Urinary Potassium Excretion Research Articles

Long-Term Effects of a Comprehensive Intervention Strategy for Salt Reduction in China: Scale-Up of a Cluster Randomized Controlled Trial

Background: Salt intake in China was high and a series of salt reduction measures were accordingly carried out recently. Our study aimed to assess the long-term effect of a scale-up community randomized controlled trial (RCT); Methods: Individuals between the ages of 18 and 75, from six provinces in China, were recruited and randomized into control (n = 1347) and intervention (n = 1346) groups. A one-year salt reduction intervention was first implemented in the intervention group, followed by a two-year scale-up intervention in both groups. The 24 h urine sample, anthropometric measurement, and knowledge, attitude, and practice (KAP) of salt reduction, as well as lifestyle information, were collected at baseline, after one-year RCT (mid-term evaluation, n = 2456), and two-year scale-up intervention (terminal evaluation, n = 2267); Results: Both control (351.82 mg/24 h, p < 0.001) and intervention (192.84 mg/24 h, p = 0.006) groups showed a decrease in 24 h urinary sodium excretion from baseline to terminal evaluation. Except for an increase in 24 h urinary potassium excretion (85.03 mg/24 h, p = 0.004) and a decrease in systolic blood pressure (SBP) (2.95 mm Hg, p < 0.001) in the intervention group at the mid-term assessment, no statistically significant differences in other indicators were found between two groups. The KAP of salt reduction in two groups was gradually improved; Conclusions: After one-year RCT two-year scale-up, all participants showed a decreasing trend in 24 h urinary sodium excretion and an increase in salt reduction KAP. The community salt reduction intervention package has the potential for broader application across other regions in China.

Knowledge, Attitudes, and Behaviors Toward Salt Consumption and Its Association With 24-Hour Urinary Sodium and Potassium Excretion in Adults Living in Mexico City: Cross-Sectional Study.

The World Health Organization recommends a daily sodium intake of less than 2000 mg for adults; however, the Mexican population, like many others globally, consumes more sodium than this recommended amount. Excessive sodium intake is often accompanied by inadequate potassium intake. The association between knowledge, attitudes, and behaviors (KAB) and actual sodium intake has yielded mixed results across various populations. In Mexico, however, salt/sodium-related KAB and its relationship with sodium and potassium intake have not been evaluated. This study primarily aims to describe salt/sodium-related KAB in a Mexican population and, secondarily, to explore the association between KAB and 24-hour urinary sodium and potassium excretion. We conducted a cross-sectional study in an adult population from Mexico City and the surrounding metropolitan area. Self-reported KAB related to salt/sodium intake was assessed using a survey developed by the Pan American Health Organization. Anthropometric measurements were taken, and 24-hour urinary sodium and potassium excretion levels were determined. Descriptive statistics were stratified by sex and presented as means (SD) or median (25th-75th percentiles) for continuous variables, and as absolute and relative frequencies for categorical variables. The associations between KAB and sodium and potassium excretion were assessed using analysis of covariance, adjusting for age, sex, BMI, and daily energy intake as covariates, with the Šidák correction applied for multiple comparisons. Overall, 232 participants were recruited (women, n=184, 79.3%). The mean urinary sodium and potassium excretion were estimated to be 2582.5 and 1493.5 mg/day, respectively. A higher proportion of men did not know the amount of sodium they consumed compared with women (12/48, 25%, vs 15/184, 8.2%, P=.01). More women reported knowing that there is a recommended amount for daily sodium intake than men (46/184, 25%, vs 10/48, 20.8%, P=.02). Additionally, more than half of men (30/48, 62.5%) reported never or rarely reading food labels, compared with women (96/184, 52.1%, P=.04). Better salt/sodium-related KAB was associated with higher adjusted mean sodium and potassium excretion. For example, mean sodium excretion was 3011.5 (95% CI 2640.1-3382.9) mg/day among participants who reported knowing the difference between salt and sodium, compared with 2592.8 (95% CI 2417.2-2768.3) mg/day in those who reported not knowing this difference (P=.049). Similarly, potassium excretion was 1864.9 (95% CI 1669.6-2060.3) mg/day for those who knew the difference, compared with 1512.5 (95% CI 1420.1-1604.8) mg/day for those who did not (P=.002). Additionally, higher urinary sodium excretion was observed among participants who reported consuming too much sodium (3216.0 mg/day, 95% CI 2867.1-3565.0 mg/day) compared with those who claimed to eat just the right amount (2584.3 mg/day, 95% CI 2384.9-2783.7 mg/day, P=.01). Salt/sodium-related KAB was poor in this study sample. Moreover, KAB had a greater impact on potassium excretion than on sodium excretion, highlighting the need for more strategies to improve KAB related to salt/sodium intake. Additionally, it is important to consider other strategies aimed at modifying the sodium content of foods.

