Prediction and prevention of stress urinary incontinence after prolapse surgery van der Ploeg, J.M.

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1 UvA-DARE (Digital Academic Repository) Prediction and prevention of stress urinary incontinence after prolapse surgery van der Ploeg, J.M. Link to publication Citation for published version (APA): van der Ploeg, J. M. (2019). Prediction and prevention of stress urinary incontinence after prolapse surgery. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. UvA-DARE is a service provided by the library of the University of Amsterdam ( Download date: 08 Apr 2019

2 Chapter 1 Introduction and outline of thesis

3 Pelvic Organ Prolapse (POP) Pelvic Organ Prolapse (POP) is the descent of one or more pelvic organs into the vagina. (1) Descent of the anterior vaginal wall is caused by a prolapse of the bladder (cystocele). In the middle compartment the uterus or the apex of the vagina (after hysterectomy) might descent. Prolapse of the posterior wall can be caused by rectal protrusion into the lower vagina (rectocele), or higher by a hernia of peritoneum and possibly small bowel (enterocele). Figure 1: Normal anatomy and pelvic organ prolapse uterus bladder prolapsed bladder vagina rectum prolapsed uterus prolapsed rectum Figure 2: Pelvic floor (left) and connective tissue (right) endopelvic fascia coccygeus levator ani iliococcygeus puborectalis obturator internus pubic symphysis urethra rectrum vagina urethra cervix uterosacral ligament cardinal ligament arcus tendineus fasciae pelvis 10

4 Pelvic organ prolapse occurs when the normal supporting structures are damaged. This supporting system consists of pelvic floor muscles and connective tissue (ligaments and fascia). Besides, blood vessels and nerves are necessary for adequate functioning of the supporting system. This supporting system can be damaged by many factors, such as pregnancy, vaginal delivery and chronic straining. Also, weakness in the connective tissue by collagen-associated disorders might predispose damage.(2) The main symptom of pelvic organ prolapse is the feeling of a bulge in or outside the vaginal orifice. Other symptoms can relate to the bladder, bowel and sexual function. With respect to bladder functioning, pelvic organ prolapse is associated with lower urinary tract symptoms such as bladder storage symptoms (e.g. frequency and urgency), voiding symptoms (e.g. slow stream, spraying and incomplete emptying) and urinary incontinence (UI).(2, 3) Stress urinary incontinence (SUI) Stress Urinary Incontinence (SUI) is the involuntary loss of urine during effort, physical exercise, sneezing or coughing.(4) SUI can be regarded as a symptom, sign or condition(4): Symptom: the complaint of losing urine while exercising (also: subjective SUI). Sign: the observation of involuntary leakage from the urethra during effort or physical exertion (also: objective SUI). This is frequently tested with 300 ml bladder filling in lithotomy position during basic office evaluation. Condition: the finding of involuntary leakage from the urethra during filling cystometry (in urodynamics), associated with increased intra-abdominal pressure, in the absence of a detrusor contraction. SUI is caused by an insufficient urethral closure mechanism and arises when bladder pressure exceeds urethral pressure. For adequate urethral closure an effective internal and external urethral sphincter mechanism is necessary. The internal urethral sphincter system consists of a mucosal layer, surrounded by a submucosal sponge, smooth muscle and fibro-elastic tissue and finally a striated muscle layer.(2, 5, 6) The internal urethral muscle is mediated by the autonomic nervous system. SUI can be the result of a diminished coaptation (closure) of the urethral lumen causing low urethral closure pressures. This is called intrinsic sphincter deficiency (ISD) and is typically related to a stovepipe urethra seen during cystoscopy. Common causes for ISD are thought to be: surgical injury, urethral ischemia, or radiation damage.(2) Connective supporting tissue and pelvic floor muscles form the external urethral sphincter system.(6, 7) The external urethral sphincter is attached to the puborectal part of the levator ani muscle. As a result, simultaneous contraction of the levator ani muscle and external urethral sphincter pulls the rectum and vagina anteriorly compressing and kinking the urethra.(7) This external sphincter mechanism is innervated by the somatic (voluntary) nervous system. Damage to the connective tissue support, muscles or nerves, result in hypermobility of the urethra and an insufficient external urethral sphincter system.(2, 5, 6) The pathophysiology of hypermobility have many similarities to that of pelvic organ prolapse. There are still many uncertainties about pathophysiology of SUI, but it is clear that the classical distinction between ISD and hypermobility is inadequate and most women will have elements of both conditions.(2) 11

