Too Little Salt May Worsen Heart Failure Prognosis - Here's Why

A new study showed that restricting salt intake may actually have a negative impact on the prognosis for patients dealing with a common form of heart failure.

BMJ Journals published the study conducted by Chinese researchers on its heart website Monday (July 18), which suggests that, despite being recommended in heart failure guidelines, overly strict measures may actually worsen prognosis, especially among patients with preserved ejection fraction, which accounts for half of all cases.

"Over-strict dietary salt intake restriction could harm patients with [heart failure with preserved ejection fraction] and is associated with worse prognosis," the journal entry stated.

"Physicians should reconsider giving this advice to patients," the journal added.

Preserved ejection fraction results in a patient's left ventricle being unable to properly fill with blood and, therefore, pumps less out into the body.

Salt restriction is commonly recommended in heart failure guidelines, but researchers said the optimal restriction range and its effect on patients is unclear as heart failure patients are typically excluded from studies relevant to the measure.

Researchers used secondary analysis of data among 1,713 people age 50 and older who participated in TOPCAT, a placebo-controlled study used to determine whether the drug spironolactone could treat symptomatic heart failure with preserved ejection.

During the study, participants were asked how much salt they typically added to their meals, which was scored as 0 for no salt; 1 for 1/8 teaspoon; 2 for 1/4 teaspoon and 3 for 1/2 teaspoon or more.

Researchers then monitored the participants' health for an average of three years, which included death or hospitalization in relation to cardiovascular disease.

The study showed that nearly half the participants said they hadn't added salt to meals, which was significantly more than those who scored above zero for common salt intake.

Scientists did, however, acknowledge that the cooking salt scores were self-reported and shouldn't rule out restrictions for salt intake among people with poorer health conditions.

You can read the full study on BMJ.com here.