Background Nocturnal enuresis is a prevalent condition among children, impacting approximately 15-20 % of 5-year-olds and around 7 % of 7-year-olds. Despite numerous studies investigating enuresis alarm therapy, the precise mechanism of the alarm's efficacy remains uncertain. Additionally, it remains unclear whether enuresis alarm therapy induces nocturia. The aim of this study was to examine the feasibility of predicting the treatment duration, to explore whether alarm therapy causes a transition from enuresis episodes to nocturia, and to investigate if the alarm activates progressively later in the night during the treatment period.
Methods Starting in 2016, caregivers of children with nocturnal enuresis undergoing alarm treatment at Aalborg University Hospital have been requested to document what time the alarms went off and instances of nocturia throughout the entire treatment period using a standardized form provided by the department.These data were used for a retrospective analysis of children aged 5-15 who fully responded to alarm therapy at the Department of Pediatric and Adolescent Medicine, Aalborg University Hospital, from January 1, 2016, to October 1, 2023. The families completed a bladder diary covering two days and seven nights before initiating the alarm therapy. This diary was utilized to calculate maximum voided volume (MVV) and nocturnal urine production (NUP) adjusted for age. Data on family history of nocturnal enuresis and type of enuresis (monosymptomatic/non-monosymptomatic) was extracted from the patient’s electronic medical record.The quantity of alarms and episodes of nocturia, along with their respective timing, was obtained from the completed forms.
Results A total of 142 children were included. Male to female ratio of the participants was 1.6:1. Median age at time of diagnosis was 8.1 (7.3; 9.7). First degree relatives with enuresis were identified in 45 % of the participants, and 65 % had monosymptomatic enuresis.A small bladder capacity was observed in 44.4% of the children, 3.5% exhibited only polyuria, 2.8% had both a small bladder and polyuria, and 49.3% had neither condition. Median duration of treatment was 44.0 days (32.0; 59.2). There was no difference in the time to successful treatment based on gender, the underlying pathophysiology or whether the enuresis was monosymptomatic.We observed an increase of 7.2 minutes per week in the time between bedtime and the first alarm during the first six weeks of treatment (p=0.002).Episodes of nycturia were not increased in the last week of treatment compared to first treatment week (RR 0.86, 95 % CI 0.66; 1.14).
Conclusions In children with nocturnal enuresis who respond positively to alarm therapy, most achieve complete success within six weeks of treatment. Enuresis episodes occur progressively later
in the night. This, along with the observation that alarm therapy does not seem to cause nocturia, supports the hypothesis that the mechanism of action for alarm therapy is an increase in functional bladder capacity (FBC).
