Neighborhood Socioeconomic Disadvantage Is Associated with Higher Ratio of 24-Hour Urinary Sodium to Potassium in Young Japanese Women

Baseline knowledge about hypertension and sociodemographic factors related to salt intake behavior among hypertensive individuals in a rural community of Bangladesh: Substudy of a randomized controlled trial

Background

Excess salt consumption increases blood pressure, and therefore, this substudy was designed among rural hypertensive individuals to assess the baseline knowledge about hypertension (HTN), and dietary salt intake behavior and identify the potential predictors for urinary salt excretion in Bangladesh.

Material and Methods

A total of 420 participants were enrolled after meeting the eligibility criteria during the 12 months of the study period. The participants received behavior changes related to short message services (SMS) and face-to-face education from community health workers.

Results

Our study results found that 80% of the participants had positive knowledge of HTN. This study showed that the mean value of overnight urinary sodium excretion was 10.65 ± 3.00 at the 1st-month follow-up and 10.24 ± 3.03 at the endline. We found that mid-upper arm circumference (MUAC), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were significantly related to higher salt intake (P = 0.009, P = 0.011, and P = 0.005, respectively). However, participants had improved their MUAC, SBP, and DBP status in their 1st follow-up period, but still, significant associations were observed between them (P = 0.033, P = 0.011, and P = 0.002, respectively).

Conclusion

This study's results found that sodium excretion among hypertensive participants was higher, and higher urinary sodium excretion was associated with overweight and BP in adults. Nonetheless, the real salt intake practice among the Bangladeshi population is still unknown, which demands further research.

Community Income, Healthy Food Access, and Repeat Surgery for Kidney Stones

OBJECTIVE

To determine if limited food access census tracts and food swamp census tracts are associated with increased risk for repeat kidney stone surgery. And to elucidate the relationship between community-level food retail environment relative to community-level income on repeat stone surgery over time.

METHODS

Data were abstracted from the University of California, San Francisco Information Commons. Adult patients were included if they underwent at least one urologic stone procedure. Census tracts from available geographical data were mapped using Food Access Research Atlas data from the United States Department of Agriculture Economic Research Service. Kaplan-Meier curves were employed to illustrate time to a second surgical procedure over 5 years, and log-rank tests were used to test for statistically significant differences. A multivariate Cox regression model was used to generate hazard ratios for undergoing second surgery by group.

RESULTS

A total of 1496 patients were included in this analysis. Repeat stone surgery occurred in 324 patients. Kaplan-Meier curves demonstrated a statistically significant difference in curves depicting patients living in low income census tracts (LICTs) vs those not living in LICTs (P <.001). On Cox regression models, patients in LICTs had significantly higher risk of undergoing repeat surgery (P = .011). Patients from limited food access census tracts and food swamp census tracts did not have a significantly higher adjusted risk of undergoing second surgery (P = .11 and P = .88, respectively).

CONCLUSION

Income more so than food access associates with increased risk of repeat kidney stone surgery. Further research is needed to explore the interaction between low socioeconomic status and kidney stone outcomes.

Higher Neighborhood Population Density Is Associated with Lower Potassium Intake in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

Current U.S. dietary guidelines recommend a daily potassium intake of 3400 mg/day for men and 2600 mg/day for women. Sub-optimal access to nutrient-rich foods may limit potassium intake and increase cardiometabolic risk. We examined the association of neighborhood characteristics related to food availability with potassium intake in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). 13,835 participants completed a 24-h dietary recall assessment and had complete covariates. Self-reported potassium intake was calibrated with an objective 24-h urinary potassium biomarker, using equations developed in the SOL Nutrition & Physical Activity Assessment Study (SOLNAS, N = 440). Neighborhood population density, median household income, Hispanic/Latino diversity, and a retail food environment index by census tract were obtained. Linear regression assessed associations with 24-h potassium intake, adjusting for individual-level and neighborhood confounders. Mean 24-h potassium was 2629 mg/day based on the SOLNAS biomarker and 2702 mg/day using multiple imputation and HCHS/SOL biomarker calibration. Compared with the lowest quartile of neighborhood population density, living in the highest quartile was associated with a 26% lower potassium intake in SOLNAS (adjusted fold-change 0.74, 95% CI 0.59–0.94) and a 39% lower intake in HCHS/SOL (adjusted fold-change 0.61 95% CI 0.45–0.84). Results were only partially explained by the retail food environment. The mechanisms by which population density affects potassium intake should be further studied.

