More than 15,000 adults followed for 25 Years
To investigate the relationship between serum sodium, hydration, and future heart failure, Dr. Dmitrieva and colleagues analyzed data from 15,792 adults in ARIC who were 44-66 years of age at study entry, with serum sodium levels from 135 to 146 mmol/L.
The participants were evaluated over five visits until they reached 70-90 years.
They were divided into four groups based on their average serum sodium concentrations at study visits one and two (conducted in the first 3 years): 135 -139.5 mmol/L, 140-141.5 mmol/L, 142-143.5 mmol/L, and 144-146 mmol/L.
The researchers determined the percentage of people in each group who developed HF and left ventricular hypertrophy at visit five (25 years after study enrollment).
Patients with higher serum sodium levels had a significantly higher risk for HF and left ventricular hypertrophy, after adjustment for other risk factors, including age, blood pressure, kidney function, blood cholesterol, blood glucose, body mass index, sex, and smoking status.
Every 1 mmol/L increase in serum sodium concentration in midlife was associated with 1.20 and 1.11 increased odds of developing left ventricular hypertrophy and HF, respectively, 25 years later.
“More studies are needed to find out what proportion of people with serum sodium 142 mmol/L and higher have this [serum sodium] level because they do not drink enough and will be able to reduce it by making sure they consistently drink 2 to 2.5 L per day,” said Dr. Dmitrieva.
“It is likely that for some people, other factors that are related to genetics or diseases affecting water-salt balance could be causing their increased serum sodium levels,” she speculated.
The study was funded by the Intramural Program of the National Heart, Lung, and Blood Institute. The authors and Dr. Joseph have no relevant financial disclosures.
A version of this article first appeared on Medscape.com.