Estimated Salt Intake Research Articles

Factors Associated With the Use of a Salt Substitute in Rural China

Lowering sodium intake reduces blood pressure and may reduce the risk of cardiovascular diseases. The use of reduced-sodium salt (a salt substitute) may achieve sodium reduction, but its effectiveness may be associated with the context of its use. To identify factors associated with the use of salt substitutes in rural populations in China within the Salt Substitute and Stroke Study, a large-scale cluster randomized trial. This sequential mixed-methods qualitative evaluation, conducted from July 2 to August 28, 2018, in rural communities across 3 provinces in China, included a quantitative survey, collection of 24-hour urine samples, and face-to-face interviews. A random subsample of trial participants, selected from the 3 provinces, completed the quantitative survey (n = 1170) and provided urine samples (n = 1025). Interview respondents were purposively selected from the intervention group based on their different ranges of urinary sodium excretion levels. Statistical analysis was performed from September 18, 2018, to February 22, 2019. The intervention group of the Salt Substitute and Stroke Study was provided with the free salt substitute while the control group continued to use regular salt. Knowledge, attitudes, and behaviors regarding the use of the salt substitute were measured using quantitative surveys, and urinary sodium levels were measured using 24-hour urine samples. Contextual factors were explored through semistructured interviews and integrated findings from surveys and interviews. A total of 1170 individuals participated in the quantitative survey. Among the 1025 participants with successful urine samples, the mean (SD) age was 67.4 (7.5) years, and 502 (49.0%) were female. The estimated salt intake of participants who believed that high salt intake was good for health was higher; however, it was not significantly different (0.84 g/d [95% CI, -0.04 to 1.72 g/d]) from those who believed that high salt intake was bad for health. Thirty individuals participated in the qualitative interviews (18 women [60.0%]; mean [SD] age, 70.3 [6.0] years). Quantitative and qualitative data indicated high acceptability of and adherence to the salt substitute. Contextual factors negatively associated with the use of the salt substitute included a lack of knowledge about the benefits associated with salt reduction and consumption of high-sodium pickled foods. In addition, reduced antihypertensive medication was reported by a few participants using the salt substitute. This study suggests that lack of comprehensive understanding of sodium reduction and salt substitutes and habitual consumption of high-sodium foods (such as pickled foods) were the main barriers to the use of salt substitutes to reduce sodium intake. These factors should be considered in future population-based, sodium-reduction interventions.

Significance of nutrition in hemodialysis patients with peripheral arterial disease evaluated by skin perfusion pressure

BackgroundPeripheral artery disease (PAD) is a serious complication in hemodialysis (HD) patients. Low skin perfusion pressure (SPP) is a useful marker for detecting PAD. Malnutrition is an important cause of intractable complications. We examined the relationship between low SPP and various indicators of nutritional status.MethodsA total of 120 patients on maintenance HD were enrolled for SPP measurement. SPP was measured at the soles of both feet during HD, and patients were divided into low SPP (L-SPP) and normal SPP (N-SPP) groups by 50 mmHg. The following values were determined by averaging four blood samples taken before SPP measurements every 3 months for one year: hemoglobin, total protein, albumin (Alb), total cholesterol, urea nitrogen, creatinine (Cr), potassium, calcium, phosphate, intact parathyroid hormone, iron (Fe), transferrin saturation (T-SAT), and C-reactive protein (CRP). We calculated the percent Cr production rate, dialysis index (Kt/V), normalized protein catabolic rate (nPCR), geriatric nutritional risk index (GNRI), and estimated salt intake using the required formulas. In addition, the age, body mass index, and presence of diabetes mellitus (DM) were compared between both groups along with all other measurements. Data were expressed as the mean ± standard deviation or median with interquartile range as appropriate. Differences in continuous variables between the two groups were analyzed by Student’s t-test or Wilcoxon’s rank-sum test, as appropriate. Multivariate logistic analysis and receiver operating curve (ROC) analysis were performed for significant variables. The results were expressed as odds ratios with respective 95% confidence intervals (CIs).ResultsThe enrolled patients were 82 men and 38 women, with a mean age of 66.9 ± 13.3 years and HD duration of 4.76 (2.13–12.28) years (median interquartile range). Twenty patients belonged to the L-SPP group, suggesting PAD. Comparison between the L-SPP and N-SPP groups showed significant differences in age, Cr, Fe, T-SAT, CRP, nPCR, GNRI, DM, and estimated salt intake. When the GNRI, estimated salt intake, CRP, and DM were applied as independent variables for multiple logistic regression analysis, the GNRI (odds ratio: 0.857, 95% CI 0.781–0.941, p = 0.001), CRP (2.406, 1.051–3.980, p = 0.035), and DM (9.194, 2.497–33.853, p = 0.001) were found to be significant for L-SPP, and a cutoff level of 92.1 (sensitivity 80%, specificity 72%, AUC: 0.742, 95% CI 0.626–0.858, p = 0.001) in the GNRI obtained by ROC was consistent with the risk index in the elderly presented previously.ConclusionsSPP measurement is an essential tool for detecting high-risk PAD in maintenance HD, which is affected by malnutrition, DM, and inflammation. The GNRI is important for the determination of malnutrition.

