Association of urinary sodium excretion with blood pressure and risk factors associated with hypertension among Cameroonian pygmies and bantus: a cross-sectional study

Addressing global disparities in blood pressure control: perspectives of the International Society of Hypertension

ABSTRACT

Raised blood pressure (BP) is the leading cause of preventable death in the world. Yet, its global prevalence is increasing, and it remains poorly detected, treated, and controlled in both high- and low-resource settings. From the perspective of members of the International Society of Hypertension based in all regions, we reflect on the past, present, and future of hypertension care, highlighting key challenges and opportunities, which are often region-specific. We report that most countries failed to show sufficient improvements in BP control rates over the past three decades, with greater improvements mainly seen in some high-income countries, also reflected in substantial reductions in the burden of cardiovascular disease and deaths. Globally, there are significant inequities and disparities based on resources, sociodemographic environment, and race with subsequent disproportionate hypertension-related outcomes. Additional unique challenges in specific regions include conflict, wars, migration, unemployment, rapid urbanization, extremely limited funding, pollution, COVID-19-related restrictions and inequalities, obesity, and excessive salt and alcohol intake. Immediate action is needed to address suboptimal hypertension care and related disparities on a global scale. We propose a Global Hypertension Care Taskforce including multiple stakeholders and societies to identify and implement actions in reducing inequities, addressing social, commercial, and environmental determinants, and strengthening health systems implement a well-designed customized quality-of-care improvement framework.

Preventive Potential of the Aqueous Extract of the Mixture of Bidens pilosa (Asteraceae) and Cymbopogon citratus (Poaceae) Aerial Parts on Hypertension Induced by a Chronic Salt and Alcohol Consumption on the Rats

High blood pressure (HBP) is currently one of the main risk factors for cardiovascular and kidney diseases. Nowadays, populations make extensive use of alternative medicine for their health problems. Bidens pilosa (B. pilosa) and Cymbopogon citratus (C. citratus) are used individually in the traditional treatment of cardiovascular disorders. This study assessed the effects of the mixture of these two plants aqueous extract on HBP in rats. Male rats (42) were divided into 7 groups of 6 rats each. Normotensive rats received only distilled water and formed group 1. The other animals received ethanol + salt preceded by distilled water (10 mL/kg; group 2) and spironolactone (10 mg/kg; group 3); the aqueous extracts of the mixture (100 and 200 mg/kg; groups 4 and 5) isolated plants B. pilosa (200 mg/kg; group 6) and C. citratus (200 mg/kg; group 7). Animals were treated for 7 weeks during which water consumption and urine volume were assessed; then, hemodynamic parameters were recorded, and rats were sacrificed. Serum and some organs (liver, kidney, heart, and aorta) were used to evaluate biochemical parameters. Ingestion of ethanol + salt leads to a significant increase in urinary volume and water intake that were significantly prevented by the extracts from the mixture and isolated plants. Ethanol + salt solution significantly increased the blood pressure, heart rate, triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-chol), very-low-density lipoprotein cholesterol (VLDL-chol), atherogenic indices, liver and kidney function parameters, and malondialdehyde (MDA) levels. However, the levels of high-density lipoprotein cholesterol (HDL-chol), albumin, reduced glutathione (GSH), catalase, and superoxide dismutase (SOD) activity were significantly reduced. The extracts of the mixture and isolated plants significantly prevented all these variations with a more pronounced action for the lowest dose of the mixture on the lipid profile, oxidative stress, and kidney function. These observations confirm the beneficial effects of B. pilosa and C. citratus to manage hypertension.

Sodium and Health: Old Myths and a Controversy Based on Denial

Purpose of Review

The scientific consensus on which global health organizations base public health policies is that high sodium intake increases blood pressure (BP) in a linear fashion contributing to cardiovascular disease (CVD). A moderate reduction in sodium intake to 2000 mg per day helps ensure that BP remains at a healthy level to reduce the burden of CVD.

Recent Findings

Yet, since as long ago as 1988, and more recently in eight articles published in the European Heart Journal in 2020 and 2021, some researchers have propagated a myth that reducing sodium does not consistently reduce CVD but rather that lower sodium might increase the risk of CVD. These claims are not well-founded and support some food and beverage industry’s vested interests in the use of excessive amounts of salt to preserve food, enhance taste, and increase thirst. Nevertheless, some researchers, often with funding from the food industry, continue to publish such claims without addressing the numerous objections. This article analyzes the eight articles as a case study, summarizes misleading claims, their objections, and it offers possible reasons for such claims.