Independent and joint associations of urinary potassium excretion with cardiovascular death: a national population-based cohort study

Abstract Background Elevated potassium excretion is associated with lower blood pressure, as well as reduced risks of cardiovascular disease (CVD) death. However, the impact of varied sodium levels on this association remains a topic of debate, and the mediators of this association besides blood pressure remain uncertain. Purpose To examine the joint association of potassium and sodium with CVD mortality risk, and to identify potential mediating factors of this association. Methods Based on the ChinaHEART (China Health Evaluation And risk Reduction through nationwide Teamwork) project, participants aged 35-75 from 239 sites across all 31 provinces in the mainland of China were recruited from November 2014 to December 2022. We collected spot urine samples from participants and estimated 24-hour sodium and potassium excretion using the Kawasaki formula. Death records were captured through data linkage with the National Mortality Surveillance System and Vital Registration. Multiple regressions were used to analyze the association between potassium excretion and CVD death, as well as to examine the addictive interaction of potassium and sodium. Results This study included 270,991 participants with a mean age of 55.8±9.8 years, and 60.5% of them were female. The mean potassium excretion was 54.36±12.58 mmol/d , which was higher in males and people living in the north. Findings revealed a positive correlation between low urinary potassium levels and CVD death , and the lowest adjusted hazard rate for CVD mortality was 0.65 (95% CI: 0.58-0.73) in the group with the highest potassium excretion (i.e. ≥64.27 mmol/d) compared with the reference group (<43.79 mmol/d), after adjusting for sociodemographic characteristics, medical histories, and lifestyles. Age modified the association between potassium excretion and risk of CVD death (P for interaction=0.031). In addition to systolic blood pressure (16.6%), heart rate (2.2%) also served as the significant mediator between urinary potassium excretion and CVD death. The relative excess risk of interaction (RERI) of lower potassium excretion and lower sodium was significantly positive (RERI=0.22, 95% CI: 0.02-0.42), which implied the synergy effect. Conclusion Potassium intake in the Chinese population is evidently lower than the guideline recommendations, and increasing potassium intake, especially in the population aged <65 years, may reduce the risk and burden of cardiovascular and other diseases. Moreover, when sodium intake is insufficient, supplementation with both sodium and potassium salt can achieve greater health benefits.Graphic abstract

Salt-related knowledge, attitudes and practices and their relationship with 24-h urinary sodium and potassium excretions among a group of healthy residents in the UAE: a cross-sectional study.

This study aimed to measure urinary sodium and potassium as a measure of sodium and potassium intake concerning the knowledge, attitude and practice towards sodium intake among a group of healthy residents in the UAE. A cross-sectional study on a sample of healthy adults in the UAE. In addition to the knowledge, attitude and practice questionnaire, sodium and potassium excretions and food records were taken. The UAE. A sample of 190 healthy individuals aged between 20 and 60 years. The mean (± sd) age of the sample was 38·6 (± 12·5) years, and 50·5 % were females. The mean urinary sodium and potassium intake were 2816·2 ± 675·7 mg/d and 2533·3 ± 615 mg/d, respectively. The means were significantly different compared with the WHO recommendation of sodium and potassium (P < 0·001). About 65 % of the participants exceeded the WHO recommendations for salt intake, and participants' knowledge classification for health-related issues was fair, while food-related knowledge was poor (P = 0·001). A two-stage stepwise multiple regression analysis revealed that knowledge, attitude and practice scores were negatively associated with urinary sodium excretion (r = -0·174; P = 0·017) and those older participants and females had lower urinary sodium excretion (P < 0·001). These findings may suggest an increase in the risk of hypertension in the UAE population. Moreover, these findings emphasise the need to establish education and public awareness programmes focusing on identifying the sodium contents of foods and establishing national regulations regarding food reformulation, particularly for staple foods such as bread.

Association of Urinary Sodium, Potassium, and the Sodium-to-Potassium Ratio with Impaired Kidney Function Assessed with 24-H Urine Analysis.

Background: Albuminuria and albumin excretion rate (AER) are important risk factors for chronic kidney disease (CKD) development. Despite the extensive evidence of the influence of sodium and potassium on cardiovascular health, the existing evidence regarding their impact on albuminuria and kidney disease is limited and inconsistent. Our study aimed to assess the correlation between urinary sodium and potassium excretion, and the sodium-to-potassium ratio (Na/K ratio) with impaired kidney function, particularly the AER and albuminuria. Materials and Methods: Data were collected from the Lithuanian NATRIJOD study. A total of 826 single 24-h urine samples from individuals aged 18 to 69 were collected and analyzed for their sodium and potassium levels, Na/K ratio, and AER. Albuminuria was defined as an AER exceeding 30 mg/24 h. Results: The participant mean age was 47.2 ± 12.1 years; 48.5% of the participants were male. The prevalence of albuminuria was 3%. Correlation analysis revealed a positive correlation between AER and urinary sodium excretion (rs = 0.21; p < 0.001) and urinary potassium excretion (rs = 0.28; p < 0.001). In univariate linear regression analysis, sodium and potassium excretion and the Na/K ratio were significant AER predictors with β coefficients of 0.028 (95% CI: 0.015; 0.041; p < 0.001), 0.040 (95% CI: 0.003; 0.077; p = 0.035), and 1.234 (95% CI: 0.210; 2.259; p = 0.018), respectively. In the multivariable model, only urinary sodium excretion remained significant, with a β coefficient of 0.028 (95% CI: 0.016; 0.041). Potential albuminuria predictive factors identified via univariate logistic regression included urinary sodium excretion (OR 1.00; 95% CI: 1:00; 1.01) and the Na/K ratio (OR 1.53; 95% CI: 1.11; 2.05). However, these factors became statistically insignificant in the multivariate model. Conclusions: Urinary sodium and potassium excretion and the Na/K ratio are significantly associated with kidney damage, considering the assessed 24-h albumin excretion rate and presence of albuminuria content.