Association between 24 h Urinary Sodium and Potassium Excretion and Dietary Intake in Japanese Male Adolescent Football Players

High urinary sodium-to-potassium ratio is considered a strong risk factor for hypertension. This study aimed to evaluate urinary excretion of sodium and potassium, and we analyzed these levels associated with dietary intake in Japanese adolescent football players. This cross-sectional study included 120 Japanese male adolescent football players. Over 24 h, urine was collected and measured for creatinine, sodium, and potassium levels. A dietary assessment was performed using a self-administered diet history questionnaire. The study analyzed 79 participants. The mean urinary sodium was 143.2 mmol/day, urinary potassium was 42.8 mmol/day, and the mean urinary sodium-to-potassium ratio was 3.6. Compared with the Japanese Dietary Reference Intakes, the estimated salt intake was 73.4% for the participants who exceeded the sodium intake, and the estimated potassium intake was 73.4% for the participants who did not satisfy it. Multiple regression analysis revealed that milk and dairy product intake was independently and positively associated with urinary potassium (β = 0.252) and independently and negatively associated with the urinary sodium-to-potassium ratio (β = −0.254). Adolescent football players had a high-sodium and low-potassium diet, well above the Japanese Dietary Reference Intakes recommendations. Milk and dairy products could be effective for increasing urinary potassium and decreasing the urinary sodium-to-potassium ratio.

Development of a Method for Estimating Dietary Salt Intake Using the Overnight Urinary Sodium/Potassium Ratio.

Background: There are many patients who need to restrict and assess salt in their diet. However, it is difficult to estimate daily salt intake accurately and easily. Therefore, a method for estimating dietary salt intake using the overnight urinary sodium (Na)/potassium (K) ratio was developed. Methods: The study involved 43 healthy adults (13 males, 30 females). From 2018 to 2020, subjects consumed a salt-adjusted diet for 11 - 30 days continuously, and overnight urine was collected daily. Using the previous day’s salt intake as the objective variable, an equation for estimating the salt intake was developed using a general linear model. To verify the accuracy of the estimating equation, the estimated salt intake of the previous day was calculated using our equation and Tanaka’s equation, which is an estimating equation from spot urine widely used in clinical practice and epidemiological studies to estimate dietary salt intake, and they were compared with the actual salt intake. Results: The results of the analysis showed that model 1 (previous day’s salt intake (g) = 3.62 + 0.64 × urinary Na/K ratio + 0.18 × conductivity (mS/cm) - 0.43 × sex (male 0, female 1)) was the optimal model. Then, salt intake was estimated using model 1 and Tanaka’s equation, and compared with actual salt intake. The Pearson’s product-moment correlation coefficient between the actual and estimated salt intake was r = 0.618 (P < 0.001) and r = 0.573 (P < 0.001) for model 1 estimates and Tanaka’s equation estimates, respectively. The percentages of errors within ±30% from the actual salt intake were 64.2% and 58.4% for model 1 and Tanaka’s equation, respectively. Conclusion: An equation for estimating salt intake was developed using the Na/K ratio and conductivity of overnight urine. Although the applicability of this method to hypertensive patients and the elderly has not been studied and needs to be clarified in the future, the estimating equation developed is simple and may be a useful method for daily monitoring of dietary salt intake. J Clin Med Res. 2021;13(9):479-486 doi: https://doi.org/10.14740/jocmr4596

Validation of Self-Monitoring Devices Supporting Sodium Intake Reduction: An Experimental Feeding Study Using Standardized Low-Salt and High-Salt Meals among Healthy Japanese Volunteers

