Drinking sufficient water may help prevent HF

Having high serum sodium levels above 142 mmol/L — which is indicative of insufficient fluid intake — is associated with a greater risk of left ventricular hypertrophy (LVH) and heart failure (HF) in later life, according to the ARIC* study presented at ESC 2021 Congress.

“Our study suggests that maintaining good hydration can prevent or at least slow down the changes within the heart that lead to HF,” said lead author Dr Natalia Dmitrieva of the National Heart, Lung, and Blood Institute in Bethesda, Maryland, US.

Serum sodium levels is an indicator of the body hydration state — serum sodium concentration increases when people take in less fluid. This prompts the body to conserve water by activating the antidiuresis pathway and the renin-angiotensin-aldosterone system, which can contribute to the development of HF.

“It is natural to think that hydration and serum sodium should change day to day depending on how much we drink on each day. However, serum sodium concentration remains within a narrow range over long periods, which is likely related to habitual fluid consumption,” Dmitrieva explained.

Dmitrieva and colleagues followed 15,792 adults aged 44–66 years, who were enrolled in the ARIC study, for 25 years over five visits until they were aged 70–90 years. The participants were categorized into four groups (135–139.5, 140–141.5, 142–143.5, and 144–146 mmol/L) based on their average serum sodium concentration during the first two visits. [ESC 2021, abstract 84152]

With every 1 mmol/L increase in serum sodium concentration during midlife, the risk of developing LVH rose significantly by 20 percent (odds ratio (OR), 1.20; p<0.001) and the risk of HF by 11 percent (OR, 1.11; p=0.031) 25 years later. Both the associations remained significant after adjusting for potential risk factors such as age, gender, BMI, blood cholesterol and glucose levels, kidney function, and smoking status. 

The increases in the risk of LVH or HF were particularly prominent when participants reached older age of 70–90 years, and in particular with serum sodium levels falling within the higher two quartiles of 142–146 mmol/L.

“The results suggest that good hydration throughout life may decrease the risk of developing LVH and HF,” said Dmitrieva. “The findings indicate that we need to pay attention to the amount of fluid we consume every day and take action if we find that we drink too little.”

According to the researchers, the recommended daily fluid intake ranged from 1.6–2.1 L for women and 2–3 L for men. However, many people fail to meet even the minimum level of the daily requirement.

“In addition, our finding that serum sodium exceeding 142 mmol/L increases the risk of adverse effects in the heart may help to identify people who could benefit from an evaluation of their hydration level,” Dmitrieva pointed out.

“This sodium level is within the normal range and would not be labelled as abnormal in lab test results, but could be used by physicians during regular physical exams to identify people whose usual fluid intake should be assessed,” she suggested.

*ARIC: Atherosclerosis Risk in Communities