Diet quality as assessed by the healthy eating index-2020 among different smoking status: an analysis of national health and nutrition examination survey (NHANES) data from 2005 to 2018

BACKGROUND

Combining smoking with poor eating habits significantly elevates the risk of chronic illnesses and early death. Understanding of how dietary quality shifts post-smoking cessation remains limited. The objective of this study is to examine dietary quality - using Healthy Eating Index (HEI - 2020) and its 13 components, among current, former, and never smokers, and particularly the impact of quitting and the duration of cessation on dietary habits.

METHODS

A cross-sectional analysis of 31,569 adults from the National Health and Nutrition Examination Survey (NHANES) 2005-2018 was conducted. Dietary quality was assessed using HEI-2020 scores, which were determined by NIH developed - simple HEI scoring algorithm per person. Smoking status was categorized into current, former, and never smokers, with further subdivisions for current (heavy/light smokers) and former smokers (duration post-cessation). Descriptive analysis and multiple regression models weighted to represent the US population were performed.

RESULTS

The current smoking rate was 19.4%, with a higher prevalence in males (22.5%) than females (17.5%). Current smokers reported statistically significantly lower HEI total score than both former and never smokers. Former smokers exhibited HEI scores similar to those of never smokers. The adjusted HEI total scores for current, former, and never smokers were 49.2, 54.0, and 53.3, respectively, with a statistically significant difference (p < 0.001). Moreover, light smokers had better total HEI score than heavy smokers (46.8 vs. 50.8, p < 0.001, respectively), but former and never smokers scored even higher. Quitting smoking immediately improved dietary quality, with former smokers reaching the dietary levels of never smokers within 5-10 years (53.8 vs. 53.3, p > 0.05, respectively). Compared to current smokers, former smokers tended to consume more beneficial foods (e.g., fruits, vegetables, greens and beans, whole grains, proteins, and fatty acids), while also consuming more sodium and less added sugar.

CONCLUSIONS

Current smokers, particularly heavy smokers, exhibit poorer dietary habits than former and never smokers. The dietary quality of former smokers aligns with never smokers over time, highlighting the positive impact of smoking cessation on diet. This has implications for reducing chronic disease risks associated with poor diet and smoking.

Effect of High Sodium Intake on Gut Tight Junctions' Structure and Permeability to Bacterial Toxins in a Rat Model of Chronic Kidney Disease

INTRODUCTION

Uremic toxicity changes the gut structure and permeability, allowing bacterial toxins to translocate from the lumen to the blood during chronic kidney failure (CKD). Clinical fluid overload and tissue edema without uremia have similar effects but have not been adequately demonstrated and analyzed in CKD.

AIMS

To investigate the effect of sodium intake on the plasma concentration of gut-derived uremic toxins, indoxyl sulfate (IS), and p-cresyl sulfate (pCS) and the expression of genes and proteins of epithelial gut tight junctions in a rat model of CKD.

METHODS

Sham-operated (control group, CG) and five-sixths nephrectomized (5/6Nx) Sprague-Dawley rats were randomly assigned to low (LNa), normal (NNa), or high sodium (HNa) diets., Animals were then sacrificed at 8 and 12 weeks and analyzed for IS and pCS plasma concentrations, as well as for gene and protein expression of thigh junction proteins, and transmission electron microscopy (TEM) in colon fragments.

RESULTS

The HNa 5/6Nx groups had higher concentrations of IS and pCS than CG, NNa, and LNa at eight and twelve weeks. Furthermore, HNa 5/6Nx groups had reduced expression of the claudin-4 gene and protein than CG, NNa, and LNa. HNa had reduced occludin gene expression compared to CG. Occludin protein expression was more reduced in HNa than in CG, NNa, and LNa. The gut epithelial tight junctions appear dilated in HNa compared to NNa and LNa in TEM.

CONCLUSION

Dietary sodium intake and fluid overload have a significant role in gut epithelial permeability in the CKD model.

pylori infection on gastric cancer survival in Korea

BACKGROUND

Double-strand break repair protein (RAD50) gene plays important roles in genomic integrity, DNA double-strand break repair, cell cycle checkpoint activation, telomere maintenance, and meiotic recombination. The risk allele of RAD50 may negatively affect cancer by reducing the DNA repair capacity. Additionally, Sodium intake and Helicobacter pylori (H. pylori) infection are major risk factors for gastric cancer (GC). Our study investigated the association between polymorphisms in RAD50 gene and the risk of GC case-fatality. We evaluated whether the association differed with sodium intake or H. pylori infection.

METHODS

We enrolled 490 patients from two hospitals between 2002 and 2006. Their survival or death was prospectively followed up until December 31, 2016, through a review of medical records and telephone surveys. The GC survival was assessed using the Cox proportional hazards regression analysis.

RESULTS

In 319 GC cases, the total person-years were 1928.3, and the median survival years was 5.4 years. A total of 137 GC deaths were recorded. Our fully adjusted model showed that the GG type of RAD50 rs17772583 polymorphism is significantly associated with an increased risk of GC case-fatality (hazard ratio [HR] = 2.20, 95% confidence interval [CI] = 1.28-3.77) compared to that associated with the homozygous AA type. In the high sodium intake group, patients with the GG type of RAD50 rs17772583 showed a significantly higher GC case-fatality (HR = 8.61, 95% CI = 2.58-26.68) than that of patients with homozygous AA type. In the positive-H. pylori infection group, patients with GG-type RAD50 rs17772583 showed a significantly higher GC case-fatality (HR = 10.11, 95% CI = 2.81-36.35) than that of with AA homozygotes.

CONCLUSIONS

Patients with GG-type RAD50 rs17772583, high sodium intake, or a positive-H. pylori infection are at a significantly increased risk of GC case-fatality compared to that associated with the absence of these risk factors.

Sodium, potassium intake, and all-cause mortality: confusion and new findings

BACKGROUND

The World Health Organization (WHO) has established recommended daily intakes for sodium and potassium. However, there is currently some controversy regarding the association between sodium intake, potassium intake, the sodium-to-potassium ratio, and overall mortality. To assess the correlations between sodium intake, potassium intake, the sodium-to-potassium ratio, and overall mortality, as well as the potential differences in sodium and potassium intake thresholds among different population groups, we analyzed data from NHANES 2003-2018.

METHODS

NHANES is an observational cohort study that estimates sodium and potassium intake through one or two 24-h dietary recalls. Hazard ratios (HR) for overall mortality were calculated using multivariable adjusted Cox models accounting for sampling design. A total of 13855 out of 26288 participants were included in the final analysis. Restricted cubic spline analyses were used to examine the relationship between sodium intake, potassium intake, and overall mortality. If non-linearity was detected, we employed a recursive algorithm to calculate inflection points.

RESULTS

Based on one or two 24-h dietary recalls, the sample consisted of 13,855 participants, representing a non-institutionalized population aged 40-80 years, totaling 11,348,771 person-months of mean follow-up 99.395 months. Daily sodium intake and daily potassium intake were inversely associated with all-cause mortality. Restrictive cubic spline analysis showed non-linear relationships between daily sodium intake, potassium intake, sodium-potassium ratio, and total mortality. The inflection point for daily sodium intake was 3133 mg/d, and the inflection point for daily potassium intake was 3501 mg/d, and the inflection point for daily sodium-potassium ratio intake was 1.203 mg/mg/d. In subgroup analyses, a significant interaction was found between age and high sodium intake, which was further confirmed by the smooth curves that showed a U-shaped relationship between sodium intake and all-cause mortality in the elderly population, with a inflection point of 3634 mg/d.

CONCLUSION

Nonlinear associations of daily sodium intake, daily potassium intake and daily sodium-potassium ratio intake with all-cause mortality were observed in American individuals. The inflection point for daily sodium intake was 3133 mg/d. And the inflection point for daily sodium intake was 3634 mg/d in elderly population. The inflection point for daily potassium intake was 3501 mg/d. The inflection point for daily sodium-potassium ratio intake was 1.203 mg/mg/d, respectively, A healthy diet should be based on reasonable sodium intake and include an appropriate sodium-to-potassium ratio.

Intake and food sources of sodium in the population residing in urban areas of Ecuador: results from ELANS study

BACKGROUND

In 2021, WHO notes that globally, 32% of annual deaths worldwide are due to cardiovascular causes, which have been attributed to excessive sodium intake, and therefore recommends a reduction in salt intake to less than 5 g/day. Ecuador does not have data on sodium consumption in the population. Hence, this study sought to determine the association between sodium consumption and sociodemographic variables in subjects living in urban areas of Ecuador.

OBJECTIVES

Determine the main dietary sources of sodium in subjects living in urban areas of the Coast and Highlands of Ecuador, and the association between sodium intake and sociodemographic variables such as: sex, region, marital status, socio-economic and educational level of this population.

METHODS

Sodium intake was studied in 800 subjects of both sexes aged 15 to 65 years living in urban areas in Ecuador, originating from the Latin American Nutrition and Health Study (ELANS) between 2014 and 2015. Data were obtained through two 24-hour recalls, and were accessed according to sex, region, age, marital status, socio-economic and educational levels.

