Association between blood pressure and dietary intakes of sodium and potassium among US adults using quantile regression analysis NHANES 2007-2014

Dietary Sodium and Potassium Patterns in Adults with Food Insecurity in the Context of Hypertension Risk

Background

Food insecurity (FIS), characterized by the lack of consistent access to nutritious food, is associated with hypertension and adverse health outcomes. Despite evidence of a higher prevalence of hypertension (HTN) in patients living with FIS, there is limited data exploring the underlying mechanism.

Methods

We conducted a cross-sectional analysis of 17,015 adults aged 18-65 years, using dietary recall data from the National Health and Nutrition Examination Survey (2011-2018). Univariate and multivariable analyses were used to examine the association between FIS, HTN, and dietary sodium and potassium levels.

Results

Individuals reporting FIS had a significantly lower mean intake of potassium (2.5±0.03 gm) compared to those in food-secure households (2.74±0.02 gm). No significant difference was found in the mean dietary sodium intake based on food security status. Non-Hispanic Black participants showed a high prevalence of HTN and FIS. While Non-Hispanic White and Hispanic participants had a high prevalence of FIS, it did not appear to influence their risk of HTN.

Conclusions

Adults with FIS and HTN were more likely to report a lower dietary potassium intake. Increasing access to healthy foods, particularly potassium-rich foods, for individuals facing FIS, may contribute to reducing the HTN prevalence and improving cardiovascular outcomes.

The World Hypertension League Science of Salt: a regularly updated systematic review of salt and health outcomes studies (Sept 2019 to Dec 2020)

The World Hypertension League Science of Salt health outcomes review series highlights high-quality publications relating to salt intake and health outcomes. This review uses a standardised method, outlined in previous reviews and based on methods developed by WHO, to identify and critically appraise published articles on dietary salt intake and health outcomes. We identified 41 articles published between September 2019 to December 2020. Amongst these, two studies met the pre-specified methodological quality criteria for critical appraisal. They were prospective cohort studies and examined physical performance and composite renal outcomes as health outcomes. Both found an association between increased/higher sodium intake and poorer health outcomes. Few studies meet criteria for high-quality methods. This review adds further evidence that dietary salt reduction has health benefits and strengthens evidence relating to health outcomes other than blood pressure and cardiovascular disease. We observe that most studies on dietary sodium do not have adequate methodology to reliably assess sodium intake and its association with health outcomes.

Gender-specific association between carbohydrate consumption and blood pressure in Chinese adults

Background

The association between dietary carbohydrate consumption and blood pressure (BP) is controversial. The present study aimed to evaluate the possible gender-specific association of carbohydrate across the whole BP distribution.

Method

Cross-sectional survey including 2241 rural adults was conducted in northwestern China in 2010. BP was measured by trained medical personnel. Dietary information was collected by semiquantitative Food-Frequency Questionnaire. Multivariate quantile regression model was used to estimate the association between total carbohydrates consumption and systolic BP (SBP) and diastolic BP (DBP) at different quantiles. Gender-specific β coefficient and its 95% CI was calculated.

Results

The average carbohydrate intake was 267.4 (SD 112.0) g/day in males and 204.9 (SD 90.7) g/day in females, with only 10.6% of males and 6.5% females consumed at least 65% of total energy from carbohydrates. And more than 80% carbohydrates were derived from refined grains. In females, increased total carbohydrates intake was associated with adverse SBP and DBP. An additional 50 g carbohydrates per day was positively associated with SBP at low and high quantiles (10th-20th and 60th-80th) and with DBP almost across whole distribution (30th-90th), after adjusting for age, fortune index, family history of hypertension, body mass index, physical activity level, alcohol intake and smoke, energy, two nutrient principal components, protein and sodium intake. Both relatively low and high carbohydrate intake were associated with increased SBP, with minimum level observed at 130-150 g carbohydrate intake per day from restricted cubic splines. However, no significant associations were observed in males.

Conclusions

Higher total carbohydrates consumption might have an adverse impact on both SBP and DBP in Chinese females but not males. Additionally, the positive association varies across distribution of BP quantiles. Further research is warranted to validate these findings and clarify the causality.

Dietary Sodium Intake and Health Indicators: A Systematic Review of Published Literature between January 2015 and December 2019

As the science surrounding population sodium reduction evolves, monitoring and evaluating new studies on intake and health can help increase our understanding of the associated benefits and risks. Here we describe a systematic review of recent studies on sodium intake and health, examine the risk of bias (ROB) of selected studies, and provide direction for future research. Seven online databases were searched monthly from January 2015 to December 2019. We selected human studies that met specified population, intervention, comparison, outcome, time, setting/study design (PICOTS) criteria and abstracted attributes related to the study population, design, intervention, exposure, and outcomes, and evaluated ROB for the subset of studies on sodium intake and cardiovascular disease risks or indicators. Of 41,601 abstracts reviewed, 231 studies were identified that met the PICOTS criteria and ROB was assessed for 54 studies. One hundred and fifty-seven (68%) studies were observational and 161 (70%) focused on the general population. Five types of sodium interventions and a variety of urinary and dietary measurement methods were used to establish and quantify sodium intake. Five observational studies used multiple 24-h urine collections to assess sodium intake. Evidence mainly focused on cardiovascular-related indicators (48%) but encompassed an assortment of outcomes. Studies varied in ROB domains and 87% of studies evaluated were missing information on ≥1 domains. Two or more studies on each of 12 outcomes (e.g., cognition) not previously included in systematic reviews and 9 new studies at low ROB suggest the need for ongoing or updated systematic reviews of evidence on sodium intake and health. Summarizing evidence from assessments on sodium and health outcomes was limited by the various methods used to measure sodium intake and outcomes, as well as lack of details related to study design and conduct. In line with research recommendations identified by the National Academies of Science, future research is needed to identify and standardize methods for measuring sodium intake.

Electrolytes and Cardiovascular Disease Risk

The relationship between sodium intake and blood pressure is a well-studied phenomenon; however, the impact of sodium intake on cardiovascular disease risk and mortality is controversial. Recent studies conclude that weak evidence exists to support sodium restriction for the prevention of cardiovascular mortality in normotensive and hypertensive adults, suggesting that sodium restriction may be an ineffective strategy for disease prevention. Further evidence points to the importance of balancing sodium and potassium intake, a balance commonly achieved with a healthier diet containing greater quantities of fruits and vegetables. The purpose of this article is to highlight dietary strategies that may prove to be more effective in reducing cardiovascular disease risk. Limitations of current methods used to estimate nutrient intake are described as they relate to this topic. Further research is needed to advance understanding of various aspects of dietary intake that are health protective and allow for the development of more effective public education strategies.