The impact of constipation on lower urinary tract function and treatment response in patients with non-monosymptomatic enuresis.

Purpose: The purpose of this study was to compare the differences in lower urinary tract function and treatment response between non-monosymptomatic nocturnal enuresis (NMNE) pediatric patients with and without constipation.

Method: We retrospectively analyzed pediatric patients diagnosed as NMNE from our enuresis database. Inclusion criteria were children aged 5 years or older with a follow-up duration of at least one month. Basic evaluation included the Rome IV questionnaire, Dysfunctional voiding score questionnaire (DVSS), two-day voiding diary, one-week enuresis diary and uroflowmetry with post-void residual (PVR) measurement. Constipation was defined as a Rome IV score of ≥ 2. We compared the results of evaluations and treatment response between groups with and without constipation.

Results: From July 2005 to December 2021, we enrolled 128 children who met the diagnostic criteria for NMNE. The median age was 7 years (interquartile range [IQR]: 6-9), and the median follow-up duration was 8.6 months (IQR: 3.5-15.6). NMNE patients with constipation had significantly higher scores on the daytime incontinence, holding maneuver, urgency, and total scores of the DVSS questionnaire. No significant differences were found between those with and without constipation in terms of daytime maximal voided volume and voiding frequency as recorded in the voiding diary. Although the group without constipation showed a relatively higher maximum flow rate, there was no significant difference observed in the PVR between the two groups. Patients in the constipation group exhibited a higher proportion requiring the combination of more medications for enuresis treatment. However, constipation did not affect the time to achieve partial or complete response in NMNE patients. The use of laxatives also did not affect the treatment response in the constipation group.

Conclusion: Constipation in NMNE patients is associated with increased severity of daytime lower urinary tract symptoms and requires more medications to achieve treatment response. However, with proper treatment, the time to partial or complete response is comparable to those without constipation.

Clinical Trial Number: Not applicable.