Summary

Our study calls upon journal editors to ensure that unfounded claims about sodium intake be rigorously challenged by independent reviewers before publication; to avoid editorial writers who have been co-authors with the subject paper’s authors; to require statements of conflict of interest; and to ensure that their pages are used only by those who seek to advance knowledge by engaging in the scientific method and its collegial pursuit. The public interest in the prevention and treatment of disease requires no less.

Association between urinary potassium excretion and blood pressure: A systematic review and meta-analysis of observational studies

Background

The evidence base regarding the association between urinary potassium and blood pressure (BP), or risk of hypertension, is inconsistent. Therefore, we sought to conduct a qualitative and quantitative literature review on the association between potassium excretion and BP.

Materials and Methods

Medline, Scopus, Web of Science, Science Direct, and Google Scholar were searched up to June 2020. All observational studies that reported BP and measured potassium excretion in overnight or 24-h urine samples were included. Correlation coefficients, mean urinary potassium excretion, and odds ratio (ORs) of hypertension were extracted from the included studies. There were no language or publication date restrictions.

Results

Overall, twelve observational studies, including 16,174 subjects, were identified for inclusion in the present meta-analysis, and 21 effect sizes were extracted. Pooled mean potassium excretion was 3.46 mmol/24 h higher in normotensive individuals compared with hypertensive subjects (95% confidence interval [CI]: 0.61, 6.31). High urinary potassium excretion was not associated with the risk of hypertension (OR: 0.95; 95% CI: 0.79, 1.13). The pooled correlation coefficient between BP and urinary potassium was not significant (ES: 0.01; 95% CI: -0.03, 0.05). However, a subgroup analysis by age indicated a significant positive correlation between urinary potassium and systolic BP in children (ES: 0.12; 95% CI: 0.04, 0.19).

Conclusion

24 h urinary potassium excretion was not correlated to BP and risk of hypertension. In contrast, mean urinary potassium excretion was higher in normotensive individuals compared with hypertensive counterparts. Future studies should focus on the association between different sources of dietary potassium and BP.

Cost-effectiveness analysis of population salt reduction interventions to prevent cardiovascular disease in Cameroon: mathematical modelling study

BACKGROUND

Reducing dietary sodium (salt) intake has been proposed as a population-wide strategy to reduce blood pressure and cardiovascular disease (CVD). The cost-effectiveness of such strategies has hitherto not been investigated in Cameroon.

METHODS

A multicohort multistate life table Markov model was used to evaluate the cost-effectiveness of three population salt reduction strategies: mass media campaign, school-based salt education programme and low-sodium salt substitute. A healthcare system perspective was considered and adults alive in 2016 were simulated over the life course. Outcomes were changes in disease incidence, mortality, health-adjusted life years (HALYs), healthcare costs and incremental cost-effectiveness ratios (ICERs) over the lifetime. Probabilistic sensitivity analysis was used to quantify uncertainty.

RESULTS

Over the life span of the cohort of adults alive in Cameroon in 2016, substantial numbers of new CVD events could be prevented, with over 10 000, 79 000 and 84 000 CVD deaths that could be averted from mass media, school education programme and salt substitute interventions, respectively. Population health gains over the lifetime were 46 700 HALYs, 348 800 HALYs and 368 400 HALYs for the mass media, school education programme and salt substitute interventions, respectively. ICERs showed that all interventions were dominant, with probabilities of being cost-saving of 84% for the school education programme, 89% for the mass media campaign and 99% for the low sodium salt substitute. Results were largely robust in sensitivity analysis.

CONCLUSION

All the salt reduction strategies evaluated were highly cost-effective with very high probabilities of being cost-saving. Salt reduction in Cameroon has the potential to save many lives and offers good value for money.

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.

Prevalence and determinants of blood pressure variability in pygmies of Southern region Cameroon

INTRODUCTION

The impact of urbanization and living conditions on the prevalence of hypertension in the Cameroonian population is poorly known.

AIM

To evaluate the prevalence and determinants of blood pressure (BP) in adult Pygmies and Bantus living in urban and rural areas of Southern Cameroon.

