Long-Term Durability of the Distal Urethral Polypropylene Sling for the Treatment of Stress Urinary Incontinence: Minimum 11-Year Followup

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1 Long-Term Durability of the Distal Urethral Polypropylene Sling for the Treatment of Stress Urinary Incontinence: Minimum 11-Year Followup Lisa Rogo-Gupta,*, Z. Chad Baxter, Ngoc-Bich Le, Shlomo Raz and Larissa V. Rodríguez From the Division of Pelvic Medicine and Reconstructive Surgery, Department of Urology, the Geffen School of Medicine at the University of California Los Angeles, Los Angeles, California Abbreviations and Acronyms CCI Charlson comorbidity index DUPS distal urethral polypropylene sling SUI stress urinary incontinence TVT tension-free vaginal tape UUI urge urinary incontinence Submitted for publication March 8, Study received internal review board approval. * Correspondence: 200 Medical Plaza, Suite #140, Los Angeles, California (telephone: ; FAX: ; lrogogupta@ mednet.ucla.edu). Nothing to disclose. Financial interest and/or other relationship with Astellas and Allergan. Editor s Note: This article is the fifth of 5 published in this issue for which category 1 CME credits can be earned. Instructions for obtaining credits are given with the questions on pages 2022 and Purpose: We report on the long-term outcomes of the distal urethral polypropylene sling for stress urinary incontinence in a patient cohort that was closely followed and whose outcomes were reported at 1 and 5 years after surgery. Materials and Methods: We performed a prospective study of all consecutive patients who underwent a distal urethral polypropylene sling procedure between November 1999 and April The 1 and 5-year outcomes for this particular patient cohort were previously reported. At the minimum 11-year followup, outcome was determined by patient self-assessment including validated questionnaires. Results: A total of 69 patients were followed prospectively and followup was obtained for 30. Of those lost to followup 10 were deceased and 5 were cognitively impaired. Mean patient age at followup was 73 years (range 40 to 97). More than 11 years after surgery 48% of patients reported no stress urinary incontinence symptoms and 63% were never bothered by stress urinary incontinence. Patients reported a mean overall symptom improvement of 64% compared to 81% at 5 years. Overall 82% of patients met the criteria for treatment success by symptom scores and 80% met the criteria by bother scores. Conclusions: The distal urethral polypropylene sling procedure has excellent long-term durability in the treatment of stress urinary incontinence, in addition to low morbidity and low cost as previously described. Eleven years after the procedure the majority of patients report symptom improvement. Nevertheless, many older patients are unable to participate in followup. When choosing an anti-incontinence procedure, durability should be considered in light of patient age given that the theoretical advantages of long-term durability are limited by cognitive decline and mortality. Key Words: urinary incontinence, stress; suburethral slings; urethra; treatment outcome URINARY incontinence is a significant burden to women and to health care systems worldwide. 1 Women spend more than $250 annually on incontinence supplies, with those seeking routine care and treatment spending 3 times as much. 2,3 Incontinence limits the ability to participate in social activities, and has negative psychosocial impacts such as depression, anxiety and frustration. The goal of urinary incontinence treatment is to improve overall quality of life, 4 which is achieved by the majority of women regardless of age or method of surgical treatment. 5, /12/ /0 THE JOURNAL OF UROLOGY Vol. 188, , November by AMERICAN UROLOGICAL ASSOCIATION EDUCATION AND RESEARCH, INC. Printed in U.S.A.

