Evaluation of measurement error in 24-hour dietary recall for assessing sodium and potassium intake among US adults - National Health and Nutrition Examination Survey (NHANES), 2014

Salt added at the table, APOE genotype and incident dementia

BACKGROUND

The frequency of salt added at the table (i.e., to food after it has been prepared, during consumption) could reflect an individual's long-term dietary preference and habitual intake in Western countries. However, little is known about the association between the frequency of salt added at the table and incident dementia. This study investigates the association of the frequency of salt added at the table with the risk of dementia and explores differences in the associations among people with apolipoprotein E ε4 genotypes.

METHODS

Individuals indicated whether they added salt to their food at the table (salt used for cooking was not included) "never/rarely", "sometimes", "usually", or "always". Cox proportional hazards models were used to compute hazard ratios with 95 % confidence intervals and evaluate the association between the frequency of salt added at the table and incident dementia.

RESULTS

We observed a graded relation between the frequency of salt added at the table and spot urine sodium concentrations and estimated 24-h sodium excretion. Over a median follow-up of 13.7 years, there were 9373 cases of all-cause dementia, including 4119 of Alzheimer's disease and 2052 of vascular dementia. With a higher frequency of salt added at the table, the risk of all-cause dementia, Alzheimer's disease and vascular dementia increased in a monotonic manner after adjustment for potential confounding factors (all P-trend <0.001). These associations of the frequency of salt added at the table with the risks of all-cause dementia, Alzheimer's disease and vascular dementia were greater in apolipoprotein E ε4 heterozygotes and homozygotes.

CONCLUSION

Our study showed that a higher frequency of salt added at the table was associated with a higher risk of incident dementia. This positive association was more prominent among individuals with apolipoprotein E ε4 heterozygotes and homozygotes.

Assessment of Dietary Sodium, Potassium and Sodium-Potassium Ratio Intake by 72 h Dietary Recall and Comparison with a 24 h Urinary Sodium and Potassium Excretion in Dominican Adults

Background: PAHO-WHO reports that sodium intake is currently high in the Caribbean. The objective was to estimate sodium (Na) and potassium (K) intakes by 72 h dietary recall and compare them with those obtained from 24 h urinary excretion in Dominican adults. Methods: A total of 69 adults (33 men) completed a 3-day dietary recall with emphasis on added salt and seasonings. The 24 h urine samples were analysed by indirect potentiometry using the membrane ion-selective electrode technique. The WHO-PAHO Questionnaire on Knowledge, Attitudes and Behaviour toward Dietary Salt and Health was completed. Results: Dietary Na intake ranged from 1.0 to 8.3 g. Median dietary and urinary Na concentrations were similar (2.7 and 2.5 mmol/d). Mean dietary Na and K concretertentrations were higher than those excreted in 24 h urine (133.0 ± 59.7 vs. 103.7 ± 44.5 mmol Na/d, p = 0.001; 69.0 ± 21.0 vs. 36 ± 16.3 mmol K/d, p < 0.001). The Na-to-K ratio was lower in dietary than in 24 h urine samples (2.0 ± 1.1 vs. 3.2 ± 1.6 mmol/d, p < 0.001). Urinary Na concentration was associated with sex (r = 0.280, p = 0.020) and obesity (r = 0.244, p = 0.043) and K with sex (r = 0.356, p = 0.003). Urinary Na-to-K was inversely related to age (r= -0.291, p = 0.015). Sex and obesity explained 11% of the variance in urinary Na concentration and sex only of the variance in urinary K concentration. The only significant correlation between dietary and urinary concentrations was that of K (r = 0.342, p = 0.004). This correlation matrix, controlled for overweight and sex, maintained the level of significance and was equal in almost 12% of the data. Conclusions: These data, which are the first data on Na and K intakes in Dominicans assessed by dietary assessment, showed a higher mean sodium intake (mean of dietary recall and urinary excretion data: 2.7 g Na, 6.8 g salt/day) and a lower K intake (2.06 g/day) than the WHO recommendations (<2.0 g Na, ≥3.5 g K). Potassium, but not sodium, intake from 72 h food recall and 24 h urinary excretion showed a correlation when controlling for sex and obesity, but not enough to consider them interchangeable.

Dietary patterns derived by reduced rank regression, macronutrients as response variables, and variation by economic status: NHANES 1999-2018

PURPOSE

Macronutrient intakes vary across people and economic status, leading to a disparity in diet-related metabolic diseases. This study aimed to provide insight into this by: (1) identifying dietary patterns in adults using reduced rank regression (RRR), with macronutrients as response variables, and (2) investigating the associations between economic status and macronutrient based dietary patterns, and between dietary patterns with central obesity (waist circumference) and systemic inflammation (C-reactive protein [CRP]).

