High fluid intake helps reduce BP in children

Drinking lots of fluids can lower blood pressure (BP) in children by increasing renal sodium excretion, according to a recent study.

“We speculate that this simple, highly acceptable, inexpensive, and harmless measure might have a role in preventing and/or minimizing the epidemics of hypertension and of its related morbidities both in children and in adults,” the investigators said.

The SPA Project, a multicentre, observational, cross-sectional cohort study, was carried out to explore the working hypothesis that an increased fluid intake could improve renal sodium handling towards BP reduction. A total of 339 healthy children (aged 5–8 years, 51.6 percent boys) participated in the study.

The investigators obtained sodium and fluid intake through urinary sodium and creatinine from multiple samples in different days and characterized these into lower/higher sodium and lower/higher fluid intake. Both systolic (SBP) and diastolic BP (DBP) were used as measurement outcomes.

Of the participants included, only 223 were fit for analysis. Among children with higher sodium intake, those with increased fluid intake had a significantly lower BP (both SBP and DBP) than those with lower fluid intake (SBP: 86.0 vs 90.0 mm Hg; p=0.014; DBP: 53.8 vs 58.6 mm Hg; p<0.0001).

“Sodium intake is known to contribute to the development of hypertension; thus, intake reduction is a cornerstone in the prevention and management of hypertension,” the investigators said. “The increase in renal sodium excretion might represent a further potential preventive or therapeutic opportunity.”