— Meta-analysis finds that higher water consumption lowers risk.
by Parker Brown, Staff Writer, MedPage Today March 29, 2015
DALLAS — People with a high water intake significantly reduced their risk of developing kidney stones, according to a meta-analysis presented here.
Those who drank more water to achieve a urine volume of at least 2.0-2.5 L per day were at a lower risk of developing incident kidney stones in two randomized trials (risk ratio 0.40, 95% CI 0.20-0.79) and seven observational studies (RR 0.49, 95% CI 0.34-0.71), reported Wisit Cheungpasitporn, MD, of the Mayo Clinic in Rochester, Minn.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
People who drank a higher volume of water also were at a reduced risk for recurrent kidney stones in the randomized trials (RR 0.40, 95% CI 0.20-0.79) and the observational studies (RR 0.20, 95% CI 0.09-0.44), they stated in a poster presentation at the National Kidney Foundationopens in a new tab or window (NKF) spring clinical meeting.
The two trials had 269 individuals in them while there were more than 250,000 in the observational studies. Data on compliance and safety were limited; one trial reported that no participants withdrew because of symptoms.
“This analysis shows that drinking water is an effective way to cut one’s risk for developing kidney stones in half,” said Kerry Willis, PhDopens in a new tab or window, NKF chief scientific officer, in an accompanying press release. “Confirmation of reducing risk through improved hydration is an important finding.”
But high water intake is a “two-edged sword,” cautioned Rahul Dhawan, DOopens in a new tab or window, of the University of Southern California in Los Angeles, who was not associated with the study. Drinking too much water can lead to hyponatremia, altered mental states, confusion, and even seizures, he said.
He added that, similar to other medical guidelines, there’s no “one size fits all” approach to determining how much water a person needs. In a guideline graded as “weak,” the American Urological Association and the American College of Physicians recommended that with a sufficient water intake, a person should produce 2.0-2.5 L of urine per day to prevent kidney stones, Cheungpasitporn’s group wrote.
“But more important is to monitor the patient’s urine output and color,” said Dhawan, who added that it’s also important that the patient is aware of problems related to low water intake.
“Monitoring drinking water is just part of the problem — the other major problem is dietopens in a new tab or window,” he said. “The notion that drinking water will completely prevent kidney stones, that’s false. And we need other research to look at how kidney stones can be reduced.”
Cheungpasitporn agreed that more research is needed. “We have strong evidence to say who should drink more,” he told MedPage Today. “The next step is to come up with a model for this.”
Disclosures
Cheungpasitporn and co-authors disclosed no relevant relationships with industry.
Primary Source
National Kidney Foundation
Source Reference: opens in a new tab or windowCheungpasitporn W, et al “Treatment effect and safety of high fluid intake for the prevention of incident and recurrent kidney stones: A meta-analysis” NKF 2015.