Two sessions of behavioral urotherapy for bowel and bladder dysfunction: does it get any better?
Key Words: Urination disorders/therapy, behavior therapy, nocturnal enuresis.
Pediatric bowel and bladder dysfunction is a result of paradoxical pelvic floor contraction during voiding and encompasses a wide spectrum of symptoms, including urinary incontinence, nocturnal enuresis, urgency, frequency, and constipation/fecal incontinence. Children with this condition contract the urethral sphincter during voiding, producing a decreased and often staccato or intermittent pattern of urinary flow during urethral sphincter and pelvic floor contraction (Chase, Austin, Hoebeke, & McKenna, 2010). Presenting symptoms include incontinence, urgency, frequency, and constipation (Farhat et al., 2000; Halachmi & Farhat, 2008; Kibar et al, 2007).
Although complex cases may require more aggressive therapies, such as biofeedback or medications, for most patients, it is appropriate to begin with conservative management, such as urotherapy, which is composed of behavioral modification training sessions directed at educating children regarding proper voiding practices, schedules, and pelvic floor relaxation techniques. Children with bowel and bladder dysfunction benefit from bladder emptying re-education, and initial emptying efficiency and post-void residual volumes significantly improve following both shorter outpatient and longer inpatient training regimens (Bachmann et al., 2008; Bower, Yew, Sit, & Yeung, 2006; Chase et al, 2010; Nelson, Cooper, Boyt, Hawtrey, & Austin, 2004). In some instances, biofeedback has been utilized as a successful adjunct to behavioral modification in improving symptoms in children with bowel and bladder dysfunction (de Jong et al, 2007; Kajbafzadeh et al, 2011; Vasconcelos et al, 2006).
Our initial management of pediatric bowel and bladder dysfunction relies on behavioral urotherapy prior to escalation of treatment. However, the ideal number of visits to achieve maximum effect from this modality alone has not been clearly identified.
Purpose of the Study
The goal of our study was to determine if there is an optimal length of behavioral modification urotherapy before a plateau in bowel and bladder dysfunction symptom improvement is reached and further training sessions are not beneficial or worthwhile.
We anticipated four outcomes.
* After a certain number of sessions, behavioral urotherapy would no longer improve symptomatology (i.e., that the difference in Dysfunctional Voiding Scale Scores [DVSS] would cease to show statistically significant improvement following each session).
* A more constipated state, as represented by the Bristol Stool Scale (BSS), would be correlated with more severe voiding symptoms.
* The proportion of patients with normal uroflow patterns would cease to improve after a number of sessions.
* Non-attendance would have a negative impact on the rate of bowel and bladder dysfunction improvement.
The answers to these research hypotheses may result in more appropriate allocation of resources by creating a standardized protocol involving a certain number of urotherapy sessions for children with bowel and bladder dysfunction. If patients fail to show the anticipated symptomatic improvement within the prescribed number of urotherapy sessions, they could then be considered for biofeedback or pharmacological intervention.
Voiding parameters, such as uroflow curves, initial emptying efficiency, and post-void residual volumes, have been shown to improve after just a half-day training session, results which were sustained at three months (Bower et al., 2006). A study wherein children with lower urinary tract conditions were randomized to either immediate or delayed behavioral treatment demonstrated the efficacy and durability of results, based on both DVSS and symptomatology, following a behavioral urotherapy regimen when compared to a control group (Golli, Megli, & Kenda, 2013). However, it is still unclear just how long one should pursue this conservative approach before advancing to more aggressive measures (Thom, Campigotto, Vemulakonda, Coplen, & Austin, 2012).
This study, approved by the University of California, San Diego Human Research Protections Program, was a correlational, comparative, and descriptive observational study of a single cohort of pediatric patients presenting for treatment at a comprehensive urotherapy clinic located in San Diego, a large metropolitan area of southern California, which provides multiprofessional urological services to the residents of San Diego and neighboring counties. The clinic is staffed by two nurse practitioners, highly experienced pediatric urologists, and includes a continence center designed to treat problems such as daytime and nocturnal enuresis.
The entire population of 368 children with bowel and bladder dysfunction seen in the pediatric urology clinic from 2009 and 2010 for behavioral urotherapy and attended at least one session was recruited. Those who attended a single session but did not follow up in our clinic were included and contacted by telephone for follow up at the end of the study.
Patients were seen in a behavioral urotherapy clinic by one of two nurse practitioners. In addition to measuring the study outcome variables, renal and bladder ultrasound, and kidney, ureters, and bladder (KUB) X-ray examinations were performed to assess for hydronephrosis or other abnormality and to assess stool burden.