Antiurolithic activity of Zaleya pentandra (L.) C Jeffrey in ethylene glycol-induced calcium oxalate crystal rat model; A scientific validation of traditional use for kidney stone prevention

Ethnopharmacological relevanceTraditional herbal remedies have been used for treating nephrolithiasis, but the relevant scientific evidence is limited. Zaleya pentandra (L.) C. Jeffrey is traditionally used for the prevention of kidney stones in various cultures. However, its efficacy has not been scientifically studied. Aim of the studyThis study aimed to investigate the antiurolithic activity of Zaleya pentandra, and validate its traditional used for preventing kidney stones. Materials and methodsThe crude ethanolic extract of Z. pentandra (Zp.Crd) was evaluated through in vitro and in vivo studies. In vitro experiments assessed its impact on crystal count and morphology in metastable calcium oxalate solutions. In vivo studies involved diuretic and ethylene glycol-induced calcium oxalate crystal formation in male Wistar rats. ResultsZp.Crd transforms calcium oxalate crystals from harmful calcium oxalate monohydrate (COM) to calcium oxalate dihydrate (COD). In vivo, Zp.Crd exhibited dose-dependent (30–300 mg/kg) diuretic activity in rats by significantly increasing urinary sodium (Na+) and potassium (K+) excretion, similar to the standard diuretic hydrochlorothiazide (HCT). In the urolithiasis model, Zp.Crd exhibited dose-dependent antiurolithic effects by reducing kidney crystals and significantly altering lithogenic factors induced by ethylene glycol, including crystalluria, oxaluria, calcium, creatinine, and urea, in the urine and serum of treated rats. Zp.Crd also exhibited antioxidant effects, effectively combating oxidative lithogenic stress in rats. ConclusionZp.Crd has been shown to demonstrate antiurolithic activity against CaOx stones through CaOx crystal inhibition, diuretic activity, antioxidant properties, hypocalciuric effects, and hypercitrauric actions. The findings underscore Zp.Crd's potential as a viable alternative or supplemental therapy to current urolithiasis treatments, paving the door for further clinical trials and its inclusion into modern medical practices.

Community-level dietary intake of sodium, potassium, and sodium-to-potassium ratio as a global public health problem: a systematic review and meta-analysis

Background: Widespread adoption of a westernized diet represents a major lifestyle change characterized by substantially higher sodium consumption and lower potassium intake, which is related to cardiovascular morbidity. Methods: We performed a systematic review and meta-analysis over published studies in accordance with quantifying the dietary intake of sodium and potassium of the universal population across the world. The PubMed, EMBASE, Cochrane Library, and Google Scholar databases were used to find research that pronounced 24-hour urinary sodium or potassium excretion (reference period: 2014–2021). The effect size was estimated using the fixed-effect model; sub-group analysis become accomplished to determine urinary sodium and potassium excretion disaggregated by geographical location. Publication bias became evaluated the usage of graphical funnel plot. Data analysis was performed using STATA 16. Results: Forty-three studies (n= 62,940) qualified the selection criteria. The mean urinary excretion of sodium and potassium was 156.73 mmol/24h [95% confidence interval (CI), 148.98–164.47] and 48.89 mmol/24 h (95% CI, 43.61–54.17), respectively; the mean urinary sodium/potassium ratio was 3.68 (95% CI, 2.96–4.40). Conclusions: This updated systematic review highlights excessively high dietary intake of sodium and low intake of potassium at the community level in most parts of the world. The urinary Na/K ratio exceeded the level recommended by the WHO guidelines.

The Impact of 24 h Urinary Potassium Excretion on High-Density Lipoprotein Cholesterol and Chronic Disease Risk in Chinese Adults: A Health Promotion Study.

Research into the pivotal role of potassium in chronic diseases and their comorbidities remains scarce. Our aim is to elucidate the relationship between potassium and chronic diseases, including comorbid conditions, and to provide evidence-based recommendations for potassium intake in patients. This study is anchored in a representative, population-based survey conducted in Zhejiang Province, China, in 2017, encompassing participants aged 18 to 69 years. Data collection included questionnaire responses, physical measurements, and biological samples, obtained through a multistage cluster random sampling method. A subset of 1496 participants provided complete 24 h urine samples. The median age of the participants was 48.0 years (interquartile range [IQR] 24.0), with 51.1% being female, and hypertension was identified in more than one third (35.6%) of the participants. The prevalence of diabetes was approximately 9.0%, dyslipidemia was found in 34.2%, and microalbuminuria in 8.8%. The 24 h urinary excretion levels were 3613.3 mg/24 h (IQR 2161.7) for sodium and 1366.0 mg/24 h (IQR 824.9) for potassium, respectively. Potassium excretion exhibited an inverse relationship with blood pressure. Furthermore, a positive correlation was observed between potassium excretion and high-density lipoprotein cholesterol (HDL-C) levels, with an elevation of 0.03 mmol/L (95% confidence interval [CI] 0.00 to 0.05). In binary logistic regression analysis, individuals in the fourth quartile of potassium excretion (Q4) exhibited an odds ratio (OR) of 0.56 (95% CI 0.36-0.87) for hypertension compared to those in the first quartile (Q1). Urinary potassium excretion was inversely associated with low HDL-C levels, with Q4 individuals having 0.62 times the odds of having low HDL-C levels (OR, 0.62; 95% CI 0.39-1.00) compared to Q1. Potassium excretion demonstrated a direct negative correlation with certain comorbidities. This study underscores the pivotal role of potassium in the management of chronic diseases and associated comorbidities, thereby highlighting the significance of potassium in both public health initiatives and clinical practice.