2 DURABILITY OF DISTAL URETHRAL POLYPROPYLENE SLING PROCEDURE 1823 In the last 3 decades the surgical management of SUI has shifted toward a dominance of commercially available polypropylene slings. After the successful introduction of original retropubic and transobturator synthetic polypropylene slings, 7 9 more than 35 additional commercial slings have been introduced into the market. The original techniques as described by Ulmsten 7,8 and Delorme 9 et al are still widely used today, although most slings are commercially produced modifications of the original description. 10 Strips of synthetic and/or biological materials, indicated for placement at the mid urethra, are available for retropubic and transobturator approaches with trocar and nontrocar guidance, with and without fixation mechanisms. 10 We previously described placement under finger guidance of a thinly woven polypropylene sling under the mid to distal urethra (DUPS) without single use instrumentation. 11 The mid to distal urethra was defined as everything distal to the pubourethral ligaments. We previously published 1 and 5-year outcomes, noting a high rate of objective and subjective success. 12,13 In this study we report longer-term subjective outcomes of the same cohort of patients using independent patient driven questionnaires. MATERIALS AND METHODS We performed a prospective study of all consecutive patients who underwent a DUPS procedure between November 1999 and April 2000 at a single institution for the treatment of SUI. All patients who underwent DUPS and whose minimum 5-year followup was reported in 2006 were eligible for the analysis. 13 Preoperative evaluation included history, physical examination, videourodynamics, cystoscopy and symptom questionnaires. The procedure was performed as previously described. 11 Questionnaires were acquired for 11-year followup as previously reported, either obtained in clinic or mailed by a third party who was not the treating urologist. Efforts were made to contact by telephone all missing patients and speak with patients or first-degree relatives. Death records were used as confirmation for patients who could not be located. The original cohort for which 5-year minimum followup was previously presented consisted of 69 patients, of whom 36 (52%) had a history of a prior failed anti-incontinence surgery. 13 Preoperatively 54% reported mixed urinary incontinence and the mean number of prior surgeries was 1.4 (range 0 to 3). Of this cohort 67% had undergone hysterectomy and 73% were postmenopausal. At the time of DUPS 27% underwent concomitant rectocele repair, 9% underwent vaginal hysterectomy and 62% underwent no concomitant repair. This cohort was followed prospectively, and at a minimum of 11 years postoperatively, outcome was determined by patient self-assessment. The questionnaires included validated symptom questionnaires that assessed the presence or absence and frequency of symptoms, the validated short form of the Urogenital Distress Inventory (UDI-6) and the validated Incontinence Symptom Score (ISS-8). 14,15 Scores were reported from 0 to 3 as 0 none, 1 mild, 2 moderate and 3 severe as previously described. 12 Questions related to quality of life due to urinary symptoms, pad use, overall improvement of urinary condition and improvement rating score were also included as previously reported. 12,13 Durability was defined as no significant difference in mean scores at 11 years compared to 1 year. The definition of treatment failure was the same as previously reported, with patients reporting less than 50% improvement, or moderate to severe symptoms, or bother from SUI considered failures. Potential confounders such as urge urinary incontinence, age and comorbidity were assessed. Urge and stress urinary incontinence were assessed using validated patient self-assessment questionnaires as previously detailed. Comorbidity and estimated survival were estimated using the Charlson index. 16 Univariate analysis was performed. The matched pairs t test was used and Pearson correlation coefficients were calculated using Microsoft Excel Patients lost to followup were excluded from the analysis. This study was approved by the University of California Los Angeles internal review board. RESULTS A total of 69 patients who underwent the DUPS procedure for SUI and whose results were reported in 2006 were followed prospectively. Preoperatively all patients had moderate to severe SUI symptoms. 12,13 This patient group at our tertiary referral center was complex. Followup occurred at a minimum of 11 years (mean 11.4, range 11.2 to 11.7). Mean age of our cohort at followup was 73 years (range 40 to 97). Questionnaire data were available for 74% (51), 99% (58) and 42% (30) of the cohort at 1, 5 and 11 years, respectively. Of our cohort 22% (15) was unable to respond because 11 years after the original surgery these patients were identified as deceased or cognitively impaired, and comprised 18% of patients age 50 to 69 years and 41% of those age 75 to 89 years at surgery. Of our cohort 35% (24) was lost to followup. Patient self-assessment questionnaires (from 30 patients) for 11-year followup data are reported as raw score distribution and mean score (table 1). Using ISS question 5 for SUI, 24 patients (82%) met the criteria for treatment success by reporting SUI symptoms as none or mild. These data can be compared to 84% and 93% at 1 and 5 years, respectively. Similarly 24 patients (80%) met the criteria for treatment success by reporting never or mildly being bothered by SUI (UDI-3), compared to 86% and 93% at 1 and 5 years, respectively. The impact of UUI was determined to be clinically relevant in our cohort and was assessed using the same self-assessment questionnaires. When asked to evaluate urge urinary incontinence 67% of patients (20) reported