Lower Socioeconomic Status is Associated With Adverse Urinary Markers and Surgical Complexity in Kidney Stone Patients

OBJECTIVE

To determine if socioeconomic status (SES) correlates with severity of kidney stone disease and 24-hour urine parameters.

MATERIALS AND METHODS

An IRB approved prospectively maintained database for nephrolithiasis was retrospectively analyzed for both 24-hour urine results and surgical procedures performed from 2009 to 2019. Severely distressed communities (SDC) were categorized as those with a Distressed Communities Index (DCI), a composite measure of SES, score in the top quartile (lowest for SES). Univariate and multivariate analyses were performed to evaluate the strength of the association of DCI on: stone size at presentation, need for and type of surgical procedure, need for staged surgery and specific stone risk factors in 24-hour urine collections.

RESULTS

Surgical procedures were performed on 3939 patients (1978 women) who were not from SDC and 200 (97 women) from SDC. Patients from SDC were older (57.1 years vs 54.2 years; P = .009). Patients from SDC were more likely to undergo proportionally more invasive procedures (17.5% vs 11.6%; P = .011) and require staged surgery at a higher rate (13.0% vs 8.5%; P = .028). Men from SDC had larger stones (12.5 mm vs 9.7 mm; P = .001). Among 24-hour urine results from 2454 patients (1187 women), DCI was not correlated with sodium, calcium, magnesium, volume, oxalate, phosphate, and pH levels. Higher DCI (lower SES) correlated with lower urine citrate (P = .001) and lower urine potassium (P = .002).

CONCLUSION

SES correlates with larger stone burden at the time of urologic intervention, requires proportionally more invasive procedures and more staged procedures. Lower SES correlated with lower urine citrate and potassium.

Neighbourhood socioeconomic status and cross-sectional associations with obesity and urinary biomarkers of diet among New York City adults: the heart follow-up study

OBJECTIVE

To determine whether neighbourhood socioeconomic status (SES) is associated with body mass index (BMI), waist circumference (WC) and biomarkers of diet (urinary sodium and potassium excretion).

DESIGN

A cross-sectional study.

SETTING

The data reported were from the 2010 Heart Follow-up Study, a population-based representative survey of 1645 adults.

PARTICIPANTS

Community-dwelling diverse residents of New York City nested within 128 neighbourhoods (zip codes).

PRIMARY AND SECONDARY OUTCOME MEASURES

BMI (kg/m2) and WC (inches) were measured during in-home visits, and 24-hour urine sample was collected to measure biomarkers of diet: sodium (mg/day) and potassium (mg/day), with high sodium and low potassium indicative of worse diet quality.

RESULTS

After adjusting for individual-level characteristics using multilevel linear regressions, low versus high neighbourhood SES tertile was associated with 1.83 kg/m2 higher BMI (95% CI 0.41 to 3.98) and 251 mg/day lower potassium excretion (95% CI -409 to 93) among women only, with no associations among men (P values for neighbourhood SES by sex interactions <0.05).

CONCLUSION

Our results suggest that women may be particularly vulnerable to the effects of a socioeconomically disadvantaged neighbourhood. Future neighbourhood research should explore sex differences, as these can inform tailored interventions.

TRIAL REGISTRATION NUMBER

NCT01889589; Results.

Socioeconomic Determinants of Sodium Intake in Adult Populations of High-Income Countries: A Systematic Review and Meta-Analysis

BACKGROUND

A poorer quality diet among individuals with low socioeconomic status (SES) may partly explain the higher burden of noncommunicable disease among disadvantaged populations. Because there is a link between sodium intake and noncommunicable diseases, we systematically reviewed the current evidence on the social patterning of sodium intake.

OBJECTIVES

To conduct a systematic review and a meta-analysis of the evidence on the association between SES and sodium intake in healthy adult populations of high-income countries.