Both patient and caregiver participated in an initial 60-minute session and received education. A plan of care was individualized for each child's needs, including behavioral modifications, such as timed interval voiding, proper toilet positioning, relaxation, and breathing techniques, to facilitate pelvic floor relaxation, and adjusting diet and water intake based on current stool appearance. Patients then attended up to six additional 30-minute follow-up appointments to review uroflow, DVSS, and other clinical data. Adjustments to the plan of care were made when indicated.
Visit reminders were mailed one month in advance of each consecutive appointment, and an automated phone message was performed 24 to 48 hours in advance of all appointments. Patients who did not present for second visits [non-attendance) were contacted by phone at the end of data collection for quality assurance of their care, as well as assessment of their DVSS.
Patient demographics, comorbidities (including attention deficit hyperactivity disorder [ADHD]), history of urinary tract infection, medications, and presence of VUR were collected at baseline. DVSS, BSS, and uroflow curve were determined both at baseline (immediately prior to the first intervention/training) and again at each subsequent visit.
Dysfunctional Voiding Scoring System
The DVSS is used to reflect severity of disease and monitor symptom management, providing a non-invasive method of monitoring patient compliance and results following therapy sessions (Bartkowski & Doubrava, 2004; Farhat et al, 2000; Upadhyay et al, 2003). The DVSS is well-recognized in the literature as a reliable indicator of symptomatology for children with lower urinary tract condi tions (Bartowski & Doubrava, 2004; Chase et al, 2010; Farhat et ah, 2000; Golli et al, 2013).
The DVSS consists of 10 items; nine of these items are assessed by age-appropriate questions for children and are scored on a Likert-type scale ranging from 0, indicating almost never, to 3, indicating almost every time. One item is for caregivers to answer regarding stressful events in the child's life; this item provides response options that include yes, scored with 3 points, or no, scored as 0 points. Responses are summed for a composite score representing the severity of the urinary symptoms. Possible scores range from 0 to 30, with higher scores indicating more severe symptoms, while lower scores indicate milder and/or lower frequency of symptoms. The cut-off score for diagnosis of dysfunctional voiding is 6 for girls and 9 for boys (Kibar & Gok, 2013).
Bristol Stool Scale (BSS)
The BSS is a visual scale used to assess the quality of recent stools. It has been found to be a reliable indicator of stool quality with greater than 80% intra-observer reliability among children rating their stools (Lane, Czyzewski, Chumpitazi, & Shulman, 2011). The scale has been validated in prior studies as a useful tool to monitor change in intestinal function, both in clinical practice and research settings (Lewis & Heaton, 1997). The BSS categories range from 1, representing hard stools and constipated state, to 7, representing entirely liquid and watery stool. Ideal stools are types 3 and 4, and especially type 4 because they are most likely to glide out without pain or discomfort.
Uroflowmetry is a reliable, noninvasive test of the dynamics of urinary flow, including maximum and average flow rate, voided volume, time of micturition, and pattern of the curve (Pridgeon, Harding, Newton, & Pickard, 2007). Uroflow curves are classified into three main categories: bell-shaped, staccato (intermittently forceful stream), and breadloaf/plateau (steady flow even with increased pressures) patterns. Bell-shaped curves are considered to be ideal shape for uroflow.
Post-treatment improvement in clinical symptoms has correlated well with improvement of uroflowmetry parameters and voiding curve patterns (Vesna, Milica, Marina, Andjelka, & Lidija, 2010). Uroflow curves were assessed at each visit by having patients void and measuring the velocity curve of the urinary stream throughout the void.
General Statistical Approach
Statistical analysis was performed using SPSS v17.0; statistical significance was set a priori at less than 0.05. Statistical testing included using median DVSS with paired testing (Wilcoxon Rank, with bonferroni correction for repeated testing, and Kendall's W tests). The relationship between initial DVSS and BSS type was determined using Spearman's correlation. Characteristics of patients returning for additional therapy were also compared to those who did not present for follow-up after the first visit using Chi-square and Mann-Whitney U testing.
Characteristics of the Sample
The population (N = 368) consisted of males [n = 140, 38%) and females (n = 228, 62%) ranging in age from 3.3 to 16.9 years [M = 7.9, SD = 3.2). Of these, 82 (22%) reported having had a recent or current UTI. Of the 231 screened, 62 patients (16.8%) had VUR at baseline, and 28 (7.6%) had hydronephrosis documented on renal ultrasound. While 12 (3.3%) patients had ADHD, only three (0.8%) reported taking medication for this condition. Table 1 displays results of the quantitative outcome measures data taken at each visit and summarizes the attrition over time in that with each subsequent visit fewer patients presented for continued follow up.