METHODS

41,849 US participants from the National Health and Nutrition Examination Survey (NHANES), 1999-2018 were included. The percentages of energy from protein, carbohydrates, saturated fats, and unsaturated fats were used as response variables in RRR. Multivariable generalized linear models with Gaussian distribution were employed to investigate the associations.

RESULTS

Four dietary patterns were identified. Economic status was positively associated with both the high fat, low carbohydrate [βHighVsLow = 0.22; 95% CI: 0.16, 0.28] and high protein patterns [βHighVsLow = 0.07; 95% CI: 0.03, 0.11], and negatively associated with both the high saturated fat [βHighVsLow = -0.06; 95% CI: -0.08, -0.03] and the low alcohol patterns [βHighVsLow = -0.08; 95% CI; -0.10, -0.06]. The high saturated fat pattern was positively associated with waist circumference [βQ5VsQ1 = 1.71; 95% CI: 0.97, 2.44] and CRP [βQ5VsQ1 = 0.37; 95% CI: 0.26, 0.47].

CONCLUSION

Macronutrient dietary patterns, which varied by economic status and were associated with metabolic health markers, may explain associations between economic status and health.

Prevalence of Cardiovascular-Kidney-Metabolic Syndrome Stages by Social Determinants of Health

IMPORTANCE

Cardiovascular-kidney-metabolic (CKM) syndrome-a novel, multistage, multisystem disorder as defined by the American Heart Association-is highly prevalent in the US. However, the prevalence of CKM stages by social determinants of health (SDOH) remains unclear.

OBJECTIVE

To investigate whether the prevalence of CKM stages varies by SDOH in US adults.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study used data from the National Health and Nutrition Examination Survey (1999-2018) and included a nationally representative sample of adults aged 30 to 79 years through complex, multistage probability sampling. Data were analyzed from April 1 to June 15, 2024.

EXPOSURES

The exposures included 5 CKM stages (ie, stages 0-4) reflecting progressive pathophysiology, with advanced (stages 3 or 4) and nonadvanced (stages 0, 1, or 2) disease. CKM stages were defined based on risk factors for metabolic syndrome, cardiovascular disease, and chronic kidney disease.

MAIN OUTCOME AND MEASURES

The main outcome was the age-standardized prevalence of CKM stages and advanced CKM stages across SDOH, including education, marital status, family income, food security, health insurance, employment, home ownership, and health care access.

RESULTS

Among 29 722 participants (weighted mean [SE] age, 50.8 [0.1] years; weighted 50.7% male), the age-standardized prevalence of CKM stages 0 to 4 was 13.6% (95% CI, 13.0%-14.3%), 29.9% (95% CI, 29.1%-30.7%), 43.7% (95% CI, 42.9%-44.5%), 4.7% (95% CI, 4.4%-5.0%), and 8.1% (95% CI, 7.6%-8.5%), respectively. Significant differences were observed in the prevalence of CKM stages across all unfavorable SDOH of interest compared with their favorable counterparts, with unemployment (18.8% [95% CI, 17.7%-20.1%] vs 11.4% [95% CI, 11.0%-11.9%]), low family income (16.1% [95% CI, 15.4%-16.8%] vs 10.1% [95% CI, 9.5%-10.7%]), and food insecurity (18.3% [95% CI, 17.1%-19.6%] vs 11.7% [95% CI, 11.2%-12.2%]) associated with an increased likelihood of advanced CKM stages. Participants with 2 or more unfavorable SDOH were more likely to have advanced CKM stages (age-standardized prevalence, 15.8% [95% CI, 15.2%-16.5%] vs 10.5% [95% CI, 9.9%-11.1%] with <2 unfavorable SDOH). Living in a rented home (15.9% [95% CI, 14.7%-17.0%] vs 9.3% [95% CI, 8.7%-9.9%] owning the home) or not living with a partner (13.2% [95% CI, 12.3%-14.3%] vs 9.2% [95% CI, 8.5%-9.8%] living with a partner) increased the likelihood of advanced CKM stages in female but not male participants.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, disparities in the prevalence of CKM stages by SDOH, particularly family income, food security, and employment, with notable sex differences, were observed in US adults. These findings highlight the need to address inequities in CKM syndrome through targeted interventions.

Association between dietary retinol intake and rheumatoid arthritis based on NHANES database

OBJECTIVE

This study focused on the investigation of the correlation between dietary retinol intake and rheumatoid arthritis (RA) using the National Health and Nutrition Examination Survey (NHANES) database.

METHODS

Data from five NHANES cycles from 2003 to 2012 were utilized for this study. Dietary retinol intake was considered as the independent variable, and RA was the dependent variable. A weighted logistic regression method was applied to construct the relational model of the two variables. Stratified analysis without adjusting for confounding factors and subgroup analysis with confounding factors adjusted were conducted to explore the association between dietary retinol intake and RA. The optimal intake of dietary retinol was determined by the restricted cubic splines (RCS) analysis.