Twenty-four hour urinary sodium and potassium excretion in adult population of Slovenia: results of the Manjsoli.si/2022 study.

The objective of study was to assess 24-h urinary Na and K excretion and estimate the average salt and K intakes in a nationally representative sample of the adult population of Slovenia. A nationally representative cross-sectional study was conducted in four stages between September and November 2022: study questionnaire, physical measurements, 24-h urine collection and laboratory analysis. Slovenia. We invited 2000 adult, non-institutionalised inhabitants of Slovenia, aged between 25 and 64 years. A stratified two-staged sample was selected from this population by the Statistical Office of Slovenia, using sampling from the Central Population Register. According to the WHO methodology, additional eligibility criteria were screened before participating. A total of 518 individuals participated in all four stages of the study, resulting in a response rate of 30 %. The mean 24-h urinary Na excretion was 168 mmol/d (95 % CI 156, 180), which corresponds to a mean estimated intake of 10·3 g salt/d (95 % CI 9·6, 11·1). Mean 24-h urinary K excretion was 65·4 mmol/d (95 % CI 63·2, 67·5), and the estimated mean K intake was 2·93 g/d (95 % CI 2·84, 3·03). There were statistically significant differences in mean intakes between males and females. The mean sodium-to-potassium ratio was 2·7 (95 % CI 2·5, 2·8). The study results highlighted that the salt intake in the adult population of Slovenia remains much higher than recommended by the WHO, and K intakes are insufficient, as most participants did not meet the recommendations.

GLP-1RA vs DPP-4i Use and Rates of Hyperkalemia and RAS Blockade Discontinuation in Type 2 Diabetes

Hyperkalemia is a common complication in people with type 2 diabetes (T2D) that may limit the use of guideline-recommended renin-angiotensin system inhibitors (RASis). Emerging evidence suggests that glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase urinary potassium excretion, which may translate into reduced hyperkalemia risk. To compare rates of hyperkalemia and RASi persistence among new users of GLP-1RAs vs dipeptidyl peptidase-4 inhibitors (DPP-4is). This cohort study included all adults with T2D in the region of Stockholm, Sweden, who initiated GLP-1RA or DPP-4i treatment between January 1, 2008, and December 31, 2021. Analyses were conducted between October 1, 2023, and April 29, 2024. GLP-1RAs or DPP-4is. The primary study outcome was time to any hyperkalemia (potassium level >5.0 mEq/L) and moderate to severe (potassium level >5.5 mEq/L) hyperkalemia. Time to discontinuation of RASi use among individuals using RASis at baseline was assessed. Inverse probability of treatment weights served to balance more than 70 identified confounders. Marginal structure models were used to estimate per-protocol hazard ratios (HRs). A total of 33 280 individuals (13 633 using GLP-1RAs and 19 647 using DPP-4is; mean [SD] age, 63.7 [12.6] years; 19 853 [59.7%] male) were included. The median (IQR) time receiving treatment was 3.9 (1.0-10.9) months. Compared with DPP-4i use, GLP-1RA use was associated with a lower rate of any hyperkalemia (HR, 0.61; 95% CI, 0.50-0.76) and moderate to severe (HR, 0.52; 95% CI, 0.28-0.84) hyperkalemia. Of 21 751 participants who were using RASis, 1381 discontinued this therapy. The use of GLP-1RAs vs DPP-4is was associated with a lower rate of RASi discontinuation (HR, 0.89; 95% CI, 0.82-0.97). Results were consistent in intention-to-treat analyses and across strata of age, sex, cardiovascular comorbidity, and baseline kidney function. In this study of patients with T2D managed in routine clinical care, the use of GLP-1RAs was associated with lower rates of hyperkalemia and sustained RASi use compared with DPP-4i use. These findings suggest that GLP-1RA treatment may enable wider use of guideline-recommended medications and contribute to clinical outcomes in this population.

Pathological and functional significance of aging mouse kidneys: clinical implications to reduce the risk of hyper- or hypokalemia in the elderly.