We sought to determine whether the DVSS continued to improve or reached a plateau following a certain number of behavioral modification sessions. As seen in Table 1, median DVSS markedly decreased after a single session from 11 to 6 (p < 0.001) and continued to show statistically significant improvement from the second to third visit (p = 0.045). However, there was no significant improvement from third to fourth visit (p = 1.000).
The relationship between initial BSS stool types and DVSS was considered. Patients with a lower BSS score (increased constipation) had a worse initial DVSS at baseline. With therapy, BSS showed significant improvement from a median of 2.7 at baseline, representing harder stool and a more constipated state, trending to normal values of 3.8 at visit 6 (p < 0.001).
Unfortunately, over 20% of the participants at each visit were unable to produce a sufficient volume of urine for uroflow studies to be assessed. For the remainder of patients whose urine volumes were sufficient to be analyzed and classified by shape, the change in uroflow patterns over time was not statistically significant (p = 0.513). However, the proportion of patients with normal (bell-shaped) curves improved from 82.5% at baseline to 90.2% at visits 2 and 3.
Despite making three phone calls and leaving messages, a large number of patients who attended the first session did not return for additional sessions and were counted as non-attenders. Of the 196 non-attending patients, we were able to contact 97 (49.5%) by telephone at the end of the study; 99 (50.5%) were lost to follow up.
Comparisons were made between attending and non attending patients. No differences in age, gender, baseline DVSS, or BSS type were noted between groups. When comparing patients who attended two or more sessions to non-attending patients, the latter were more likely to have had VUR at baseline. Non-attending patients improved more dramatically after a single training session than those who returned for a second visit (DVSS 3 vs. 6, respectively, p < 0.001). Further, 61% of the non-attending patients reported improved symptoms as their reason for lack of follow up while four (14.4%) reported that limited resources prevented them from returning for a second training session. Median length of time to contact via telephone in these non-attending patients was 425 days, suggesting durability of symptomatic improvement beyond one year, after even a single training session.
Discussion and Implications
It is evident that among this group, a single urotherapy session was effective in alleviating symptoms in children with bowel and bladder dysfunction. However, this improvement appears to level off by the third visit, confirming our suspicion that beyond a certain number of training sessions, one does not observe further symptomatic improvement.
We found a similar trend over the first few visits with increasing numbers of normal or bell-shaped uroflow curves consistent with the observed improvement in median DVSS, again highlighting the efficacy of even one or two urotherapy sessions in objectively improving symptoms.
BSS type showed a statistically significant correlation with DVSS and improved over subsequent visits. This relationship has been shown in other studies, and improvement of constipation has been shown to be related to spontaneous VUR resolution as well (Halachmi & Farhat, 2008; Kibar et al., 2007). Non-attending patients largely reported they did not return for repeated sessions because they were so much improved they did not feel the need for additional training.
Other studies have shown that treatment of bowel and bladder dysfunction positively impacts resolution of VUR and decreases the risk of UTI, and that absence of dysfunctional voiding is an independent predictor of VUR resolution (Colen et al., 2006; Silva, Diniz, Lima, Vergara, & Oliveira, 2006). Because 30% of our patients did not have the presence/absence of VUR noted, we were unable to evaluate this effect.
Data on UTIs was not collected at every single visit, and a recall bias in collecting information about the history of UTIs exists. This incomplete registration of patients with comorbidities at baseline, combined with the attrition of patients after a couple sessions, prevents statistical significance to be reached in secondary analyses.
Additionally, while we could have used more sophisticated testing and questionnaires to assess whether our patients had ADHD, we simply asked the caretaker about the child's medical history; thus, we are hesitant to attempt any extensive analysis evaluating the effect of ADHD on improvement of dysfunctional voiding symptoms.
Other limitations of our study include the use of the DVSS system to reflect symptom severity. While other scoring systems exist to evaluate voiding symptomatology, and the DVSS may not be a perfect reflection of symptom severity, we believe this scoring system is clinically relevant as it is the one most commonly used in current practice.
Further limitations lie in the underutilization of our prospective database. Two different nurse practitioners ran the urotherapy sessions; although they obtained statistically similar results when compared to each other, any inconsistencies between the two could lead to a bias of practitioner influence.
Lastly, there was a small subset of patients whose symptoms did not improve even after a few urotherapy sessions. We could have performed a more elaborate analysis on these patients to look into possible explanations that could explain or even predict their lack of success with our training regimen.
Outpatient urotherapy training can be quite effective in treating children with bowel and bladder dysfunction. Constipation plays a role in this condition; further studies may help clarify the effects it may have on response and outcomes following a course of outpatient urotherapy.
