Increased fluid intake has minimal effect on male bladder function

January 4, 2007

Increased water intake may improve some aspects of bladder function in older men, but the effects are too small to be clinically relevant, according to a study by Dutch researchers.

Increased water intake may improve some aspects of bladder function in older men, but the effects are too small to be clinically relevant, according to a study by Dutch researchers.

A total of 141 men, 55 to 75 years of age, with moderate lower urinary tract symptoms participated in the randomized, placebo-controlled trial (Urology 2006; 68:1031-6). The experimental group drank an additional 1.5 liters of water daily, and the control group consumed one tablespoon of placebo syrup daily.

After 6 months, the team evaluated bladder contractility, voided volumes, and the severity of lower urinary tract symptoms. Increases in water consumption were measured.

Water consumption in the intervention group increased by 359 mL (95% confidence interval: 171-548) per 24 hours compared with the control group. At 6 months, no statistically significant effect was found in the maximum flow rate (0.9 mL/s, 95% CI: −0.4-2.2) of the intervention group compared with that of the placebo group. A statistically significant effect was found for bladder pressure (20 cm H2O, 95% CI: 6-34) and bladder wall stress (1.9 N/cm2, 95% CI: 6-34). In addition, the experimental group had greater maximum (44 mL, 95% CI: −1-90) and average (26 mL, 95% CI: 1-51) voided volumes per urination.

The subjective effect parameters improved in both groups, but no statistically significant differences were found between the two groups, the authors reported.