RESULTS

The mean sodium intake was 4900 mg/day (SD ± 1188.32 mg/day), and both sexes exceeded the recommendations. Adjusting for energy intake, sodium consumption is higher in participants aged 50-65 years, from low socio-economic status and with basic education level. A positive relationship was found between sodium and energy intake. Around 48% of the sodium sources included the spices, condiments and herbs group. Within this group, salt itself constitutes 99% of sodium sources.

CONCLUSIONS

The Ecuadorian population consumes more than double the sodium recommendations, which vary according to gender and age. The first source of sodium is salt itself, which is part of spices and condiments food group. This data is important to formulate public health policies and interventions in Ecuador, especially in the population at risk.

Validation of spot urine in estimating 24-h urinary sodium, potassium and sodium-to-potassium ratio during three different sodium diets in healthy adults

PURPOSE

To evaluate the validity of spot urine assay methods in estimating the 24-h urinary sodium, potassium and sodium-to-potassium ratio during three different sodium diets.

MATERIALS AND METHODS

Twelve healthy volunteers were asked to adhere to 3 dietary sodium targets (3.3-5.0g/day,<3.3 g/day and >5.0 g/day) for three consecutive weeks and to measure salt excretion daily in spot urine samples using a self-monitoring device. On day 7 of each week, 24-h urine was collected to compare measured with estimated 24-h salt excretion (by the Kawasaki, Tanaka and INTERSALT equations).

RESULTS

Correlation coefficients relating measured and estimated 24-h sodium excretion were low and not significant for Kawasaki and INTERSALT and moderate for the Tanaka equation (τ 0.56-0.64,p<.05). Bland-Altman plots showed considerable differences between estimated and measured sodium excretion across all salt diets. Over 40% of the participants showed an absolute difference between measured and estimated 24-h sodium of more than 1000 mg/day. The correlation coefficients between 24-h and spot Na/K ratio were 0.67, 0.94 and 0.85(p<.05), and mean differences were 0.59, 0.06 and 0.48 for the intermediate, low and high sodium diets, respectively.

CONCLUSION

These findings do not support estimation of individual 24-h salt excretion from spot urine by the Kawasaki, Tanaka, or INTERSALT formula. Plain language summaryAccurate monitoring of salt intake is essential to improve BP control. At present, measurement of sodium and potassium excretion in multiple non-consecutive 24-h urinary collections is considered the gold standard for measuring dietary sodium intake. However, this method is burdensome, time-consuming and error prone.Therefore, we assessed and compared the validity of three formula-based approaches to estimate 24-h urinary sodium and potassium excretion and the Na/K ratio from spot urine samples measured by a self-monitoring device under three different sodium diets using 24-h urine collections as the reference.We conclude that use of three commonly used equations that estimate 24-h urinary sodium and potassium excretion result in substantial bias, poor precision and poor accuracy and are therefore not recommended. The Na/K ratio based on multiple casual urine samples may be a useful, low-burden, low-cost alternative method to 24-h urine collection for monitoring daily salt intake.

Experience with 2 years' intervention to progressively reduce salt supply to kitchens in elderly care facilities-challenges and further research: post hoc analysis of the DECIDE-Salt randomized clinical trial

BACKGROUND

Progressive reduction of sodium intake is an attractive approach for addressing excessive salt intake, but evidence for this strategy in real practice is limited. We aimed to determine the feasibility, effectiveness, and safety of a progressive sodium intake reduction intervention in real-world setting.

METHODS

We randomized 48 residential elderly care facilities in China, with 1612 participants aged 55 years and older, to either progressive reduction (PR, 24 facilities) or no reduction (NR, 24 facilities) of the supply of study salt to the kitchens of these facilities for 2 years. The primary efficacy outcome was systolic blood pressure (SBP) at any scheduled follow-up visit. Secondary efficacy outcomes included diastolic blood pressure (DBP) at any scheduled follow-up visit, and major adverse cardiovascular events (comprising non-fatal stroke, non-fatal myocardial infarction, hospitalized non-fatal heart failure, or vascular death) and total mortality. The perception of food saltiness, the addition of out-of-study salt in meals, and 24-h urinary sodium excretion were used as process indicators.

RESULTS

Pre-specified analysis per randomization found no effect of the intervention on the 2-year overall mean systolic and diastolic blood pressure (SBP, DBP) and any other outcomes. However, post hoc analysis showed that the intervention effect on blood pressure varied over multiple follow-up visits (p for interaction < 0.046) and presented favorable differences at the 24-month visit (SBP =  - 3.0 mmHg, 95%CI =  - 5.6, - 0.5; p = 0.020; DBP =  - 2.0 mmHg, 95%CI - 3.4, - 0.63; p = 0.004). The effect on 24-h sodium was non-significant (- 8.4 mmol, 95%CI =  - 21.8 to 4.9, p = 0.216), though fewer participants with NR than with PR reported food tasting bland (odds ratio 0.46; 95%CI 0.29 to 0.73; p = 0.001). Reporting of bland food taste and other process measures indicated that intervention delivery and adherence were not fully achieved as designed.

CONCLUSIONS

The experience of this real-world study demonstrated that achieving acceptability and sustainability of the progressive sodium intake reduction strategy among older adults was challenging, but it has shown potential for effectiveness in these and potentially other residential settings if the lessons of DECIDE-Salt are applied in further studies.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03290716).

Blood pressure management and long-term outcomes in kidney transplantation: a holistic view over a 35-year period

INTRODUCTION

Hypertension is a burden for most kidney transplant recipients. Whether respect of hypertension guidelines results in better outcomes is unknown.

METHODS

In this multicenter study, office blood pressure at 12 months following transplantation (i.e., after > 20 outpatient visits), and survival were assessed over 35 years among 2004 consecutive kidney transplant recipients who received a first kidney graft from 1985 to 2019 (follow-up: 26,232 patient-years).

RESULTS

Antihypertensive medications were used in 1763/2004 (88.0%) patients. Renin-angiotensin-system blockers were used in 35.6% (47.1% when proteinuria was > 0.5 g/day) and calcium-channel blockers were used in 6.0% of patients. Combined treatment including renin-angiotensin-system-blockers, calcium-channel blockers and diuretics was used in 15.4% of patients receiving ≥ 3 antihypertensive drugs. Blood pressure was controlled in 8.3%, 18.8% and 43.1%, respectively, depending on definition (BP < 120/80, < 130/80, < 140/90 mmHg, respectively) and has not improved since the year 2001. Two-thirds of patients with uncontrolled blood pressure received < 3 antihypertensive classes. Low sodium intake < 2 g/day (vs ≥ 2) was not associated with better blood pressure control. Uncontrolled blood pressure was associated with lower patient survival (in multivariable analyses) and graft survival (in univariate analyses) vs controlled hypertension or normotension. Low sodium intake and major antihypertensive classes had no influence on patient and graft survival.

CONCLUSIONS

Pharmacological recommendations and sodium intake reduction are poorly respected, but even when respected, do not result in better blood pressure control, or patient or graft survival. Uncontrolled blood pressure, not the use of specific antihypertensive classes, is associated with reduced patient, and to a lesser extent, reduced graft survival, even using the 120/80 mmHg cut-off.

Results of Salt Intake Restriction Monitored with the New Sodium Control Biosensor

INTRODUCTION

Adherence to a low-sodium (Na) diet is crucial in patients under hemodialysis, as it improves cardiovascular outcomes and reduces thirst and interdialytic weight gain. Recommended salt intake is lower than 5 g/day. The new 6008 CAREsystem monitors incorporate a Na module that offers the advantage of estimating patients' salt intake. The objective of this study was to evaluate the effect of dietary Na restriction for 1 week, monitored with the Na biosensor.

METHODS

A prospective study was conducted in 48 patients who maintained their usual dialysis parameters and were dialyzed with a 6008 CAREsystem monitor with activation of the Na module. Total Na balance, pre-/post-dialysis weight, serum Na (sNa), changes in pre- to post-dialysis sNa (ΔsNa), diffusive balance, and systolic and diastolic blood pressure were compared twice, once after 1 week of patients' usual Na diet and again after another week with more restricted Na intake.

RESULTS

Restricted Na intake increased the percentage of patients on a low-Na diet (<85 Na mmol/day) from 8% to 44%. Average daily Na intake decreased from 149 ± 54 to 95 ± 49 mmol, and interdialytic weight gain was reduced by 460 ± 484 g per session. More restricted Na intake also decreased pre-dialysis sNa and increased both intradialytic diffusive balance and ΔsNa. In hypertensive patients, reducing daily Na by more than 3 g Na/day lowered their systolic blood pressure.

CONCLUSIONS

The new Na module allowed objective monitoring of Na intake, which in turn could permit more precise personalized dietary recommendations in patients under hemodialysis.

Case-based review of dietary management of cystinuria

PURPOSE

The currently recommended treatment strategy for cystine stone formers is based on a progressive approach that starts with the most conservative measures. In patients with cystinuria, increased patient compliance with dietary management and medical treatment is associated with fewer stone interventions. In this case-based review, the dietary management of cystine stone former was reviewed under the guidance of evidence-based medicine.

METHODS

The dietary management of the 13-year-old cystinuria patient, who underwent 18 endourological stone interventions, was reviewed in the light of evidence-based medicine. A literature search was performed in Pubmed, MEDLINE, Embase, and Cochrane Library databases according to PRISMA guidelines published from 1993 to September 2022. A total of 304 articles were included in this paper.

