients (P = 0.008), and exhibited a J-shaped relationship. Logistic regression analysis showed that increased urinary sodium excretion was significantly associated with increased risks of DKD [OR (95% CI); 1.56 (1.07-2.27); P = 0.020]. However, the relationships between urinary sodium excretion and the risks of DKD and albuminuria showed no significance, after further adjustment for HOMA-IR and ba-PWV (brachial-ankle pulse wave velocity) (Both P > 0.05). Conclusions: Higher urinary sodium excretion level was associated with increased risks of DKD among patients with T2DM, dependent of vascular sclerosis and insulin resistance.

Association of Urinary Sodium Excretion and Left Ventricular Hypertrophy in People With Type 2 Diabetes Mellitus: A Cross-Sectional Study.

Background: It has been well documented that left ventricular hypertrophy (LVH) is highly associated with the incidence of cardiovascular disease (CVD). Evidence indicated that high sodium intake was closely related with LVH in general population. However, information is not available regarding the association between urinary sodium excretion and LVH in patients with type 2 diabetes mellitus (T2DM). This study aimed to explore the association between urinary sodium excretion and LVH in patients with T2DM. Methods: This cross-sectional analysis included baseline data from 1,556 individuals with T2DM enrolled in the NanFang Prospective Diabetes Study (NFPDS). Urinary sodium excretion levels were measured from 24-hour urine samples of inpatients and morning fasting urine samples of outpatients. Left ventricular dimensions were assessed by echocardiography. The associations between urinary sodium excretion and the risks of cardiovascular events, LVH and left ventricular mass index (LVMI) were examined using linear regression analysis, logistic regression and restricted cubic splines (RCS). Results: Urinary sodium excretion levels were positively associated with cardiometabolic risk factors, including systolic blood pressure, body mass index, waist circumference and LVMI (All P<0.001). Odds ratios of the highest quartile of urinary sodium excretion compared with the lowest quartile were 1.80 (95% CI, 1.28-2.54; P=0.001) for LVH and 1.77 (95% CI, 1.06-2.94; P=0.028) for CVD, after adjusted for demographics, lifestyle risk factors and cardiovascular risk factors. Multivariable-adjusted RCS analysis of the association between urinary sodium excretion and LVMI showed a significant association (P=0.001) and lacked evidence of a nonlinear association (P=0.406). Conclusion: This study indicated that high urinary sodium excretion was independently associated with increased risk of LVH and CVD in patients with T2DM, suggesting that control of sodium intake may be valuable for the prevention of diabetic cardiovascular complications.