Introduction: Although several approaches for approximating daily Na intake and the Na/K ratio using casual urine are available, the most useful method remains unclear during daily practice and at home. Methods: Twenty-seven participants measured their casual urinary Na/K ratio repeatedly using a Na/K ratio monitor and also measured overnight urine once daily using a monitoring device which delivers on-site feedback to estimate their salt intake under unrestricted, low-salt (LS) (6 g/day), and high-salt (HS) (12 g/day) diets. Results: The monitoring method utilizing overnight urine to estimate daily Na remained insensitive, resulting in significant overestimation during the LS diet and underestimation during the HS diet periods; estimated salt intake during the LS and HS diet periods plateaued at 7–8 g/day and 9–10 g/day within 3 day; mean estimated salt intake was 11.3 g/day, 7.9 g/day, and 9.8 g/day on the last day of the unrestricted, LS, and HS diets; the coefficient of variation (CV) of the estimated Na intake was 0.23 and 0.17 in the latter half of the low- and high-salt diet periods, respectively. The mean urinary Na/K molar ratio was 5.6, 2.5, and 5.3 on the last day of the unrestricted, LS, and HS diets; the CV of the daily mean Na/K ratio was 0.41 and 0.36 in the latter half of the LS and HS diet periods, respectively. The urinary Na/K ratio during the LS and HS diet periods plateaued within 2 days. The monitoring method based on the daily mean of the casual urinary Na/K ratio reflected the actual change in Na intake, and the estimated value tracked the actual changes in salt intake with smaller difference than the overnight urine estimates when using the estimation coefficient set at 2; estimated salt intake during the LS and HS diet periods plateaued at 5–6 g/day and 10–12 g/day within 2–3 day; mean estimated salt intake was 11.0 g/day, 5.7 g/day, and 10.7 g/day on the last day of the unrestricted, LS, and HS diets, respectively. Discussion/Conclusion: Estimates of daily Na intake derived from overnight urine may remain insensitive during dietary interventions. The urinary Na/K ratio reflects the actual change in Na intake during dietary modification and may serve as a practical marker, particularly during short-term interventions. Conversion from the urinary Na/K ratio to estimated salt intake may be useful, if the coefficient was set appropriate by further investigations.

Development of a Method for Estimating Dietary Salt Intake Using the Overnight Urinary Sodium/Potassium Ratio.

BackgroundThere are many patients who need to restrict and assess salt in their diet. However, it is difficult to estimate daily salt intake accurately and easily. Therefore, a method for estimating dietary salt intake using the overnight urinary sodium (Na)/potassium (K) ratio was developed.MethodsThe study involved 43 healthy adults (13 males, 30 females). From 2018 to 2020, subjects consumed a salt-adjusted diet for 11 - 30 days continuously, and overnight urine was collected daily. Using the previous day’s salt intake as the objective variable, an equation for estimating the salt intake was developed using a general linear model. To verify the accuracy of the estimating equation, the estimated salt intake of the previous day was calculated using our equation and Tanaka’s equation, which is an estimating equation from spot urine widely used in clinical practice and epidemiological studies to estimate dietary salt intake, and they were compared with the actual salt intake.ResultsThe results of the analysis showed that model 1 (previous day’s salt intake (g) = 3.62 + 0.64 × urinary Na/K ratio + 0.18 × conductivity (mS/cm) - 0.43 × sex (male 0, female 1)) was the optimal model. Then, salt intake was estimated using model 1 and Tanaka’s equation, and compared with actual salt intake. The Pearson’s product-moment correlation coefficient between the actual and estimated salt intake was r = 0.618 (P < 0.001) and r = 0.573 (P < 0.001) for model 1 estimates and Tanaka’s equation estimates, respectively. The percentages of errors within ±30% from the actual salt intake were 64.2% and 58.4% for model 1 and Tanaka’s equation, respectively.ConclusionAn equation for estimating salt intake was developed using the Na/K ratio and conductivity of overnight urine. Although the applicability of this method to hypertensive patients and the elderly has not been studied and needs to be clarified in the future, the estimating equation developed is simple and may be a useful method for daily monitoring of dietary salt intake.

Association of Estimated Salt and Miso Intake with the Prevalence of Obesity in People with Type 2 Diabetes: A Cross-Sectional Study.

Salt intake is often estimated by the amount of sodium excreted in urine, and miso has been reported to increase it. This cross-sectional study investigated the relationship between obesity and high estimated salt intake with and without habitual miso consumption. Estimates of salt intake (g/day) were calculated using urinary sodium excretion, and a high estimated intake was defined as greater than the median amount of 9.5 g/day. Participants were divided into four groups based on estimated salt intake and miso consumption. Among 300 people, the proportions of obesity were 77.8% (n = 14/18), 40.2% (n = 53/132), 26.0% (n = 33/127), and 34.8% (n = 8/23) in the (+/−), (+/+), (−/+), and (−/−) groups of high estimated salt intake/habitual miso consumption, respectively. Compared with the (+/−) group, the adjusted odds ratios for obesity were 0.07 (95% confidence interval (CI): 0.02–0.26, p < 0.001), 0.16 (95% CI: 0.03–0.76, p = 0.022), and 0.14 (95% CI: 0.04–0.51, p = 0.003) in the (−/+), (−/−), and (+/+) groups, respectively. The presence of obesity was not much higher in people with high estimated salt intake with habitual miso consumption than that in people without. Clinicians should be aware that miso consumption promotes salt excretion, which may lead to an apparently higher estimated salt intake than actual.