RESULTS

In managing patients with cystinuria, hyperhydration, and alkalinization of the urine with medical treatment, the rational use of cystine-binding drugs by taking into account individual situations has come to the fore. A limited study has argued that a vegetarian diet is effective as the alkaline load from fruits and vegetables can reduce the amount of alkalizing substances required to achieve urinary alkalinization above pH 7.5, making it particularly suitable for the dietary treatment of cystine stone disease.

CONCLUSION

Life-long follow-up with dietary modification, hyperhydration, and personalized medical therapy (alkalinization and cystine-binding drugs) are critical in preventing chronic kidney disease and kidney failure in cystinuria.

Dietary sodium intake remains high in Brazil: Data from the Brazilian National Dietary Surveys, 2008-2009 and 2017-2018

Reducing salt intake is considered one of the most cost-effective interventions to decrease morbidity and mortality resulting from noncommunicable diseases. This study aimed to describe changes in sodium intake in the Brazilian population using data from the National Dietary Surveys (NDS) conducted in 2008-2009 and 2017-2018. We hypothesized that over the 10-year period evaluated, sodium intake has remained high in Brazil. Nationwide representative samples of 34,003 and 46,164 individuals (aged ≥10 years) from NDS 2008-2009 and 2017-2018, respectively, were evaluated. Food consumption data were obtained from 2 nonconsecutive food records (NDS 2008-2009) and two 24-hour food recalls (NDS 2017-2018). Trends, percentiles of distribution, and proportions of the population exceeding the age-specific tolerable upper intake level for sodium were estimated. Dietary sodium intake was also estimated as a function of energy intake (mg/1000 kcal). Overall, mean crude daily sodium intake was slightly lower in 2017-2018 than in 2008-2009 (2489 mg/d vs. 2529 mg/d). The decrease in sodium intake (mg/day) was statistically significant (P < .05) only among female adolescents and subjects in the highest income level. Additionally, an overall statistically significant increase in dietary sodium density was observed independent of age, sex, and income level for energy-adjusted data (P < .05). Our findings indicate that sodium intake has not significantly changed over time in the Brazilian population; thus, policies aimed at reducing sodium intake in Brazil are necessary.

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.

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.

Sex-specific associations between potassium intake, blood pressure, and cardiovascular outcomes: the EPIC-Norfolk study

AIMS

A potassium replete diet is associated with lower blood pressure (BP) and lower risk of cardiovascular disease (CVD). Whether these associations differ between men and women and whether they depend on daily sodium intake is unknown.

METHODS AND RESULTS

An analysis was performed in 11 267 men and 13 696 women from the EPIC-Norfolk cohort. Twenty-four hour excretion of sodium and potassium, reflecting intake, was estimated from sodium and potassium concentration in spot urine samples using the Kawasaki formula. Linear and Cox regression were used to explore the association between potassium intake, systolic BP (SBP), and CVD events (defined as hospitalization or death due to CVD). After adjustment for confounders, interaction by sex was found for the association between potassium intake and SBP (P < 0.001). In women, but not in men, the inverse slope between potassium intake and SBP was steeper in those within the highest tertile of sodium intake compared with those within the lowest tertile of sodium intake (P < 0.001 for interaction by sodium intake). Both in men and women, higher potassium intake was associated with a lower risk of CVD events, but the hazard ratio (HR) associated with higher potassium intake was lower in women than in men [highest vs. lowest potassium intake tertile: men: HR 0.93, 95% confidence interval (CI) 0.87-1.00; women: HR 0.89, 95% CI 0.83-0.95, P = 0.033 for interaction by sex].

CONCLUSION

The association between potassium intake, SBP, and CVD events is sex specific. The data suggest that women with a high sodium intake in particular benefit most from a higher potassium intake with regard to SBP.

Thirst in stable heart failure patients; time to reconsider fluid restriction and prescribed diuretics

Aims

One of the bothersome symptoms that heart failure (HF) patients can experience is thirst. There are limited data on the association between thirst and fluid intake and clinical variables. Therefore, the aim of this study was to describe severe thirst in stable HF patients and assess factors related to severe thirst, including actual fluid intake and sodium intake.

Methods and results

The study had a cross‐sectional design. Stable HF patients from two HF clinics in the Netherlands were included and assessed thirst by a visual analogue scale ranging from 0 to 100. They also completed questionnaires on thirst distress, self‐care behaviour, and HF symptoms. A 3 day food diary was completed to assess actual fluid intake and sodium intake. Finally, patients collected urine for 24 h. Patients were divided into severe and low thirst based on thirst score and thirst distress. T‐tests, Mann–Whitney tests, and χ² tests were conducted to assess differences between both groups. Multivariable logistic regression analysis was performed to assess factors associated with severe thirst. A total of 100 patients were included (40% female, mean age 72 ± 12) of which 68 completed the food diary. The mean thirst score was 28 ± 25, and 25% experienced severe thirst. The majority of patients (94%) were prescribed a fluid restriction, 37% had a restriction between 1500 and 2000 mL, and 32% a restriction of 1500 mL. Severe thirst in the total group with 100 patients was associated with a higher dose of loop diuretics [odds ratio (OR) 3.25; 95% confidence interval (CI) 1.01–10.45; P = 0.048] and a higher urine output over 24 h (OR 1.002; 95% CI 1.00–1.003; P = 0.010). In the group of patients who completed the food diary (N = 68), severe thirst was associated with a higher sodium intake (OR 1.002; 95% CI 1.001–1.003; P = 0.003), a higher dose of loop diuretics (OR 22.69; 95% CI 2.78–185.04; P = 0.004), and more fatigue (OR 11.2; 95% CI 1.54–82.12; P = 0.017).

Conclusions

A quarter of all stable HF patients experienced severe thirst. A higher dose of loop diuretics was associated with more thirst; therefore, it might be important to review the dose of loop diuretics critically and try to decrease it in order to relieve severe thirst. Because all patients were prescribed a fluid restriction, a reconsideration of this restriction is also suggested.

Central interaction between nitric oxide, lactate and glial cells to modulate water and sodium intake in rats

The "astrocyte-to-neuron lactate shuttle" (ANLS) mechanism is part of the central inhibitory pathway to modulate sodium intake. An interaction between the GABAergic neurons and nitric oxide (NO) in the subfornical organ (SFO) in salt-appetite inhibition has been suggested. In addition, NO is a key molecule involved in astrocytic energy metabolism and lactate production. In the present study, we hypothesized there is an interaction between astrocytic lactate and central NO to negatively modulate water and sodium intake through the ANLS mechanism. The results showed that central Nω-nitro-L-arginine methyl ester (L-NAME, NO-synthase inhibition) induced an increase in water and sodium intake. These responses were attenuated by previous central microinjection of fluorocitrate (FCt, a reversible glial inhibitor). Interestingly, L-NAME-induced water and sodium intake were also decreased by previous microinjection of lactate but did not change after inhibition of the ANLS mechanism by α-cyano 4-hydroxycinnamic acid (α-CHCA), an inhibitor of the MCT lactate transporter. Our results suggest a central interaction between NO, glial cells, and lactate to modulate water and sodium intake.

High Estimated 24-Hour Urinary Sodium Excretion Is Related to Symptomatic Knee Osteoarthritis: A Nationwide Cross-Sectional Population-Based Study

OBJECTIVES

High salt intake results in various harmful effects on human health including hypertension, cardiovascular disease, and reduced bone density. Despite this, there are very few studies in the literature that have investigated the association between sodium intake and osteoarthritis (OA). Therefore, we aimed to explore these associations in a Korean population.

METHODS

This study used cross-sectional data from adult subjects aged 50-75 years from two consecutive periods of the Korean National Health and Nutrition Examination Survey V-VII (2010-2011 and 2014-2016). The estimated 24-hour urinary sodium excretion (24HUNa) was used as a surrogate marker of salt intake. In the 2010-2011 dataset, knee OA (KOA) was defined as the presence of the radiographic features of OA and knee pain. The association between KOA and salt intake was analysed using univariable and multivariable logistic regression methods. For the sensitivity analysis, the same procedures were conducted on subjects with self-reported OA (SR-OA) with knee pain in the 2010-2011 dataset and any site SR-OA in the 2014-2016 dataset.

RESULTS

Subjects with KOA had significantly lower energy intake, but higher 24HUNa than those without KOA. The restricted cubic spline plots demonstrated a J-shaped distribution between 24HUNa and prevalent KOA. When 24HUNa was stratified into five groups (<2, 2-3, 3-4, 4-5 and ≥5 g/day), subjects with high sodium intake (≥5 g/day) had a higher risk of KOA (odds ratio [OR] = 1.64, 95% confidence interval [CI] 1.03-2.62) compared to the reference group (3-4 g/day) after adjusting for covariates. The sensitivity analysis based on SR-OA with knee pain showed that high sodium intake was also significantly associated with increased prevalence of OA (OR = 1.84, 95% CI 1.10-3.10) compared with the reference group. Regarding SR-OA at any site in the 2014-2016 dataset, estimated 24HUNa showed a significantly positive association with the presence of SR-OA after adjusting for potential confounders.

CONCLUSIONS

This nationwide Korean representative study showed a significant association between symptomatic KOA and high sodium intake (≥5 g/day). Avoidance of a diet high in salt might be beneficial as a non-pharmacologic therapy for OA.

