Urinary sodium excretion and its association with blood pressure in Nigeria: A nationwide population survey

Community-level dietary intake of sodium, potassium, and sodium-to-potassium ratio as a global public health problem: a systematic review and meta-analysis

Background

Widespread adoption of a westernized diet represents a major lifestyle change characterized by substantially higher sodium consumption and lower potassium intake, which is related to cardiovascular morbidity.

Methods

We performed a systematic review and meta-analysis over published studies in accordance with quantifying the dietary intake of sodium and potassium of the universal population across the world. The PubMed, EMBASE, Cochrane Library, and Google Scholar databases were used to find research that pronounced 24-hour urinary sodium or potassium excretion (reference period: 2014-2021). The effect size was estimated using the fixed-effect model; sub-group analysis become accomplished to determine urinary sodium and potassium excretion disaggregated by geographical location. Publication bias became evaluated the usage of graphical funnel plot. Data analysis was performed using STATA 16.

Results

Forty-three studies (n= 62,940) qualified the selection criteria. The mean urinary excretion of sodium and potassium was 156.73 mmol/24h [95% confidence interval (CI), 148.98-164.47] and 48.89 mmol/24 h (95% CI, 43.61-54.17), respectively; the mean urinary sodium/potassium ratio was 3.68 (95% CI, 2.96-4.40).

Conclusions

This updated systematic review highlights excessively high dietary intake of sodium and low intake of potassium at the community level in most parts of the world. The urinary Na/K ratio exceeded the level recommended by the WHO guidelines.

Effect of Salt Reduction Interventions in Lowering Blood Pressure and Salt Intake in Zhejiang Province, China, 2017-2021: A Randomized Controlled Trial

BACKGROUND

Addressing high-salt diets in China through interventions can significantly reduce blood pressure (BP) and the associated health risks.

OBJECTIVE

This study aims to evaluate the effectiveness of a comprehensive salt reduction intervention implemented across counties in Zhejiang Province, focusing on system establishment, extensive publicity, and targeted population interventions.

METHODS

The Salt Reduction and Hypertension Prevention Project was initiated in Zhejiang Province. Cross-sectional surveys were conducted before the intervention and after. The research commenced in 2017 with a baseline survey involving 7512 participants from five counties. Four counties were randomly selected for the intervention, implementing a multifaceted salt reduction strategy, while one county served as a reference without any intervention. The primary outcomes measured were changes in BP and 24 h urinary sodium and potassium excretion.

RESULTS

Following the intervention, 24 h urinary potassium excretion experienced a significant increase, rising from 1441.3 (SD 681.9) to 1676.9 (SD 931.4) mg per day, p < 0.001. Utilizing a linear mixed-effects model, the adjusted net difference in urinary sodium changes was calculated to be 394.1 mg per day (95% CI, 133.2 to 655.0) (p = 0.003). There was a notable reduction in systolic blood pressure (SBP) from 131.2 (SD 19.2) to 129.8 mmHg (SD 18.0), and diastolic blood pressure (DBP) also decreased from 80.8 (SD 10.8) to 78.9 mmHg (SD 10.2), p < 0.001. The adjusted net differences for SBP and DBP between the intervention and reference groups were 1.3 (95%CI, 0.5 to 2.1) and 1.4 mmHg (95%CI, 0.9 to 2.0), respectively, p < 0.001.

CONCLUSIONS

The findings indicate that a multi-sectoral approach, combined with extensive public awareness initiatives and precisely targeted interventions, can significantly increase urinary potassium excretion and reduce sodium and blood pressure.

Dietary Sources of Sodium in Nigerian Adults From 3 Geographic Regions: A Population-Based Cross-Sectional Study

Background

To address the growing burden of hypertension and related diseases, Nigeria seeks to reduce excess dietary sodium through policymaking. The current study aims to describe the levels and sources of dietary sodium intake among Nigerian adults to inform targeted policies for reducing sodium intake.

Methods

From June 2023 to July 2023, adults aged 18 to 70 years old were recruited from the Federal Capital Territory, Kano States, and Ogun States to participate in a population-based, cross-sectional non-communicable diseases survey. Data were also collected to assess levels and dietary sources of sodium through four 24-hour dietary recalls by trained study personnel with 90.7% response rate. Concurrent 24-hour urine sodium data were collected. The primary analyses included the distribution of sodium intake and sources of sodium, overall and by sex and state. Results were adjusted to the Nigerian population. Multivariate regression models evaluated associations between baseline sociodemographic factors and sodium intake.

Results

Among 537 participants, 365 (68.0%) were female, and median (Interquartile range) age was 38 (27, 48) years. Adjusted median (IQR) daily sodium intake according to 24-hour dietary recalls was 3,803 (2,663, 5,085) mg per day with higher intake reported among males (males: 3,878 [2,663, 5,032] mg/dl; females: 3,415 [2,373, 4,689], p<.0001). Two-thirds (67.0%) of the sodium intake was from home-cooked meals. Nearly half (48.7%) of sodium came from discretionary sources, including 21.4% from bouillon. Salt and yaji spice added at the table accounted for 9.1% of sodium intake and was highest among females (18.8%) and males (13.7%) in Kano. On the other hand, sodium from street food was highest in males (35.9%) and females (34.2%) in Ogun. After adjustment, older participants and those with higher education had lower daily sodium intake compared to younger participants and those with less education, respectively. Results were similar when excluding individuals with cardiovascular disease or hypertension.

