Reducing salt intake might harm heart failure patients, study claims

December 28, 2015 by Dennis Thompson, Healthday Reporter
But finding is preliminary and much more research needed to test hypothesis, experts say.

(HealthDay)—For decades, doctors have urged heart failure patients to slash their salt intake as a way to preserve their health.

But a new study suggests—but doesn't prove—that that advice may be harmful, potentially increasing a heart failure patient's risk of death or hospitalization.

Patients with moderate heart failure who stuck to a low-sodium diet were 85 percent more likely to die or require hospitalization for heart disease, when compared to similarly ill patients who didn't restrict their , the researchers found.

"The conventional wisdom has been that is bad for you," said lead researcher Dr. Rami Doukky, a cardiologist and associate professor at Rush University Medical Center in Chicago. "This study says, not so fast. Maybe we should take that, no pun intended, with a grain of salt."

However, Doukky and other cardiologists warned that the study findings are very preliminary and should not be interpreted by heart failure patients to mean that it's OK to reach for the salt shaker. Rigorous clinical trials are needed to further test the safety of this hypothesis, the experts said.

"The study is meant to be an eye-opener, that we need to investigate this matter more. We used to take it [salt consumption] for granted, and now it is time to address it with more definitive trials," Doukky said.

Physicians have long assumed that salt is bad for heart failure patients because the mineral causes the body to retain water and pull additional fluid into the blood vessels, Doukky explained.

Physiologically, the assumption makes sense, said Dr. Clyde Yancy, chief of cardiology at Northwestern University's Feinberg School of Medicine in Chicago.

Heart failure patients struggle with fluid retention because their heart beats too weakly to fight the force of gravity, allowing blood and water to build up in their lungs, feet, ankles and legs, according to the U.S. National Institutes of Health.

Salt also increases blood pressure by drawing water into the arteries and veins, according to the American Heart Association, and is a long-known risk factor for heart disease.

However, a handful of recent studies have called those long-held assumptions into question, suggesting that a low-sodium diet might actually be harmful to heart failure patients, Doukky said.

To put it to the test, Doukky and his colleagues gained access to data from a clinical trial that followed heart failure patients an average of three years and tracked their salt intake using a food questionnaire.

The researchers examined 833 patients from the study, including 130 patients who followed a sodium-restricted diet. They were matched against 130 patients who had no restrictions on salt intake.

About 42 percent of following a low-sodium diet wound up dying or hospitalized for heart problems, compared to 26 percent of patients with no salt restrictions, the researchers found.

"To our surprise, we found that patients who were sodium-restricted had worse outcomes than those who were taking sodium more liberally," he said.

The study findings were published online Dec. 28 in JACC: Heart Failure, a journal published by the American College of Cardiology.

Doukky theorized that cutting back on salt might throw a heart failure patient's fluid volumes out of whack, with potentially harmful consequences.

"The idea is sodium restriction leads to a contraction of the fluid volume in the body, and that turns on certain hormones which try to retain fluids in the body and may potentially accelerate the process," he said.

Yancy noted that the new findings also shouldn't be applied to healthy people without heart problems. Salt remains a leading risk factor for high , which can cause , heart attack and stroke.

Explore further: Electronic monitoring device may help lower salt intake

More information: For more on salt and heart health, visit the American Heart Association.

Related Stories

Electronic monitoring device may help lower salt intake

November 16, 2014
Using an electronic monitoring device may help heart failure patients and their families stick to a low-salt diet, according to research presented at the American Heart Association's Scientific Sessions 2014.

The result of eating too much salt can be measured in blood pressure

July 29, 2015
People who gradually increase the amount of salt in their diet and people who habitually eat a higher salt diet both face an increased risk of developing high blood pressure, according to a study published in the Journal ...

Thiazide may pose some risk for congestive heart failure patients

November 6, 2015
Thiazide, a popular diuretic for lowering high blood pressure, may not excrete salt as expected in patients with congestive heart failure and or dehydration and should be taken with caution, say researchers at the University ...

Mexico sees heart failure improvements with diet and exercise

November 21, 2015
Doctors in Mexico have shown the benefits of a healthy diet and exercise in patients with heart failure, in research presented at the Mexican Congress of Cardiology 2015.

Kidney patients may gain from less salt

January 31, 2014
(Medical Xpress)—Reducing salt consumption may help prolong the lives of patients with chronic kidney disease, a study from The University of Queensland study has found

Living better with heart failure by changing what you eat

September 24, 2013
Diet can dramatically lower hypertension and improve heart function in patients with a common type of heart failure, according to research presented at today's Heart Failure Society of America meeting in Orlando, Fla.

Recommended for you

Could aggressive blood pressure treatments lead to kidney damage?

July 18, 2017
Aggressive combination treatments for high blood pressure that are intended to protect the kidneys may actually be damaging the organs, new research from the University of Virginia School of Medicine suggests.

Quantifying effectiveness of treatment for irregular heartbeat

July 17, 2017
In a small proof-of-concept study, researchers at Johns Hopkins report a complex mathematical method to measure electrical communications within the heart can successfully predict the effectiveness of catheter ablation, the ...

Concerns over side effects of statins stopping stroke survivors taking medication

July 17, 2017
Negative media coverage of the side effects associated with taking statins, and patients' own experiences of taking the drugs, are among the reasons cited by stroke survivors and their carers for stopping taking potentially ...

Study discovers anticoagulant drugs are being prescribed against safety advice

July 17, 2017
A study by researchers at the University of Birmingham has shown that GPs are prescribing anticoagulants to patients with an irregular heartbeat against official safety advice.

Protein may protect against heart attack

July 14, 2017
DDK3 could be used as a new therapy to stop the build-up of fatty material inside the arteries

Heart study finds faulty link between biomarkers and clinical outcomes

July 14, 2017
Surrogate endpoints (biomarkers), which are routinely used in clinical research to test new drugs, should not be trusted as the ultimate measure to approve new health interventions in cardiovascular medicine, according to ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

Eikka
not rated yet Dec 29, 2015
Aren't the general sodium intake recommendations already at the low end of the spectrum of what would be physically healthy? As in, the commonly recommended amount of daily intake is actually the lowest amount before you risk hyponatremia, and subsisting on such a diet would actually cause you symptoms similiar to alzheimers.

I remember I did some reading on this a while back, but I can't remember what the actual numbers were.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.