RESULTS

22,971 samples were included in this study. The weighted logistic regression model was employed to construct the relational model of dietary retinol intake and RA (OR: 0.95, 95% CI: 0.91-0.99, p = 0.019). Stratified analysis displayed a great influence on the relational model exerted by the interaction between gender and retinol intake (p for interaction = 0.014). A significant association between retinol intake and RA was also indicated in the model adjusted for demographic characteristics (OR: 0.95, 95% CI: 0.90-1.00, p = 0.029). Subgroup analysis by gender showed that in the female population, unadjusted model (OR: 0.90, 95% CI: 0.84-0.96, p = 0.002), model adjusted for demographic characteristics only (OR: 0.89, 95% CI: 0.83-0.96, p = 0.002), and model adjusted for all confounding factors (OR: 0.91, 95% CI: 0.85-0.99, p = 0.019) indicated dietary retinol intake as a protective factor against RA. RCS analysis demonstrated that in the female population, regardless of the model used (Crude, Model I, and Model II), an intake of dietary retinol > 354.86 mcg was associated with RA disease reduction (OR < 1.0, p-non-linear < 0.05, p-overall < 0.05).

CONCLUSION

Increased dietary retinol intake was associated with RA disease reduction, particularly in the female population. Women are recommended to increase their dietary retinol intake (> 354.86 mcg) to reduce the risk of RA.

A National Study Exploring the Association between Fasting Duration and Mortality among the Elderly

(1) Background: The benefits of weight management are widely recognized, and prolonged fasting duration has become a common method for weight control. The suitability of time-restricted eating (TRE) for elderly individuals remains controversial. This study aims to examine the correlation between fasting duration and mortality within a nationally representative cohort of elderly individuals in the United States. (2) Methods: Data were extracted from a prospective cohort study conducted as part of the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Participants aged over 60 with complete data on dietary intake and mortality follow-up information were included. Fasting duration was assessed using two 24 h dietary recalls. All the participants were categorized into fasting duration quartiles. Mortality outcomes were ascertained through the National Death Index. Cox proportional hazards regression models were utilized to analyze the association between fasting duration and mortality. (3) Results: The final analysis included 10,561 elderly participants (mean age 69.89, 45.58% male). Individuals with the longest fasting duration (over 12.38 h) had a significantly higher risk of CVD mortality compared to those with a normal fasting duration (10.58-12.38 h). This elevated CVD mortality risk was particularly pronounced in males, individuals over 70 years old, and non-shift workers. A non-linear relationship was observed between fasting duration and all-cause mortality and CVD mortality. (4) Conclusions: Prolonged fasting periods are associated with a higher risk of CVD mortality in the elderly population, although this correlation is not evident for all-cause, cancer, or other-cause mortality. A fasting duration of 11.49 h correlates with the lowest mortality risk. Additionally, elderly individuals with the shortest fasting duration exhibit elevated hazard ratios for both cancer and other-cause mortality. As with any health intervention, clinicians should exercise caution when recommending a fasting regimen that is personalized to the health condition of people who are older. Further research through randomized controlled trials should be conducted to comprehensively investigate the impact of TRE on mortality.

Can sodium and potassium measured in timed voids be used as reference instruments for validating self-report instruments? Results from a urine calibration study

BACKGROUND

Sodium and potassium measured in 24-h urine collections are often used as reference measurements to validate self-reported dietary intake instruments.

OBJECTIVES

To evaluate whether collection and analysis of a limited number of urine voids at specified times during the day ("timed voids") can provide alternative reference measurements, and to identify their optimal number and timing.

METHODS

We used data from a urine calibration study among 441 adults aged 18-39 y. Participants collected each urine void in a separate container for 24 h and recorded the collection time. For the same day, they reported dietary intake using a 24-h recall. Urinary sodium and potassium were analyzed in a 24-h composite sample and in 4 timed voids (morning, afternoon, evening, and overnight). Linear regression models were used to develop equations predicting log-transformed 24-h urinary sodium or potassium levels using each of the 4 single timed voids, 6 pairs, and 4 triples. The equations also included age, sex, race, BMI (kg/m2), and log creatinine. Optimal combinations minimizing the mean squared prediction error were selected, and the observed and predicted 24-h levels were then used as reference measures to estimate the group bias and attenuation factors of the 24-h dietary recall. These estimates were compared.

RESULTS

Optimal combinations found were as follows: single voids-evening; paired voids-afternoon + overnight (sodium) and morning + evening (potassium); and triple voids-morning + evening + overnight (sodium) and morning + afternoon + evening (potassium). Predicted 24-h urinary levels estimated 24-h recall group biases and attenuation factors without apparent bias, but with less precision than observed 24-h urinary levels. To recover lost precision, it was estimated that sample sizes need to be increased by ∼2.6-2.7 times for a single void, 1.7-2.1 times for paired voids, and 1.5-1.6 times for triple voids.