Elderly patients are prone to develop hyper- or hypokalemia, since they are susceptible to drugs or diets that affect the urinary or fecal potassium (K+) excretion. In aging mouse kidneys, in addition to glomerulosclerosis, proximal tubular atrophy, and atherosclerosis in renal arterioles, there was diffuse tubulointerstitial fibrosis with a number of inflammatory leukocytes infiltrating into the cortical interstitium. Since these pathological features greatly influence renal K+ handling, slowing the progression of kidney aging would fundamentally reduce the risk of developing hyper- or hypokalemia. Immunohistochemistry demonstrated the overexpression of K+ channels (Kv1.3) in leukocytes within the cortical interstitium, which was strongly associated with "chronic inflammation" in aging kidneys and the subsequent progression of renal fibrosis. In our basic studies, antihypertensive drugs (benidipine, nifedipine, verapamil, diltiazem) and anticholesterol drugs (lovastatin, simvastatin, pravastatin) strongly suppressed the leukocyte Kv1.3 channels and thus exerted anti-inflammatory effects. Given such pharmacological properties of these drugs, they may also be useful in slowing the progression of tubulointerstitial fibrosis in aging kidneys and reducing the risk of hyper- or hypokalemia in elderly patients.

Glucocorticoid-induced acute diuresis in rats in relation to the reduced renal expression of sodium-dependent cotransporter genes

Although several studies have shown that glucocorticoids exert diuretic effects in animals and humans, the underlying mechanism responsible for the acute diuretic effect remains obscure. Here we examined the mechanism in terms of gene-expression. We observed that glucocorticoids, including dexamethasone (Dex) and prednisolone (PSL), acutely induced diuresis in rats in a dose-dependent manner. Free water clearance values were negative after Dex or PSL treatment, similar to those observed after treatment with osmotic diuretics (furosemide and acetazolamide). Dex significantly increased the urinary excretion of sodium, potassium, chloride, glucose, and inorganic phosphorus. Renal microarray analysis revealed that Dex significantly altered the renal expression of genes related to transmembrane transport activity. The mRNA levels of sodium/phosphate (NaPi-2a/Slc34a1, NaPi-2b/Slc34a2, and NaPi-2c/Slc34a3) and sodium/glucose cotransporters (Sglt2/Slc5a2) were significantly reduced in the Dex-treated kidney, being negatively correlated with the urinary excretion of their corresponding solutes. Dex did not affect renal expression of the natriuretic peptide receptor 1 (Npr1) gene, or the expression, localization, and phosphorylation of aquaporin-2 (AQP2), a water channel protein. These findings suggest that the acute diuretic effects of glucocorticoids might be mediated by reduced expression of sodium-dependent cotransporter genes.

Plant-based diet in hyperkalemic chronic kidney disease patients receiving sodium zirconium cyclosilicate: a feasibility clinical trial

BackgroundPlant-based diets (PBD) may induce hyperkalemia in chronic kidney disease (CKD) patients. ObjectivesWe explored the safety and feasibility of PBD in hyperkalemic CKD patients receiving the potassium binder sodium zirconium cyclosilicate (SZC). MethodsIn the current 6-wk trial, 26 hyperkalemic patients with CKD stage 4–5 not on dialysis received a low-protein low-potassium diet plus SZC for 3 wk and then a PBD with high potassium content delivered as a weekly food basket while continuing SZC for subsequent 3 wk. Plasma potassium was monitored weekly and SZC was titrated to achieve normokalemia. The 24-h urine excretion of potassium and sodium, 24-h food records, dietary quality, nutritional status, Bristol stool scale, Quality of life (QoL), and renal treatment satisfaction were assessed at baseline (week 0), week 3, and week 6. ResultsMean plasma potassium decreased from 5.5 to 4.4 mEq/L within 48–72 h after baseline, then rose to 4.7–5.0 mEq/L throughout the remaining study period following dose adjustments of SZC that matched the increased potassium intake of PBD from week 3 to week 6. Over the study period, 24-h urinary potassium excretion decreased from week 0 to week 3 and increased from week 3 to week 6. During the study, 58% of patients had fasting plasma potassium between 3.5 and 5.0 mEq/L and there was no episode of plasma potassium >6.5 mEq/L or <3.0 mEq/L during the study. P-carbon dioxide increased from baseline until week 6 (21 ± 2 to 23 ± 2 mEq/L; P = 0.002; mean ± SD), whereas remaining laboratory values remained unchanged. Fiber intake, dietary quality, the domain physical functioning from QoL, and 1 question of renal treatment satisfaction improved, whereas stool type and frequency did not change after starting PBD. ConclusionsPBD in hyperkalemia-prone CKD patients receiving SZC improved dietary quality and increased the intake of healthy foods, whereas plasma potassium concentration remained stable within normal values for most patients. Trial registration numberThis trial was registered at the https://clinicaltrials.gov/study/NCT04207203 as NCT04207203.

