Fluid intake reminder system helps patients with kidney stones increase urine volume

The use of mini sipIT, a reminder system that includes a connected water bottle and a mobile app, was shown to be feasible in providing fluid intake feedback to increase 24-hour urine volume among patients with kidney stones.¹

“This study helps establish the feasibility of using behavioral intervention technologies to provide real-time fluid intake feedback to improve 24-hour urine volumes as a strategy for stone prevention," says Necole M. Streeper, MD.

The study enrolled patients with a history of nephrolithiasis and a urine volume of less than 2 L per day. In total, 26 patients completed the entire trial for a completion rate of 74%. Among patients who completed the entire trial, 77% were female, and the median age was 50.4 years. At the start of the trial, 85% of patients had been told to increase their fluid intake to prevent recurrent stones, but 46% did not have a plan to meet the daily goal of 2.5 to 3.0 L/day, and only one third of patients knew the fluid intake goal.

The mini sipIT behavioral intervention consisted of a 1-month period in which participants received text message reminders via their smartphone when their fluid intake was insufficient, as determined with a H2OPal connected water bottle. Fluid-intake could be tracked via the water bottle or patients could manually enter their data.

The investigators measured patients’ perceptions of drinking behavior, intervention acceptability, and 24-hour urine volumes at baseline and at the end of the 1-month trial. Data for both times were collected on the same day of the week. The primary outcome was 24-hour urine volume.

During the 1-month time period, over 90% of the participants used the bottle or app daily. At the end of the intervention, 85% of patients indicted that they believed the reminder system helped increase their fluid intake, and 65% indicated that they believed it helped them reach their fluid intake goals over the 1-month period. Most patients (88%) indicated that the tool was “easy to use,” although 8% stated that it was “unnecessarily complex.”

Regarding urine volumes, the data showed a significant increase in 24-hour urine volume over the intervention period, with an average of 2006.5 ± 980.8 mL at baseline compared with 1352.7 ± 449.9 mL after 1 month (t (25) = 3.66, P =.001, g = .78). The average 24-hour urine volumes were similar at baseline (M = 1285.4mg/day, SD = 450/1) and at the end of the 1-month period (M = 1283.4 mg/day, SD = 499.9).

In total, 73% of patients showed an increase in 24-hour urine volume from baseline to the end of the trial period. A urine volume of greater than 2 L was reached by 42% of participants by the end of the study period.

“This study helps establish the feasibility of using behavioral intervention technologies to provide real-time fluid intake feedback to improve 24-hour urine volumes as a strategy for stone prevention. Future studies will be necessary to determine efficacy, habit formation, and whether high fluid intake persists once the intervention or digital tools are discontinued,” concluded lead author Necole M. Streeper, MD, in correspondence with Urology Times. Streeper is an associate professor of urology at Penn State Health in Hershey, Pennsylvania.

Reference

1. Streeper NM, Fairbourn JD, Marks J, Thomaz E, Ram N, Conroy DE. Feasibility of mini sipIT behavioral intervention to increase urine volume in patients with kidney stones. Urology. Published online June 29, 2023. Accessed July 26, 2023. doi:10.1016/j.urology.2023.06.019