CONCLUSIONS

Our results provide the basis for further development of new reference biomarkers based on timed voids.

CLINICAL TRIAL REGISTRY

clinicaltrials.gov as NCT01631240.

Validation of the Updated GloboDiet Version by Protein and Potassium Intake for the German National Nutrition Monitoring

(1) Background: The German version of GloboDiet, a software for a computer-based assessment of 24 h recalls, was intensively updated. Therefore, validation is required prior to its use in the upcoming data collection within the German National Nutrition Monitoring. (2) Methods: For this purpose, the cross-sectional ErNst study with 109 participants (57 women and 52 men) was conducted. The study provided data on 24 h GloboDiet recalls and 24 h urine samples from the same day. Protein and potassium intake, known as eligible validation markers, were compared to the measured excretion in urine. To assess the agreement between intake and excretion, the following statistical methods were used: Wilcoxon rank tests, confidence intervals, Spearman correlations, and Bland-Altman plots. (3) Results: Overall, the updated German GloboDiet version showed valid estimates of protein intake. Regarding potassium, results were ambiguous and differed depending on the statistical method applied. While the Bland-Altman plot showed a good agreement between 24 h recalls and urine samples for potassium, the correlation was weak, suggesting that 24 h recalls may underestimate true intake. (4) Conclusions: Despite the partly ambiguous results, the updated GloboDiet version linked to the current German Nutrient Database provides valid estimates of nutrient intake.

Association of dietary magnesium intake and glycohemoglobin with mortality risk in diabetic patients

BACKGROUND

Dietary magnesium intake inversely correlated to risk of death in general population. However, it is relatively unknown whether the beneficial effect remains significant in individuals with diabetes. Our study purpose is to evaluate the association of dietary magnesium intake with mortality risk in diabetic population.

METHODS

The study population is recruited from 2003-2014 National Health and Nutrition Examination Survey, totaling 2,045 adults with diabetes being included. Participants were divided based on glycohemoglobin (HbA1c < 7% and ≥ 7%) and daily dietary magnesium intake (≤ and > 250mg/day) ascertained by 24-hour dietary recall interviews.

RESULTS

The average age of the study population was 52.9±10.1 years, with 49.1% being male. During a median follow-up of 77.0 months (interquartile range: 45.0-107.0 months), a total of 223 participants died (1.5 per 1000 person-months). Our results showed that individuals with lower dietary magnesium intake (≤250mg/day) had higher risk of all-cause (HR: 1.56, 95% CI: 1.13-2.16) and other-cause (non-cardiovascular and non-cancer) mortality (HR: 1.68, 95% CI: 1.09-2.60), while cardiovascular and cancer-related mortality were similar compared with individuals with magnesium intake > 250mg/day. We also showed that the risk of all-cause (HR: 1.86, 95% CI: 1.33-2.60) and other-cause mortality (HR: 2.03, 95% CI: 1.29-3.19) were higher in individuals with poorly controlled diabetes (HbA1c ≥7.0%) compared with HbA1c <7.0%; however, the association attenuated in the subgroup of higher magnesium intake (>250mg/day). When combining HbA1c and dietary magnesium intake, we showed that individuals with HbA1c ≥ 7% and dietary magnesium intake ≤ 250 mg/day had higher all-cause and other-cause (non-cardiovascular and non-cancer) mortality risk compared with those with HbA1c < 7% and/or dietary magnesium intake > 250 mg/day.

CONCLUSION

Higher magnesium intake may help reduce mortality risk in individuals with diabetes and attenuate mortality risk of poor diabetic control.

Identifying Distinct Risk Thresholds of Glycated Hemoglobin and Systolic Blood Pressure for Rapid Albuminuria Progression in Type 2 Diabetes From NHANES (1999–2018)

Background

It is widely recognized that glycated hemoglobin (HbA1c) and systolic blood pressure (SBP) are two key risk factors for albuminuria and renal function impairment in patients with type 2 diabetes mellitus (T2DM). Our study aimed to identify the specific numerical relationship of albumin/creatinine ratio (ACR) with HbA1c and SBP among a large population of adults with T2DM.

Method

A total of 8,626 patients with T2DM were included in the data analysis from the National Health and Nutrition Examination Surveys (NHANES) (1999-2018). The multiple linear regressions were used to examine the associations of ACR with HbA1c and SBP. Generalized additive models with smooth functions were performed to identify the non-linear relations between variables and interactions were also tested.

Results

Significantly threshold effects were observed between ACR and HbA1c or SBP after multivariable adjustment, with the risk threshold values HbA1c = 6.4% and SBP = 127 mmHg, respectively. Once above thresholds were exceeded, the lnACR increased dramatically with higher levels of HbA1c (β = 0.23, 95 CI%:0.14, 0.32, P &lt; 0.001) and SBP (β = 0.03, 95 CI%:0.03, 0.04, P &lt; 0.001). Subgroup analysis showed high protein diet was related to higher ACR. In addition, a higher risk of ACR progression was observed in central obesity participants with HbA1C ≥ 6.4% or hyperuricemia participants with SBP ≥ 127 mmHg among patients withT2DM.