Conclusions

Adults in the Federal Capital Territory, Kano, and Ogun consume nearly twice the recommended level of dietary sodium. Most dietary sodium intake came from home cooked foods, nearly half of which came from discretionary sources, which has important policy implications for SHAKE package implementation.

Dietary patterns associated with hypertension among stroke-free indigenous Africans: insights from the Stroke Investigative Research and Educational Network study

BACKGROUND

The dietary factors associated with the high burden of hypertension among indigenous Africans remain poorly understood. We assessed the relationship between dietary patterns and hypertension among indigenous Africans.

METHOD

In this study, 1550 participants with hypertension matched (for age: ± 5 years, sex and ethnicity) with 1550 participants without hypertension were identified from the stroke-free population in the Stroke Investigative Research and Educational Network study in Ghana and Nigeria. Food consumption was assessed using a food frequency questionnaire, and dietary information was summarized using principal component analysis to identify seven dietary patterns. Conditional logistic regression was applied to compute the odds ratio (OR) and 95% confidence interval (CI) for the risk of hypertension by tertiles of dietary patterns adjusting for age, education, income, smoking, alcohol use, physical inactivity, family history of cardiovascular diseases, obesity and salt intake at a two-sided P less than 0.05.

RESULTS

Multivariable-adjusted OR [95% confidence interval (CI)] for risk of hypertension by second and third tertiles [using the lowest (first) tertile as reference] of dietary patterns were 0.62 (0.48-0.80), 0.70 (0.54-0.90) for whole grains and fruit drinks; 0.87 (0.68-1.12), 0.83 (0.64-1.08) for fruits; 0.85 (0.65-1.10), 0.97 (0.75-1.26) for vegetables, legumes and potatoes; 0.78 (0.60-1.00), 0.84 (0.65-1.08) for fried foods and sweetened drinks; 1.13 (0.88-1.45), 0.80 (0.62-1.03) for poultry product and organ meat; 1.11 (0.86-1.43), 0.88 (0.68-1.14) for red meat; and 1.14 (0.88-1.48), 1.09 (0.84-1.43) for processed foods ( P  < 0.05).

CONCLUSION

A higher adherence to dietary consumption of whole grains and fruits was inversely associated with low odds of hypertension in this population.

Rural-urban difference in the prevalence of hypertension in West Africa: a systematic review and meta-analysis

Urbanisation is considered a major contributor to the rising prevalence of hypertension in West Africa, yet the evidence regarding rural-urban differences in the prevalence of hypertension in the region has been mixed. A systematic literature search of four electronic databases: PubMed, Embase, African Journals Online, and WHO's African Index Medicus; and reference lists of eligible studies was carried out. Original quantitative studies describing the rural-urban difference in the prevalence of hypertension in one or more countries in West Africa, and published in English language from the year 2000 to 2021 were included. A random effects meta-analysis model was used to estimate the odds ratio of hypertension in rural compared to urban locations. A limited sex-based random effects meta-analysis was conducted with 16 studies that provided sex-disaggregated data. Of the 377 studies screened, 22 met the inclusion criteria (n = 62,907). The prevalence of hypertension was high in both rural, and urban areas, ranging from 9.7% to 60% in the rural areas with a pooled prevalence of 27.4%; and 15.5% to 59.2% in the urban areas with a pooled prevalence of 33.9%. The odd of hypertension were lower in rural compared to urban dwellers [OR 0.74, 95% CI: 0.66-0.83; p < 0.001]. The pooled prevalence of hypertension was 32.6% in males, and 30.0% in females, with no significant difference in the odds of hypertension between the sexes [OR 0.91, 95% CI: 0.8-1.05, p = 0.196]. Comprehensive hypertension control policies are needed for both rural, and urban areas in West Africa, and for both sexes.

Estimation of 24-hour urinary sodium and potassium excretion among Chinese adults: a cross-sectional study from the China National Nutrition Survey

BACKGROUND

High-sodium intake is one of the most important risk factors for hypertension and cardiovascular disease, yet reliable national estimates of sodium intake in Chinese adults have not been reported.

OBJECTIVES

We estimated 24-h urinary sodium and potassium excretion and population daily sodium and potassium intake of Chinese adults for the first time at a national level.

METHODS

A nationally representative cross-sectional survey was conducted to collect 24-h urine specimens from Chinese adults aged ≥18 y as part of the China National Nutrition Survey 2015. Finally, 10,114 participants (4932 males and 5182 females) with complete 24-h urine specimens were included in the analysis. Estimates of mean urinary electrolyte excretion and demographic, socioeconomic, and health characteristics were used with weighted coefficients that accounted for sample selection probabilities, poststratification weighting, and nonresponse rates.

