We recently completed:  

Jonathan Rabinowitz, Mahmoud Darawshi, Nuriel Burak, Manfred Boehm, Natalia I Dmitrieva, Risk of hypertension and heart failure linked to high-normal serum sodium and tonicity in general healthcare electronic medical records, European Journal of Preventive Cardiology, 2025;, zwaf232, https://doi.org/10.1093/eurjpc/zwaf232

Based on almost a half million electronic medical records from Israels  Leumit Healthcare Services, with 20 years of follow-up, we found that healthy persons when the data collection began who had high normal sodium values (140-146) had a higher risk of developing hypertension as much as 29% increased risk and risk for heart failure reaching 20%.  Almost 40% of the current healthy members of  Leumit Healthcare Services have sodium values associated with increased risk for hypertension and Heart failure. 

The take home message from this study is that electronic medical records could be used to identify individuals at increased risk of hypertension and heart failure based on serum sodium levels, suggesting that preventative interventions focused on hydration could be implemented within primary care settings.