Higher spot urine sodium-to-potassium ratios are associated with increased stroke risk, according to a new study.
In an analysis of data from the Multi-Ethnic Study of Atherosclerosis (MESA), Michelle M. Averill, PhD, RD, of the University of Washington in Seattle, and colleagues found that individuals with a urinary sodium-to-potassium radio greater than 1 was associated with a significant 47% increased risk of stroke, after adjusting for sex, age, race, cardiovascular risk factors, sociodemographic characteristics, and potential confounders.
“The collection of spot urines is part of routine clinical care, and the measurement of these biomarkers is inexpensive, suggesting strong potential to use spot urines ratios in clinical care settings,” Dr Averill’s team concluded in a paper published in Stroke.
Additionally, they noted that an intermediate target (sodium-to-potassium ratios below 1) “is attractive for future public health interventions, and our data continues to provide evidence that sodium and potassium are linked to cardiovascular health.”
MESA is a prospective cohort study of 6814 adults from 4 ethnic groups: European-, African-, Asian-, and Hispanic-American. The cohort had an average follow-up of 11.7 years. Dr Averill and her collaborators focused on 6705 participants with complete data at baseline. The mean age of these individuals was 61.2 years.
Only 39% of MESA participants had a urinary sodium-to-potassium ratio of 1 or less. Of the 236 strokes the occurred, only 74 occurred in these patients.
“The sodium-to-potassium ratio of 1 was selected because it was both easy to interpret in a clinical setting and was significantly associated with stroke,” the investigators noted.
Averill MM, Young RL, Wood AC, et al. Spot urine sodium-to-potassium ratio is a predictor of stroke. Stroke. 2019;50:321-327.