SEARCH METHODS

We followed the PRISMA-Equity guidelines in conducting a literature search that ended June 3, 2016, via MEDLINE, Embase, and SciELO. We imposed no publication date limits.

SELECTION CRITERIA

We considered only peer-reviewed articles meeting the following inclusion criteria: (1) reported a measure of sodium intake disaggregated by at least 1 measure of SES (education, income, occupation, or any other socioeconomic indicator); (2) were written in English, Spanish, Portuguese, French, or Italian; and (3) were conducted in a high-income country as defined by the World Bank (i.e., per capita national gross income was higher than $12 746). We also excluded articles that exclusively sampled low-SES individuals, pregnant women, children, adolescents, elderly participants, or diseased patients or that reported results from a trial or intervention.

DATA COLLECTION AND ANALYSIS

As summary measures, we extracted (1) the direction (positive, negative, or neutral) and the magnitude of the association between each SES indicator and sodium intake, and (2) the estimated sodium intake according to SES level. When possible and if previously unreported, we calculated the magnitude of the relative difference in sodium intake between high- and low-SES groups for each article, applying this formula: ([value for high-SES group - value for low-SES group]/[value for high-SES group]) × 100. We considered an association significant if reported as such, and we set an arbitrary 10% relative difference as clinically relevant and significant. We conducted a meta-analysis of the relative difference in sodium intake between high- and low-SES groups. We included articles in the meta-analysis if they reported urine-based sodium estimates and provided the total participant numbers in the low- and high-SES groups, the estimated sodium intake means for each group (in mg/day or convertible units), and the SDs (or transformable measures). We chose a random-effects model to account for both within-study and between-study variance.

MAIN RESULTS

Fifty-one articles covering 19 high-income countries met our inclusion criteria. Of these, 22 used urine-based methods to assess sodium intake, and 30 used dietary surveys. These articles assessed 171 associations between SES and sodium intake. Among urine-based estimates, 67% were negative (higher sodium intake in people of low SES), 3% positive, and 30% neutral. Among diet-based estimates, 41% were negative, 21% positive, and 38% neutral. The random-effects model indicated a 14% relative difference between low- and high-SES groups (95% confidence interval [CI] = -18, -9), corresponding to a global 503 milligrams per day (95% CI = 461, 545) of higher sodium intake among people of low SES.

CONCLUSIONS

People of low SES consume more sodium than do people of high SES, confirming the current evidence on socioeconomic disparities in diet, which may influence the disproportionate noncommunicable disease burden among disadvantaged socioeconomic groups. Public Health Implications. It is necessary to focus on disadvantaged populations to achieve an equitable reduction in sodium intake to a population mean of 2 grams per day as part of the World Health Organization's target to achieve a 25% relative reduction in noncommunicable disease mortality by 2025.

Contextual poverty, nutrition, and chronic kidney disease

Nutrition plays an important role in CKD outcomes. One of the strongest factors that affects nutrition is socioeconomic status as evidenced by the large body of epidemiologic data showing that income and education are directly associated with diet quality. Apart from individual-level markers of socioeconomic status such as income and education, contextual factors such as availability of and transportation to food outlets that provide healthy food options and the density of fast-food restaurants within particular regions markedly affect the ability of individuals to comply with nutrition recommendations. This is particularly true for nutrition guidelines most specific to individuals with CKD such as the consumption of protein, saturated fat, sodium, and phosphorus, all of which have been shown to affect CKD health and are influenced by the availability of healthy food options within individual neighborhood food environments. Because of the strong association of contextual poverty with the diet quality, any serious attempt to improve the diet of CKD patients must include a discussion of the environmental barriers that each individual faces in trying to access healthy foods, and health care providers should take account of these barriers when tailoring specific recommendations.