The role of body mass index in the association between dietary sodium intake and blood pressure: A mediation analysis with NHANES

BACKGROUND AND AIMS

Recent research demonstrated that obesity and high dietary sodium intake, the two established risk factors for hypertension, were associated with each other. The objective was to investigate the potential indirect effect of sodium intake on blood pressure via body mass index (BMI).

METHODS AND RESULTS

Using ten years data from US NHANES (2007-2016), the study included adult participants (>20 years old) who were not taking antihypertensive medications and without baseline diseases (n = 12,262). BMI was modelled as the mediator of sodium intake on systolic and diastolic blood pressure, adjusted for age, sex, socioeconomic status, smoking, drinking, physical activity, calorie intake, fluid intake and potassium intake. Mediation analysis was performed to evaluate total effect, direct effect and indirect effect via BMI. Subgroup analyses based on three age subgroups (20-40, 41-60 and ≥61 years old) were performed. The mean age was 39.29 (13.4) years and 53.1 (0.45) % were males. The mean BMI was 27.8 (6.20) kg/m². Overall, 1 g/d increase in sodium intake was associated with an increased systolic blood pressure by 0.36 (95% confidence interval 0.14 to 0.58) mmHg, with a direct effect (0.14 (0.09-0.19)) and an indirect effect via BMI (0.23 (0.02-0.44)). The indirect effect was mainly observed in participants ≤60 years old.

CONCLUSION

Sodium intake showed both direct effect and indirect effect (via BMI) on systolic blood pressure in US NHANES. The findings provide evidence for combining sodium restriction and weight reduction measures for prevention of hypertension. Cautions should be taken when generalizing the findings to other populations with lower average BMI.

Sodium found in processed cow milk and estimated intake by infants

OBJECTIVE

To determine the sodium concentration in cow milk available for sale and to estimate its consumption by infants up to 6 months of age.

METHODS

Sodium level was determined by flame emission spectrophotometry in eight different lots of five brands of liquid ultra-high temperature milk and three brands of powdered milk. To estimate sodium consumption via cow milk, orientations for exceptional situations when neither breastfeeding nor infant formula is possible were considered. Inferential statistics were performed and results were compared with critical parameters at a 5% significance level.

RESULTS

The mean sodium content per portion found in liquid milk (162.5±16.2) mg/200mL was higher than that in powdered milk (116.8±3.0) mg/26g. Estimated sodium consumption by infants through powdered milk varied from 149.8 to 224.7% of adequate intake, and via liquid milk can be more than 500% of the adequate intake, reaching 812.4% of it if dilution is not applied. Seven of the eight brands of milk studied had declared, on their labels, that the sodium content was 13-30% lower than that found in chemical analysis.

CONCLUSION

Liquid and powdered whole cow milk have high sodium content, and the content per portion is higher in liquid milk than in powdered milk. The estimated consumption of sodium through these products can far exceed the adequate intake for infants from 0 to 6 months old, even when the recommended dilution and maximum daily volumes are followed.

Rationale and validation of predicting high sodium intake by spot urinary chloride in patients with chronic kidney disease

OBJECTIVE

To analyze the rationale and evaluate the validity of spot urinary chloride or derived formulas to predict high sodium intake in patients with chronic kidney disease (CKD).

METHODS

We collected consecutive CKD patients at stages 1-4 who were admitted to our Nephrology department in a single center from January 01, 2014, to December 31, 2017, and tested spot and 24-hour urinary analysis on the same day. The feasibility of urinary chloride to predict urinary sodium was firstly analyzed by calculating their correlations. The validity of predicting excessive sodium intake by spot urinary sodium and chloride, two derived formulas based on spot urinary sodium or chloride, and our previous "CKDSALT" equation were accessed. We finally conducted Receiver operating characteristic (ROC) curves to compare their performance in detecting high sodium intake.

RESULTS

All 5204 patients were eventually analyzed. In the derivation cohort (n = 2447), a strong positive linear correlation existed between urinary sodium and chloride in both spot urine (R² = 0.804) and 24-hour urine samples (R² = 0.905), and two predictive equations based on spot urinary sodium or chloride were derived. In the validation cohort (n = 2757), spot urinary sodium and chloride only showed "fair" performance. However, both urinary sodium and chloride equations had a "good" performance in ICC, Pearson's correlation, Bland-Altman plots, and ROC curves, while and CKDSALT equation showed the best performance.

CONCLUSIONS

Spot urinary chloride is a feasible method to predict and monitor high sodium intake in CKD patients, while a novel derived formula could elevate its diagnostic accuracy.

Association between childhood obesity and familial salt intake: analysis of data from Korean National Health and Nutrition Examination Survey, 2014-2017

High salt intake is known as a risk factor of childhood obesity. As family members share not only genes but also their diet habit, parents' salt intake may affect to their children's obesity. In this study, we investigated correlations between childhood obesity and parents' or children's sodium intakes based on a nationwide survey data. From the Korean National Health and Nutrition Examination Survey data from 2014 to 2017, 802 boys and 657 girls aged 10-18 years, and their parents were included. BMI z-score and 24-hour urinary sodium excretion, which is estimated through Tanaka's equation, were used to examine associations between obesity and sodium intakes. The BMI status and the prevalence of obesity between children and their parents showed strong positive correlations in both sexes (all p < 0.001). The urinary sodium excretion between children and their parents showed positive correlations in both sexes (all p < 0.05). Children with higher urinary sodium excretion showed higher BMI (in both sexes, p < 0.001) and higher parental obesity compared to those with lower urinary sodium excretion, however, statistical significances of the latter relationship were varied by sex. In conclusion, our study suggests close relationship between childhood obesity and their sodium intakes, which also correlate well with parental BMIs and diet behavior. Therefore, parental education and active participation could be crucial in regulating childhood obesity.

Association between ultrapocessed food and chronic kidney disease

The modern diet is closely linked to the consumption of processed foods, causing an increase in the intake of salt, simple sugars, phosphorus and added potassium. This excess intake is associated with an increased risk of obesity, diabetes, hypertension and chronic kidney disease (CKD). CKD, which according to data from the ENRICA study affects 15% of the population, magnifies its impact due to the higher prevalence of diabetes and hypertension and due to limitations in the management of sodium and phosphorus. The intake of these products far exceeds the established recommendations, assuming 72% of total sodium, 25%-35% of phosphorus, 12%-18% of potassium and exceeding 10% of the caloric intake in simple sugars. Measures are necessary to reduce their contribution through nutritional advice, labeling review, education campaigns on healthy habits, fees and institutional actions that involve food safety agencies, industry, distribution and scientific societies.

Intake of processed meat, but not sodium, is associated with risk of colorectal cancer: Evidence from a large prospective cohort and two-sample Mendelian randomization

BACKGROUND & AIMS

Processed meat and high sodium intake are common in Western diet. The objective was to examine their independent effects on the risk of colorectal cancer (CRC).

METHODS

We performed both observational analysis with UK Biobank and genetic analysis with Mendelian randomization (MR). The 24-h urinary sodium (UNa) and reported intake of processed meat were fitted on incident CRC by multivariable Cox proportional hazard model, adjusted for covariates, such as age, gender, family history, etc. Different sodium measures were used for sensitivity analyses. Two-sample MR analyses were performed using summary data from genome-wide association studies of UNa and CRC. Multivariable MR was adjusted for body mass index.

RESULTS

We included 415 524 eligible participants from UK Biobank. During a median follow-up of 11.1 years, 2663 participants were diagnosed with CRC. High intake of processed meat independently increased risk of CRC by 23% (HR 1.23; 95% CI: 1.03 to 1.46), but 24-h UNa was not significantly associated with CRC (HR 0.96; 95% CI: 0.87 to 1.06). Furthermore, MR also showed little evidence for the effect of UNa on CRC (OR 1.02; 95% CI: 0.11 to 9.42). Sensitivity analyses showed consistent results across different measurements of sodium intake.

CONCLUSIONS

Intake of processed meat had an independent effect on the risk of CRC, but the risk was not associated with sodium level. Reduction of processed meat intake may be an effective strategy for CRC prevention, while sodium reduction should still be recommended to achieve other health benefits.

Sodium intake assessed by 24-h urine excretion and its relationship with anthropometric measurements in Malaysian adults

BACKGROUND

Sodium intake is associated with anthropometric measurement including weight, waist circumference (WC), and body mass index (BMI). Higher intake of sodium is usually linked to higher risk of obesity among adults globally, especially in developing countries. This study aims to explore the probable relationship between sodium intake by 24-h urine excretion assessment and anthropometric measurement of adults in Malaysia.

METHODS

A cross-sectional study was conducted from October 2017 to March 2018 using a multi-stage stratified sampling method among Malaysian adults aged 18 years old and above. Sodium intake was determined by 24-h urinary sodium excretion, estimated from the respondents' 24-h urinary sample. Height was obtained based on standard protocol. Weight and WC were measured twice using validated anthropometric equipment and BMI was calculated according to World Health Organization (WHO) 1998 classification. Descriptive analysis was done to describe socio-demographic characteristics. A simple linear regression and multiple linear regression tests were done to assess the relationship of 24-h urinary excretion and anthropometric measurement. All statistical analysis was done using SPSS version 22.0.

