Low sodium, high potassium diet may benefit patients with SLE

Patients with systemic lupus erythematosus had lower 24-hour urinary concentrations of potassium and a higher urinary ratio of sodium to potassium compared with healthy controls, suggesting the alteration of dietary intake could reduce the risk of hypertension, according to researchers at Vanderbilt University.

Investigators collected morning urinary specimens from 178 patients with systemic lupus erythematosus (SLE) and 86 healthy individuals matched for age, sex and race for analysis of potassium and sodium content. Patients with SLE had a mean age 40.9 years. Women made up 88% of the study and 68% of study participants were white. Hypertension was present in 44% of patients with SLE and in 19% of control participants, while 36% and 12%, respectively, received antihypertensive medication.

Investigators used the Kawasaki’s formula, which includes age, sex, height, weight and urinary creatinine variables, to estimate 24-hour urine concentrations of sodium and potassium. They also measured blood pressure at two resting intervals and averaged these measures.

Investigators found the estimated 24-hour urinary sodium excretion was similar between patients and control participants, but discovered a significantly lower 24-hour excretion of potassium in patients with SLE. A higher urinary ratio of sodium to potassium was observed in patients with SLE, and was associated with higher systolic and diastolic blood pressure, regardless of the use of antihypertensive medication. This association persisted after investigators adjusted findings for age, sex and race. They found no associations between 24-hour urinary sodium or potassium levels and systolic or diastolic blood pressure in control participants. - by Shirley Pulawski

Reference:

Barnado A, et al. Paper #1807. Presented at: American College of Rheumatology Annual Meeting; Nov. 7-11, 2015; San Francisco.

Disclosure: The researchers report no relevant financial disclosures.