Associations between dietary potassium intake and urinary potassium excretion: a protocol for systematic review and meta-analysis

BackgroundWhile numerous studies have reported associations between low dietary potassium intake and adverse clinical outcomes, methods to estimate potassium intake, mainly self-reported dietary measures and urinary potassium excretion, entail certain limitations. Self-reported measures are subject to underreporting and overreporting. Urinary potassium excretion is affected by multiple factors including renal function. Revealing the degree of bias inherent in these measures would help accurately assess potassium intake and its association with disease risk. We aim to summarize evidence on the strength of the associations between potassium intake estimated from 24-h urinary potassium excretion and potassium intake estimated from self-reported dietary measures or objective quantification methods in populations with different kidney function levels and age groups. We also aim to identify factors that affect the association strength.MethodsWe will search for potentially eligible studies that examined associations between self-reported potassium intake, 24-h urinary potassium excretion, and objectively quantified potassium intake, using MEDLINE (PubMed), Embase, Web of Science, and Scopus. Studies on children, adolescents, adults, and the elderly are eligible. Studies of patients on dialysis will be excluded. Collective study results, including a meta-analysis, will be synthesized if an adequate number of studies examining similar dietary potassium intake estimation methods are found. Analyses will be performed separately according to age groups and renal function. For the meta-analysis, fixed-effects or random-effect models will be employed depending on the degree of study heterogeneity to combine across studies the correlation coefficient, ratio, or standardized mean difference for potassium intake, comparing dietary potassium intake based on self-reported or objectively quantified methods and intake based on 24-h urinary potassium excretion. The degree of heterogeneity among included studies will be examined by calculating I2 statistics. To investigate sources of study heterogeneity, random-effects meta-regression analyses will be performed.DiscussionRevealing the strength of the association between dietary and urinary measures in populations with different levels of kidney function and age groups will enhance researchers’ and clinicians’ ability to interpret studies that utilize these measures and help establish a more solid evidence base for the role of potassium intake in changing chronic disease risk. Identifying factors that modify the associations between these measures may aid in developing predictive models to estimate actual potassium intake.Systematic review registrationPROSPERO CRD42022357847.

#1642 Influence of potassium intake on the renoprotective response to sodium restriction and hydrochlorothiazide in patients with diabetic nephropathy

Abstract Background and Aims Both salt restriction and hydrochlorothiazide (HCT) potentiate the antihypertensive and antiproteinuric effects of renin-angiotensin-aldosterone-system inhibitors (RAASi) in chronic kidney disease (CKD). Potassium intake is another dietary component that influences blood pressure (BP) and albuminuria. The influence of potassium intake on the response to sodium restriction during RAASi treatment in diabetic nephropathy is unknown. Method We performed a post-hoc analysis of a randomised, double blind, placebo-controlled cross-over trial (n = 43) investigating the combined and separate effects of low sodium (LS; aim 50 mmol Na+/d) and HCT (50 mg/d) on BP and albuminuria during background ACE inhibition (ACEi; lisinopril 40 mg/d) in patients with diabetic nephropathy. Each treatment (normal sodium (NS), LS, NS+HCT, LS+HCT) period consisted of six weeks. Participants were categorised as above or below median 24-hour urinary potassium excretion (UKV) at baseline, stratified by sex. Effects on BP and albuminuria were defined as % reduction from baseline systolic BP (SBP) and urinary albumin-creatinine ratio (ACR). Changes over time within both UKV subgroups were compared to baseline using repeated measures ANOVA (SBP) or paired Wilcoxon rank sum analysis (log-transformed ACR). Post-hoc between-group comparison was performed using Bonferroni testing. Results 43 patients (6 female; mean age 64.9±1.4 yrs) had UKV data available and were included in analysis. 33 patients had complete ACR data. Mean estimated glomerular filtration rate (eGFR) was 65.2 (±3.9), mean SBP was 146.6±2.4 mmHg and median albuminuria 648.6 [251.2 - 1883.0] mg/24 h. Median UKV in the high and low potassium groups was 64 [IQR 49-71] and 94 [90 – 111] mmol/24 u, respectively (p&amp;lt;0.0001). Mean baseline sodium excretion was higher in the high potassium group (191 vs. 260 mmol/d; P = .002), but percentual reduction in sodium excretion at SR was comparable between the two groups. There were no significant differences in baseline SBP, ACR, age and estimated glomerular filtration rate between the groups. LS led to a significant reduction of ACR in the high potassium group (P = .011), whereas in the low potassium group the ACR reduction was not significant (P = .058; Fig. 1). Similarly, addition of HCT to background ACEi therapy without salt restriction reduced ACR compared to ACEi monotherapy in the high potassium group (P &amp;lt; .0001), not the low potassium group (P = .211). LS+HCT combined led to a reduction in ACR in both high (P &amp;lt; .0001) and low potassium (P = .034) groups. A post-hoc between-group analysis showed a significantly larger ACR reduction for the high potassium group (P = .01) upon HCT therapy, and a trend towards larger reduction for HCT+LS (P = .05). The effect of LS alone was similar between high and low potassium groups (P = .485). During LS, within-group analysis showed a significant reduction in SBP compared to baseline for the low potassium group (P = .003), but not for the high potassium group (P = .208). In all further conditions, SBP was significantly reduced from baseline in both groups. Post-hoc analysis showed no significant differences in SBP reduction between high and low potassium groups, although there was a trend towards larger SBP reduction in the low potassium group during LS (P = .07). Conclusion Higher baseline potassium excretion is associated with stronger albuminuria lowering effects of salt restriction and HCT in patients with diabetic nephropathy on background ACEi therapy. These effects were not driven by similar effects on BP.

