Urinary sodium excretion and the risk of CVD: a community-based cohort study in Taiwan

Abstract

Urinary sodium excretion is a potential risk factor for cardiovascular diseases (CVD). However, the underlying biological mechanisms and effects of salt sensitivity are unclear. The purpose of this study was to characterize the relative contribution of biological factors to the sodium-CVD association. A total of 2112 participants were enrolled in this study. Structured questionnaires and blood and urine samples were obtained. Twenty-four-hour sodium excretion was estimated using a single overnight urine sample. Hypertension, metabolic syndrome, and overweight status were considered to indicate salt sensitivity. Cox proportional hazard models were used to investigate the effects of salt sensitivity on urinary sodium excretion and CVD risk. The traditional mediation approach was used to calculate the proportion of mediation. The mean age (standard deviation) of the 2112 participants was 54.5 (12.2) years, and they were followed up for a mean of 14.1 [8.1] years. Compared with those in the lowest quartile, the highest baseline urinary sodium excretion (>4.2g/24 hours) was associated with a 43% higher CVD risk (hazard ratio, 1.43; 95% confidence interval, 1.02-1.99). Participants with high urinary sodium excretion, hypertension, or metabolic syndrome had a significantly high risk of CVD. The carotid intima-media thickness had the largest mediating effect (accounting for 35% of the sodium-CVD association), followed by systolic blood pressure (33%), left ventricular mass (28%), and diastolic blood pressure (14%). Higher urinary sodium excretion increased the risk of CVD, which was explained largely by carotid media-thickness and systolic blood pressure.

Sodium intake and the risk of various types of cardiovascular diseases: a Mendelian randomization study

“…Furthermore, an MR study investigating the impact of urinary sodium on cardiovascular risk factors, ischemic stroke, and heart failure (HF) demonstrated that higher levels of urinary sodium were associated with an elevated risk of both HF and global ischemic stroke ( 34 ). Consistent with our own findings, a cohort study conducted in Taiwan revealed a significant association between increased urine sodium excretion and a higher risk of CVD, particularly stroke ( 35 ). However, a Finnish cohort study reported contrasting results, finding no significant correlation between urinary sodium levels and major adverse coronary events in men with HF ( 36 ).…”