Relationship between salt intake and sleep disordered breathing in dialysis patients.

The prevalence of sleep disordered breathing is high in patients with end-stage renal disease. Salt intake is related to the severity of obstructive sleep apnea in patients with resistant hypertension and hyperaldosteronism. We investigated the relationship between salt intake and sleep disordered breathing in patients on maintenance hemodialysis. We studied 128 dialysis outpatients (mean age 63 ± 11years) who were followed at Kokura Daiichi Hospital. We estimated each patient's salt intake using an InBody S10 body composition analyzer and measured the 3% oxygen desaturation index (ODI) during sleep using a Pulsewatch: PMP-200 GplusX. The average estimated salt intake was 8.0 ± 2.6g/day, and the median value of that was 7.5g/day. Blood pressure (BP) before and after dialysis were 140 ± 18/78 ± 11 and 127 ± 13/72 ± 8mmHg, respectively. The geometric average number of 3% ODI was 7.1, and sleep disordered breathing was detected in 30% of all subjects. The patients with ≥ 7.5g/day salt intake were younger and more frequently male and had higher body mass index (BMI) and BP before dialysis compared to those with salt intakes < 7.5g/day. Patients with ≥ 7.5g/day salt intake had a significantly higher geometric average number of 3% ODI; however, this relationship became weaker after adjusting for BMI. The same relationship was obtained for the prevalence of sleep disordered breathing. The prevalence of sleep disordered breathing in patients on maintenance hemodialysis was high, and the sleep disordered breathing was associated with salt intake and BMI.

Randomized Controlled Trial of Simple Salt Reduction Instructions by Physician for Patients with Type 2 Diabetes Consuming Excessive Salt.

Objectives: We verified the clinical usefulness of an approach method in which a physician gives simple salt reduction instructions during outpatient visits to patients with type 2 diabetes. Methods: This study was an open-blind, randomized controlled trial. Subjects were outpatients with type 2 diabetes whose estimated salt intake using spot morning urine sample exceeded the target of salt intake. The control group (CG) was notified only of the current salt intake, whereas the intervention group (IG) was given the brief salt reduction instruction by a physician in addition to the information regarding their current salt intake. Results: The change in estimated salt intake was −0.6 g (from 10.1 to 9.5 g, p = 0.029) in the CG after 8 weeks, and −0.9 g (from 10.1 to 9.2 g, p = 0.001) in the IG, although there were no significant differences between them (p = 0.47). After 24 weeks, both groups no longer differed significantly from the baseline. In addition, multivariate linear regression analyses indicated that high salt intake and low estimated glomerular filtration rate at baseline were significantly associated with salt reduction after 8 weeks. Conclusions: Salt-reducing effects were observed after 8 weeks in both the IG and CG, but no significant difference was observed. Moreover, patients with high salt intake and renal disfunction may be more effective in accepting salt reduction instructions. Making patients aware of the importance of salt reduction through a physician is effective for continuous salt reduction, and it is important to continue regular and repetitive guidance.

Knowledge, Attitudes, and Behavior Towards Salt Intake and Association With 24-hour Urinary Sodium Excretion in an Adult Population Cohort in Uruguay

ObjectivesTo examine the association between knowledge, attitudes and behavior towards salt use and its consumption estimated by urinary sodium excretion in a population adult cohort from Uruguay (Genotype Phenotype and Environment of Hypertension Study - GEFA-HT-UY). MethodsParticipants [n = 243; age 18–89y (min-max); 61.9% women], provided a single 24-hour urine sample validated according to volume and creatinine excretion. A questionnaire describing knowledge, attitudes and behaviors (KAB) was adapted from the WHO/PAHO protocol for population level sodium determination where participants answered on a range of scales. Anthropometric and blood pressure measurements were also taken. Associations between KAB categories and estimated salt intake were examined by general linear models, adjusted for sex, age tertiles and body mass index (BMI) categories. ResultsConsidering all participants, 35.8% were hypertensive (77% on antihypertensive treatment). Systolic/diastolic blood pressure was 125.6 ± 23.4/79.7 ± 9.9 mmHg, with no difference between sexes. Estimated salt intake was 7.8 ± 3.6 g (3116 ± 1433 mg sodium), higher in men (8.9 ± 3.9 g) compared to women (7.3 ± 3.3 g) (P = 0.0013). Salt intake decreased with age tertiles (P = 0.0001), and increased with BMI categories (P = 0.0067). The majority (88.5%) of participants acknowledge that a high salt diet may cause serious health problems, 92.2% were unaware of WHO salt intake recommendation (<5 g/d) and 78.6% had intake over that limit. Only 12.4% considered they consumed “too much salt”. Although 74.7% reported that limiting salt intake was important for their health, only 56% reported taking regular actions to control its intake. No difference in salt intake was found between participants who considered they use salt “too much” (8.5 ± 0.62 g), “the right amount” (7.9 ± 0.28 g), or “too little” (7.6 ± 0.52 g) (P = 0.56). However, those who reported following a healthy diet had 1.4g lower salt intake than those who reported not doing so (P = 0.016). There was no difference in salt intake between those who reported using/not using salt when cooking (P = 0.65), and adding/not adding salt to food at table (P = 0.087). ConclusionsNo associations were found between knowledge, attitudes and behaviors towards salt use and intake. Perceived salt consumption underestimated salt intake. Funding SourcesCSIC, ANII, Uruguay.