Socioeconomic status is significantly associated with dietary salt intakes and blood pressure in Japanese workers (J-HOPE Study)

The association of socioeconomic status (SES) with nutrients intakes attracts public attention worldwide. In the current study, we examined the associations of SES with dietary salt intake and health outcomes in general Japanese workers (2,266) who participated in this Japanese occupational cohort. SES was assessed by a self-administered questionnaire. Dietary intakes were assessed with a validated, brief, self-administered diet history questionnaire (BDHQ). Multiple linear regression and stratified analysis were used to evaluate the associations of salt intake with the confounding factors. Education levels and household incomes were significantly associated with salt intake, as well as blood pressures (P < 0.05). After adjusting for age, sex and total energy intake, both years of education and household income significantly affect the salt intake (for education, β = −0.031, P = 0.040; for household income, β = −0.046, P = 0.003). SES factors also affect the risk of hypertension, those subjects with higher levels of education or income had lower risk to become hypertensive (ORs for education was 0.904, P < 0.001; ORs for income was 0.956, P = 0.032). Our results show that SES is an independent determinant of salt intake and blood pressure, in order to lower the risk of hypertension, the efforts to narrow the social status gaps should be considered by the health policy-makers.

Neighbourhood food store availability in relation to 24 h urinary sodium and potassium excretion in young Japanese women

Previous studies on the relationship of local food environment with residents' diets have relied exclusively on self-reported information on diet, producing inconsistent results. Evaluation of dietary intake using biomarkers may obviate the biases inherent to the use of self-reported dietary information. This cross-sectional study examined the association between neighbourhood food store availability and 24 h urinary Na and K excretion. The subjects were 904 female Japanese dietetic students aged 18-22 years. Neighbourhood food store availability was defined as the number of food stores within a 0.5-mile (0.8-km) radius of residence. Urinary Na and K excretion and the ratio of urinary Na to K were estimated from a single 24 h urine sample. After adjustment for potential confounding factors, neighbourhood availability of confectionery stores/bakeries was inversely associated with urinary K, and was positively associated with the ratio of Na to K (P for trend = 0.008 and 0.03, respectively). Neighbourhood availability of rice stores showed an independent inverse association with urinary K (P for trend = 0.03), whereas neighbourhood availability of supermarkets/grocery stores conversely showed an independent positive association with this variable (P for trend = 0.03). Furthermore, neighbourhood availability of fruit/vegetable stores showed an independent inverse association with the ratio of Na to K (P for trend = 0.049). In a group of young Japanese women, increasing neighbourhood availability of supermarkets/grocery stores and fruit/vegetable stores and decreasing availability of confectionery stores/bakeries and rice stores were associated with favourable profiles of 24 h urinary K (and Na) excretion.

Neighborhood socioeconomic status in relation to dietary intake and insulin resistance syndrome in female Japanese dietetic students

OBJECTIVE

An increasing number of studies in Western countries have shown that living in a socioeconomically disadvantaged neighborhood is associated with unfavorable dietary intake patterns and health status. However, information on such neighborhood socioeconomic differences in diet and health among different cultural settings, including Japan, is limited. This cross-sectional study examined the association of neighborhood socioeconomic status (SES) with dietary intake and a summary score of the insulin resistance syndrome (IRS) in a group of young Japanese women.

METHODS

Subjects were 1081 female Japanese dietetic students aged 18 to 22 y residing in 295 municipalities in Japan. Neighborhood SES index was defined by seven municipal-level variables, namely unemployment, household overcrowding, poverty, education, income, home ownership, and vulnerable group, with an increasing index signifying increasing neighborhood socioeconomic disadvantage. Dietary intake was estimated using a validated, comprehensive self-administered diet-history questionnaire. Measurements of body mass index, systolic blood pressure, fasting high-density lipoprotein cholesterol, triacylglycerol, glucose, and insulin were combined into an IRS score, with an increasing score signifying increasing levels of components of the IRS.

RESULTS

Neighborhood SES index was not associated with most of the dietary variables, body mass index, high-density lipoprotein cholesterol, triacylglycerol, or glucose. However, neighborhood SES index was significantly positively associated with systolic blood pressure, insulin, and IRS score, after adjustment for potential confounding or mediating factors, including household SES, dietary, and lifestyle factors.

CONCLUSION

Neighborhood socioeconomic disadvantage was associated with unfavorable profiles of the IRS score, but not dietary intake, in a group of young Japanese women.