The prevalence of primary monosymptomatic nocturnal enuresis (PMNE) varies from 1.6% to 15%. Although treatment with enuretic alarms has been used for a long period of time, there are many disadvantages, including the necessity for long-term use and the high percentage of children who are resistant to such therapy. We hypothesized that more intense use of the alarm system would accelerate the process of forming the conditioned response to awakening, caused by the desire to urinate and, probably, increase the percentage of patients with positive results. Increased fluid intake will cause more frequent awakenings, so the use of alarm system will be more intense (Figure).
To study the effect of increased fluid intake, prior to going to bed, on the efficacy of alarm therapy.
The treatment group consisted of 294 children (178 boys) average age: 11.3 (9.1-11.9) years. All participants completed an overactive bladder questionnaire (OAB-q) and a bladder diary, and underwent uroflowmetry, blood and urine testing. Group A (n = 141, mean age 10.9 (9.1-11.6) years), used the alarm system traditionally (Wet Stop/BYE-WET, USA). Group В (n = 153, mean age 11.5 (9.3-11.9) years) drank either water or any other transparent non-colored fluid (any table mineral water with mineralization of less than 1 g per dm³) once immediately prior to sleep at a volume of 4-5 ml/kg of body weight. The effectiveness of therapy was assessed by the change in frequency of urination episodes during sleep per week, episodes of spontaneous awakenings, caused by the desire to urinate per week. Data were analyzed using JMP SAS Statistical Discovery 8.0.2. Wilcoxon criterion was used for comparison of results between groups; correlation of changes in groups was analyzed using the Spearman coefficient.
Complete resolution of NE, 2 weeks after the end of alarm therapy, was found in 34 patients (24%) in Group A and 59 (39%) in Group B. This difference was statistically significant with a confidence level of 95%.
Having searched the publication databases, including PubMed and Scopus, we failed to find any publication presenting evidence or recommendations on the ideal management of fluid intake in patients with PMNE. Although a limitation of fluid intake is commonly recommended, there is no evidence showing an increase in dry night frequency when such fluid restriction is used as monotherapy. In contrast, our study has shown an improvement in outcome when an increased fluid intake is used in combination with enuretic alarm therapy.
We were able to prove that increased fluid intake improved the efficiency of alarm therapy intervention during the treatment of PMNE in children.