RESULTS

Of 1047 interviewed respondents, 798 respondents had done the 24-h urine collection (76.0% response rate). Majority was between 40 and 59 years old (43.5%) and married (77.7%). Simple linear regression showed a significant positive linear association between 24-h urinary excretion and household income, WC, and obese group. In the multivariate analysis, it was indicated that, an increase of 1 unit of BMI will significantly increase the sodium intake by 129.20 mg/dl and an increase of 1 cm of WC will significantly increase the sodium intake by 376.45 mg/dl.

CONCLUSION

Our study showed a positive significant relationship between sodium intake estimated by 24-h urinary sodium excretion and BMI of Malaysian adults. More research is suggested on how sodium control can potentially contribute to obesity prevention.

Risk factors related with high sodium intake among Malaysian adults: findings from the Malaysian Community Salt Survey (MyCoSS) 2017-2018

BACKGROUND

High sodium intake was an established risk factor for stroke and cardiovascular diseases. The objective of this study was to investigate factors associated with high sodium intake based on 24-h urinary sodium excretion from the MyCoSS study.

METHODS

The cross-sectional survey was conducted among adults aged 18 years and above in Malaysia. A multi-stage stratified sampling was used to represent nationally. Twenty-four-hour urine was collected from a total of 900 respondents. Indirect ion-selective electrode (ISE) method was used to measure sodium intake. Descriptive and logistic regression analysis was applied to determine factors associated with high sodium intake based on 24-h urinary sodium excretion.

RESULTS

A total of 798 respondents (76% response rate) completed the 24-h urine collection process. Logistic regression revealed that high sodium intake associated with obese [aOR 2.611 (95% CI 1.519, 4.488)], male [aOR 2.436 (95% CI 1.473, 4.030)], having a waist circumference of > 90cm for adult males [aOR 2.260 ( 95% CI 1.020, 5.009) and >80cm for adult females [aOR 1.210 (95% CI 0.556, 2.631)], being a young adult [aOR 1.977 (95% CI 1.094, 3.574)], and living in urban areas [aOR 1.701 (95% CI 1.094, 2.645)].

CONCLUSION

Adults who are obese, have a large waist circumference, of male gender, living in urban areas, and belonging to the young adult age group were found to have higher sodium intake than other demographic groups. Hence, reduction of salt consumption among these high-risk groups should be emphasised to reduce the risk of cardiovascular diseases.

Knowledge, perception, and practice related to sodium intake among Malaysian adults: findings from the Malaysian Community Salt Study (MyCoSS)

BACKGROUND

Excessive intake of sodium is a major public health concern. Information on knowledge, perception, and practice (KPP) related to sodium intake in Malaysia is important for the development of an effective salt reduction strategy. This study aimed to investigate the KPP related to sodium intake among Malaysian adults and to determine associations between KPP and dietary sodium intake.

METHODS

Data were obtained from Malaysian Community Salt Survey (MyCoSS) which is a nationally representative survey with proportionate stratified cluster sampling design. A pre-tested face-to-face questionnaire was used to collect information on socio-demographic background, and questions from the World Health Organization/Pan American Health Organization were adapted to assess the KPP related to sodium intake. Dietary sodium intake was determined using single 24-h urinary sodium excretion. Respondents were categorized into two categories: normal dietary sodium intake (< 2000 mg) and excessive dietary sodium intake (≥ 2000 mg). Out of 1440 respondents that were selected to participate, 1047 respondents completed the questionnaire and 798 of them provided valid urine samples. Factors associated with excessive dietary sodium intake were analyzed using complex sample logistic regression analysis.

RESULTS

Majority of the respondents knew that excessive sodium intake could cause health problems (86.2%) and more than half of them (61.8%) perceived that they consume just the right amount of sodium. Overall, complex sample logistic regression analysis revealed that excessive dietary sodium intake was not significantly associated with KPP related to sodium intake among respondents (P > 0.05).

CONCLUSION

The absence of significant associations between KPP and excessive dietary sodium intake suggests that salt reduction strategies should focus on sodium reduction education includes measuring actual dietary sodium intake and educating the public about the source of sodium. In addition, the relationship between the authority and food industry in food reformulation needs to be strengthened for effective dietary sodium reduction in Malaysia.

Association between ultrapocessed food and chronic kidney disease

The modern diet is closely linked to the consumption of processed foods, causing an increase in the intake of salt, simple sugars, phosphorus and added potassium. This excess intake is associated with an increased risk of obesity, diabetes, hypertension and chronic kidney disease (CKD). CKD, which according to data from the ENRICA study affects 15% of the population, magnifies its impact due to the higher prevalence of diabetes and hypertension and due to limitations in the management of sodium and phosphorus. The intake of these products far exceeds the established recommendations, assuming 72% of total sodium, 25-35% of phosphorus, 12-18% of potassium and exceeding 10% of the caloric intake in simple sugars. Measures are necessary to reduce their contribution through nutritional advice, labeling review, education campaigns on healthy habits, fees and institutional actions that involve food safety agencies, industry, distribution and scientific societies.

Locked on salt? Excessive consumption of high-sodium foods during COVID-19 presents an underappreciated public health risk: a review

Abrupt changes in food preferences and eating habits have induced an overlooked health risk during the coronavirus disease pandemic (COVID-19). Indeed, emerging evidence points to a major shift to consumption of high-sodium foods during the pandemic lockdowns in the population from different countries and cultures. High-sodium foods have sodium contents exceeding 500 mg per 100 g, and many processed and preserved foods fall into this category. Excessive dietary sodium intake is associated with chronic diseases including hypertension, cardiovascular diseases, and kidney diseases, and thus poses confounding risks during the pandemic. Here, we review food categories in consumers' shopping lists and food parcels delivered to people who needed assistance during the pandemic, when frozen meals, canned foods, instant foods, snacks, and other high-sodium foods gained substantial popularity. Such change in consumers' behavior is driven by several factors: the perceived risk of viral infection in grocery shopping trips, limited supplies and inflated prices of fresh produce, preference on foods with long shelf lives, and emotional eating. Moreover, the general low awareness of sodium contents in food has contributed to the increased consumption of high-sodium foods during the pandemic. We also discuss the possible effects on COVID-19 infection and severity caused by excessive sodium intake. We conclude that the public should be educated to maintain a healthy sodium intake during the pandemic, and measures should be adopted by governments and private donors in procuring food parcels with more balanced sodium contents to lower the risks of prolonged and excessive sodium intakes in the vulnerable population.

Trends of stroke attributable to high sodium intake at the global, regional, and national levels from 1990 to 2019: a population-based study

Objectives: High sodium intake is associated with a higher risk of stroke. However, global patterns and trends in the stroke burden attributable to high sodium intake have not been systematically assessed.Methods: We used the numbers and age-standardized mortality rate (ASMR), and disability-adjusted life years (DALYs) rate (ASDR) of the stroke burden attributable to high sodium intake by sex, socio-demographic index (SDI), and country, obtained from the Global Burden of Disease Study (GBD) 2019. We calculated the estimated annual percentage changes (EAPCs) to assess the trends of ASMR and ASDR of the disease burden attributable to high sodium intake between 1990 and 2019. We further calculated the contribution of changes in population growth, population aging, and mortality or DALYs to changes in total stroke deaths and DALYs.Results: From 1990 to 2019, the global burden of stroke attributable to high sodium intake changed significantly, from a universal burden in Asia and Europe to one that mainly affected some countries in Asia and Oceania. This change was due to the combined effects of demographic changes and changes in mortality or DALY rates. For countries in Asia and Oceania, the effects of population aging and population growth outweighed the effects of declining mortality and DALY rates, resulting in an absolute increase in strokes attributable to high sodium intake.Conclusion: Although the age-standardized global stroke burden attributable to high sodium intake has declined from 1990 to 2019, the burdens in some Asia and Oceania countries, particularly China, remain high.

The association between dietary sodium intake, adiposity and sugar-sweetened beverages in children and adults: a systematic review and meta-analysis

Higher intakes of Na may contribute to weight gain. The primary aim of this systematic review and meta-analysis was to examine the relationship between dietary Na intake and measures of adiposity in children and adults. Given the previous link between Na intake and the consumption of sugar-sweetened beverages (SSB), which are a known risk factor for obesity, a secondary aim examining the relationship between Na intake and SSB consumption was assessed. A systematic literature search identified cross-sectional and longitudinal studies and randomised controlled trials (RCT) which reduced dietary Na (≥3 months). Meta-analysis was performed for outcomes with ≥3 studies. Cross-sectionally higher Na intakes were associated with overweight/obesity in adults (five studies; n 11 067; OR 1·74; 95 % CI 1·43, 2·13) and in children (three studies; n 3625, OR 3·29; 95 % CI 2·25, 4·80), and abdominal obesity (five studies; n 19 744; OR 2·04; 95 % CI 1·72, 2·42) in adults. Overall, associations remained in sensitivity analyses which adjusted for energy. Findings from longitudinal studies were inconsistent. RCT in adults indicated a trend for lower body weight on reduced-Na compared with control diets (fifteen studies; n 5274; -0·29 kg; 95 % CI -0·59, 0·01; P = 0·06); however, it is unclear if energy intakes were also altered on reduced-Na diets. Among children higher Na intakes were associated with higher intake of SSB (four studies, n 10 329, b = 22, 16 and 26 g/d); no studies were retrieved for adults. Overall, there was a lack of high-quality studies retrieved. While cross-sectional evidence indicates Na intake was positively associated with adiposity, these findings have not been clearly confirmed by longitudinal studies or RCT.