Comparing Three Approaches to Salt Intake Assessment Among Lactating Women in Rural Cambodia

ObjectivesMonitoring population salt intake is a critical component of implementing salt fortification programs. In Cambodia, salt is being considered as a vehicle for thiamine fortification to prevent infantile beriberi among breastfed infants. However, salt intake among lactating mothers is not known. The gold standard for assessing sodium intake is repeat 24-hr urinary sodium concentrations. This method has logistical barriers, especially in low-resource settings, and other methods have not been trialed in this population. Here we compare three methods of assessing salt intake in lactating Cambodian women: repeat 24-hr urinary sodium concentrations (USC), repeat 12-hr observed weighed intake records (OWIR), and household salt disappearance (HSD). MethodsData from trial: NCT03616288. Salt intake was assessed using the three methods in a subsample of lactating women (n = 104) between 8 and 22 weeks postpartum. Women were asked to collect two 24-hour urine samples within 7 days. Repeat 12-hr OWIR were collected from women. Household salt disappearance was recorded fortnightly, and was divided by the number of household members to estimate individual intakes. Descriptive household salt use was also recorded. Differences in estimated salt intake from each method were compared using a Kruskal-Wallis test. ResultsMean (95%CI) estimated salt intakes from repeat 24-hr USC, repeat 12-hr OWIR, and HSD were: 9.0 (8.3, 9.8) g/day, 9.1 (7.9, 10.3) g/day, and 10.9 (9.8, 11.9) g/day, respectively. Estimated intakes from HSD were significantly higher than both 24-hr USC (p = 0.009) and 12-hr OWIR (p = 0.002). Estimated intakes from 24-hr USC and 12-hr OWIR were not statistically different (p = 0.6). Salt was being used for purposes other than consumption, such as cleaning fish and vegetables, in 26% of fortnightly visits. ConclusionsRepeat 24-hr USC and 12-hr OWIR are both acceptable and logistically feasible methods of salt intake assessment among lactating women in rural Cambodia. While HSD is a less resource-intensive approach, this method over-estimated salt intake. Salt being used for purposes other than consumption may contribute to over-estimation using this method. Funding SourcesBill & Melinda Gates Foundation, New York Academy of Sciences, Canadian Institutes of Health Research, Research Nova Scotia.

The association of von willebrand factor and its cleaving protease (ADAMTS13) with health behaviours in young black and white adults: the African-PREDICT study

To reduce cardiovascular risks imposed by Von Willebrand factor (vWF) and ADAMTS13 from young ages, knowledge on health behaviours that may affect their concentrations is essential. We therefore determined whether circulating vWF antigen and ADAMTS13 associate with health behaviours. We included 1196 black and white healthy adults aged 20-30 years and used questionnaires for socio-economic, tobacco and alcohol use data. vWF:Ag was measured from citrated samples and ADAMTS13, cotinine and gamma-glutamyl transferase (GGT) from serum. Salt intake was estimated from 24-hour urine and body mass index (BMI) was calculated. Black adults had higher vWF:Ag and lower ADAMTS13 levels compared to whites (all p < 0.001). In multiple regression analyses in the total group, vWF:Ag associated positively with BMI (p = 0.037), while ADAMTS13 associated negatively with BMI (p = 0.016) and cotinine (p = 0.029); and positively with GGT (p = 0.002). When exploring within each ethnic group, vWF:Ag associated positively with estimated salt intake (p = 0.043) only in blacks. In whites, vWF:Ag associated positively with BMI (p = 0.023) while ADAMTS13 associated positively with GGT (p = 0.003) and negatively with cotinine (p = 0.041). Young black adults may have an increased thrombotic risk due to higher vWF and lower ADAMTS13. The ethnic-specific associations observed may have implications for public health initiatives to improve cardiovascular outcomes.

