Predictors of outcome in children and adolescents with overactive bladder treated with parasacral transcutaneous electrical nerve stimulation.
BACKGROUND
Parasacral transcutaneous electrical nerve stimulation (TENS) has emerged as an effective treatment for overactive bladder (OAB) in view of its high success rates in improving lower urinary tract symptoms and constipation, with no direct side effects. However, the clinical characteristics associated with the outcomes remain to be established.


OBJECTIVE
The aim of this study was to evaluate potential predictors of outcome in children with OAB treated using parasacral TENS.


STUDY DESIGN
This was a prospective study of children with symptoms of isolated OAB, enrolled consecutively to the study and treated with parasacral TENS (figure). Isolated OAB was defined as the presence of urinary urgency with no signs of dysfunctional voiding. The symptoms were considered completely resolved when a patient's parents/guardians or the patients themselves reported a 100% improvement. Parasacral TENS was performed twice weekly for a total of 20 sessions of 20 min each at 10 Hz. The potential predictive factors evaluated were: sex, age, daytime incontinence, nocturia, a prior history of urinary tract infection, the presence of nocturnal enuresis, constipation and holding maneuvers.


RESULTS
Eighty-three patients with a mean age of 7.8 ± 2.8 years were included in the study. Complete resolution of symptoms was achieved in 47 (56.6%). Following parasacral TENS treatment, a significant response was reported in 96.4% of cases. Of the 55 patients with nocturnal enuresis, partial resolution was achieved in 30 cases (54.5%), with a statistically significant association between nocturnal enuresis and the patient's response to treatment (p < 0.004; OR = 4.4, 95% CI 1.5-12.5). No other factor was associated with response to treatment.


DISCUSSION
To the best of our knowledge, this association between nocturnal enuresis and failure to respond to parasacral TENS treatment for lower urinary tract dysfunction has not previously been reported. The identification of factors capable of predicting therapeutic failure may allow professionals to select those specific patients who would benefit from a multimodal approach in the treatment of this pathology, which has such a significant impact on the quality of life of affected patients.


CONCLUSIONS
Nocturnal enuresis was the only symptom associated with a poor outcome following parasacral TENS treatment in children with OAB.