The Hyponatremia Epidemic: A Frontier Too Far?

Salt restriction induced hyponatremia in hypertensive patients in Rwanda: A case control study

BACKGROUND

Salt restriction is a fundamental principle in the non-pharmacological management of hypertension. The World Health Organization recommends a daily sodium intake of less than 2 g/day. In East African countries, particularly Rwanda, there is a known prevalence of low sodium intake, with a mean sodium intake of 1.6 g/day. However, despite this dietary habit, the national protocol for treating hypertension, as well as common clinical practice, often fail to account for the low salt intake in Rwandan communities. Hypertensive patients are still frequently advised to reduce their salt intake, and in some cases, they are instructed to eliminate salt entirely.

OBJECTIVES

This study was designed to determine the association between salt restriction and hyponatremia in hypertensive patients.

METHODS

A case-control study was conducted over a period of 6 months at two tertiary hospitals in Rwanda, with hyponatremia as the outcome variable and salt restriction as the exposure variable. Age, gender, and use of diuretics were matched between the case and control groups. Serum sodium concentrations were measured, and participants were then categorized into groups. Questionnaires were used for interviews.

RESULTS

245 participants meeting the inclusion criteria were selected, with 110 (44.9%) classified as cases and 135 (55.1%) as controls. Among them, 159 (64.8%) participants were restricted from consuming salt, with 74 (46.5%) following a salt-free diet. The odds of developing hyponatremia were 9.90 (95% CI, p < 0.001) among salt-restricted participants.

CONCLUSION

There is a strong association between salt restriction and hyponatremia in hypertensive patients on treatment in this study.

Pressure ulcers in palliative ward patients: hyponatremia and low blood pressure as indicators of risk

BACKGROUND

Prevention strategies for pressure ulcer formation remain critical in patients with an advanced illness. We analyzed factors associated with the development of pressure ulcers in patients hospitalized in a palliative care ward setting.

PATIENTS AND METHODS

This study was a retrospective analysis of 329 consecutive patients with a mean age (± standard deviation) of 70.4±11.8 years (range: 30-96 years, median 70.0 years; 55.3% women), who were admitted to the Palliative Care Department between July 2012 and May 2014.

RESULTS

Patients were hospitalized for mean of 24.8±31.4 days (1-310 days, median 14 days). A total of 256 patients (77.8%) died in the ward and 73 patients (22.2%) were discharged. Two hundred and six patients (62.6%) did not develop pressure ulcers during their stay in the ward, 84 patients (25.5%) were admitted with pressure ulcers, and 39 patients (11.9%) developed pressure ulcers in the ward. Four factors assessed at admission appear to predict the development of pressure ulcers in the multivariate logistic regression model: Waterlow score (odds ratio [OR] =1.140, 95% confidence interval [CI] =1.057-1.229, P=0.001), transfer from other hospital wards (OR =2.938, 95% CI =1.339-6.448, P=0.007), hemoglobin level (OR =0.814, 95% CI =0.693-0.956, P=0.012), and systolic blood pressure (OR =0.976, 95% CI =0.955-0.997, P=0.023). Five other factors assessed during hospitalization appear to be associated with pressure ulcer development: mean evening body temperature (OR =3.830, 95% CI =1.729-8.486, P=0.001), mean Waterlow score (OR =1.194, 95% CI =1.092-1.306, P<0.001), the lowest recorded sodium concentration (OR =0.880, 95% CI =0.814-0.951, P=0.001), mean systolic blood pressure (OR =0.956, 95% CI =0.929-0.984, P=0.003), and the lowest recorded hemoglobin level (OR =0.803, 95% CI =0.672-0.960, P=0.016).

CONCLUSION

Hyponatremia and low blood pressure may contribute to the formation of pressure ulcers in patients with an advanced illness.