EARLY EVIDENCE FOR THE EFFECTIVENESS OF SOUTH AFRICA'S LEGISLATION ON SALT RESTRICTION IN FOODS: THE AFRICAN-PREDICT STUDY

Objective: South Africa was one of the first countries to adopt mandatory regulation in 2016 to lower the salt content of a wide range of processed foods. To assess the effectiveness of this regulation, we determined the change in salt intake of young adults over a mean follow-up time of 4.56-years spanning the implementation of the regulation. Since young populations have a higher salt intake, salt reduction may have a greater long-term impact as a preventative strategy in this age group. Design and method: This study included baseline (N = 668; aged 24.9 ± 3 years; 47.8% black; 40.7% men) and follow-up data for the first 311 participants (aged 29.9 ± 3.09 years; 51.1% black; 43.4% men) tracked over time as part of the African-PREDICT study. Participants had baseline data before 30th June 2016, and follow-up from 2018 - 2020. Estimated salt intake at baseline and follow-up was calculated from 24-hour urinary sodium excretion. Results: The median salt intake of the population (N = 668) at baseline was 7.88 g/day (IQR: 5.67). In those followed (N = 311), salt intake reduced from baseline [median (IQR): 7.91 g/day (5.83)] to follow-up [median (IQR): 7.26 g/day (5.30)] in the total group [median difference (IQR): -0.82 g/day (7.02); p = 0.007], with a greater reduction observed in black adults [N = 159, median difference (IQR): -1.35 g/day (7.91); p = 0.003]. Reduced salt intake was more pronounced in black adults from a low (p = 0.007) and middle socio-economic status (p = 0.009), compared to a high socio-economic status (p = 0.27). Conclusions: Our preliminary findings suggest that South Africa's mandatory salt reduction regulation for processed foods has been effective in lowering salt intake in young adults by a magnitude of ∼0.82 g salt/day. Our study supports the effectiveness of “upstream” sodium reduction interventions at population level that may impact on the health and economic burden of countries.

ASSOCIATIONS OF SODIUM INTAKE WITH CENTRAL HEMODYNAMICS AND CHANGES IN VASCULAR STRUCTURE AND FUNCTION AT HIGH ALTITUDE LOCALITIES

Objective: To investigate the associations of sodium intake with central hemodynamics and changes in vascular structure and function at high altitude localities. Design and method: From December 2018 to January 2019, a total of 383 monks who participated in cardiovascular risk factors screening were enrolled in four temples around Luhuo County, Ganzi Tibetan Autonomous Prefecture with an average elevation of 3,800 meters. Questionnaire, physical examination, blood and urine examination, electrocardiogram, echocardiography, intima-media thickness (IMT), Brachial ankle pulse wave velocity (BaPWV), Ankle brachial index (ABI), Central systolic blood pressure (CSBP), Central diastolic blood pressure (CDBP), Central pulse pressure (CPP), Central mean arterial pressure (CMAP), Augmentation pressure (AP), Augmentation index (AI) and other tests were performed on all participants. Estimated 24-hour urinary sodium excretion was measured by the Kawasaki formula using the urinary sodium/urinary creatinine ratio of the second morning fasting urine. Pearson correlation and multiple linear regression were used to analyze the associations between 24 h urinary sodium and central arterial hemodynamic parameters and BaPWV and IMT. Results: 1. The estimated 24 h urinary sodium excretion in the temple was (5.26 ± 1.61)g, and the estimated salt intake was (13.36 ± 4.09)g. There was no significant correlation between 24 h urinary sodium and CDBP, AP and IMT (P &gt; 0.05). After gender, age, CSBP, body Mass Index (BMI), fasting blood glucose (FBG), estimated glomerular filtration rate (eGFR), triglycerides (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) were adjusted, 24 h urine sodium was positively correlated with CSBP (P = 0.018) and CPP (P &lt; 0.001). After adjusting for gender, age, CSBP, BMI, eGFR, FBG, TG, HDL, LDL, 24 h urinary sodium was significantly negatively correlated with AIX75 and BaPWV (P = 0.028,P &lt; 0.001, respectively). The line graph of means across the 24 h urinary sodium quartiles and the cubic fitting curve showed that the associations between 24 h urinary sodium excretion with AIX75 and BaPWV presented an approximate ’J’ shape. Conclusions: 24 h urinary sodium was positively correlated with CSBP and CPP in the monks in this region. The associations between 24 h urinary sodium with AIX75 and BaPWV resembled a ’J’ shape.

Factors associated with salt intake in the Brazilian adult population: National Health Survey.

