Dietary Sodium Restriction Effective Against Treatment-Resistant Hypertension

For patients with treatment-resistant hypertension (TRH), a condition associated with heightened cardiovascular risks, a new study suggests that a simple lifestyle modification could hold the key to better health. This study published in the BMC Nephrology examined the potential benefits of self-imposed dietary sodium restriction among TRH patients and its impact on blood pressure (BP).

TRH patients face an uphill battle as their hypertension often resists conventional treatments, increasing their vulnerability to heart-related issues. Lifestyle changes, such as sodium reduction, have long been recognized as a vital component of managing high blood pressure. This study sought to determine whether TRH patients could effectively implement dietary sodium restriction and assess its effects on BP.

The study enrolled fifteen TRH patients, including 11 males, with an average age of 59. They underwent a four-week intervention, with two weeks adhering to their usual diet and two weeks on a self-imposed sodium-restricted diet, complemented by sodium-free bread.

Following sodium restriction, urinary sodium excretion dropped significantly, from 186 mmol/24-h to 91 mmol/24-h. Notably, almost all patients experienced reduced sodium excretion. The impact on blood pressure was equally remarkable, with both nocturnal and 24-hour systolic BP showing significant reductions of 8 and 10 mmHg, respectively.

The study also delved into potential mechanisms at play. Nitric oxide (NOx) levels increased, while B-type natriuretic peptide (BNP) and extracellular water content decreased significantly. Notably, the change in NOx levels correlated with the change in 24-hour systolic BP, suggesting a potential role for NOx in the blood pressure-lowering effects of sodium restriction.

Interestingly, the study also explored erythrocyte sodium sensitivity as a predictor for the impact of sodium restriction on BP. Surprisingly, BP response did not appear to be related to sodium sensitivity, as examined by the salt blood test. This study highlights the feasibility and efficacy of self-imposed dietary sodium restriction among TRH patients. The significant reduction in BP, along with changes in biochemical markers like NOx and BNP, offers hope for improved TRH management. 

Source:

Hornstrup, B. G., Hoffmann-Petersen, N., Lauridsen, T. G., & Bech, J. N. (2023). Dietary sodium restriction reduces blood pressure in patients with treatment resistant hypertension. In BMC Nephrology (Vol. 24, Issue 1). Springer Science and Business Media LLC. https://doi.org/10.1186/s12882-023-03333-9