5 Occult stress urinary incontinence SUI only observed after reduction of coexisting prolapse is called masked or occult SUI. This can be demonstrated in approximately 20% of the women without SUI symptoms.(8, 9) Occult SUI is believed to be associated with kinking or compression of the urethra by the prolapse. (10-12) SUI might also be masked by a windkessel effect caused by a cystocele. The cystocele might work as an elastic reservoir damping the fluctuation in bladder pressure resulting in less exceedance of the urethral pressure. There are still many uncertainties about the causes of occult SUI and several explanations might coexist. Occult SUI is frequently detected by a prolapse reduction stress-test in which the prolapse is redressed by a swab. Visco et al. showed that this method had the best diagnostic value to predict postoperative SUI.(8) Some other methods to demonstrate occult SUI are: a reduction stress-test with a speculum or pessary, manually reduction of the prolapse and a pessary test period to evaluate whether SUI will develop during normal activities. Tests can be done during basic office evaluation or urodynamics and with a subjective full bladder or standardized bladder filling. There is no gold standard on how to detect occult SUI. Women with occult SUI have a higher risk to develop postoperative SUI compared with women without occult SUI, but its predictive value is questionable as other risk factors might play a similar important role (e.g. age, subjective SUI). De novo SUI in women with occult SUI varied in literature between 17-60% (8, 12, 13) and 1-9% (9, 12, 13) underwent subsequent midurethral sling (MUS) for this. Depending on other risk factors of included women, these percentages will differ and thus the predictive value of occult SUI will also vary. Pelvic Organ Prolapse and Stress Urinary Incontinence Because prolapse and SUI can share the same pathophysiology (insufficient support), urethral closure is commonly reduced in women with genital prolapse. This is illustrated by the approximately 50% of the women with prolapse that report co-existing SUI.(14) But also women without co-existing SUI symptoms might have an insufficient urethral closure mechanism. This can become overt after prolapse surgery. About 20% of women without SUI before surgery develop de novo SUI after prolapse surgery.(14) Most likely, SUI was masked in these women by the prolapse; by kinking, or compression of the urethra.(8) Women with prolapse and SUI (observed with or without reduction of the prolapse) have a higher risk to report SUI after prolapse repair.(15) Borstad et al compared prolapse surgery with or without a MUS in women with prolapse and co-existing SUI (as symptom and sign).(16) Three months after prolapse surgery only, almost 60% of the women requested for a MUS because of persisting SUI. This was much lower in a study comparing prolapse surgery with or without MUS in women without symptoms of SUI, but with occult or asymptomatic urodynamic SUI.(9) After 24 months, 9% requested sling surgery after prolapse repair only. 12

6 Combining prolapse and incontinence surgery Bergman et al found in 1995 that after anterior colporrhaphy (cystocele repair) 37% of the women with preoperative SUI became continent.(17) A more recent publication showed that in around 30% of the women SUI was cured after anterior colporrhaphy.(16) It seems likely that restoring anterior wall support reduces hypermobility and improves urethral closure. Although SUI can be cured with prolapse surgery, incontinence procedures are far more effective in treating SUI with cure rates up to 90%.(18) Therefore, to reduce the risk of postoperative SUI one might consider combining prolapse repair with incontinence surgery. While the thought of reducing postoperative SUI with combination surgery is plausible, when we started our project in 2007, there was only limited evidence that combination surgery indeed reduced the risk of postoperative SUI. The CARE trial was in 2006 one of the first randomised trials comparing combination surgery with prolapse surgery only.(19) At three months follow-up, postoperative SUI occurred significantly less frequent after sacrocolpopexy with Burch colposuspension compared to sacrocolpopexy only (24% versus 44%) and less women requested for additional treatment for SUI (5% versus 12%). No randomised study compared prolapse surgery with or without MUS.(20) In 2007, Maher et al concluded in the Cochrane review the following: there were insufficient data to allow evaluation of the impact of prolapse surgery on continence issues, but limited information suggested that concomitant TVT or Burch colposuspension might reduce postoperative incontinence rates.(20) Even less was known about possible risks. Nevertheless, combination surgery was frequently performed. Advocates of combination surgery argued that an incontinence procedure is easy and safe to combine with prolapse surgery and would result in less women needing a second procedure and thus more satisfied women.(21-23) However, in the Netherlands most physicians preferred a two-step policy in which the prolapse is repaired first and incontinence surgery for postoperative SUI is only performed if necessary. We found in an unpublished survey that 50% of the Dutch gynaecologist would perform combination surgery in women with prolapse and co-existing SUI and 35% would do this in women with occult SUI. Opponents of combination surgery argued that a two-step policy was safer. Several arguments were used for the supposedly higher complication risk in combination surgery. First, anatomical changes related to the prolapse might increase preoperative risks such as trocar injury in MUS insertion.(24) Second, changes in the bladder function might increase risk of postoperative voiding dysfunction after combination surgery.(25) Third, obstruction might result in detrusor hypertrophy and de novo overactive bladder symptoms.(26) Finally, a liberal strategy for combining prolapse and incontinence surgery will result in overtreatment and thus unnecessary surgery and more adverse events compared to prolapse surgery only. In fact, there was too little evidence to defend either combination surgery or prolapse surgery only.(27) The degree of overtreatment in combination surgery will of course depend on the preoperative estimated risk to have persisting SUI, or develop de novo SUI after prolapse surgery only. We hypothesized that the risk of postoperative SUI would be highest in women with already a sign or symptom of SUI. In other words: in women with symptomatically or objective SUI (with or without prolapse reduction). If combination surgery would be beneficial, this should especially be appropriate for women with co-existing or occult SUI. 13

7 Aim of the thesis To estimate the value of combination surgery we decided to study this in women with pelvic organ prolapse and co-existing or occult SUI. The following questions were considered essential: 1. Concerning efficacy: Is the risk of postoperative SUI indeed lower after combination surgery than after prolapse surgery only? 2. Concerning adverse events: Is combination surgery safe? 3. Concerning prediction: To prevent overtreatment, can we identify women with a high risk of postoperative SUI that might benefit more from combination surgery than others? On this basis, we defined the following main research questions: 1. Is there a lower risk of postoperative SUI after prolapse surgery combined with a midurethral sling than after prolapse surgery only in women with POP and (a) coexisting SUI or (b) occult SUI? 2. Is the risk of complications higher after combination surgery than after a two-step strategy? 3. Do women with POP and occult SUI have a higher risk of postoperative SUI than women without occult SUI? 4. Are urodynamic studies necessary to predict postoperative SUI or is basic office evaluation sufficient? 5. Can we predict postoperative SUI and what is the value of the stress test in predicting postoperative SUI? To answer these questions, we started the CUPIDO project in The acronym of CUPIDO is: Concomitant surgery and Urodynamic investigation in genital Prolapse and stress Incontinence, a Diagnostic study including Outcome evaluation (CUPIDO). We performed a meta-analysis of randomised trials published from to study the risks and benefits of combination surgery.(15) In 2010 we published the protocol for the CUPIDO trials (Chapter 2), in which postoperative SUI was compared in vaginal prolapse surgery with and without a midurethral sling (MUS).(28) The CUPIDO-1 trial aimed at women with coexisting SUI (Chapter 3), while the CUPIDO-2 trial aimed at continent women (Chapter 4).(29, 30) Combining the data of both trials, we studied the predictive value of occult SUI during basic office evaluation and urodynamic studies in symptomatically continent women (Chapter 5).(31) Because more trials were published we updated our meta-analysis with studies published between (Chapter 6).(32) In a clinical opinion paper we discussed two concepts on how risks and benefits of combination surgery might be balanced when prolapse surgery with a MUS is considered (Chapter 7). Finally, we developed and internally validated a prediction model for postoperative SUI and studied the additional value of the stress test (Chapter 8). 14