Conclusion

We identified thresholds of HbA1c and SBP to stratify patients with T2DM through rapid albuminuria progression. These might provide a clinical reference value for preventing and controlling diabetes kidney disease.

Associations of Vitamin B6 Intake and Plasma Pyridoxal 5'-Phosphate with Plasma Polyunsaturated Fatty Acids in US Older Adults: Findings from NHANES 2003-2004

Previous evidence suggests a potential dual impact of aging and vitamin B6 (B6) deficiency on polyunsaturated fatty acid (PUFA) metabolism; gender may influence PUFA biosynthesis. Perturbation of PUFA compositions during B6 deficiency could be linked to age-related health outcomes. However, little is known about the interrelationships between vitamin B6, PUFA, and gender in the older population. Therefore, we investigated whether gender-specific associations of B6 intake and plasma pyridoxal 5’-phosphate (PLP) concentration, respectively, with plasma PUFA concentrations and ratios (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), EPA + DHA, EPA/AA, and (EPA + DHA)/AA) existed in older adults. We further examined the relationships of adequate B6 status (PLP ≥ 20 nmol/L) with high (above median) plasma PUFA relative to deficient B6 status. This cross-sectional study analyzed 461 participants aged ≥60 years from NHANES 2003−2004. Nutrient intakes were assessed using two 24-h recalls and supplement questionnaires. PLP and PUFA concentrations were measured. Multivariate linear regression assessed the association of B6 intake and PLP with PUFA; multivariate logistic regression evaluated the relationship of adequate B6 status with high plasma PUFA, adjusting for demographic, socioeconomic, and dietary factors; physical activity; smoking; alcohol; medication; and BMI. There were interactions between gender and B6 intake on EPA (P-interaction = 0.008) and AA (P-interaction = 0.004) only, whereas no interaction existed between gender and PLP on PUFA. PLP was directly associated with EPA (β = 0.181, P = 0.002), DHA (β = 0.109, P = 0.005), EPA + DHA (β = 0.14, P = 0.002), EPA/AA (β = 0.186, P = 0.004), and (EPA + DHA)/AA (β = 0.13, P = 0.026). The odds of having high plasma EPA (adjusted (a) OR: 2.03, P = 0.049) and EPA/AA (aOR: 3.83, P < 0.0001) were greater in those with adequate B6 status compared to those with deficient B6 status. In conclusion, in US older adults, a higher PLP level was associated with a greater level of EPA, DHA, EPA + DHA, EPA/AA, and (EPA + DHA)/AA. Adequate B6 status was associated with high EPA and EPA/AA status. These findings suggest that sufficient vitamin B6 status may positively influence PUFA metabolism in older adults.

Sodium and/or fluid restriction and nutritional parameters of adult patients with heart failure: A systematic review and meta-analysis of randomized controlled trial

INTRODUCTION

Heart failure (HF) is a clinical syndrome resulting from the structural and/or functional impairment of blood supply to tissues. Congestion and edema associated with water retention are the main symptoms presented by patients. Fluid (FR) and sodium restriction are non-pharmacological measures indicated in clinical practice to mitigate this symptom, despite their low evidence level.

AIM

Assessing the impact of sodium and/or fluid restriction on nutritional parameters of adult patients with HF, based on systematic review with meta-analysis.

METHODS

The study was conducted in June 2020, on the following databases: EMBASE, PubMed/MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL) and Web of Science. Citations were also collected in the gray literature such as thesis banks and preprints. Randomized clinical trials conducted with patients in the age group 18 years, or older, who were hospitalized or under outpatient/clinical follow-up, and who were subjected to intervention based on fluid and/or sodium restriction in comparison to the control, were herein selected.

RESULTS

Although FR-based diets are effective in reducing liquid intake, they increase individuals' thirst sensation and body weight in comparison to non-FR diets. The association between this intervention and sodium restriction is also effective in reducing liquid intake as sodium intake decreases. However, the association of the most severe (<2000 mg/day) and moderate (2000-2400 mg/day) sodium restrictions with FR has reduced energy intake, although without evidence of weight change - only the most severe sodium restriction was capable of keeping individuals' thirst sensation. In addition, moderate sodium restrictions (2300 to 3000 mg/day) in association with FR were capable of decreasing urinary sodium excretion. On the other hand, prescriptions of severe or moderate sodium restriction (<2,400 mg/d) alone have reduced individuals' body weight and BMI, although they did not change their caloric intake. However, severe sodium restriction (<2,000 mg) has led to higher body weight than the low-sodium diet (2000 to 2,4000 mg/day).