RESULTS

The estimation of overall weighted mean 24-h urinary sodium excretion was 4121 mg (95% confidence interval [CI]: 3993, 4250), 4155 mg (95% CI: 3993, 4317) in males and 4081 mg (95% CI: 3953, 4209) in females (P for sex difference = 0.36). Overall mean 24-h urinary potassium excretion was 1534 mg (95% CI: 1492, 1577), 1468 mg (95% CI: 1424, 1513) in males and 1614 mg (95% CI: 1569-1660) in females (P for sex difference <0.001). Mean 24-h urinary sodium excretion was significantly higher in rural adults (4350 mg; 95% CI: 4217, 4483) than in urban residents (3909 mg; 95% CI: 3739, 4080; P < 0.001), and in northern residents (4388 mg; 95% CI: 4237, 4539) than in southern residents (3998 mg; 95% CI: 3832, 4163; P = 0.002).

CONCLUSIONS

The first nationwide survey with 24-h urine collection confirmed that mean sodium intake in Chinese adults was more than twice the upper limit, whereas mean potassium intake was <60% of the lower limit, recommended by the World Health Organization. Urgent measures should be taken to reduce sodium intake and increase potassium intake in China.

Stakeholder perspectives on Nigeria's national sodium reduction program: Lessons for implementation and scale-up

BACKGROUND

To reduce excess dietary sodium consumption, Nigeria's 2019 National Multi-sectoral Action Plan (NMSAP) for the Prevention and Control of Non-communicable Diseases includes policies based on the World Health Organization SHAKE package. Priority actions and strategies include mandatory sodium limits in processed foods, advertising restrictions, mass-media campaigns, school-based interventions, and improved front-of-package labeling. We conducted a formative qualitative evaluation of stakeholders' knowledge, and potential barriers as well as effective strategies to implement these NMSAP priority actions.

METHODS

From January 2021 to February 2021, key informant interviews (n = 23) and focus group discussions (n = 5) were conducted with regulators, food producers, consumers, food retailers and restaurant managers, academia, and healthcare workers in Nigeria. Building on RE-AIM and the Consolidated Framework for Implementation Research, we conducted directed content qualitative analysis to identify anticipated implementation outcomes, barriers, and facilitators to implementation of the NMSAP sodium reduction priority actions.

RESULTS

Most stakeholders reported high appropriateness of the NMSAP because excess dietary sodium consumption is common in Nigeria and associated with high hypertension prevalence. Participants identified multiple barriers to adoption and acceptability of implementing the priority actions (e.g., poor population knowledge on the impact of excess salt intake on health, potential profit loss, resistance to change in taste) as well as facilitators to implementation (e.g., learning from favorable existing smoking reduction and advertising strategies). Key strategies to strengthen NMSAP implementation included consumer education, mandatory and improved front-of-package labeling, legislative initiatives to establish maximum sodium content limits in foods and ingredients, strengthening regulation and enforcement of food advertising restrictions, and integrating nutrition education into school curriculum.

CONCLUSION

We found that implementation and scale-up of the Nigeria NMSAP priority actions are feasible and will require several implementation strategies ranging from community-focused education to strengthening current and planned regulation and enforcement, and improvement of front-of-package labeling quality, consistency, and use.

Sodium Content and Labelling of Packaged Foods and Beverages in Nigeria: A Cross-Sectional Study

Increased consumption of unhealthy processed foods, particularly those high in sodium, is a major risk factor for cardiovascular diseases. The nutrition information on packaged foods can help guide consumers toward products with less sodium and support government actions to improve the healthiness of the food supply. The aims of this study were to estimate the proportion of packaged foods displaying nutrition information for sodium and other nutrients specified by Nigerian nutrition labelling regulations and to determine the amount of sodium in packaged foods sold in Nigeria using data from the nutritional information panel. Data were collected from November 2020 to March 2021 from in-store surveys conducted in supermarkets in three states. A total of 7039 products were collected. Overall, 91.5% (n = 6439) provided only partial nutrition information, 7.0% (n = 495) provided no nutritional information, and only 1.5% (n = 105) displayed a nutrient declaration that included all nutrients specified by 2019 Nigerian regulations. Some form of sodium content information was displayed for 86% of all products (n = 6032), of which around 45% (n = 2689) expressed this as 'salt' and 59% (n = 3559) expressed this as 'sodium', while a small number of food products had both 'salt' and 'sodium' content (3.6%). Provision of sodium or salt information on the label varied between food categories, ranging from 50% (vitamins and supplements, n = 2/4) to 96% (convenience foods, n = 44/46). Food categories with the highest median sodium content were 'meat and meat alternatives' (904 mg/100 g), 'sauces, dressings, spreads, and dips' (560 mg/100 g), and 'snack foods' (536 mg/100 g), although wide variation was often observed within categories. These findings highlight considerable potential to improve the availability and consistency of nutrition information on packaged products in Nigeria and to introduce further policies to reduce the amount of sodium in the Nigerian food supply.