This paper aims to identify the factors associated with high salt intake in the Brazilian adult population. This is a cross-sectional study with 8,083 adults participating in the National Health Survey (PNS, 2014/15). Salt intake was based on the estimation of 24-hour urinary sodium calculated from the sodium/creatinine ratio in spot urine samples. The highest quartile of the distribution was considered high salt intake. The relationship between high salt consumption and sociodemographic factors, lifestyles, morbidity, and self-rated health status was analyzed by calculating the crude prevalence ratios and the prevalence ratios adjusted for age and gender. Approximately 28.1% had an estimated salt intake higher than 10.56 g/day. Overweight (Adjusted Prevalence Ratio; 95%CI - PRadj 1.23; 1.09-1.39), obesity (PRadj 1.61; 1.43-1.83), and diabetes (PRadj 1.36; 1.17-1.58) were positively associated with high salt intake. Female gender (PRadj 0.73; 0.66-0.80), high schooling level (PRadj 0.88; 0.79-0.99), living in the North and chronic kidney disease (PRadj 0.71; 0.56-0.90) were protective factors. Salt consumption is elevated nationwide and in all population subgroups, requiring coordinated actions.

Assessment of salt intake to consider salt as a fortification vehicle for thiamine in Cambodia.

Thiamine deficiency is a public health issue in Cambodia. Thiamine fortification of salt has been proposed; however, the salt intake of lactating women, the target population, is currently unknown. We estimated salt intakes among lactating women (<6 months postpartum) using three methods: repeat observed‐weighed intake records and 24‐h urinary sodium excretions (n = 104), and household salt disappearance (n = 331). Usual salt intake was estimated by adjusting for intraindividual intakes using the National Cancer Institute method, and a thiamine salt fortification scenario was modeled using a modified estimated average requirement (EAR) cut‐point method. Unadjusted salt intake from observed intakes was 9.3 (8.3–10.3) g/day, which was not different from estimated salt intake from urinary sodium excretions, 9.0 (8.4–9.7) g/day (P = 0.3). Estimated salt use from household salt disappearance was 11.3 (10.7–11.9) g/person/day. Usual (adjusted) salt intake from all sources was 7.7 (7.4–8.0) g/day. Assuming no stability losses, a modeled fortification dose of 275 mg thiamine/kg salt could increase thiamine intakes from fortified salt to 2.1 (2.0–2.2) mg/day, with even low salt consumers reaching the EAR of 1.2 mg/day from fortified salt alone. These findings, in conjunction with future sensory and stability research, can inform a potential salt fortification program in Cambodia.

Estimated salt intake and risk of atrial fibrillation in a prospective community-based cohort.

IntroductionHypertension predisposes to atrial fibrillation (AF) – a major risk factor for ischaemic stroke. Since a high dietary salt consumption is associated with hypertension, we investigated the association between urinary sodium excretion as a marker for dietary sodium intake and risk of new‐onset AF in community‐dwelling adults.MethodThe UK Biobank includes 40‐ to 69‐year‐old British residents recruited 2006–2010. Participants were divided into sex‐specific quintiles according to 24‐hour sodium excretion estimated based on spot samples with the Kawasaki equation. We excluded participants with AF at baseline. Cox regression adjusted for cardiovascular risk factors was used to assess associations with risk of AF, using the third quintile as reference.ResultsA total of 257 545 women and 215 535 men were included. During up to 10 years' follow‐up, 2221 women and 3751 men were diagnosed with AF. There was a tendency for an increased risk of AF in the lowest and highest quintiles of estimated daily salt intake in both women and men. In the fully adjusted model, significant associations were seen amongst men in the lowest and highest quintiles of sodium excretion (hazard ratio, HRQv1, 1.20; 95% CI, 1.08–1.32, P < 0.001, and HRQv5 1.15, 95% CI, 1.03–1.27, P = 0.011).ConclusionWe found evidence for a U‐shaped association between estimated daily salt intake and AF risk amongst men. A suggestive J‐shaped association in women was not statistically confirmed, but analyses were likely underpowered. Our results suggest that above a certain physiological minimum level progressively higher salt intake is associated with increasing risk of AF.

Associations of sodium intake with central hemodynamics and changes in vascular structure and function at high altitude localities