CONCLUSION

Sodium restriction may not be an effective strategy because it adversely affects individuals' weight, a fact that suggests increased congestion. Weight-based FR is supported to bethe best way to individualize this non-pharmacological treatment and it does not appear to affect nutritional parameters capable of putting patients with HF at higher malnutrition risk.

No evidence of racial disparities in blood pressure salt sensitivity when potassium intake exceeds levels recommended in the US dietary guidelines

On average, black individuals are widely believed to be more sensitive than white individuals to blood pressure (BP) effects of changes in salt intake. However, few studies have directly compared the BP effects of changing salt intake in black versus white individuals. In this narrative review, we analyze those studies and note that when potassium intake substantially exceeds the recently recommended US dietary goal of 87 mmol/day, black adults do not appear more sensitive than white adults to BP effects of short-term or long-term increases in salt intake (from an intake ≤50 mmol/day up to 150 mmol/day or more). However, with lower potassium intakes, racial differences in salt sensitivity are observed. Mechanistic studies suggest that racial differences in salt sensitivity are related to differences in vascular resistance responses to changes in salt intake mediated by vasodilator and vasoconstrictor pathways. With respect to cause and prevention of racial disparities in salt sensitivity, it is noteworthy that 1) on average, black individuals consume less potassium than white individuals and 2) consuming supplemental potassium bicarbonate, or potassium rich foods can prevent racial disparities in salt sensitivity. However, the new US dietary guidelines reduced the dietary potassium goal well below the amount associated with preventing racial disparities in salt sensitivity. These observations should motivate research on the impact of the new dietary potassium guidelines on racial disparities in salt sensitivity, the risks and benefits of potassium-containing salt substitutes or supplements, and methods for increasing consumption of foods rich in nutrients that protect against salt-induced hypertension.

Trend in potassium intake and Na/K ratio in the Italian adult population between the 2008 and 2018 CUORE project surveys

BACKGROUND AND AIMS

Low potassium intake, in addition to high sodium, has been associated with higher risk of hypertension and CVD. The Study assessed habitual potassium intake and sodium/potassium ratio of the Italian adult population from 2008 to 2012 to 2018-2019 based on 24-h urine collection, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU' SALUTE national surveys.

METHODS AND RESULTS

Data were from cross-sectional surveys of randomly selected age-and-sex stratified samples of resident persons aged 35-74 years in 10 (out of 20) Italian regions. Urinary electrolyte and creatinine measurements were performed in a central laboratory. Analyses considered 942 men and 916 women, examined in 2008-2012, and 967 men and 1010 women, examined in 2018-2019. In 2008-2012, the age-standardized mean of potassium intake (urinary potassium accounts for 70% of potassium intake) was 3147 mg (95% CI 3086-3208) in men and 2784 mg (2727-2841) in women, whereas in 2018-2019, it was 3043 mg (2968-3118) and 2561 mg (2508-2614) respectively. In 2008-2012, age-adjusted prevalence of persons with an adequate potassium intake (i.e. ≥ 3510 mg/day) was 31% (95% CI 28-34%) for men and 18% (16-21%) for women; in 2018-2019, it was 26% (23-29%) and 12% (10-14%) respectively. The sodium/potassium ratio significantly decreased both in men and women.

CONCLUSIONS

The average daily potassium intake of the Italian general adult population remains lower than the WHO and EFSA recommended level. These results suggest the need of a revision to strengthen initiatives for the promotion of an adequate potassium intake at the population level.

Gender Differences in the Associations of Plasma Pyridoxal 5'-Phosphate with Plasma Polyunsaturated Fatty Acids among US Young and Middle-Aged Adults: NHANES 2003-2004

Vitamin B6-restricted diets and low plasma pyridoxal 5'-phosphate (PLP) status altered plasma polyunsaturated fatty acids (PUFA) compositions. Evidence suggests the role of gender in the metabolism of vitamin B6 and PUFA. However, no epidemiologic study examined the impact of gender on the relationship between vitamin B6 and PUFA status in adults. Thus, we investigated whether there were gender differences in the association of vitamin B6 intake and plasma PLP concentration with plasma PUFA concentrations and ratios (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), EPA + DHA, EPA/AA, (EPA + DHA)/AA) in US young/middle-aged adults. In total, 864 participants (20-59 years; 484 men, 380 women) from the National Health and Nutrition Examination Survey (NHANES) 2003-2004 were used for this cross-sectional study. Nutrient intakes were estimated from two 24 h recalls and supplement questionnaires; plasma PLP and PUFA were measured. Multivariate linear regression was utilized to obtain unstandardized (b) and standardized (β) coefficients. Covariates included demographic, socioeconomic, dietary variables, physical activity level, cigarette smoking status, alcohol consumption, prescription medication use, and BMI. There were significant interactions between gender and PLP on EPA (P-interaction = 0.004), DHA (P-interaction = 0.020), EPA + DHA (P-interaction = 0.010), EPA/AA (P-interaction = 0.002), (EPA + DHA)/AA (P-interaction = 0.004), whereas no interaction between gender and B6 intake existed. In gender-stratified analyses, in men, PLP was positively associated with EPA (β = 0.138, b = 0.104, p = 0.0004), DHA (β = 0.101, b = 0.058, p = 0.036), EPA + DHA (β = 0.125, b = 0.073, p = 0.005), EPA/AA (β = 0.144, b = 0.099, p = 0.0002), (EPA + DHA)/AA (β = 0.123, b = 0.068, p = 0.005). However, no associations between PLP and PUFA existed in women. In conclusion, gender differences were found in the relationships between plasma PLP and plasma EPA, DHA, EPA + DHA, EPA/AA, and (EPA + DHA)/AA, with significant direct associations in men only among US young/middle-aged adults.

