Effect of salt substitution on community-wide blood pressure and hypertension incidence

Patients' perceptions of self-management of high blood pressure in three low- and middle-income countries: findings from the BPMONITOR study

Hypertension is the leading risk factor for global disease burden. Self-management of high blood pressure (BP) through self-monitoring and self-titration of medications, has proved to be one successful and cost-effective tool to achieve better BP control in many high-income countries but not much is known about its potential in low- and middle-income countries (LMICs). We used semi-structured questionnaires and focus groups in three LMICs; Peru, Cameroon and Malawi to examine perceptions and attitudes of patients diagnosed with essential hypertension towards living with hypertension, BP measurement and treatment, patient-physician relationship and opinions about self-management of high blood pressure. Results in all three countries were comparable. Patients showed varied levels of health literacy related to hypertension. BP measurement habits were mostly affected by resources available and caregiver support. Treatment and adherence to it were primarily affected by cost. Most patients were welcoming of the idea of self-management but skeptical about the ability to do self-monitoring accurately and the safety involving self-titration of medications.

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.

Effects of extreme potassium stress on blood pressure and renal tubular sodium transport

We characterized mouse blood pressure and ion transport in the setting of commonly used rodent diets that drive K⁺ intake to the extremes of deficiency and excess. Male 129S2/Sv mice were fed either K⁺-deficient, control, high-K⁺ basic, or high-KCl diets for 10 days. Mice maintained on a K⁺-deficient diet exhibited no change in blood pressure, whereas K⁺-loaded mice developed an ~10-mmHg blood pressure increase. Following challenge with NaCl, K⁺-deficient mice developed a salt-sensitive 8 mmHg increase in blood pressure, whereas blood pressure was unchanged in mice fed high-K⁺ diets. Notably, 10 days of K⁺ depletion induced diabetes insipidus and upregulation of phosphorylated NaCl cotransporter, proximal Na⁺ transporters, and pendrin, likely contributing to the K⁺-deficient NaCl sensitivity. While the anionic content with high-K⁺ diets had distinct effects on transporter expression along the nephron, both K⁺ basic and KCl diets had a similar increase in blood pressure. The blood pressure elevation on high-K⁺ diets correlated with increased Na⁺-K⁺-2Cl^- cotransporter and γ-epithelial Na⁺ channel expression and increased urinary response to furosemide and amiloride. We conclude that the dietary K⁺ maneuvers used here did not recapitulate the inverse effects of K⁺ on blood pressure observed in human epidemiological studies. This may be due to the extreme degree of K⁺ stress, the low-Na⁺-to-K⁺ ratio, the duration of treatment, and the development of other coinciding events, such as diabetes insipidus. These factors must be taken into consideration when studying the physiological effects of dietary K⁺ loading and depletion.

Innovative Implementation Strategies for Hypertension Control in Low- and Middle-Income Countries: a Narrative Review

PURPOSE OF REVIEW

This review summarizes the most recent and innovative implementation strategies for hypertension control in low- and middle-income countries (LMICs).

RECENT FINDINGS

Implementation strategies from Latin America, Africa, and Asia were organized across three levels: community, health system, and policy/population. Multicomponent interventions involving task-shifting strategies, with or without mobile health tools, had the most supporting evidence, with policy or population-level interventions having the least, focused only on salt reduction with mixed results. More research is needed to better understand how context affects intervention implementation. There is an emerging evidence base for implementation strategies for hypertension control and CVD risk reduction in LMICs at the community and health system levels, but further research is needed to determine the most effective policy and population-level strategies. How to best account for local context in adapting and implementing these evidence-based interventions in LMICs still remains largely unknown. Accelerating the translation of this implementation research into policy and practice is imperative to improve health and save lives globally.