Genetically, Dietary Sodium Intake Is Causally Associated with Salt-Sensitive Hypertension Risk in a Community-Based Cohort Study: a Mendelian Randomization Approach

PURPOSE OF REVIEW

Excessive dietary salt intake is associated with an increased risk of hypertension. Salt sensitivity, i.e., an elevation in blood pressure in response to high dietary salt intake, has been associated with a high risk of cardiovascular disease and mortality. We investigated whether a causal association exists between dietary sodium intake and hypertension risk using Mendelian randomization (MR).

RECENT FINDINGS

We performed an MR study using data from a large genome-wide association study comprising 15,034 Korean adults in a community-based cohort study. A total of 1282 candidate single nucleotide polymorphisms associated with dietary sodium intake, such as rs2960306, rs4343, and rs1937671, were selected as instrumental variables. The inverse variance weighted method was used to assess the evidence for causality. Higher dietary sodium intake was associated with salt-sensitive hypertension risk. The variants of SLC8E1 rs2241543 and ADD1 rs16843589 were strongly associated with increased blood pressure. In the logistic regression model, after adjusting for age, gender, smoking, drinking, exercise, and body mass index, the GRK4 rs2960306TT genotype was inversely associated with hypertension risk (OR, 0.356; 95% CI, 0.236-0.476). However, the 2350GG genotype (ACE rs4343) exhibited a 2.11-fold increased hypertension risk (OR, 2.114; 95% CI, 2.004-2.224) relative to carriers of the 2350AA genotype, after adjusting for confounders. MR analysis revealed that the odds ratio for hypertension per 1 mg/day increment of dietary sodium intake was 2.24 in participants with the PRKG1 rs12414562 AA genotype. Our findings suggest that dietary sodium intake may be causally associated with hypertension risk.

Contribution of major food companies and their products to household dietary sodium purchases in Australia

Background

The Australian federal government will soon release voluntary sodium reduction targets for 30 packaged food categories through the Healthy Food Partnership. Previous assessments of voluntary targets show variable industry engagement, and little is known about the extent that major food companies and their products contribute to dietary sodium purchases among Australian households.

Methods

The aim of this cross-sectional study was to identify the relative contribution that food companies and their products made to Australian household sodium purchases in 2018, and to examine differences in sodium purchases by household income level. We used 1 year of grocery purchase data from a nationally representative consumer panel of Australian households who reported their grocery purchases (the Nielsen Homescan panel), combined with database that contains product-specific sodium content for packaged foods and beverages (FoodSwitch). The top food companies and food categories were ranked according to their contribution to household sodium purchases. Differences in per capita sodium purchases by income levels were assessed by 1-factor ANOVA. All analyses were modelled to the Australian population in 2018 using sample weights.

Results

Sodium data were available from 7188 households who purchased 26,728 unique products and purchased just under 7.5 million food product units. Out of 1329 food companies, the top 10 accounted for 35% of unique products and contributed to 58% of all sodium purchased from packaged foods and beverages. The top three companies were grocery food retailers each contributing 12–15% of sodium purchases from sales of their private label products, particularly processed meat, cheese and bread. Out of the 67 food categories, the top 10 accounted for 73% of sodium purchased, particularly driven by purchases of processed meat (14%), bread (12%) and sauces (11%). Low-income Australian households purchased significantly more sodium from packaged products than high-income households per capita (452 mg/d, 95%CI: 363-540 mg/d, P < 0.001).

Conclusions

A small number of food companies and food categories account for most of the dietary sodium purchased by Australian households. Prioritizing government engagement with these groups could deliver a large reduction in population sodium intake.

Sodium Intake, Blood Pressure and Cardiovascular Disease

Sodium intake reduction has been emphasized because sodium adversely impacts health, especially blood pressure (BP), and the cardiovascular (CV) disease risk. However, data obtained from several cohort studies have raised questions regarding the effects of high sodium intake on BP and the CV disease risk. In the present study, we systematically reviewed the literature to evaluate these associations. Studies showing negative associations between urine sodium and BP and CV outcomes relied on estimated 24-hour urine sodium from spot urine that is inappropriate for determining sodium intake at an individual level. Furthermore, controversy about the association between 24-hour urine sodium and BP may have been caused by different characteristics of study populations, such as age distribution, ethnicity, potassium intake and the inclusion of patients with hypertension, the different statistical methods and BP measurement methods. Regarding the association between sodium intake and the CV disease risk, studies showing negative or J- or U-shaped associations used a single baseline measurement of 24-hour urine sodium in their analyses. However, recent studies that employed average of subsequently measured 24-hour urine sodium showed positive, linear associations between sodium intake and CV outcomes, indicating that controversies are caused by the different sodium intake measurement methods and analytic designs. In conclusion, the study shows that positive associations exist between sodium intake and BP, CV outcomes, and mortality, and that the argument that reducing sodium intake is dangerous is invalid. Sodium intake reduction should be recommended to all, and not limited to patients with hypertension or CV disease.

Dietary Intake of Sodium during Infancy and the Cardiovascular Consequences Later in Life: A Scoping Review

BACKGROUND

High sodium intake is a leading cause of cardiovascular diseases in adults. Further, there is evidence that events in early life are predictors for health outcomes in later life. However, little is known about the impact of early sodium intake on (cardiovascular) health outcomes in later life.

SUMMARY

We performed a scoping review of 25 articles, including 11 review studies, 8 randomized controlled trials, 5 prospective cohort studies, and 1 retrospective cohort study, all describing the relationship between the amount of sodium intake during the first 6 months after birth and the health effects and/or risk to cardiovascular disease later in life. We divided the results into 2 different groups: human and animal studies. Key Messages: The results show that high sodium intake in the first 6 months after birth may lead to negative health effects such as higher blood pressure, due to factors like salty taste preference and alterations of the renal system. The findings of this study suggest that the amount of sodium in the diet of an infant in the first 6 months after birth may have an impact on cardiovascular health outcomes in later life.

Salt, No Salt, or Less Salt for Patients With Heart Failure?

Restricting dietary sodium is a common recommendation given by clinicians to patients with heart failure and is one supported by current guidelines. However, the quality of evidence for this recommendation is suboptimal, and there is no consensus on the optimal level of sodium intake. Though excessive sodium intake is associated with left ventricular hypertrophy and hypertension, recent data have suggested that very low sodium intake is paradoxically associated with worse outcomes for patients with heart failure. This is possibly explained by the association between low sodium intake and activation of the sympathetic and renin-angiotensin-aldosterone systems. Nevertheless, sodium restriction is routinely recommended and remains a cornerstone of heart failure and blood pressure therapy. In this review we discuss the pros and cons of sodium restriction for patients with heart failure from the current literature.

Boer goats physiology adaptation to saline drinking water

To examine the adaptive physiological responses to increasing salinity of drinking water in a choice situation, twelve female non-lactating Boer goats were used. After a control period with fresh water, in phase 2 the choice between different salt concentrations (0.25, 0.5, 0.75, 1.0, 1.25 and 1.5% NaCl) and tap water was offered for two weeks. Subsequently, goats were stepwise habituated to saline water by only offering the choice between salted water with different increasing concentrations (up to 1.5% NaCl) for four weeks. In phase 4 the procedure of phase 2 was repeated. BW was not affected by saline water intake, whereas BCS decreased. Total water intakes differed between ages (P < .001), and increased (P < .001) from 91.6 to 118.0 g/kg BW^0.82/day and from 105.5 to 142.9 g/kg BW^0.82/day in young and old goats in phase 3, respectively. In adult goats, rumen temperature decreased (P < .05) with prolonged saline water intake, while it remained unaffected in young goats. Increasing consumption of saline water decreased plasma concentrations of magnesium (from 0.95 to a minimum of 0.80 mmol/L in phase 3, P < .001). Creatinine increased from 82.92 to 93.39 μmol/L in the post-trial period 4 (P < .02) and potassium concentration increased from phase 2 (P < .001). ALT, AST, glucose, urea, calcium, sodium, osmolality were unaffected. All measured blood parameters remained within reference ranges, indicating that the stepwise adaptation to saline drinking water applying concentrations up to 1.5% across 4 weeks caused no harmful effects. Young animals were less resistant to salt toxicity compared to older ones.

Salt has contrasting effects on the digestive processing of dilute nectar by two Neotropical nectarivorous bats

Nectarivorous vertebrates might include sugar-dilute nectar in their diet and they are expected to undergo compensatory feeding. However, physiological constraints might limit the intake of sugar-dilute nectar, affecting energy budgets. Among other physiological processes, the limiting role of osmoregulation is supported by enhanced intake rate of dilute sugar solutions by avian nectarivores when salt is added. We tested if the Greater Antillean Long-tongued bat (Monophyllus redmani) and the Brown flower bat (Erophylla sezekorni) compensated energy intake when fed dilute-sugar solutions (2.5 and 5% sucrose), and if salt content (11, 20 and 40 mM NaCl l^-1) modulated the intake rate of these solutions. Both species were unable to compensate intake of solutions with varying sugar densities, and energy intake on the 2.5 and 5% diets was lower than on the most concentrated diets (10, 20 and 30% sucrose). Both species responded differently to the addition of salt. Salt addition did not affect the intake of 2.5% sugar solutions by the Greater Antillean Long-tongued bat, and it decreased the intake of 5% sugar solutions. In contrast, the Brown flower bat increased the intake of 2.5 and 5% sugar solutions when salt was added. Intake responses to varying sugar densities of our two focal species and that of other bat species previously studied indicate that they are not uniform and that they might be modulated by digestive and osmoregulatory physiological traits.

