Through the zipper or pants down: Does it change uroflowmetry parameters in healthy males?

Objective

To evaluate if voiding through the zipper or voiding pants down would make any difference with regard to uroflowmetry parameters and postvoiding residual urine (PVR) volumes in healthy males with no lower urinary tract symptoms (LUTS).

Methods

Healthy males over 18 years of age with no LUTS were prospectively evaluated using a uroflowmetry test. Each individual was asked to void through the zipper (group 1) and pants down (group 2) at different times. The uroflowmetry test was repeated if the voided volume did not exceed 150 mL. Uroflowmetry results such as voided volume, maximum flow rate (Qmax), average flow rate (Qave), and duration of voiding were noted. PVR volume was assessed using ultrasonography. Electromyography was not used. Data are shown as mean ± standard deviation. For statistical analysis, a paired t test was used to analyze parametric parameters.

Results

A total of 44 males were enrolled. The median age of the individuals was 24 (range 18-44 years). There were no statistically significant differences between the two measurements in terms of voided volume (307 ± 121 mL vs 325 ± 145 mL, P = .365) and duration of voiding (25 ± 11 s vs 23.8 ± 11.6 s, P = .526). However, there were statistically significant differences in Qmax (26.6 ± 6.7 mL/s vs 30.0 ± 8.2 mL/s, P = .001), Qave (14.4 ± 3.6 mL/s vs 16.2 ± 5.1 mL/s, P = .009), and PVR volumes (23.9 ± 19.4 mL vs 3.9 ± 9.6 mL, P = .0001).

Conclusion

Voiding pants down shows higher flow rates and lower PVR than voiding through the zipper in individuals with no LUTS. Future studies with a larger number of individuals (including those with LUTS) and a broader age range cohort are required for solid conclusions.