# Predictors of Long-Term Relapse in Primary Monosymptomatic Nocturnal Enuresis: A Retrospective Cohort Study

## TL;DR

Children with primary nighttime bedwetting who have lower bladder capacity based on a diary are more likely to relapse after treatment.

## Contribution

The study identifies diary-based bladder capacity as a stronger predictor of relapse than other clinical factors in children with primary nocturnal enuresis.

## Key findings

- A diary-based FBC/EBC ratio above 79% reliably indicates a low risk of long-term relapse.
- Children with reduced diary-based bladder capacity may benefit from closer monitoring or prolonged therapy.
- UFM-derived bladder capacity and other factors like age or treatment modality were not significant predictors of relapse.

## Abstract

What are the main findings?
Reduced functional bladder capacity (FBC/EBC ratio) based on the voiding diary was identified as the strongest predictor of long-term relapse in children with PMNE.Age, sex, family history, treatment modality (alarm, desmopressin, or combination therapy), and reduced UFM-derived bladder capacity showed no significant association with long-term relapse.

Reduced functional bladder capacity (FBC/EBC ratio) based on the voiding diary was identified as the strongest predictor of long-term relapse in children with PMNE.

Age, sex, family history, treatment modality (alarm, desmopressin, or combination therapy), and reduced UFM-derived bladder capacity showed no significant association with long-term relapse.

What are the implications of the main findings?
A diary-based FBC/EBC ratio above 79% reliably indicates a low risk of long-term relapse and may assist clinicians in planning individualized follow-up strategies.Children with reduced diary-based bladder capacity may benefit from closer monitoring, prolonged maintenance therapy, or earlier supportive interventions to reduce the likelihood of relapse.

A diary-based FBC/EBC ratio above 79% reliably indicates a low risk of long-term relapse and may assist clinicians in planning individualized follow-up strategies.

Children with reduced diary-based bladder capacity may benefit from closer monitoring, prolonged maintenance therapy, or earlier supportive interventions to reduce the likelihood of relapse.

Introduction: Nocturnal enuresis is defined as involuntary urination during sleep in children, particularly those aged 5 years or older. Primary monosymptomatic nocturnal enuresis (PMNE) involves nighttime wetting without daytime symptoms, and although factors like reduced bladder capacity, nocturnal polyuria, and impaired arousal contribute, predictors of long-term relapse remain uncertain. Methods: This retrospective cohort study included 227 children aged ≥5 years with strictly defined PMNE who achieved complete remission following a standardized 3-month treatment protocol (alarm therapy, desmopressin, or desmopressin plus oxybutynin). All children underwent ICCS-based assessment, including physical examination, urinalysis, ultrasonography, UFM, a 48 h frequency/volume (F/V) diary, and post-void residual measurement. One year after treatment discontinuation, patients were reassessed using a 14-day wet-night diary. Predictors of relapse were analyzed using comparative statistics. Result: At 1-year follow-up, 48.5% of children experienced relapse. Age, sex, treatment modality, family history, and baseline wet-night frequency were not associated with relapse (p > 0.05). Diary-based FBC was significantly higher than UFM-based capacity (p < 0.001). Reduced diary-based mean FBC/EBC ratios were significantly more common among relapsing children (p < 0.001), whereas UFM-derived ratios showed no significant difference (p = 0.052). ROC analysis demonstrated moderate discriminatory performance for diary-based FBC/EBC (AUC 0.671). A ratio > 79% predicted sustained remission with 83.6% specificity and a positive predictive value of 73.5%. Conclusions: Diary-derived bladder capacity is the strongest predictor of long-term relapse in PMNE and outperforms UFM-based assessment. A mean FBC/EBC ratio > 79% provides a clinically useful threshold for identifying children at low risk of recurrence. Those with reduced diary-based capacity may benefit from closer follow-up or extended maintenance therapy.