TIME OF DAY EFFECT ON VOIDING PARAMETERS AS MEASURED BY STREAM DX: A HOME UROFLOMETRY DEVICE

INTRODUCTION AND OBJECTIVE: Stream Dx is a novel, home use uroflowmetry device that can be used to collect multiple uroflow measurements over several days in a patient’s home. Our objective was to assess whether voiding parameters changed depending on the hour of the day and if this data would be helpful in optimizing symptom relief with personalized recommendations. METHODS: Basic demographic data, voiding profiles, and International Prostate Symptom Scores were collected from April 2019 to September 2019 and analyzed retrospectively. In total, 132 patients met the inclusion criteria of using the device on at least two separate days and using the device at least three times. To estimate the association between voiding parameters (maximum volume, maximum flow, average flow, and number of voids) and the time of the day (7am-3pm, 3pm-11pm, and 11pm-7am), we used mixed effects models that adjusted for age. The coefficients and 95% Confidence Intervals were reported for the models. RESULTS: A total of 132 patients were enrolled in the study. The mean age was 66 years. On average, patients provided 7 days of voiding data. In total, 3,981 voids were analyzed (7am-3pm: 1329, 3pm-11pm: 1535, 11pm-7am: 1117 voids). Setting our reference time period to 7am-3pm, the time period between 11pm-7am was associated with higher maximum volume (Mean difference: 57.2mL, 95% CI: 49.6 to 54.7mL) and lower number of voids (Mean difference: -0.39, 95% CI -0.57 to -0.20). The time period of 3pm-11pm was associated with lower maximum flow (Mean difference: -0.36mL/s, 95% CI -0.67 to -0.06mL/s). CONCLUSIONS: Based on unique data provided by a home uroflowmetry device, late night/early morning voiding is associated with modestly higher volumes and slightly less frequency as compared to midday voiding. Late afternoon/evening voiding is associated with marginally lower flow rates. Using individual patient data may be helpful in optimally timing medication administration for symptom relief.Source of Funding: The National Institute of Diabetes and Digestive and Kidney Diseases. Award Number R44DK113878 and UL1TR002538.