3 1824 DURABILITY OF DISTAL URETHRAL POLYPROPYLENE SLING PROCEDURE Table 1. Postoperative self-assessed symptoms at 11 years Raw Score No. (%) Mean Score Standard Error Symptom score (ISS) question: Incomplete emptying 1 19 (63) 6 (20) 1 (3) 4 (13) Urgency 2 14 (47) 6 (20) 4 (13) 6 (20) Nocturia 3 2 (7) 17 (57) 10 (33) 1 (3) Daytime frequency 4 11 (37) 11 (37) 8 (27) 0 (0) Stress incontinence 5 14 (48) 10 (34) 1 (3) 4 (14) Urge incontinence 6 9 (30) 11 (37) 1 (3) 9 (30) Leakage-level of activity 7 15 (50) 3 (10) 4 (13) 8 (27) Protection 8 11 (40) 4 (13) 7 (23) 7 (23) Bother score (UDI) question: Frequency 1 8 (27) 6 (20) 10 (33) 6 (20) Urge incontinence 2 10 (33) 11 (37) 2 (7) 7 (23) Stress incontinence 3 19 (63) 5 (17) 0 (0) 6 (20) Small leakage amount 4 10 (33) 10 (33) 3 (10) 7 (23) Difficult emptying 5 19 (63) 8 (27) 1 (3) 2 (7) Pain 6 21 (70) 4 (13) 3 (10) 2 (7) none or mild symptoms (ISS-6) and 70% (21) reported never or mildly being bothered (UDI-2). Durability was measured by comparing mean symptom and bother scores at 1 and 11 years (table 2). At 11 years mean SUI symptom and bother scores were not significantly different from mean scores at 1 year (symptom score p 0.754, bother score p 0.529). Mean symptom and bother scores for UUI also increased from 1 to 11 years, but this increase was not statistically significant (symptom score p 0.576, bother score p 0.428). Symptom progression was defined as an increase in questionnaire score for a given symptom. Of the patients 71% (15) did not demonstrate SUI symptom progression from 1 to 11 years and 82% (18) did not demonstrate daytime frequency progression from 1 to 11 years. On the other hand, 45% of patients (10) demonstrated urge incontinence and nocturia symptom progression in the followup period. The patient determined overall mean improvement in symptoms was 64%, which is a decrease from 80% at 1 year. However, this difference was not statistically significant (p 0.224). Of the patients who considered their condition improved, 48% (14) reported 90% or greater improvement. Failure was reported by 30% of patients (9) at 11 years compared to 5% at 1 and 5 years. The total number of daily pads was included by all patients in addition to the questionnaire re- Table 2. Mean symptom and bother scores were not different at 11 years compared to 1 year No. Responses Mean Score Standard Error (95% CI) p Value (2-sided)* Symptom score (ISS) question 5: SUI 1 yr (control) ( ) SUI 11 yrs ( ) Symptom score (ISS) question 6: UUI 1 yr (control) ( ) UUI 11 yrs ( ) Bother score (UDI) question 2: UUI 1 yr (control) ( ) UUI 11 yrs ( ) Bother score (UDI) question 3: SUI 1 yr (control) ( ) SUI 11 yrs ( ) Compared to before surgery, how much improvement have you experienced? 1 yr (control) ( ) yrs ( ) How many pads do you use for protection in 24 hrs? 1 yr (control) ( ) yrs ( ) * T test for matched pairs.

4 DURABILITY OF DISTAL URETHRAL POLYPROPYLENE SLING PROCEDURE 1825 sponses regardless of indication (incontinence, protection only, hygiene etc). Mean number of pads reported preoperatively by this cohort was 2.84 (range 0 to 18), which significantly improved at 5-year followup to 0.74 (range 0 to 5) as previously reported. Mean pad counts increased at 11-year followup to 2.41 pads per day (range 0 to 15), which was statistically significant compared to 1-year followup (p 0.030), but not significant compared to preoperative pad use (p 0.900). Mean pad count was not correlated with long-term durability (ISS-5 r 0.21, UDI-3 r 0.04) or urge urinary incontinence (ISS-6 r 0.08, UDI-2 r 0.09). A secondary analysis was conducted to evaluate the impact of age and comorbidity on long-term durability in our cohort. Univariate analysis was performed using age at surgery. Age was not correlated with durability (ISS-5 r 0.08, UDI-3 r 0.02) or urge urinary incontinence (ISS-6 r 0.07, UDI-2 r 0.10) in our cohort. The overall rate of urge urinary incontinence (ISS-6 score of 1, 2 or 3) at 5 years was 42%, progressing to 70% at 10 years. The lack of correlation between age and urge urinary incontinence may be due to the multifactorial nature of urge urinary incontinence and the inability to control for other contributing factors with our sample size. Then analysis was performed using measures of comorbidity at surgery. Weighted CCI and estimated 11-year survival rates were calculated for each patient in our cohort. Mean CCI score was 0.58 (range 0 to 4, SD 0.93) at surgery and mean estimated survival was 80% (range 0% to 98%, SD 20%). This analysis revealed the relatively good health status of our cohort. Actual 11-year survival for our cohort was 86%. Weighted CCI was not correlated with durability (ISS-5 r 0.14, UDI-3 r 0.08) or urge urinary incontinence (ISS-6 r 0.01, UDI-2 r 0.02) in our cohort. We evaluated the difference between patients who responded at 11 years and those who were unable to respond. There was no difference in 5-year mean questionnaire scores between patients who did and did not follow up at 11 years for SUI (ISS-5: 0.57 vs 0.26, p 0.71; UDI-3: 0.47 vs 0.26, p 0.77) or UUI (ISS-6: 0.93 vs 0.64, p 0.84; UDI-2: 0.77 vs 0.63, p 0.91). DISCUSSION Synthetic mid urethral slings have largely replaced other SUI treatment methods. Sling procedures are minimally invasive with low morbidity. Multiple reports of successful short-term and midterm outcomes have fueled the rapid adoption of these products. Nevertheless, complications from the blind passage of trocars and cost are limiting factors. Few reports of longer durability are available. 