Allowing patients with heart failure to drink as much fluid as they want had no negative effects on safety outcomes — including hospitalization and death — and prevented discomfort related to thirst, results of the FRESH-UP trial showed.
“The study questions the benefit of fluid restriction in patients with chronic heart failure,” said investigator Roland van Kimmenade, a cardiologist at Radboud University Medical Centre in Nijmegen, Netherlands.
In the multicenter, open-label trial, 504 patients were randomized to current advice, which is to drink less than 1500 mL of fluids per day, or to drink unlimited fluids. The FRESH-Up study fills a gap in the evidence, said van Kimmenade, who presented the study results at the American College of Cardiology (ACC) Scientific Session 2025 in Chicago. They were also published simultaneously in Nature Medicine.
Patients with heart failure have been advised to restrict fluids for decades, and the advice appears as recently as 2022 in US guidelines. However, fluid restriction is based on an intuitive idea that it would prevent congestion, he explained, and there is little evidence to support the advice.
FRESH-UP Trial
Safety outcomes were similar in the two groups, including death, hospitalization — all-cause and specifically for heart failure — use of intravenous loop diuretics, and acute kidney injury.
FRESH-UP investigators had hoped that the study would show improvements in quality of life for the patients assigned to unrestricted fluid intake. However, after 3 months of follow-up, patients who could drink as much as they wanted showed only a slight increase in quality of life, and those on restricted fluid showed only a slight decrease. Quality of life was measured with a standard survey, the Kansas City Cardiomyopathy Questionnaire, and the differences between the two groups were not statistically significant.
But “thirst distress,” measured with a standard questionnaire, was significantly higher in the restricted-fluid group. This was despite the fact that the average daily amount of fluids consumed was just under 1500 mL in the restricted-fluid group and 1764 mL in the unrestricted-fluid group, a difference of just over a cup.
The trial assessed patients with stable, rather than acute, heart failure, and New York Heart Association classes II and III disease, rather than patients with more severe class IV disease. Patients with hyponatremia were excluded from the study.
Who Will Benefit?
It’s unlikely that fluid restriction would change outcomes in patients with more severe heart failure, van Kimmenade said. Registries of patients with heart failure and a previous Canadian study of patients with heart failure and kidney disease have provided some evidence that patients with normal kidney function can clear water from the body.
“The study was really inspired by the patients,” said van Kimmenade. “Patients said to us, ‘You are giving us this advice, but I don’t like it. How is it helping me?'” Patients with heart failure didn’t like having to keep a record of what they drank during a day or having to decide whether they could have a cup of coffee with their spouse in the morning or a cup of tea with a friend in the afternoon.
Patients were even involved in funding the study, which was crowd sourced.
Patient quality of life is increasingly important, said Shelley Hall, MD, from the Baylor University Medical Center in Dallas, who is chair of the ACC Heart Failure and Transplant Council and an ACC-invited discussant.
“I was delighted to see the results of this trial. We have done such a good job with our interventions in heart failure that we need to start focussing on quality of life,” she said.
“Let’s be more compassionate to our patients and ourselves,” she added.