Simulating the impact of sodium reduction from packaged foods on population sodium intake in US adults and children

OBJECTIVE

To simulate the impact that Na reductions in food categories that are the largest contributors to dietary Na intake would have on population Na intake from packaged foods among US adults and children.

DESIGN

24 h Dietary recall data were used. For each store-bought packaged food product reported by participants, we generated sales-weighted Na content at the median and 25th percentile using Nutrition Facts Panel data from 193 195 products purchased by US households. The impact that Na reductions would have on population Na intake, overall and by sociodemographic subgroup, was examined.

SETTINGS

US households.

PARTICIPANTS

Children aged 2-18 years (n 2948) and adults aged >18 years (n 4878), 2011-2012 National Health and Nutrition Examination Survey.

RESULTS

Na intake from packaged foods was 1258 (se 21) mg for adults and 1215 (se 35) mg for children. Top-ten packaged food group sources contributed 67 % of Na intake. For adults and children, there was a decrease of 8·7 % (109 mg) and 8·0 % (97 mg), respectively, in Na intake if the top-ten sources reduced Na from the median to the 25th percentile. Although absolute reduction in intake varied between sociodemographic subgroups, significant differences were not observed.

CONCLUSIONS

The study demonstrated that if Na reduction shifted the top-ten packaged food group sources of dietary Na intake from the median to 25th percentile, population Na intake would be reduced by 9 % in US adults and children. These findings will help inform the US government's Na reduction targets, as well as policy makers' understanding of differences in intake of critical sub-populations in the USA.

Development and Validation of Equations to Estimate 24-H Urinary Sodium Excretion from Urine Samples of Patients with Chronic Kidney Disease

INTRODUCTION

The assessment of sodium intake is difficult due to low accuracy of dietary records and to the inconvenience of 24-h urine collections. Therefore, equations based on spot urine samples have been proposed to estimate sodium intake. In this study, we aimed to develop and to validate equations to estimate 24-h urinary sodium excretion (24hUNa) from several urine samples in chronic kidney disease (CKD) patients.

METHODS

Cross-sectional study with 76 CKD patients (males 55.3%; age: 64.5 [56.0-69.0] years; glomerular filtration rate 27.8 [24.7-32.1] mL/min). Sodium excretion was measured in 12-h daytime and 12-h nighttime collections; spot 1 (first urine of the day) and spot 2 (second urine of the day). By multivariable linear regression analysis, 4 equations were developed. The equations' accuracy was evaluated by P30 test. Association between estimated and measured 24hUNa was assessed by intraclass correlation coefficient (ICC); mean differences and limits of agreement by Bland-Altman plot. Data from 51 CKD patients of other CKD outpatient clinic were used to validate the equation developed from spot 2.

RESULTS

The 4 equations showed significant (p < 0.001) ICC and relatively good accuracy when compared to 24hUNa (Daytime: ICC = 0.89; P30 = 84%; Nighttime: ICC = 0.90; P30 = 83%; spot 1: ICC = 0.85; P30 = 78%; and spot 2: ICC = 0.70; P30 = 76%). In validation set, the equation from spot 2 was moderately accurate (P30 = 67%). Mean bias and ICC were 19.9 mmol/day and 0.58 (p = 0.001), respectively. A high sensitivity (97%) and specificity (89%) were found for a cutoff of 3.6 g of sodium/day.

CONCLUSION

Equations derived from 12 h collections better performed than spot urine when compared to gold standard 24hUNa. The equation from spot 2 showed good sensitivity to identify excessive sodium intake.

Effectiveness of Changes in Diet Composition on Reducing the Incidence of Cardiovascular Disease

PURPOSE OF REVIEW

To highlight dietary changes shown to be associated with a lower risk of cardiovascular events in epidemiological studies and that have been proven to be effective in preventing cardiovascular diseases in clinical trials RECENT FINDINGS: Since dietary changes always involve multiple variables, recent observational and intervention studies on dietary prevention of cardiovascular disease focus not only to the limitation of a single nutrient/food intake but also to the other dietary changes implemented to replace it. The available evidence supports three major dietary strategies for cardiovascular disease prevention: (1) the replacement of saturated fat with unsaturated fat and/or fiber-rich carbohydrate foods; (2) the reduction of salt intake; (3) the implementation of dietary patterns resembling the traditional Mediterranean diet. This support derives not only from RCTs but also from the combination of large observational cohort studies and relatively short-term randomized trials on cardiovascular risk factors.

GLP-1 receptor agonists do not affect sodium intake: Exploratory analyses from two randomized clinical trials

OBJECTIVES

Excessive sodium intake, despite current dietary advice, remains a global issue with cardiovascular and renal consequences. The aim of this study was to determine whether glucagon-like peptide receptor agonists (GLP-1 RAs), used as antihyperglycemic agents for type 2 diabetes (T2DM) management, may reduce salt cravings as they are known to reduce hedonic feeding behavior and are involved in sodium homeostasis by increasing renal sodium excretion.

METHODS

We performed exploratory analyses using data from two randomized, clinical crossover trials, which primarily aimed to assess the effects of GLP-1 RAs on central satiety and reward circuits and subsequent related feeding behavior. In study A, healthy, obese individuals and patients with T2DM were randomly assigned to receive intravenous administration of placebo or GLP-1 RA exenatide with or without concurrent GLP-1 receptor blockade, on separate testing days. In study B, individuals with T2DM randomly received GLP-1 RA liraglutide (titrated up to 1.8 mg daily) or titrated insulin glargine for 12 wk. In both studies, participants received an ad libitum mixed meal that served to calculate sodium intake. Moreover, salt craving was scored using a Likert scale.

RESULTS

In study A, acute exenatide, parallel to reduced total food intake, reduced sodium intake in all studied groups by up to 30%. In study B, prolonged liraglutide treatment did not affect sodium or total caloric intake. Neither acute exenatide nor prolonged liraglutide treatment affected salt craving as measured by the Likert scale.

CONCLUSION

Acute exenatide reduced sodium intake in light of a generalized reduction in food ingestion, while prolonged intervention with liraglutide did not lower sodium intake. Neither intervention affected salt craving. Given the known effects of these drugs on renal sodium excretion, blood pressure, and renal and cardiovascular outcome, it seems plausible to perform dedicated mechanistic studies in humans to assess the effects of GLP-1 RA administration on sodium balance.

High Sodium Intake Impairs Small Artery Vasoreactivity in vivo in Dahl Salt-Sensitive Rats

The effects of high sodium intake on the functionality of resistance arteries have been repeatedly studied in vitro, but no study has focused on salt-sensitive hypertension in vivo. We studied the in vivo reactivity of mesenteric small arteries (MSAs) to vasoactive agents in Dahl salt-sensitive (DS) rats with various sodium diets. Twenty-four male DS rats were randomized into 3 groups: LS (0.3% NaCl diet), NS (0.6% NaCl diet), and HS (8% NaCl diet). After a 12-week intervention, the diameter changes of the MSAs after noradrenaline (NA) and acetylcholine (ACh) exposure were detected by a microscope, and changes in blood perfusion through the MSAs were measured by full-field laser perfusion imaging. HS enhanced the constrictive response of the MSAs to NA and attenuated the relaxing response to ACh. Low sodium intake reduced the response of the MSAs to NA and promoted ACh-induced vasodilatation. HS also aggravated NA-induced blood perfusion reduction and impaired ACh-induced hyperperfusion of the MSAs. Pathologically, HS was associated with arteriolar structural damage and fibrosis of the MSAs. We conclude that sodium intake affects the responsiveness of the MSAs to vasoactive agents in DS rats and might play important roles in modulating blood pressure in hypertensive individuals.

The impact of food reformulation on nutrient intakes and health, a systematic review of modelling studies

BACKGROUND

Unhealthy diet is a risk factor for adverse health outcomes. Reformulation of processed foods has the potential to improve population diet, but evidence of its impact is limited. The purpose of this review was to explore the impact of reformulation on nutrient intakes, health outcomes and quality of life; and to evaluate the quality of modelling studies on reformulation interventions.

METHODS

A systematic review of peer-reviewed articles published between January 2000 and December 2017 was performed using MEDLINE, ScienceDirect, Embase, Scopus, Cochrane, and the Centre for Reviews and Dissemination of the University of York. Additional studies were identified through informal searches on Google and specialized websites. Only simulation studies modelling the impact of food reformulation on nutrient intakes and health outcomes were included. Included articles were independently extracted by 2 reviewers using a standardized, pre-piloted data form, including a self-developed tool to assess study quality.