17 In 1999 we introduced the DUPS procedure as a cheaper and safer alternative to commercially available mid urethral retropubic slings. The technique uses finger guidance and avoids complications from blind passage of trocars. We previously presented excellent 1 and 5-year outcomes. In this study we followed the same original cohort of patients and report on a minimum 11-year followup. Our results show that in a group of patients there is excellent durability of the procedure, although we also see that with longer followup and age progression there is increased mortality and new onset of cognitive impairment. Of our cohort 22% (15) was unable to respond because 11 years after the original surgery they had cognitive impairment or were deceased. An additional 35% of our cohort (24) was lost to followup. The durability of DUPS can be compared to outcomes of other incontinence procedures after similar study periods. The Burch colposuspension was previously the most common and successful surgical procedure for patients with urinary incontinence, 18,19 with a long-term success rate of 69% at 11 years. 20 This reported cohort was comprised of complex patients, with 30% having previous operations at the time of Burch (mean 1.5, range 1 to 4). Followup on this cohort was presented for 109 of 336 patients (30%). Few studies have evaluated 11-year outcomes of sling procedures. Randomized trials focus on 1 to 5-year outcomes, leaving long-term evaluation to clinical series and smaller cohorts. The largest multicenter randomized trial comparing Burch to autologous fascial sling demonstrated superior success after sling (66%) vs Burch (49%) at 24 months, with sling also demonstrating greater perioperative morbidity. 21 In a cohort of 90 patients with primary SUI who underwent TVT (Gynecare, Somerville, New Jersey), an evaluation 10 years postoperatively revealed high patient determined subjective (77%) and objective (90%) success rates. 22 It should be noted that this prospective cohort included only those patients with primary stress incontinence, which likely contributed to the high rates of objective and subjective improvement. The Urinary Incontinence Treatment Network recently reported 5-year outcomes of incontinence repair, also noting an increase in incontinence over time. 23 In summary, we demonstrate similar durability for DUPS compared to Burch and TVT in a complex patient cohort. Given the similar clinical outcomes of DUPS compared to Burch and TVT, other factors may influence the decision to use one approach over another. The commercial production of slings in a variety of materials, sizes and surgical approaches has increased their availability to urologists and gynecologists worldwide. However, cost and other resource limitations prohibit some surgeons from adopting single

5 1826 DURABILITY OF DISTAL URETHRAL POLYPROPYLENE SLING PROCEDURE use sling kits, and many have found DUPS to be a cost-effective procedure for routine use. 24 Mean pad count was not correlated with longterm durability of DUPS or UUI. The skewed distribution of pad count and the lack of correlation with 2 common types of urinary incontinence are likely reflections of the variety of indications for pad use. This highlights the importance of using alternative measures to evaluate long-term outcomes and patient satisfaction such as 24-hour pad weight. However, pad weights are not reliable in predicting the etiology of urinary incontinence. 25 Daily pad count is poorly correlated with amount of urine lost and this discrepancy increases with advancing patient age. 26 Women who undergo surgical treatment of SUI are often overweight or obese, current or former smokers, or have chronic illnesses that increase abdominal pressure involving the pulmonary or gastrointestinal systems. Although these risk factors are widely known today, data from small series and epidemiological studies were conflicting at the time of our study design. 27 The relationship between these risk factors and outcomes after sling for recurrent SUI in a patient population with mixed incontinence was not well-known. Therefore, data on these risk factors were not collected prospectively in our cohort and multivariate analysis was not performed. Age was not associated with long-term durability in our cohort, but did provide insight into the likelihood of patients experiencing cognitive decline or death in the 11 years after surgery. In our cohort many patients older than age 70 at sling placement were unable to respond 11 years later due to cognitive limitations or were deceased during followup. This suggests that DUPS would be a sufficient lifetime treatment for these patients. However, patients younger than age 70 years may require additional treatment for urinary incontinence during their lifetime. