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Factors Influencing the Outcome of Mid Urethral Sling Procedures for Female Urinary Incontinence
Factors Influencing the Outcome of Mid Urethral Sling Procedures for Female Urinary Incontinence Jae-Seung Paick, Min Chul Cho, Seung-June Oh, Soo Woong Kim and Ja Hyeon Ku* From the Department of Urology, Seoul National University Hospital, Seoul, Korea
Purpose: We evaluated the outcome at least 6 months after the tension-free vaginal tape or transobturator tape procedure in women with urinary incontinence, and identified factors predicting persistent stress urinary incontinence. Materials and Methods: A total of 464 women 28 to 80 years old (mean age 56) were included in the study. Tension-free vaginal tape (252) and transobturator tape (212) procedures were performed by the same surgeon. Mean followup was 10.8 months (range 6 to 52). Results: Bladder perforations were noted in 12 patients (4.8%) in the tension-free vaginal tape group but there was no bladder perforation after the transobturator tape procedure (p ⫽ 0.001). The rate of urinary retention in the tension-free vaginal tape group was significantly higher than that in the transobturator tape group (15.1% vs 6.6%, p ⫽ 0.004). The overall cure rate was significantly higher in the tension-free vaginal tape group than in the transobturator tape group (92.1% vs 84.9%, p ⫽ 0.015). On multivariate analysis 4 variables were independent risk factors for persistent stress urinary incontinence, that is comorbid disease (OR 2.37, 95% CI 1.26 – 4.47, p ⫽ 0.008), urge urinary incontinence (OR 1.95, 95% CI 1.02–3.74, p ⫽ 0.044), severe grade of cystocele (OR 2.73, 95% CI 1.43–5.20, p ⫽ 0.002) and transobturator tape procedure (OR 2.87, 95% CI 1.50 –5.47, p ⫽ 0.001). Conclusions: The cure rates in women with urinary incontinence are not similar after tension-free vaginal tape and transobturator tape procedures. Our findings suggest that characteristics including the type of procedure, comorbid diseases, mixed urinary incontinence and severe grade cystocele should be considered high risk factors for persistent stress urinary incontinence in these patients. Key Words: urinary incontinence, urethra, polypropylenes, suburethral slings
ative incontinence undermines the success rate perceived by the patient and physician. We evaluated the outcome at least 6 months after TVT or TOT in women with UI, and identified factors predicting persistent postoperative stress UI in these patients.
rinary incontinence, defined by the ICS as “a complaint of any involuntary leakage of urine,” is a common problem.1 In 1996 a new surgical technique called the tension-free vaginal tape procedure was proposed for UI.2 Based on the integral theory, the aim of this technique is to reinforce pubourethral ligaments and the suburethral vaginal hammock as well as the connections of the latter to the pubococcygeus muscles.3 Subsequently the attractiveness to patients of such minimally invasive techniques has resulted in several modified versions of the TVT procedure, including the transobturator tape procedure.4 These procedures aim to restore urethral support by synthetic sling placement at the level of the mid urethra. These techniques can be performed with the patient under local anesthesia, decreasing hospital stay and postoperative recovery. Recent reports indicate a long-term success rate of more than 80% on objective and subjective assessment.5,6 However, there are few data on factors predicting the outcome of these operations and the effect of patient characteristics on outcome has not been systemically addressed. Identifying factors that can be associated with persistent UI after surgery is of the utmost importance because postoper-
U
PATIENTS AND METHODS Between January 2000 and March 2006 the clinical records of 506 women with complaints of UI who underwent mid urethral sling procedures (TVT or TOT) were retrospectively reviewed. In Korea the TVT procedure was introduced first and then TOT was done. The first TVT procedure at our institution was performed in March 1999. Starting in May 2004 we performed the TOT procedure in patients with UI. Our protocol included history and physical examination, urinalysis, urine culture, uroflowmetry, PVR urine measurement, 1-hour pad test and multichannel videourodynamic studies. Approval for this study was provided by the Internal Review Board of the Seoul National University Hospital. The study inclusion criteria were female, having UI and age greater than 18 years. The study exclusion criteria were presence of any urinary tract infection, malignancy, pregnancy and postoperative followup of less than 6 months. In cases with an incomplete evaluation or incomplete information, the results were also excluded from the final analysis. A total of 464 women 28 to 80 years old (mean age 56) were included in the study. The sample size calculation was per-
Submitted for publication January 16, 2007. Study received Internal Review Board approval. * Correspondence: Department of Urology, Seoul National University Hospital, 28, Yongon Dong, Jongno Ku, Seoul 110-744, Korea (telephone: 82-2-2072-0361; FAX: 82-2-742-4665; e-mail: randyku@ hanmail.net).
0022-5347/07/1783-0985/0 THE JOURNAL OF UROLOGY® Copyright © 2007 by AMERICAN UROLOGICAL ASSOCIATION
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Vol. 178, 985-989, September 2007 Printed in U.S.A. DOI:10.1016/j.juro.2007.05.026
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OUTCOME AFTER MID URETHRAL SLING
formed assuming a 90% cure rate with TVT, and that a 10% difference in cure rate between procedures would be clinically important.7 To detect this level of difference with 80% power would require 197 patients in each arm of the trial. Stress UI was defined as involuntary leakage on effort, exertion, sneezing or coughing and urge UI was defined as the complaint of involuntary leakage accompanied by or immediately preceded by urgency.1 The severity of UI was classified using the Ingelman-Sundberg scale.8 Information regarding comorbid diseases (eg asthma, diabetes, hypertension) was obtained from patient history and/or patient charts. The degree of the cystocele was assessed according to the work of Juma et al.9 Urethral hypermobility was assessed with the Q-tip test. The 1-hour pad test was performed as recommended by the ICS.1 Uroflowmetry was performed with the patient in the sitting position. Videourodynamics were performed using a 6Fr dual lumen vesical catheter and a 9Fr rectal balloon catheter at medium filling. VLPP was assessed with the patient standing at a bladder volume of 200 ml and defined as minimal intra-abdominal pressure in the absence of involuntary detrusor contraction at which fluid was visualized emanating from the urethral meatus during the Valsalva maneuver. A standard urethral pressure profilometry study was performed at an infusion rate of 4 ml per minute and a catheter withdrawal rate of 1 mm per second. Maximum urethral closure pressure was the difference between maximal urethral pressure and bladder pressure and was recorded. All definitions corresponded to those of the ICS.1 Of the patients 114 (24.6%) reported additional urge UI episodes. Pharmacotherapy was not given to decrease or eliminate urge UI preoperatively. Patients with mixed UI were counseled that the procedure was not designed as a primary treatment to ameliorate or cure urge UI and these postoperative symptoms were likely to remain the same or worsen. Procedures were performed mostly with the patient under local anesthesia. The TVT and TOT procedures were performed by the same surgeon (JSP) as reported by Ulmsten and Delorme et al, respectively.2,4 Cystoscopy was done to verify absent bladder injury. Cystocele repair was not performed in all patients. The catheter was removed 3 hours after surgery unless bladder perforation had been observed during surgery. When PVR volume was more than 100 ml or the patient did not void, she was instructed in clean intermittent self-catheterization and asked to catheterize at least 4 times daily until PVR urine was less than 100 ml. Patients were followed at 1, 6 and 12 months, and every year thereafter. Mean followup was 10.8 months (range 6 to 52) and no difference in followup duration was found according to procedure type. Followup evaluation included nonvalidated questionnaire assessment, physical examination with stress test, 1-hour pad test, uroflowmetry and PVR measurement. All patients underwent cough stress testing in the supine and standing positions at 300 ml bladder filling. Cure of UI after the procedure was defined as the absence of a subjective complaint of leakage and the absence of objective leakage on stress testing. Improvement was defined as no urine loss on stress test plus patient report of some leakage but overall satisfaction, and was considered failure. In the present study all cases except cure were considered failure. Statistical analysis was performed using the Student t test for continuous data, and Fisher’s exact test, chi-square
test or Armitage test for categorical data. To determine the influencing factors for persistent UI after procedures we used logistic regression analysis. Variables that were p value less than 0.05 on univariate analysis were included in the multivariate logistic model. A 5% level of significance was used for all statistical testing and all statistical tests were 2-sided. The statistical analyses were performed using the commercially available program SPSS® 11.0. RESULTS Table 1 shows the baseline characteristics of the groups. Mean parity was 3.0 for the TVT group and 2.4 for the TOT group (p ⬍0.001). The rate of hysterectomy in the TVT group was significantly lower than that in the TOT group (p ⫽ 0.03). The TVT group had a more severe grade of cystocele than the TOT group (p ⫽ 0.004). The severity of UI was greater in the TVT group than the TOT group (p ⬍0.001). The amounts of urine leakage during the 1-hour pad test were 34.1 gm for the TVT group and 45.9 gm for the TOT group (p ⫽ 0.009). Qmax in the TVT group was significantly higher than that in the TOT group (p ⬍0.001). No difference in other characteristics was observed in the 2 groups. Bladder perforations were noted in 12 patients (4.8%) in the TVT group but no bladder perforations occurred after
TABLE 1. Patient characteristics TVT No. pts Mean pt age ⫾ SE Mean cm ht ⫾ SE Mean kg wt ⫾ SE Mean kg/m2 body mass index ⫾ SE Mean No. parity ⫾ SE No. hysterectomy (%) No. comorbid diseases (%) No. incontinence surgery (%) No. urgency (%) No. urge incontinence (%) Mean mos symptoms ⫾ SE No. cystocele (%): None Grade I Grade II Grade III No. symptom severity (%): Grade I Grade II Grade III Mean degrees on Q-tip test ⫾ SE Mean gm on 1-hr pad test ⫾ SE Mean ml/sec Qmax ⫾ SE Mean ml PVR ⫾ SE Mean cm H2O VLPP ⫾ SE Mean cm H2O MUCP ⫾ SE Mean ml max cystometric capacity ⫾ SE No. uninhibited detrusor contraction (%) No. anesthesia (%): Local Regional General Mean mos followup ⫾ SE * Student’s t test. † Chi-square test. ‡ Armitage test.
252 54.9 155.8 59.8 24.6
⫾ ⫾ ⫾ ⫾
TOT 212 55.4 156.0 60.8 25.0
⫾ ⫾ ⫾ ⫾
0.6 0.4 0.6 0.2
0.516* 0.815* 0.181* 0.213*
3.0 ⫾ 0.1 50 (19.8) 120 (47.6) 10 (4.0) 88 (34.9) 66 (26.2) 104.4 ⫾ 6.0
2.4 ⫾ 0.1 60 (28.3) 102 (48.1) 14 (6.6) 88 (41.5) 48 (22.6) 86.1 ⫾ 5.6
⬍0.001* 0.033† 0.915† 0.202† 0.145† 0.376† 0.025* 0.004‡
12 (4.8) 150 (59.5) 82 (32.5) 8 (3.2)
34 (16.0) 122 (57.5) 45 (21.2) 11 (5.2)
6 (2.4) 90 (35.7) 156 (61.9) 31.6 ⫾ 0.8
21 (9.9) 125 (59.0) 66 (31.1) 32.3 ⫾ 1.1
0.616*
34.1 ⫾ 3.3
45.9 ⫾ 3.1
0.009*
31.6 20.1 78.6 60.4 378.3
⫾ ⫾ ⫾ ⫾ ⫾
0.6 0.3 0.5 0.2
p Value
0.7 2.4 2.1 1.4 4.8
22.8 22.4 74.9 61.0 394.6
⫾ ⫾ ⫾ ⫾ ⫾
0.7 2.2 2.2 1.6 6.5
12 (4.8)
13 (5.2)
242 (96.0) 8 (3.2) 2 (0.8) 10.6 ⫾ 0.5
204 (96.2) 5 (2.4) 3 (1.4) 11.0 ⫾ 0.4
⬍0.001‡
⬍0.001* 0.484* 0.222* 0.763* 0.044* 0.515† 0.861‡
0.538*
OUTCOME AFTER MID URETHRAL SLING TABLE 2. Postoperative results
No. pts No. bladder injury (%) Mean gm on 1-hr pad test ⫾ SE Mean ml/sec Qmax ⫾ SE Mean ml PVR ⫾ SE No. urinary retention (%) No. cure rate (%)
TVT
TOT
p Value
252 12 (4.8) 3.9 ⫾ 2.0
212 0 (0.0) 2.9 ⫾ 0.9
0.001* 0.706†
21.7 ⫾ 0.7 47.3 ⫾ 5.6 38 (15.1) 232 (92.1)
25.7 ⫾ 0.8 29.9 ⫾ 5.5 14 (6.6) 180 (84.9)
⬍0.001† 0.028† 0.004‡ 0.015‡
* Fisher’s exact test. † Student’s t test. ‡ Chi-square test.
987
2.35, 95% CI 1.30 – 4.25, p ⫽ 0.005), TOT procedure (OR 2.06, 95% CI 1.14 –3.73, p ⫽ 0.017) and longer followup (OR 1.04, 95% CI 1.01–1.07, p ⫽ 0.026). To exclude the possibility of confounder effect, these 5 variables were selected for the multivariate logistic model to determine the independent predictors of persistent stress UI. In the multivariate model, whereas duration of followup lost statistical significance, all other variables were independent risk factors for persistent stress UI. The results are shown in table 3. DISCUSSION
the TOT procedure (p ⫽ 0.001). Postoperatively Qmax for the TVT and TOT groups was 21.7 and 25.7 ml per second, respectively (p ⬍0.001). PVR was higher in the TVT group than in the TOT group (p ⫽ 0.028). The rate of urinary retention (defined as PVR greater than 100 ml or did not void) in the TVT group was also significantly higher than in the TOT group (p ⫽ 0.004). However, the amount of urine leakage during the 1-hour pad test after surgery was not significantly different between the 2 groups. Furthermore, the overall cure rate was significantly higher in the TVT group than in the TOT group (92.1% vs 84.9%, p ⫽ 0.015) (table 2). To evaluate the factors influencing persistent stress UI after the procedures, a logistic regression analysis was performed. On univariate analysis the odds ratios (95% CI, between high and low quartile) for persistent stress UI were increased for 5 factors, that is comorbid disease (OR 2.45, 95% CI 1.33– 4.52, p ⫽ 0.004), urge incontinence (OR 1.92, 95% CI 1.05–3.53, p ⫽ 0.036), severe grade of cystocele (OR
In the present study the TOT procedure seems to be safer than the TVT procedure because TOT is associated with a lower rate of bladder injury and urinary retention is more frequent in the TVT group. However, there was a significant difference in cure rate between the 2 groups. Previous prospective, randomized trials suggested that TOT would be the procedure of choice because TOT is equally effective with fewer complications. In a randomized trial by deTayrac et al clinical results were similar for the TVT and TOT groups.10 Liapis et al noted that the objective cure rate for TVT and TOT groups was 89% and 90%, respectively.11 In a randomized comparative trial in Finland no significant differences in objective and subjective cure rates were detected. However, the TOT group had more complications than the TVT group, although the difference was not regarded as clinically significant.12 However, these studies did not account for patient characteristics as a potential predictor of surgery failure. The sling axis in the TVT is roughly perpendicular to the urethral axis while the axis of TOT is less acute to the urethral
TABLE 3. Univariate and multivariate predictors of postoperative stress incontinence
Age Ht (cm) Wt (kg) Body mass index (kg/m2) Parity (No.) Hysterectomy Comorbid diseases Incontinence surgery Urgency Urge incontinence Mos symptoms Cystocele: None–grade I Grade II–III Symptom severity: Grade I Grade II Grade III Q-tip test 1-Hr pad test (gm) Qmax (ml/sec) PVR (ml) VLPP (cm H2O) MUCP (cm H2O) Max cystometric capacity (ml) Uninhibited detrusor contraction Anesthesia: Local General or regional Procedure: TVT TOT Mos followup
OR (95% CI)
p Value
1.024 (0.992–1.057) 0.968 (0.916–1.023) 1.013 (0.976–1.050) 1.070 (0.971–1.179) 1.178 (0.876–1.584) 1.348 (0.709–2.563) 2.455 (1.332–4.523) 2.237 (0.797–6.274) 1.299 (0.684–2.206) 1.921 (1.045–3.533) 1.000 (0.997–1.003)
0.151 0.251 0.504 0.171 0.279 0.362 0.004 0.126 0.491 0.036 0.928
1.000 2.349 (1.299–4.247)
0.005
1.000 1.343 (0.381–4.730) 0.964 (0.269–3.450) 1.005 (0.983–1.026) 1.000 (0.992–1.008) 0.983 (0.958–1.010) 1.002 (0.993–1.011) 0.991 (0.981–1.001) 0.999 (0.986–1.012) 1.000 (0.996–1.003) 2.085 (0.748–5.815)
0.647 0.955 0.670 0.926 0.219 0.700 0.078 0.869 0.904 0.160
1.000 0.987 (0.218–4.377)
0.976
1.000 2.062 (1.141–3.726) 1.038 (1.005–1.073)
0.017 0.026
Adjusted OR (95% CI)
p Value
2.367 (1.255–4.465)
0.008
1.953 (1.019–3.740)
0.044
1.000 2.731 (1.434–5.202)
0.002
1.000 2.867 (1.501–5.473) 1.036 (1.000–1.073)
0.001 0.051
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OUTCOME AFTER MID URETHRAL SLING
axis. Therefore, one would expect a higher failure rate with TOT in women with intrinsic sphincter deficiency due to less circumferential compression of the urethra. Miller et al found that the TOT was nearly 6 times more likely to fail than TVT at 3 months after surgery in women with MUCP 42 cm H2O or less.13 A recent study revealed that the odds of continued stress UI following TOT were 12 times greater for women with VLPP 60 cm H2O or less compared to those with VLPP more than 60 cm H2O.14 However, in fact there is no difference in the distance between the middle of the tape and the bladder neck among cured cases, failure, bladder outlet obstruction and de novo urgency after TOT and TVT.15 Therefore, because the continence mechanism in women is not completely understood, additional research is needed to resolve this controversy and to clarify the underlying mechanisms involved. To date, the effect of patient characteristics on the outcome of mid urethral sling procedures has not been systemically addressed. We tried to determine the independent risk factors of persistent stress UI after the procedure. In the multivariate model severe grade of cystocele was one of independent risk factors for persistent stress UI. To our knowledge this finding has not been previously described. It is well-known that women who require surgical correction of stress UI have a high incidence of concomitant pelvic support defects that require surgical repair.16,17 Interestingly, a randomized comparison between the Burch colposuspension and anterior colporrhaphy procedures revealed that neither procedure alone was successful in treating the patient with stress UI and clinically significant cystocele.18 Because concurrent pelvic organ prolapse repairs have been performed safely during surgery for stress UI, these additional procedures may contribute to the overall success of the surgical management of UI and should not be overlooked. Recognition of the severity and types of pelvic organ prolapse in a given patient may be imperative in devising an appropriate operative approach. In addition, we found the presence of combined urge UI to be another risk factor for persistent stress UI. Recently Kulseng-Hanssen et al reported that 72% of women with mixed UI were cured after undergoing TVT.19 They found that women with mixed incontinence with predominant urge UI had a worse cure rate than those with predominant stress UI (80% vs 52%). It is also possible that patients with mixed UI symptoms do not really have 2 separate pathological conditions. Rather, mixed symptoms may be due to a more severe form of stress predominant UI.20 This may be an explanation of why mixed symptoms may resolve after successful anti-incontinence procedures. Some limitations should be pointed out with regard to the study design. The population size was small and the followup period was relatively short. In addition, this study was not a prevalence study because we recruited study subjects from the clinic, making it difficult to generalize the study results. Our study also included only Korean women. Therefore, our results may not be applicable to other races and cultures. Finally, although all the data were collected prospectively as part of an ongoing departmental audit, our study was not a randomized trial. Therefore, additional research including randomized trials is needed to confirm these findings.
CONCLUSIONS The cure rates in women with UI are not similar after TVT and TOT procedures. Our findings suggest that characteristics including type of procedure, comorbid diseases, mixed UI and severe grade cystocele should be considered high risk factors of persistent stress UI in these patients. This has important clinical relevance because patients should be informed of this possibility.
ICS MUCP PVR Qmax TOT TVT UI VLPP
⫽ ⫽ ⫽ ⫽ ⫽ ⫽ ⫽ ⫽
Abbreviations and Acronyms International Continence Society maximum urethral closure pressure post-void residual maximum flow rate transobturator tape tension-free vaginal tape urinary incontinence Valsalva leak point pressure
REFERENCES 1.
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Abrams P, Cardozo L, Fall M, Griffiths D, Rosier P, Ulmsten U et al: The standardisation of terminology of lower urinary tract function: report from the standardisation sub-committee of the International Continence Society. Neurourol Urodyn 2002; 21: 167. Ulmsten U, Henriksson L, Johnson P and Varhos G: An ambulatory surgical procedure under local anesthesia for treatment of female urinary incontinence. Int Urogynecol J Pelvic Floor Dysfunct 1996; 7: 81. Petros PE and Ulmsten UI: An integral theory and its method for the diagnosis and management of female urinary incontinence. Scand J Urol Nephrol, suppl., 1993; 153: 1. Delorme E, Droupy S, de Tayrac R and Delmas V: Transobturator tape (Uratape): a new minimally-invasive procedure to treat female urinary incontinence. Eur Urol 2004; 45: 203. Ankardal M, Heiwall B, Lausten-Thomsen N, Carnelid J and Milsom I: Short- and long-term results of the tension-free vaginal tape procedure in the treatment of female urinary incontinence. Acta Obstet Gynecol Scand 2006; 85: 986. Doo CK, Hong B, Chung BJ, Kim JY, Jung HC, Lee KS et al: Five-year outcomes of the tension-free vaginal tape procedure for treatment of female stress urinary incontinence. Eur Urol 2006; 50: 333. Ward K, Hilton P and United Kingdom and Ireland Tensionfree Vaginal Tape Trial Group: Prospective multicentre randomised trial of tension-free vaginal tape and colposuspension as primary treatment for stress incontinence. BMJ 2002; 325: 67. Ingelman-Sundberg A and Ulmsten U: Surgical treatment of female urinary stress incontinence. Contrib Gynecol Obstet 1983; 10: 51. Juma S, Little NA and Raz S: Evaluation of stress urinary incontinence. In: Gynecologic and Obstetric Urology. Edited by HJ Buchsbaum and JD Schmidt. Philadelphia: WB Saunders 1993; pp 251–263. deTayrac R, Deffieux X, Droupy S, Chauveaud-Lambling A, Calvanese-Benamour L and Fernandez H: A prospective randomized trial comparing tension-free vaginal tape and transobturator suburethral tape for surgical treatment of stress urinary incontinence. Am J Obstet Gynecol 2004; 190: 602. Liapis A, Bakas P, Giner M and Creatsas G: Tension-free vaginal tape versus tension-free vaginal tape obturator in
OUTCOME AFTER MID URETHRAL SLING
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women with stress urinary incontinence. Gynecol Obstet Invest 2006; 62: 160. Laurikainen E, Valpas A, Kivela A, Kalliola T, Rinne K, Takala T et al: Retropubic compared with transobturator tape placement in treatment of urinary incontinence: a randomized controlled trial. Obstet Gynecol 2007; 109: 4. Miller JJ, Botros SM, Akl MN, Aschkenazi SO, Beaumont JL, Goldberg RP et al: Is transobturator tape as effective as tension-free vaginal tape in patients with borderline maximum urethral closure pressure? Am J Obstet Gynecol 2006; 195: 1799. O’Connor RC, Nanigian DK, Lyon MB, Ellison LM, Bales GT and Stone AR: Early outcomes of mid-urethral slings for female stress urinary incontinence stratified by valsalva leak point pressure. Neurourol Urodyn 2006; 25: 685. de Tayrac R, Deffieux X, Resten A, Doumerc S, Jouffroy C and Fernandez H: A transvaginal ultrasound study comparing transobturator tape and tension-free vaginal tape after surgical treatment of female stress urinary incontinence. Int Urogynecol J Pelvic Floor Dusfunct 2006; 17: 466. Ng CS, Rackley RR and Appell RA: Incidence of concomitant procedures for pelvic organ prolapse and reconstruction in women who undergo surgery for stress urinary incontinence. Urology 2001; 57: 911. Hart SR, Moore RD, Miklos JR, Mattox TF and Kohli N: Incidence of concomitant surgery for pelvic organ prolapse in patients surgically treated for stress urinary incontinence. J Reprod Med 2006; 51: 521. Colombo M, Vitobello D, Proietti F and Milani R: Randomised comparison of Burch colposuspension versus anterior colporrhaphy in women with stress urinary incontinence and anterior vaginal wall prolapse. BJOG 2000; 107: 544. Kulseng-Hanssen S, Husby H and Schiotz HA: The tension free vaginal tape operation for women with mixed incontinence: do preoperative variables predict the outcome? Neurourol Urodyn 2007; 26: 115. Bump RC, Norton PA, Zinner NR, Yalcin I and Duloxetine Urinary Incontinence Study Group: Mixed urinary incontinence symptoms: urodynamic findings, incontinence severity, and treatment response. Obstet Gynecol 2003; 102: 76.
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EDITORIAL COMMENT This study by Paick et al is a large retrospective review of 464 women who underwent either TVT or TOT performed by a single surgeon at a single institution. A multivariate analysis revealed that comorbid disease, urge incontinence, a severe grade cystocele and the TOT procedure were risk factors for persistent stress urinary incontinence. Although this was not a randomized trial and the groups receiving the different slings were dissimilar, the multivariate analysis does allow comparisons. This is one of the first studies to suggest that the TOT may have inferior surgical efficacy compared to the TVT. Similar to other studies, the subjects with the TOT procedure had less retention than TVT subjects. It may be that the more acute U-shaped angle of the TVT is more effective in preventing stress urinary incontinence, but also more likely to obstruct. This study further supports the need for high quality, appropriately powered, randomized trials of retropubic compared to transobturator mid urethral slings. Charles W. Nager University of California, San Diego Medical Center San Diego, California REPLY BY AUTHORS With recent advances in minimally invasive techniques for urinary incontinence, identifying factors that can be associated with outcomes after surgery may be important to help patients make appropriate decisions. Our study would suggest that the TOT procedure is safer than the TVT procedure due to a lower rate of bladder injury and urinary retention but may be less effective for curing urinary incontinence. We believe that this has important clinical relevance because patients should be informed of this possibility. We agree that high quality randomized trials are needed to verify these findings.
Purpose: We evaluated the outcome at least 6 months after the tension-free vaginal tape or transobturator tape procedure in women with urinary incontinence, and identified factors predicting persistent stress urinary incontinence. Materials and Methods: A total of 464 women 28 to 80 years old (mean age 56) were included in the study. Tension-free vaginal tape (252) and transobturator tape (212) procedures were performed by the same surgeon. Mean followup was 10.8 months (range 6 to 52). Results: Bladder perforations were noted in 12 patients (4.8%) in the tension-free vaginal tape group but there was no bladder perforation after the transobturator tape procedure (p ⫽ 0.001). The rate of urinary retention in the tension-free vaginal tape group was significantly higher than that in the transobturator tape group (15.1% vs 6.6%, p ⫽ 0.004). The overall cure rate was significantly higher in the tension-free vaginal tape group than in the transobturator tape group (92.1% vs 84.9%, p ⫽ 0.015). On multivariate analysis 4 variables were independent risk factors for persistent stress urinary incontinence, that is comorbid disease (OR 2.37, 95% CI 1.26 – 4.47, p ⫽ 0.008), urge urinary incontinence (OR 1.95, 95% CI 1.02–3.74, p ⫽ 0.044), severe grade of cystocele (OR 2.73, 95% CI 1.43–5.20, p ⫽ 0.002) and transobturator tape procedure (OR 2.87, 95% CI 1.50 –5.47, p ⫽ 0.001). Conclusions: The cure rates in women with urinary incontinence are not similar after tension-free vaginal tape and transobturator tape procedures. Our findings suggest that characteristics including the type of procedure, comorbid diseases, mixed urinary incontinence and severe grade cystocele should be considered high risk factors for persistent stress urinary incontinence in these patients. Key Words: urinary incontinence, urethra, polypropylenes, suburethral slings
ative incontinence undermines the success rate perceived by the patient and physician. We evaluated the outcome at least 6 months after TVT or TOT in women with UI, and identified factors predicting persistent postoperative stress UI in these patients.
rinary incontinence, defined by the ICS as “a complaint of any involuntary leakage of urine,” is a common problem.1 In 1996 a new surgical technique called the tension-free vaginal tape procedure was proposed for UI.2 Based on the integral theory, the aim of this technique is to reinforce pubourethral ligaments and the suburethral vaginal hammock as well as the connections of the latter to the pubococcygeus muscles.3 Subsequently the attractiveness to patients of such minimally invasive techniques has resulted in several modified versions of the TVT procedure, including the transobturator tape procedure.4 These procedures aim to restore urethral support by synthetic sling placement at the level of the mid urethra. These techniques can be performed with the patient under local anesthesia, decreasing hospital stay and postoperative recovery. Recent reports indicate a long-term success rate of more than 80% on objective and subjective assessment.5,6 However, there are few data on factors predicting the outcome of these operations and the effect of patient characteristics on outcome has not been systemically addressed. Identifying factors that can be associated with persistent UI after surgery is of the utmost importance because postoper-
U
PATIENTS AND METHODS Between January 2000 and March 2006 the clinical records of 506 women with complaints of UI who underwent mid urethral sling procedures (TVT or TOT) were retrospectively reviewed. In Korea the TVT procedure was introduced first and then TOT was done. The first TVT procedure at our institution was performed in March 1999. Starting in May 2004 we performed the TOT procedure in patients with UI. Our protocol included history and physical examination, urinalysis, urine culture, uroflowmetry, PVR urine measurement, 1-hour pad test and multichannel videourodynamic studies. Approval for this study was provided by the Internal Review Board of the Seoul National University Hospital. The study inclusion criteria were female, having UI and age greater than 18 years. The study exclusion criteria were presence of any urinary tract infection, malignancy, pregnancy and postoperative followup of less than 6 months. In cases with an incomplete evaluation or incomplete information, the results were also excluded from the final analysis. A total of 464 women 28 to 80 years old (mean age 56) were included in the study. The sample size calculation was per-
Submitted for publication January 16, 2007. Study received Internal Review Board approval. * Correspondence: Department of Urology, Seoul National University Hospital, 28, Yongon Dong, Jongno Ku, Seoul 110-744, Korea (telephone: 82-2-2072-0361; FAX: 82-2-742-4665; e-mail: randyku@ hanmail.net).
0022-5347/07/1783-0985/0 THE JOURNAL OF UROLOGY® Copyright © 2007 by AMERICAN UROLOGICAL ASSOCIATION
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Vol. 178, 985-989, September 2007 Printed in U.S.A. DOI:10.1016/j.juro.2007.05.026
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OUTCOME AFTER MID URETHRAL SLING
formed assuming a 90% cure rate with TVT, and that a 10% difference in cure rate between procedures would be clinically important.7 To detect this level of difference with 80% power would require 197 patients in each arm of the trial. Stress UI was defined as involuntary leakage on effort, exertion, sneezing or coughing and urge UI was defined as the complaint of involuntary leakage accompanied by or immediately preceded by urgency.1 The severity of UI was classified using the Ingelman-Sundberg scale.8 Information regarding comorbid diseases (eg asthma, diabetes, hypertension) was obtained from patient history and/or patient charts. The degree of the cystocele was assessed according to the work of Juma et al.9 Urethral hypermobility was assessed with the Q-tip test. The 1-hour pad test was performed as recommended by the ICS.1 Uroflowmetry was performed with the patient in the sitting position. Videourodynamics were performed using a 6Fr dual lumen vesical catheter and a 9Fr rectal balloon catheter at medium filling. VLPP was assessed with the patient standing at a bladder volume of 200 ml and defined as minimal intra-abdominal pressure in the absence of involuntary detrusor contraction at which fluid was visualized emanating from the urethral meatus during the Valsalva maneuver. A standard urethral pressure profilometry study was performed at an infusion rate of 4 ml per minute and a catheter withdrawal rate of 1 mm per second. Maximum urethral closure pressure was the difference between maximal urethral pressure and bladder pressure and was recorded. All definitions corresponded to those of the ICS.1 Of the patients 114 (24.6%) reported additional urge UI episodes. Pharmacotherapy was not given to decrease or eliminate urge UI preoperatively. Patients with mixed UI were counseled that the procedure was not designed as a primary treatment to ameliorate or cure urge UI and these postoperative symptoms were likely to remain the same or worsen. Procedures were performed mostly with the patient under local anesthesia. The TVT and TOT procedures were performed by the same surgeon (JSP) as reported by Ulmsten and Delorme et al, respectively.2,4 Cystoscopy was done to verify absent bladder injury. Cystocele repair was not performed in all patients. The catheter was removed 3 hours after surgery unless bladder perforation had been observed during surgery. When PVR volume was more than 100 ml or the patient did not void, she was instructed in clean intermittent self-catheterization and asked to catheterize at least 4 times daily until PVR urine was less than 100 ml. Patients were followed at 1, 6 and 12 months, and every year thereafter. Mean followup was 10.8 months (range 6 to 52) and no difference in followup duration was found according to procedure type. Followup evaluation included nonvalidated questionnaire assessment, physical examination with stress test, 1-hour pad test, uroflowmetry and PVR measurement. All patients underwent cough stress testing in the supine and standing positions at 300 ml bladder filling. Cure of UI after the procedure was defined as the absence of a subjective complaint of leakage and the absence of objective leakage on stress testing. Improvement was defined as no urine loss on stress test plus patient report of some leakage but overall satisfaction, and was considered failure. In the present study all cases except cure were considered failure. Statistical analysis was performed using the Student t test for continuous data, and Fisher’s exact test, chi-square
test or Armitage test for categorical data. To determine the influencing factors for persistent UI after procedures we used logistic regression analysis. Variables that were p value less than 0.05 on univariate analysis were included in the multivariate logistic model. A 5% level of significance was used for all statistical testing and all statistical tests were 2-sided. The statistical analyses were performed using the commercially available program SPSS® 11.0. RESULTS Table 1 shows the baseline characteristics of the groups. Mean parity was 3.0 for the TVT group and 2.4 for the TOT group (p ⬍0.001). The rate of hysterectomy in the TVT group was significantly lower than that in the TOT group (p ⫽ 0.03). The TVT group had a more severe grade of cystocele than the TOT group (p ⫽ 0.004). The severity of UI was greater in the TVT group than the TOT group (p ⬍0.001). The amounts of urine leakage during the 1-hour pad test were 34.1 gm for the TVT group and 45.9 gm for the TOT group (p ⫽ 0.009). Qmax in the TVT group was significantly higher than that in the TOT group (p ⬍0.001). No difference in other characteristics was observed in the 2 groups. Bladder perforations were noted in 12 patients (4.8%) in the TVT group but no bladder perforations occurred after
TABLE 1. Patient characteristics TVT No. pts Mean pt age ⫾ SE Mean cm ht ⫾ SE Mean kg wt ⫾ SE Mean kg/m2 body mass index ⫾ SE Mean No. parity ⫾ SE No. hysterectomy (%) No. comorbid diseases (%) No. incontinence surgery (%) No. urgency (%) No. urge incontinence (%) Mean mos symptoms ⫾ SE No. cystocele (%): None Grade I Grade II Grade III No. symptom severity (%): Grade I Grade II Grade III Mean degrees on Q-tip test ⫾ SE Mean gm on 1-hr pad test ⫾ SE Mean ml/sec Qmax ⫾ SE Mean ml PVR ⫾ SE Mean cm H2O VLPP ⫾ SE Mean cm H2O MUCP ⫾ SE Mean ml max cystometric capacity ⫾ SE No. uninhibited detrusor contraction (%) No. anesthesia (%): Local Regional General Mean mos followup ⫾ SE * Student’s t test. † Chi-square test. ‡ Armitage test.
252 54.9 155.8 59.8 24.6
⫾ ⫾ ⫾ ⫾
TOT 212 55.4 156.0 60.8 25.0
⫾ ⫾ ⫾ ⫾
0.6 0.4 0.6 0.2
0.516* 0.815* 0.181* 0.213*
3.0 ⫾ 0.1 50 (19.8) 120 (47.6) 10 (4.0) 88 (34.9) 66 (26.2) 104.4 ⫾ 6.0
2.4 ⫾ 0.1 60 (28.3) 102 (48.1) 14 (6.6) 88 (41.5) 48 (22.6) 86.1 ⫾ 5.6
⬍0.001* 0.033† 0.915† 0.202† 0.145† 0.376† 0.025* 0.004‡
12 (4.8) 150 (59.5) 82 (32.5) 8 (3.2)
34 (16.0) 122 (57.5) 45 (21.2) 11 (5.2)
6 (2.4) 90 (35.7) 156 (61.9) 31.6 ⫾ 0.8
21 (9.9) 125 (59.0) 66 (31.1) 32.3 ⫾ 1.1
0.616*
34.1 ⫾ 3.3
45.9 ⫾ 3.1
0.009*
31.6 20.1 78.6 60.4 378.3
⫾ ⫾ ⫾ ⫾ ⫾
0.6 0.3 0.5 0.2
p Value
0.7 2.4 2.1 1.4 4.8
22.8 22.4 74.9 61.0 394.6
⫾ ⫾ ⫾ ⫾ ⫾
0.7 2.2 2.2 1.6 6.5
12 (4.8)
13 (5.2)
242 (96.0) 8 (3.2) 2 (0.8) 10.6 ⫾ 0.5
204 (96.2) 5 (2.4) 3 (1.4) 11.0 ⫾ 0.4
⬍0.001‡
⬍0.001* 0.484* 0.222* 0.763* 0.044* 0.515† 0.861‡
0.538*
OUTCOME AFTER MID URETHRAL SLING TABLE 2. Postoperative results
No. pts No. bladder injury (%) Mean gm on 1-hr pad test ⫾ SE Mean ml/sec Qmax ⫾ SE Mean ml PVR ⫾ SE No. urinary retention (%) No. cure rate (%)
TVT
TOT
p Value
252 12 (4.8) 3.9 ⫾ 2.0
212 0 (0.0) 2.9 ⫾ 0.9
0.001* 0.706†
21.7 ⫾ 0.7 47.3 ⫾ 5.6 38 (15.1) 232 (92.1)
25.7 ⫾ 0.8 29.9 ⫾ 5.5 14 (6.6) 180 (84.9)
⬍0.001† 0.028† 0.004‡ 0.015‡
* Fisher’s exact test. † Student’s t test. ‡ Chi-square test.
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2.35, 95% CI 1.30 – 4.25, p ⫽ 0.005), TOT procedure (OR 2.06, 95% CI 1.14 –3.73, p ⫽ 0.017) and longer followup (OR 1.04, 95% CI 1.01–1.07, p ⫽ 0.026). To exclude the possibility of confounder effect, these 5 variables were selected for the multivariate logistic model to determine the independent predictors of persistent stress UI. In the multivariate model, whereas duration of followup lost statistical significance, all other variables were independent risk factors for persistent stress UI. The results are shown in table 3. DISCUSSION
the TOT procedure (p ⫽ 0.001). Postoperatively Qmax for the TVT and TOT groups was 21.7 and 25.7 ml per second, respectively (p ⬍0.001). PVR was higher in the TVT group than in the TOT group (p ⫽ 0.028). The rate of urinary retention (defined as PVR greater than 100 ml or did not void) in the TVT group was also significantly higher than in the TOT group (p ⫽ 0.004). However, the amount of urine leakage during the 1-hour pad test after surgery was not significantly different between the 2 groups. Furthermore, the overall cure rate was significantly higher in the TVT group than in the TOT group (92.1% vs 84.9%, p ⫽ 0.015) (table 2). To evaluate the factors influencing persistent stress UI after the procedures, a logistic regression analysis was performed. On univariate analysis the odds ratios (95% CI, between high and low quartile) for persistent stress UI were increased for 5 factors, that is comorbid disease (OR 2.45, 95% CI 1.33– 4.52, p ⫽ 0.004), urge incontinence (OR 1.92, 95% CI 1.05–3.53, p ⫽ 0.036), severe grade of cystocele (OR
In the present study the TOT procedure seems to be safer than the TVT procedure because TOT is associated with a lower rate of bladder injury and urinary retention is more frequent in the TVT group. However, there was a significant difference in cure rate between the 2 groups. Previous prospective, randomized trials suggested that TOT would be the procedure of choice because TOT is equally effective with fewer complications. In a randomized trial by deTayrac et al clinical results were similar for the TVT and TOT groups.10 Liapis et al noted that the objective cure rate for TVT and TOT groups was 89% and 90%, respectively.11 In a randomized comparative trial in Finland no significant differences in objective and subjective cure rates were detected. However, the TOT group had more complications than the TVT group, although the difference was not regarded as clinically significant.12 However, these studies did not account for patient characteristics as a potential predictor of surgery failure. The sling axis in the TVT is roughly perpendicular to the urethral axis while the axis of TOT is less acute to the urethral
TABLE 3. Univariate and multivariate predictors of postoperative stress incontinence
Age Ht (cm) Wt (kg) Body mass index (kg/m2) Parity (No.) Hysterectomy Comorbid diseases Incontinence surgery Urgency Urge incontinence Mos symptoms Cystocele: None–grade I Grade II–III Symptom severity: Grade I Grade II Grade III Q-tip test 1-Hr pad test (gm) Qmax (ml/sec) PVR (ml) VLPP (cm H2O) MUCP (cm H2O) Max cystometric capacity (ml) Uninhibited detrusor contraction Anesthesia: Local General or regional Procedure: TVT TOT Mos followup
OR (95% CI)
p Value
1.024 (0.992–1.057) 0.968 (0.916–1.023) 1.013 (0.976–1.050) 1.070 (0.971–1.179) 1.178 (0.876–1.584) 1.348 (0.709–2.563) 2.455 (1.332–4.523) 2.237 (0.797–6.274) 1.299 (0.684–2.206) 1.921 (1.045–3.533) 1.000 (0.997–1.003)
0.151 0.251 0.504 0.171 0.279 0.362 0.004 0.126 0.491 0.036 0.928
1.000 2.349 (1.299–4.247)
0.005
1.000 1.343 (0.381–4.730) 0.964 (0.269–3.450) 1.005 (0.983–1.026) 1.000 (0.992–1.008) 0.983 (0.958–1.010) 1.002 (0.993–1.011) 0.991 (0.981–1.001) 0.999 (0.986–1.012) 1.000 (0.996–1.003) 2.085 (0.748–5.815)
0.647 0.955 0.670 0.926 0.219 0.700 0.078 0.869 0.904 0.160
1.000 0.987 (0.218–4.377)
0.976
1.000 2.062 (1.141–3.726) 1.038 (1.005–1.073)
0.017 0.026
Adjusted OR (95% CI)
p Value
2.367 (1.255–4.465)
0.008
1.953 (1.019–3.740)
0.044
1.000 2.731 (1.434–5.202)
0.002
1.000 2.867 (1.501–5.473) 1.036 (1.000–1.073)
0.001 0.051
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OUTCOME AFTER MID URETHRAL SLING
axis. Therefore, one would expect a higher failure rate with TOT in women with intrinsic sphincter deficiency due to less circumferential compression of the urethra. Miller et al found that the TOT was nearly 6 times more likely to fail than TVT at 3 months after surgery in women with MUCP 42 cm H2O or less.13 A recent study revealed that the odds of continued stress UI following TOT were 12 times greater for women with VLPP 60 cm H2O or less compared to those with VLPP more than 60 cm H2O.14 However, in fact there is no difference in the distance between the middle of the tape and the bladder neck among cured cases, failure, bladder outlet obstruction and de novo urgency after TOT and TVT.15 Therefore, because the continence mechanism in women is not completely understood, additional research is needed to resolve this controversy and to clarify the underlying mechanisms involved. To date, the effect of patient characteristics on the outcome of mid urethral sling procedures has not been systemically addressed. We tried to determine the independent risk factors of persistent stress UI after the procedure. In the multivariate model severe grade of cystocele was one of independent risk factors for persistent stress UI. To our knowledge this finding has not been previously described. It is well-known that women who require surgical correction of stress UI have a high incidence of concomitant pelvic support defects that require surgical repair.16,17 Interestingly, a randomized comparison between the Burch colposuspension and anterior colporrhaphy procedures revealed that neither procedure alone was successful in treating the patient with stress UI and clinically significant cystocele.18 Because concurrent pelvic organ prolapse repairs have been performed safely during surgery for stress UI, these additional procedures may contribute to the overall success of the surgical management of UI and should not be overlooked. Recognition of the severity and types of pelvic organ prolapse in a given patient may be imperative in devising an appropriate operative approach. In addition, we found the presence of combined urge UI to be another risk factor for persistent stress UI. Recently Kulseng-Hanssen et al reported that 72% of women with mixed UI were cured after undergoing TVT.19 They found that women with mixed incontinence with predominant urge UI had a worse cure rate than those with predominant stress UI (80% vs 52%). It is also possible that patients with mixed UI symptoms do not really have 2 separate pathological conditions. Rather, mixed symptoms may be due to a more severe form of stress predominant UI.20 This may be an explanation of why mixed symptoms may resolve after successful anti-incontinence procedures. Some limitations should be pointed out with regard to the study design. The population size was small and the followup period was relatively short. In addition, this study was not a prevalence study because we recruited study subjects from the clinic, making it difficult to generalize the study results. Our study also included only Korean women. Therefore, our results may not be applicable to other races and cultures. Finally, although all the data were collected prospectively as part of an ongoing departmental audit, our study was not a randomized trial. Therefore, additional research including randomized trials is needed to confirm these findings.
CONCLUSIONS The cure rates in women with UI are not similar after TVT and TOT procedures. Our findings suggest that characteristics including type of procedure, comorbid diseases, mixed UI and severe grade cystocele should be considered high risk factors of persistent stress UI in these patients. This has important clinical relevance because patients should be informed of this possibility.
ICS MUCP PVR Qmax TOT TVT UI VLPP
⫽ ⫽ ⫽ ⫽ ⫽ ⫽ ⫽ ⫽
Abbreviations and Acronyms International Continence Society maximum urethral closure pressure post-void residual maximum flow rate transobturator tape tension-free vaginal tape urinary incontinence Valsalva leak point pressure
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women with stress urinary incontinence. Gynecol Obstet Invest 2006; 62: 160. Laurikainen E, Valpas A, Kivela A, Kalliola T, Rinne K, Takala T et al: Retropubic compared with transobturator tape placement in treatment of urinary incontinence: a randomized controlled trial. Obstet Gynecol 2007; 109: 4. Miller JJ, Botros SM, Akl MN, Aschkenazi SO, Beaumont JL, Goldberg RP et al: Is transobturator tape as effective as tension-free vaginal tape in patients with borderline maximum urethral closure pressure? Am J Obstet Gynecol 2006; 195: 1799. O’Connor RC, Nanigian DK, Lyon MB, Ellison LM, Bales GT and Stone AR: Early outcomes of mid-urethral slings for female stress urinary incontinence stratified by valsalva leak point pressure. Neurourol Urodyn 2006; 25: 685. de Tayrac R, Deffieux X, Resten A, Doumerc S, Jouffroy C and Fernandez H: A transvaginal ultrasound study comparing transobturator tape and tension-free vaginal tape after surgical treatment of female stress urinary incontinence. Int Urogynecol J Pelvic Floor Dusfunct 2006; 17: 466. Ng CS, Rackley RR and Appell RA: Incidence of concomitant procedures for pelvic organ prolapse and reconstruction in women who undergo surgery for stress urinary incontinence. Urology 2001; 57: 911. Hart SR, Moore RD, Miklos JR, Mattox TF and Kohli N: Incidence of concomitant surgery for pelvic organ prolapse in patients surgically treated for stress urinary incontinence. J Reprod Med 2006; 51: 521. Colombo M, Vitobello D, Proietti F and Milani R: Randomised comparison of Burch colposuspension versus anterior colporrhaphy in women with stress urinary incontinence and anterior vaginal wall prolapse. BJOG 2000; 107: 544. Kulseng-Hanssen S, Husby H and Schiotz HA: The tension free vaginal tape operation for women with mixed incontinence: do preoperative variables predict the outcome? Neurourol Urodyn 2007; 26: 115. Bump RC, Norton PA, Zinner NR, Yalcin I and Duloxetine Urinary Incontinence Study Group: Mixed urinary incontinence symptoms: urodynamic findings, incontinence severity, and treatment response. Obstet Gynecol 2003; 102: 76.
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EDITORIAL COMMENT This study by Paick et al is a large retrospective review of 464 women who underwent either TVT or TOT performed by a single surgeon at a single institution. A multivariate analysis revealed that comorbid disease, urge incontinence, a severe grade cystocele and the TOT procedure were risk factors for persistent stress urinary incontinence. Although this was not a randomized trial and the groups receiving the different slings were dissimilar, the multivariate analysis does allow comparisons. This is one of the first studies to suggest that the TOT may have inferior surgical efficacy compared to the TVT. Similar to other studies, the subjects with the TOT procedure had less retention than TVT subjects. It may be that the more acute U-shaped angle of the TVT is more effective in preventing stress urinary incontinence, but also more likely to obstruct. This study further supports the need for high quality, appropriately powered, randomized trials of retropubic compared to transobturator mid urethral slings. Charles W. Nager University of California, San Diego Medical Center San Diego, California REPLY BY AUTHORS With recent advances in minimally invasive techniques for urinary incontinence, identifying factors that can be associated with outcomes after surgery may be important to help patients make appropriate decisions. Our study would suggest that the TOT procedure is safer than the TVT procedure due to a lower rate of bladder injury and urinary retention but may be less effective for curing urinary incontinence. We believe that this has important clinical relevance because patients should be informed of this possibility. We agree that high quality randomized trials are needed to verify these findings.