Assessment of polyunsaturated fatty acids: A self-report and biomarker assessment with a racially and ethnically diverse sample of women

Polyunsaturated fatty acids (PUFAs) play an important role in human health, influencing chronic disease and mortality. Food Frequency Questionnaires (FFQs) are widely used to assess self-reported diet, but they can be subject to a variety of errors. Accordingly, an accurate assessment of diet is crucial in nutrition research. This study examined the association between a widely-used self-report measure of PUFAs (Diet History Questionnaire-II: DHQ-II) with the proportion of PUFA in red blood cell (RBC) membranes, and examined whether this relationship was moderated by race/ethnicity. In a racially and ethnically diverse sample of 132 female participants (M_age = 21.97±3.98, range 18 to 42 years), bivariate correlations and linear regression analyses demonstrated associations between DHQ-II and proportion of nutrients in RBCs for omega-3 fatty acids EPA (r = 0.39, ß = 0.38, p < .01), DHA (r = 0.48, ß = 0.47, p < .01), and EPA+DHA (r = 0.51, β = 0.49, p < .01). No associations were found for omega-3 fatty acid ALA or omega-6 fatty acids LA or ARA. DHQ-II and RBC associations for EPA, DHA, and EPA+DHA were moderated by race/ethnicity, controlling for age. Self-report of EPA was most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals. Self-reports of DHA and EPA+DHA were most consistent with RBC proportions for Caucasian individuals, and less consistent for Black/African American individuals and Hispanic/Latina individuals, although still statistically significant. No associations were detected for Hispanic/Latina individuals (for EPA only), Asian/Pacific Islanders or individuals of mixed/other descent. The present study found that when compared to PUFA biomarkers, the DHQ-II did not assess PUFAs consistently across all racial/ethnic groups in this sample of women. Further research is needed to determine what factors contribute to weak or lacking correlations between reported fat intake and corresponding values in RBCs, including but not limited to recall errors, underestimations of fatty acids in food composition databases, insufficient DHQ-II assessment of fatty acids in general and from particular cultures, and genetic differences in fat metabolism.

Longitudinal Association Between Sodium and Potassium Intake and Physical Performance in Older Adults

BACKGROUND

Aging is associated with a progressive difficulty to maintain ion regulation, which might impair the capacity for muscle contraction. Thus, the aim of this study was to examine the association between 5-year changes in dietary intake of sodium and potassium and changes in physical performance among older adults.

METHODS

We performed a prospective study with 868 participants from the Seniors-ENRICA cohort. Diet was measured with a validated diet history and physical performance was measured with the Short Physical Performance Battery (SPPB), both in 2012 and 2017. Analyses were performed with linear regression models adjusted for sociodemographic variables, lifestyle, and morbidity, using changes in the intake of sodium and potassium and changes in the sodium/potassium ratio during follow-up as independent variables, and the continuous change in the SPPB score as the dependent variable.

RESULTS

Over 5 years of follow-up, a 1 SD increase in sodium intake (ie, 0.73 g/d) was associated with a 0.13 (95% confidence interval [CI]: 0.26-0.01) points reduction in the SPPB score, while a 1 SD increase in potassium intake (ie, 0.70 g/d) was associated with a 0.19 (0.05-0.34) points increment in the score. In addition, a 1 SD increase in the sodium-to-potassium ratio (ie, 0.30) was associated with worse SPPB (-0.58 [-0.95 to -0.21]). Participants who adhered to dietary recommendations for minerals at baseline but became noncompliant during follow-up decreased their result in the SPPB.

CONCLUSION

An increase of dietary sodium intake, a decrease of potassium intake and the resulting increment in the sodium-to-potassium ratio were prospectively associated with worse physical performance in older adults.

Relative validity and reliability of a diet risk score (DRS) for clinical practice

Introduction

Adherence to cardioprotective dietary patterns can reduce risk for developing cardiometabolic disease. Rates of diet assessment and counselling by physicians are low. Use of a diet screener that rapidly identifies individuals at higher risk due to suboptimal dietary choices could increase diet assessment and brief counselling in clinical care.