RESULTS

A total of 33 studies met the selected inclusion criteria, with 20, 5 and 3 studies addressing sodium, sugar and fats reformulation respectively, and 5 studies addressing multiple nutrients. Evidence on the positive effects of reformulation on consumption and health was stronger for sodium interventions, less conclusive for sugar and fats. Study features were highly heterogeneous including differences in methods, the type of policy implemented, the extent of the reformulation, and the spectrum of targeted foods and nutrients. Nonetheless, partial between-study comparisons show a consistent relationship between percentages reformulated and reductions in individual consumption. Positive results are also shown for health outcomes and quality of life measures, although comparisons across studies are limited by the heterogeneity in model features and reporting. Study quality was often compromised by short time-horizons, disregard of uncertainty and time dependencies, and lack of model validation.

CONCLUSIONS

Reformulation models highlight relevant improvements in diets and population health. While models are valuable tools to evaluate reformulation interventions, comparisons are limited by non-homogeneous designs and assumptions. The use of validated models and extensive scenario analyses would improve models' credibility, providing useful insights for policy-makers.

REVIEW REGISTRATION

A research protocol was registered within the PROSPERO database (ID number CRD42017057341).

Association of sodium intake and major cardiovascular outcomes: a dose-response meta-analysis of prospective cohort studies

Background

The association of sodium intake with the risk of cardiovascular morbidity and mortality is inconsistent. Thus, the present meta-analysis was conducted to summarize the strength of association between sodium intake and cardiovascular morbidity and mortality.

Methods

PubMed, Embase, and the Cochrane Library were searched systematically to identify the relevant studies up to October 2017. The effect estimates for 100 mmol/day increase in sodium intake were calculated using 95% confidence intervals (CIs) of cardiac death, total mortality, stroke, or stroke mortality for low (< 3 g/d), moderate (3–5 g/d), or heavy (> 5 g/d) sodium intake, and minimal sodium intake comparison.

Results

A total of 16 prospective cohort studies reported data on 205,575 individuals. The results suggested that an increase in sodium intake by 100 mmol/d demonstrated little or no effect on the risk of cardiac death (P = 0.718) and total mortality (P = 0.720). However, the risk of stroke incidence (P = 0.029) and stroke mortality (P = 0.007) was increased significantly by 100 mmol/day increment of sodium intake. Furthermore, low sodium intake was associated with an increased risk of cardiac death (P = 0.003), while moderate (P < 0.001) or heavy (P = 0.001) sodium intake was associated with an increased risk of stroke mortality.

Conclusions

These findings suggested that sodium intake by 100 mmol/d increment was associated with an increased risk of stroke incidence and stroke mortality. Furthermore, low sodium intake was related to an increased cardiac death risk, while moderate or heavy sodium intake was related to an increased risk of stroke mortality.

The purinergic mechanism of the central nucleus of amygdala is involved in the modulation of salt intake in sodium-depleted rats

The central nucleus of the amygdala (CeA) is a critical region in regulating sodium intake, and interestingly, purinergic receptors reportedly related to fluid balance, are also expressed in CeA. In this study, we investigated whether the purinergic mechanisms of CeA were involved in regulating sodium intake. Male Sprague-Dawley rats had cannulas implanted bilaterally into the CeA and were sodium depleted with furosemide (FURO 20 mg/kg) plus 24 h-sodium deficient food fed. Bilateral injections of the P2X purinergic agonist, α,β-methyleneadenosine 5'-triphosphate (α,β-methylene ATP 1.0, 2.0, 4.0 nmol, respectively) into the CeA region induced dose-related reductions in sodium intake without affecting water intake. Injection of P2X purinergic antagonist, pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS 4.0 nmol/0.5 μl) into the CeA region did not alter sodium and water intake, however, prior injection of PPADS into the CeA area abolished the inhibitory effects on sodium intake by α,β-methylene ATP. Interestingly, prior injection of γ-aminobutyric acid type A (GABA_A) receptor antagonist, bicuculline (4.0 nmol/0.5 μl) into the CeA region partially reversed the deficit of sodium intake induced by α,β-methylene ATP. These results suggest that purinergic receptors in the CeA are involved in the control of sodium intake in the sodium-depleted rats and this negative modulation may be, at least partly, mediated by the GABA_A receptor.

Cooking parameters affect the sodium content of prepared pasta

The quantitative effect of different preparation variables on the sodium content of cooked dry pasta was evaluated. Semolina spaghetti (<5 mg sodium/100 g) was cooked by a typical method (454 g, 5.68 L water, 36 g salt, al dente, no rinsing) and after systematic variation of amount of salt, water:pasta ratio, cooking volume and time, rinsing, pasta shape, whole grain. Sodium was assayed by ICP-MS, including rigorous quality control. Pasta cooked without salt had <5 mg sodium/140 g serving, and 247-490 mg/serving when cooked in salted water by the different variations. Rinsing reduced sodium by 34%. There was a linear relationship between salt concentration in cooking water and sodium in cooked pasta; doubling the concentration increased sodium by 243 mg/serving (>10% of 2300 mg/day), relative to the reference method. No other variables affected sodium. Results allow more accurate estimation of sodium intake from cooked pasta, since food composition tables that do not reflect variations in cooking parameters.

Factors Predicting Sodium Intake of Korean Americans with Type 2 Diabetes

The increasing prevalence of type 2 diabetes mellitus (T2DM) and its complications including cardiovascular disease and chronic kidney disease threaten Korean Americans (KAs). High dietary sodium intake contributes to both conditions. The purpose of the study was to assess dietary sodium consumption and to examine the predictors of sodium intake among KA with T2DM. A total 232 KA who had uncontrolled diabetes participated in this study. The majority of the sample (69%) consumed more sodium than current national guidelines. A high level of energy intake was the strongest predictor for sodium intake with gender and marital status also related. Our findings identified predictive factors to excessive sodium intake and these data support the need for culturally-tailored education about appropriate dietary sodium and energy intake are needed for patients about T2DM.

High sodium intake and sodium to potassium ratio may be linked to subsequent increase in vascular damage in adults aged 40 years and older: the Korean multi-rural communities cohort (MRCohort)

PURPOSE

Subclinical vascular damage is a chronic intermediate process in cardiovascular disease (CVD) and high sodium (Na) has been regarded as an adverse factor in subclinical vascular health; however, the longitudinal relationship between Na intake and subclinical vascular damage has not been studied. We aimed to evaluate the longitudinal relationship of dietary Na intake and sodium to potassium ratio (Na:K) with brachial-ankle pulse wave velocity (baPWV) and carotid intima media thickness (cIMT) in healthy adults aged 40 years and older in Korea.

METHODS

The present study was based on participants (n = 2145 for baPWV analysis and n = 2494 for cIMT analysis) who visited three times during 2005-2013 (median 5.3 years of follow-up). We used both dietary Na intake and Na:K at baseline and its average (baseline, 2nd, 3rd), which was obtained from food frequency questionnaire (FFQ) as exposure at every visit. baPWV and cIMT levels at the third visit and change from baseline to the third visit were used to represent the level of subclinical vascular damage.

RESULTS

After adjustment for potential confounders, significant positive relationships between dietary Na intake and both baPWV_3rd and cIMT_3rd were observed (baPWV: p for trend ≤ 0.0001 for Na_average; cIMT: p for trend = 0.013 for Na_average). Compared with Na:Ks less than 1.0, the levels of both baPWV and cIMT were higher for participants with Na:Ks over 1.0 (baPWV: p for trend = 0.0002 for Na:K_average; cIMT: p for trend = 0.005 for Na:K_average). Similar significant trends were shown in relationships between dietary Na intake and Na:K and changes in baPWV and cIMT levels.

CONCLUSIONS

In conclusion, dietary Na intake and Na:K may be positively linked to subsequent baPWV and cIMT levels in adults aged 40 years and older in Korea. Our findings may provide informative evidence on subclinical vascular damage, particularly for populations with relatively high dietary Na intake and low dietary K intake.

Enhanced angiotensin II induced sodium appetite in renovascular hypertensive rats

Renovascular hypertensive 2-kidney, 1-clip (2K1C) rats have an increased activity of the renin-angiotensin system and an initial transitory increase in daily water and NaCl intake. However, the dipsogenic and natriorexigenic responses to angiotensin II (ANG II) have not been tested yet in 2K1C rats. Therefore, in the present study, we evaluated water and 0.3 M NaCl intake induced by water deprivation (WD)-partial rehydration (PR) or intracerebroventricular (icv) ANG II in 2K1C rats. In addition, the cardiovascular changes to these treatments were also evaluated. Male Holtzman rats received a silver clip around the left renal artery to induce 2K1C renovascular hypertension. In the 5th week, a group of animals received a guide cannula in the lateral ventricle for icv injections. Daily water intake increased from the 3rd week after surgery and remained elevated until the 6th week (last recording week), whereas daily 0.3 M NaCl intake transiently increased from the 2nd to the 5th week after surgery. On the 6th week, in spite of comparable daily 0.3 M NaCl intake between 2K1C and sham rats, WD-PR and icv ANG II induced an increased 0.3 M NaCl intake in 2K1C rats. Water intake induced by WD-PR, not by icv ANG II, also increased in 2K1C rats. The increase in arterial pressure to WD-PR or icv ANG II was similar in sham and 2K1C rats. Therefore, these results suggest that 2K1C rats are more responsive to the natriorexigenic effects of ANG II, whereas other responses to ANG II are not modified.