Abstract Objectives To investigate the associations of sodium intake with central hemodynamics and changes in vascular structure and function at high altitude localities. Methods A total of 383 Buddhists were enrolled in four temples with an average elevation of 3,800 meters from December 2018 to January 2019. Estimated 24-hour urinary sodium excretion was measured by the Kawasaki formula using the urinary sodium/creatinine ratio of the second fasting spot urine in the morning. Central hemodynamics, including central systolic blood pressure (CSBP), central diastolic blood pressure (CDBP), central pulse pressure (CPP), central mean arterial pressure (CMAP), augmentation pressure (AP), augmentation index (AI), were evaluated by applanation tonometry using the SphygmoCor analyzer. Vascular structure and function were quantified by carotid intima media thickness (cIMT) and brachial ankle pulse wave velocity (BaPWV), respectively. Pearson correlation and multiple linear regression were used to analyze the associations between 24h urinary sodium with central arterial hemodynamic parameters, cIMT and BaPWV. Results The estimated 24h urinary sodium excretion of the Buddhists in such area was (5.26±1.61)g and the estimated salt intake was (13.36±4.09)g. There was no significant correlation between 24h urinary sodium with CDBP, AP and cIMT (P&amp;gt;0.05). After adjusting for gender, age, CSBP, body mass index (BMI), fasting blood glucose (FBG), estimated glomerular filtration rate (eGFR), triglycerides (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL), the estimated 24h urine sodium was positively correlated with CSBP (β=1.313, P=0.018) and CPP (β=1.311, P&amp;lt;0.001), the estimated 24h urinary sodium was significantly negatively correlated with AIX75 and BaPWV (β=−1.124, P=0.028 and β=−37.530, P&amp;lt;0.001, respectively). The line graph of means across the 24h urinary sodium quartiles and the cubic fitting curve showed that the associations between 24h urinary sodium excretion with AIX75 and BaPWV presented an approximate “J” shape. Conclusions 24h urinary sodium was positively correlated with CSBP and CPP and negatively correlated with AIX75 and BaPWV in the Buddhists in this high altitude area. The associations between 24h urinary sodium with AIX75 and BaPWV resembled a “J” shape. Funding Acknowledgement Type of funding source: None

An impact of dietary intervention on blood pressures among diabetic and/or hypertensive patients with high cardiovascular disorders risk in northern Thailand by cluster randomized trial.

BackgroundGlobal sodium intake remains above the recommended levels to control blood pressure (BP). We aimed to evaluate the efficacy of a dietary intervention on BP through salt reduction among community‐dwelling participants with high risk of cardiovascular disorders (CVD).MethodsThis cluster randomized trial (February 2012 to January 2013) included cooking instruction using the pocket salt meter among patients with diabetes and/or hypertension who were treated at health center in Thailand. Based on health centers, 8 clusters of eligible participants were randomly allocated to the 4 intervention and 4 control groups. Dietary intervention was performed at baseline, 1 month, and 3 months in intervention group. In both groups, systolic and diastolic BPs, and estimated 24 hours salt intake based on overnight urine samples were measured at baseline, 6 months, and 12 months.ResultsA total of 753 participants were enrolled (374 in the intervention group and 379 in the control group). In the mixed‐effects model, there were significant difference in SBP and estimated salt intake after adjusting covariates at 6 months (adjusted differences between groups [95% CI]; −7.55 [−5.61 to −9.49] mm Hg P < .01; −0.66 [−0.40 to −0.92] g/day P = .03). However, these differences were not observed at 12 months (adjusted differences between groups [95% CI]; −1.83 [0.34 to −4.00] mm Hg P = .48; −0.42 [−0.17 to −0.67] g/day P = .16). There were no differences in DBP in both follow‐ups.ConclusionsThese results may suggest the effectiveness of a visually based dietary intervention targeting salt intake reduction in short term, but the effectiveness discontinued in long term.Clinical trial number: The International Standard Randomized Controlled Trial Number Register (ISRCTN39416277) on January 3, 2012.

Salt, but not protein intake, is associated with accelerated disease progression in autosomal dominant polycystic kidney disease

In autosomal dominant polycystic kidney disease (ADPKD), there are only scarce data on the effect of salt and protein intake on disease progression. Here we studied association of these dietary factors with the rate of disease progression in ADPKD and what the mediating factors are by analyzing an observational cohort of 589 patients with ADPKD. Salt and protein intake were estimated from 24-hour urine samples and the plasma copeptin concentration measured as a surrogate for vasopressin. The association of dietary intake with annual change in the estimated glomerular filtration rate (eGFR) and height adjusted total kidney volume (htTKV) growth was analyzed with mixed models. In case of significant associations, mediation analyses were performed to elucidate potential mechanisms. These patients (59% female) had a mean baseline age of 47, eGFR 64 mL/min/1.73m2 and the median htTKV was 880 mL. The mean estimated salt intake was 9.1 g/day and protein intake 84 g/day. During a median follow-up of 4.0 years, eGFR was assessed a median of six times and 24-hour urine was collected a median of five times. Salt intake was significantly associated with annual change in eGFR of-0.11 (95% confidence interval 0.20 --0.02] mL/min/1.73m2) per gram of salt, whereas protein intake was not (-0.00001 [-0.01 - 0.01] mL/min/1.73m2) per gram of protein). The effect of salt intake on eGFR slope was significantly mediated by plasma copeptin (crude analysis: 77% mediation, and, adjusted analysis: 45% mediation), but not by systolic blood pressure. Thus, higher salt, but not higher protein intake may be detrimental in ADPKD. The substantial mediation by plasma copeptin suggests that this effect is primarily a consequence of a salt-induced rise in vasopressin.