Methods

We evaluated the relative validity and reliability of a 9-item diet risk score (DRS) based on the Healthy Eating Index (HEI)-2015, a comprehensive measure of diet quality calculated from a 160-item, validated food frequency questionnaire (FFQ). We hypothesised that DRS (0 (low risk) to 27 (high risk)) would inversely correlate with HEI-2015 score. Adults aged 35 to 75 years were recruited from a national research volunteer registry (ResearchMatch.org) and completed the DRS and FFQ in random order on one occasion. To measure reliability, participants repeated the DRS within 3 months.

Results

In total, 126 adults (87% female) completed the study. Mean HEI-2015 score was 63.3 (95% CI: 61.1 to 65.4); mean DRS was 11.8 (95% CI: 10.8 to 12.8). DRS and HEI-2015 scores were inversely correlated (r=-0.6, p<0.001; R²=0.36). The DRS ranked 37% (n=47) of subjects in the same quintile, 41% (n=52) within ±1 quintile of the HEI-2015 (weighted κ: 0.28). The DRS had high reliability (n=102, ICC: 0.83). DRS mean completion time was 2 min.

Conclusions

The DRS is a brief diet assessment tool, validated against a FFQ, that can reliably identify patients with reported suboptimal intake. Future studies should evaluate the effectiveness of DRS-guided diet assessment in clinical care. Trial registration details ClinicalTrials.gov (NCT03805373).

Potassium intake, skeletal muscle mass, and effect modification by sex: data from the 2008-2011 KNHANES

BACKGROUND

A loss of muscle mass may be influenced by multiple factors. Insulin sensitivity and metabolic acidosis are associated with muscle wasting and may be improved with potassium intake. This study evaluated the association between dietary potassium intake and skeletal muscle mass.

METHODS

We performed a cross-sectional study with data obtained from the Korean National Health and Nutrition Examination Survey (KNHANES) (2008-2011). Participant's daily food intake was assessed using a 24-h recall method. Appendicular skeletal muscle mass (ASM) was calculated as the sum of muscle mass in both arms and legs, measured using dual energy X-ray absorptiometry. The skeletal muscle index (SMI) was calculated as ASM divided by height2 (kg/m2). Low muscle mass was defined as a SMI < 7.0 kg/m2 for men and < 5.4 kg/m2 for women.

RESULTS

Data from 16,558 participants (age ≥ 19 years) were analyzed. Participants were categorized into quintiles according to their potassium intake. Sex-specific differences were found in the association between potassium intake and muscle mass (PInteraction < 0.001). In men, higher potassium intake was associated with lower odds for low muscle mass; the fully adjusted odds ratios (95% confidence intervals) were 0.78 (0.60-1.03), 0.71 (0.54-0.93), 0.68 (0.51-0.90), and 0.71 (0.51-0.98) for the top four quintiles (referenced against the lowest quintile), respectively. However, this association was attenuated in women after adjusting for total energy intake. Higher potassium intakes were also associated with a greater SMI.

CONCLUSIONS

Higher dietary potassium intake decreased the odds of low muscle mass in men but not in women.

Health and Budgetary Impact of Achieving 10-Year U.S. Sodium Reduction Targets

INTRODUCTION

This study estimates the health, economic, and budgetary impact resulting from graduated sodium reductions in the commercially produced food supply of the U.S., which are consistent with draft U.S. Food and Drug Administration voluntary guidance and correspond to Healthy People 2020 objectives and the 2015-2020 Dietary Guidelines for Americans.

METHODS

Reduction in mean U.S. dietary sodium consumption to 2,300 mg/day was implemented in a microsimulation model designed to evaluate prospective cardiovascular disease-related policies in the U.S.

POPULATION

The analysis was conducted in 2018-2020, and the microsimulation model was constructed using various data sources from 1948 to 2018. Modeled outcomes over 10 years included prevalence of systolic blood pressure ≥140 mmHg; incident myocardial infarction, stroke, cardiovascular disease events, and cardiovascular disease-related mortality; averted medical costs by payer in 2017 U.S. dollars; and productivity.

RESULTS

Reducing sodium consumption is expected to reduce the number of people with systolic blood pressure ≥140 mmHg by about 22% and prevent approximately 895.2 thousand cardiovascular disease events (including 218.9 thousand myocardial infarctions and 284.5 thousand strokes) and 252.5 thousand cardiovascular disease-related deaths over 10 years in the U.S. Savings from averted disease costs are expected to total almost $37 billion-most of which would be attributed to Medicare ($18.4 billion) and private insurers ($13.4 billion)-and increased productivity from reduced disease burden and premature mortality would account for another $18.2 billion in gains.

CONCLUSIONS

Systemic sodium reductions in the U.S. food supply can be expected to produce substantial health and economic benefits over a 10-year period, particularly for Medicare and private insurers.