With our regimen of an initial 60-minute visit and then 30minute one-on-one training sessions with a nurse practitioner, the greatest improvement in voiding dysfunction was seen after one visit with a small but significant further improvement after the second visit. We have used this information to create a management protocol in which conservative behavioral management is attempted for two outpatient sessions. If patients are still refractory to treatment, then biofeedback and/or possibly pharmacological intervention would be used. Further investigation regarding the exact effect of comorbidities on the speed of symptomatic improvement is required.
Our initial management of pediatric bowel and bladder dysfunction relies on behavioral urotherapy prior to escalation of treatment. The ideal number of visits to achieve maximum effect from this modality alone has not been clearly identified.
To determine the optimal duration of behavioral urotherapy necessary to achieve maximal improvement in the management of pediatric bowel and bladder dysfunction.
A population of 368 patients provided baseline data on the Dysfunctional Voiding Scale Score, Bristol Stool Scale, and uroflowmetry. Comparisons of these measures were then made over six training sessions.
The greatest improvement in bowel and bladder dysfunction was seen after one urotherapy session, although visit 2 was beneficial as well. Worse baseline constipation correlated to worse initial voiding dysfunction. Efficacy of a single session was evident in the report of improvement in a subset of patients who did not return for follow up after their first session
Urotherapy beyond two visits is unlikely to significantly improve symptoms. There is a subset of patients who only require one session to achieve durable results thus negating the need for further follow up.
Level of Evidence--IV
(Polit & Beck, 2012)
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Ramzi Jabaji, Kerrin Palazzi, Ann Marie Berger Finley, Quyen Nguyen, George Kaplan, and George Chiang
Ramzi Jabaji, MD, is a Resident Physician, Kaiser Urology Program, School of Medicine, University of California at San Diego, San Diego, CA.
Kerrin Palazzi, MPH, is a Research Associate, Pediatric Urology, University of California at San Diego, San Diego, CA.
Ann Marie Berger Finley, NP, is a Nurse Practitioner, Pediatric Urology, Rady Children's Hospital at San Diego, San Diego, CA.
Quyen Nguyen, NP, is a Nurse Practitioner, Pediatric Urology, Rady Children's Hospital at San Diego, San Diego, CA.
George Kaplan, MD, is a Professor of Surgery, Pediatric Urology, University of California at San Diego, San Diego, CA.
George Chiang, MD, is a Associate Professor of Surgery, Pediatric Urology, University of California at San Diego.
Table 1. Results for Time of Visit from Baseline, Dysfunctional Voiding Symptom Score (DVSS), DVSS Change, Uroflow Shape, and Bristol Stool Scale (BSS) over Six Testing Times Visit 2 Visit 3 Visit 1 (a) n = 172 n = 78 Measure N = 368 (46.7%) (21.2%) Time to visit from baseline Mdn 56 129 IQR 46 to 80 96 to 161 DVSS Mdn 11 6 4 IQR 8 to 14 3 to 9 2 to 8 DVSS change from baseline Mdn -4 -4.5 IQR -6 to -2 -8 to-1.8 Uroflow shape Bell n 240 120 55 % 82.5 90.2 90.2 Staccato n 41 12 5 % 14.1 9 8.2 Breadloaf/plateau n 10 1 1 % 3.4 0.8 1.6 BSS M 2.7 3.5 3.9 SD 0.7 0.8 0.6 Visit 4 Visit 5 Visit 6 n = 24 n = 9 n = 3 Measure (6.5%) (2.4%) (0.8%) Time to visit from baseline Mdn 174 235 309 IQR 148 to 224 224 to 265 281 to 331 DVSS Mdn 5 5 4 IQR 2.3 to 7 2 to 6 0 to 8 DVSS change from baseline Mdn -4.5 -5 -8 IQR -9 to -2 -10.5 to -2 -11 to 0 Uroflow shape Bell n 12 6 2 % 85.7 100 100 Staccato n 1 0 0 % 7.1 Breadloaf/plateau 0 0 n 1 % 7.1 BSS M 3.8 4.4 3.8 SD 0.8 0.8 0.3 Non- Attendance n = 91 p-Value (24.7%) over Measure Time Time to visit from baseline Mdn 425 IQR 344 to 507 DVSS <0.001 Mdn 3 IQR 0 to 6 DVSS change from baseline Mdn -8 IQR -11 to -4 Uroflow shape 0.513 Bell n % Staccato n % Breadloaf/plateau n % BSS < 0.001 M SD Note: Mdn = median, IQR = interquartile range. (a) Baseline values obtained at time of first visit.
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|Author:||Jabaji, Ramzi; Palazzi, Kerrin; Finley, Ann Marie Berger; Nguyen, Quyen; Kaplan, George; Chiang, Geo|
|Date:||Nov 1, 2014|
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