#1429 Daily urinary potassium excretion is not a fixed percentage of daily potassium intake

Abstract Background and Aims High potassium intake is associated with a lower blood pressure and lower incidence of chronic kidney disease. Since a significant amount of potassium is lost via stool, the World Health Organization advices to multiply 24-hour renal potassium excretion by 1.3 for estimation of dietary intake. We analyzed whether this 1.3 factor for potassium intake varies in healthy volunteers and evaluated whether factors associated with tissue cation storage, namely sodium intake, aldosterone, cortisol and urine volume, affect the renal potassium excretion. Method We performed a post-hoc analysis of the long-term sodium balance studies Mars105 and Mars520. Ten healthy male participants consumed a fixed amount of salt (6, 9 and 12 grams/day for &amp;gt;29 days) and potassium (4 grams/day) for 105 (n = 4) and 205 days (n = 6). During the entire study period all urine was collected in 24-hour aliquots. We calculated the percentage of potassium intake that was excreted in the corresponding 24-hour urine collection during steady-state. We assessed whether this percentage was associated with sodium intake, potassium intake, urinary aldosterone, urinary cortisol and urine volume using a multivariable mixed-effects model. Results Overall, the median renal potassium excretion was 80% of potassium intake (IQR 65-97%; range 24-304%). This corresponds to a conversion factor of 1.25 (IQR 1.03-1.54). Within individual subjects we also observed a marked day-to-day variation in the percentage of renal potassium excretion: the average intraperson width of the IQR was 25%. A higher sodium intake was associated with an increased percentage of renal potassium excretion, whereas a higher potassium intake was associated with a decreased percentage of renal potassium excretion. A significant positive interaction between the effects of sodium and potassium intake was present (P &amp;lt; .001; Fig. A). Furthermore, urinary aldosterone (Fig. B), urinary cortisol (Fig. C) and urine volume (Fig. D) were positively associated with the percentage of renal potassium excretion. Conclusion The percentage of consumed potassium that is excreted via urine shows considerable intra- and inter-subject variability. During steady-state this percentage is independently affected by sodium intake, potassium intake, urinary aldosterone, urinary cortisol, and urine volume. Our results suggest that the WHO's fixed 1.3 conversion factor may lead to inaccurate estimations of potassium intake.

Calcineurin inhibitor-related hyperkalemia is caused by hyporeninemic hypoaldosteronism and fludrocortisone is an effective treatment: Report of a case series and review of the literature.

Calcineurin inhibitors (CNIs) are widely used in transplantation. Although CNI-related hyperkalemia is common (10%-60.6%), the underlying pathogenetic mechanism is not well-elucidated and may lead to dose adjustment or treatment withdrawal. The aim of this study is to describe CNI-related hyperkalemia due to hyporeninemic hypoaldosteronism in pediatric transplant recipients who were successfully treated with fludrocortisone. In a total of 55 hematopoietic stem cell (HSCT) and 35 kidney transplant recipients followed according to institutional immunosuppression protocols, recipients diagnosed with CNI-related hyperkalemia were reviewed. Recipients who were receiving intravenous fluid, potassium, or were diagnosed with hemolysis, acute graft rejection, or had an eGFR < 30 mL/min/1.73m2, were excluded. A detailed analysis of clinical history as well as biochemical studies was carried out to reveal possible pathophysiology. Three pediatric transplant recipients (one HSCT, two kidney transplantation) with findings of hyperkalemia, hyponatremia, and a mild elevation in blood urea nitrogen while on CNIs were recruited. Urinary potassium excretion was diminished while sodium excretion was increased. Plasma aldosterone levels were low, and renin was not increased in response. Primary adrenal insufficiency was ruled out, and hyporeninemic hypoaldosteronism was diagnosed. CNI-related hyperkalemia was detected earlier in case 1, who had HSCT (22 days), than in the second and third cases, who had kidney transplantation (24 and 30 months post-transplantation, respectively). The discrepancy was hypothesized to be explained by higher overall CNI dose due to higher serum target CNI used in HSCT than kidney transplantation. Electrolyte imbalance was reversed upon administration of physiologic dose fludrocortisone (0.05 mg, daily), while fludrocortisone was ceased after CNI withdrawal in case 1, which is additional evidence for the etiological association of CNIs and hyporeninemic hypoaldosteronism. Our three cases strengthen the premise that CNI-related hyperkalemia may be due to hyporeninemic hypoaldosteronism, and the timing and severity may be related to CNI dose. Fludrocortisone is a safe and effective treatment in CNI-related hyperkalemia, providing maintenance of CNIs, which are one of the essential therapeutic agents for pediatric transplantation.