PARTICIPANTS AND METHODS

This was a cross-sectional comparative study of 406 adults (96 urban Bantus, 100 urban Pygmies, 111 rural Bantus and 99 tropical rainforest Pygmies with a traditional Pygmies way of life), recruited in Southern Cameroon (mean age 42 ± 17 years; 56.7% women). Sociodemographic, anthropometric and BP parameters were collected. Hypertension was defined as BP at least 140/90 mmHg and/or use of BP-lowering drug(s).

RESULTS

The age-standardized prevalence of hypertension in urban Bantus, rural Bantus, urban Pygmies and traditional Pygmies was 18.0, 13.5, 9.3 and 4.1%, respectively. Mean SBP and DBP differed significantly according to Bantu vs. Pygmy ethnicity, and urban vs. rural residency. After multiple adjustments, mean arterial pressure was significantly associated with age, BMI, Bantu ancestry and urban residency.

CONCLUSION

Bantu ethnicity and urban residency are significantly associated with high-BP among people from Southern Cameroon.

Associated Factors of Hypertension in Women and Men in Vietnam: A Cross-Sectional Study

Background: Hypertension is a direct cardiovascular disease risk. It causes a heavy burden on the healthcare system globally. We aim to assess hypertension occurrence and its associated factors among women and men in Vietnam. Methods: A cross-sectional study was conducted from January to February 2019 on 2203 community-dwelling women and men aged 18 years or above. Participants’ characteristics, comorbidity, behaviors, and physical measures were evaluated. Hypertension was classified as systolic/diastolic blood pressure ≥140/90 mmHg or using antihypertensive medication. We analyzed data using logistic regression models. Results: The prevalence of hypertension was 24.3% (20.9% in women, 29.1% in men). For women, older age (odds ratio, OR, 6.80–12.41; p < 0.001), income above the poverty line (OR, 0.64; p = 0.008), diabetes comorbid (OR, 2.98; p < 0.001), added salts consumption (OR, 1.80; p < 0.001), overweight/obesity (OR, 1.64; p = 0.005), abdominal obesity (OR, 2.07; p < 0.001) were associated with hypertension. For men, older age (OR, 2.67–5.92; p < 0.001), diabetes comorbid (OR, 2.25; p = 0.010), smoking (OR, 1.38; p = 0.046), and overweight/obesity (OR, 2.18; p < 0.001) were associated with hypertension. Conclusions: Hypertension is prevalent in Vietnamese people. The associated factors of hypertension are varied by gender.

Blood pressure and burden of hypertension in Cameroon, a microcosm of Africa: a systematic review and meta-analysis of population-based studies

OBJECTIVE

To estimate national and geography-based variations in blood pressure and burden of hypertension in Cameroon, generally called 'miniature Africa'.

METHODS

PubMed, Medline, EMBASE, CINHAL, Web of Science, Popline, Scopus and BDSP were searched through November 2018, for hypertension studies among Cameroonians aged at least 18 years. Hypertension was measured as SBP at least 140 mmHg or DBP at least 90 mmHg. Random-effects meta-analysis was used.

RESULTS

Twenty studies involving 46 491 participants met inclusion criteria. Overall hypertension prevalence was 30.9% [95% confidence interval (CI) 27.0-34.8]: 29.6% (24.1-35.1) and 32.1% (27.2-37.1) in 1994-2010 and 2011-2018, respectively. Of hypertensive participants, only 24.4% (18.9-30.0) - 31.6% (21.0-42.3) and 20.8% (14.0-27.7) in 1994-2010 and 2011-2018, respectively - were aware of their status, 15.1% (10.6-19.6) were taking antihypertensive medications and 8.8% (5.7-11.9) - 10.4% (7.5-13.3) and 8.3% (4.4-12.3) in 1994-2010 and 2011-2018, respectively - were controlled. Hypertension prevalence varied by sex: 34.3% (30.0-38.6) for men and 31.3% (26.5-36.1) for women; ethnicity: from 3.3% (0.4-6.2) among Pygmies to 56.6% (49.4-63.8) among Bamileke; urbanity: 25.4% (17.1-33.7) for rural and 31.4% (27.3-35.5) for urban dwellers; agroecological zone: from 35.1% (28.9-41.3) in Tropical highlands to 28% (20.1-35.9) in Guinea-Savannah; and subnational region: from 36.3% (27.8-44.9) in the West to 17.1% (9.9-44.2) in the South.

CONCLUSION

Cameroon's hypertension prevalence is high and increasing whereas awareness, treatment and control are low and declining. Emerging patterns call urgently for effective campaigns to raise hypertension awareness alongside strategies for hypertension prevention and BP control.