Urinary sodium and potassium excretion, mortality, and cardiovascular events

• Main Authors: Avezum, A. (Author), Chifamba, J. (Author), Dagenais, G. (Author), Devanath, A. (Author), Diaz, R. (Author), Gulec, S. (Author), Ilow, R. (Author), Iqbal, R. (Author), Kabali, C. (Author), Kruger, L. (Author), Lanas, F. (Author), Lear, S.A (Author), Lee, S.F (Author), Liu, L. (Author), Lopez-Jaramillo, P. (Author), McQueen, M.J (Author), Mente, A. (Author), Mohammadifard, N. (Author), Mony, P. (Author), O'Donnell, M. (Author), Rangarajan, S. (Author), Rosengren, A. (Author), Teo, K. (Author), Wang, X. (Author), Yan, H. (Author), Yusoff, K. (Author), Yusuf, R. (Author), Yusuf, S. (Author), Yusufali, A.H (Author)
• Format: Article
• Language: English
• Published: Massachussetts Medical Society 2014
• Subjects: adult; Adult; aged; article; cardiovascular disease; Cardiovascular Diseases; cardiovascular mortality; cardiovascular risk; cerebrovascular accident; cohort analysis; controlled clinical trial; controlled study; diastolic blood pressure; diet; Diet; disease association; female; Female; follow up; Follow-Up Studies; heart failure; heart infarction; high risk population; human; Humans; hypertension; Linear Models; low risk population; male; Male; middle aged; Middle Aged; mortality; Mortality; multicenter study; outcome assessment; potassium; Potassium; potassium excretion; potassium urine level; priority journal; prospective study; risk assessment; sodium; Sodium; sodium excretion; sodium intake; sodium urine level; Sodium, Dietary; statistical model; systolic blood pressure; urinalysis; urine
• Online Access: View Fulltext in Publisher; View in Scopus

 BACKGROUND: The optimal range of sodium intake for cardiovascular health is controversial. METHODS: We obtained morning fasting urine samples from 101,945 persons in 17 countries and estimated 24-hour sodium and potassium excretion (used as a surrogate for intake). We examined the association between estimated urinary sodium and potassium excretion and the composite outcome of death and major cardiovascular events. RESULTS: The mean estimated sodium and potassium excretion was 4.93 g per day and 2.12 g per day, respectively. With a mean follow-up of 3.7 years, the composite outcome occurred in 3317 participants (3.3%). As compared with an estimated sodium excretion of 4.00 to 5.99 g per day (reference range), a higher estimated sodium excretion (≥7.00 g per day) was associated with an increased risk of the composite outcome (odds ratio, 1.15; 95% confidence interval [CI], 1.02 to 1.30), as well as increased risks of death and major cardiovascular events considered separately. The association between a high estimated sodium excretion and the composite outcome was strongest among participants with hypertension (P=0.02 for interaction), with an increased risk at an estimated sodium excretion of 6.00 g or more per day. As compared with the reference range, an estimated sodium excretion that was below 3.00 g per day was also associated with an increased risk of the composite outcome (odds ratio, 1.27; 95% CI, 1.12 to 1.44). As compared with an estimated potassium excretion that was less than 1.50 g per day, higher potassium excretion was associated with a reduced risk of the composite outcome. CONCLUSIONS: In this study in which sodium intake was estimated on the basis of measured urinary excretion, an estimated sodium intake between 3 g per day and 6 g per day was associated with a lower risk of death and cardiovascular events than was either a higher or lower estimated level of intake. As compared with an estimated potassium excretion that was less than 1.50 g per day, higher potassium excretion was associated with a lower risk of death and cardiovascular events. Copyright © 2014 Massachusetts Medical Society.