Hooton TM, et al. - In this randomized clinical trial, researchers evaluated the effectiveness of higher daily intakes of water on the frequency of recurrent cystitis in premenopausal women. According to findings, increased water consumption is an effective antimicrobial-sparing strategy to prevent recurrent cystitis in premenopausal women who drink low volumes of fluid daily and are at high risk for recurrence.

Methods

• Researchers of this randomized, open-label, controlled, 12-month trial at a clinical research center (years 2013-2016) recruited a total of 163 healthy women with recurrent cystitis (≥ 3 episodes in past year) who drank < 1.5 L of fluid per day.
• Of these women, 23 were excluded and 140 were randomized to either the water (directed to drink 1.5 L of water daily) or control group (directed to drink no fluids in addition to their usual fluid intake) for 12 months.
• Evaluations of daily fluid intake, urinary hydration and symptoms of cystitis were carried out during baseline visits, 6- and 12-month visits, and monthly phone calls.
• Frequency of recurrent cystitis over 12 months was primary outcome measure.
• Number of antimicrobial regimens used, mean time interval between cystitis episodes, and 24-hour urinary hydration measurements were included secondary outcomes.

Results

• Mean (SD) participant age was 35.7 (8.4) years, and the mean (SD) number of cystitis episodes in the previous year was 3.3 (0.6).
• The mean number of cystitis episodes was 1.7 in the water group vs 3.2 in the control group during the 12-month study period, with a difference in means of 1.5.
• In total, there were 327 episodes of cystitis: 111 in the water group and 216 in the control group.
• The mean number of antimicrobial regimens used to treat cystitis episodes was 1.9 and 3.6 in the water and control groups, respectively, with a mean difference of 1.7.
• The mean time interval between cystitis episodes was 142.8 and 84.4 days, respectively, with a mean difference of 58.4.
• Between baseline and 12 months, water group participants had increased mean urine volume and voids and decreased osmolality of urine.