24-h urinary sodium and potassium excretions, plasma metabolomic profiles, and cardiometabolic biomarkers in the United States adults: a cross-sectional study

BackgroundHigh-sodium and low-potassium intakes are associated with a higher risk of hypertension and cardiovascular disease, but there are limited data on the circulating metabolomics profiles of 24-h urinary sodium and potassium excretions in free-living individuals. ObjectivesWe aimed to characterize the metabolomics signatures of a high-sodium and low-potassium diet in a cross-sectional study. MethodsIn 1028 healthy older adults from the Women’s and Men’s Lifestyle Validation Studies, we investigated the association of habitual sodium and potassium intakes measured by 2 to 4 24-h urine samples with plasma metabolites (quantified using liquid chromatography-tandem mass spectrometry) and metabolomic pathways. Our primary exposures were energy-adjusted 24-h urinary sodium excretion, potassium excretion, and sodium-to-potassium ratio, calculated based on energy expenditure derived from the doubly labeled water method. We then assessed the partial correlations of their metabolomics scores, derived from elastic net regressions, with cardiometabolic biomarkers. ResultsHigher sodium excretion was associated with 38 metabolites including higher piperine, phosphatidylethanolamine, and C5:1 carnitine. In pathway analysis, higher sodium excretion was associated with enhanced biotin and propanoate metabolism and enhanced degradation of lysine and branched-chain amino acids (BCAAs). Metabolites associated with higher potassium and lower sodium-to-potassium ratio included quinic acid and proline-betaine. After adjusting for confounding factors, the metabolomics score for sodium-to-potassium ratio positively correlated with fasting insulin (Spearman’s rank correlation coefficient ρ = 0.27), C-peptide (ρ = 0.30), and triglyceride (ρ = 0.46), and negatively with adiponectin (ρ = −0.40), and high-density lipoprotein cholesterol (ρ = −0.42). ConclusionsWe discovered metabolites and metabolomics pathways associated with a high-sodium diet, including metabolites related to biotin, propanoate, lysine, and BCAA pathways. The metabolomics signature for a higher sodium low-potassium diet is associated with multiple components of elevated cardiometabolic risk.

Blood pressure variability in acute stroke: Risk factors and association with functional outcomes at 1 month.

Blood pressure variability, in acute stroke, may be an important modifiable determinant of functional outcome after stroke. In a large international cohort of participants with acute stroke, it was sought to determine the association of blood pressure variability (in the early period of admission) and functional outcomes, and to explore risk factors for increased blood pressure variability. INTERSTROKE is an international case-control study of risk factors for first acute stroke. Blood pressure was recorded at the time of admission, the morning after admission and the time of interview in cases (median time from admission 36.7 h). Multivariable ordinal regression analysis was employed to determine the association of blood pressure variability (standard deviation [SD] and coefficient of variance) with modified Rankin score at 1-month follow-up, and logistic regression was used to identify risk factors for blood pressure variability. Amongst 13,206 participants, the mean age was 62.19 ± 13.58 years. When measured by SD, both systolic blood pressure variability (odds ratio 1.13; 95% confidence interval 1.03-1.24 for SD ≥20 mmHg) and diastolic blood pressure variability (odds ratio 1.15; 95% confidence interval 1.04-1.26 for SD ≥10 mmHg) were associated with a significant increase in the odds of poor functional outcome. The highest coefficient of variance category was not associated with a significant increase in risk of higher modified Rankin score at 1 month. Increasing age, female sex, high body mass index, history of hypertension, alcohol use, and high urinary potassium and low urinary sodium excretion were associated with increased blood pressure variability. Increased blood pressure variability in acute stroke, measured by SD, is associated with an increased risk of poor functional outcome at 1 month. Potentially modifiable risk factors for increased blood pressure variability include low urinary sodium excretion.

Evaluation of Drug-Drug Interaction Between Henagliflozin and Hydrochlorothiazide in Healthy Chinese Volunteers.

Henagliflozin is an original, selective sodium-glucose cotransporter 2 (SGLT2) inhibitor. Hydrochlorothiazide (HCTZ) is a common anti-hypertensive drug. This study aimed to evaluate the potential interaction between henagliflozin and HCTZ. This was a single-arm, open-label, multi-dose, three-period study that was conducted in healthy Chinese volunteers. Twelve subjects were treated in three periods, period 1: 25 mg HCTZ for four days, period 2: 10 mg henagliflozin for four days and period 3: 25 mg HCTZ + 10 mg henagliflozin for four days. Blood samples and urine samples were collected before and up to 24 hours after drug administrations on day 4, day 10 and day 14. The plasma concentrations of henagliflozin and HCTZ were analyzed using LC-MS/MS. The urine samples were collected for pharmacodynamic glucose and electrolyte analyses. Tolerability was also evaluated. The 90% CI of the ratio of geometric means (combination: monotherapy) for AUCτ,ss of henagliflozin and HCTZ was within the bioequivalence interval of 0.80-1.25. For henagliflozin, co-administration increased Css, max by 24.32% and the 90% CI of the GMR was (108.34%, 142.65%), and the 24-hour urine volume and glucose excretion decreased by 0.43% and 19.6%, respectively. For HCTZ, co-administration decreased Css, max by 19.41% and the 90% CI of the GMR was (71.60%, 90.72%), and the 24-hour urine volume and urinary calcium, potassium, phosphorus, chloride, and sodium excretion decreased by 11.7%, 20.8%, 11.8%, 11.9%, 22.0% and 15.5%, respectively. All subjects (12/12) reported adverse events (AEs), but the majority of theses AEs were mild and no serious AEs were reported. Although Css,max was affected by the combination of henagliflozin and HCTZ, there was no clinically meaningful safety interaction between them. Given these results, coadministration of HCTZ should not require any adaptation of henagliflozin dosing. ClinicalTrials.gov NCT06083116.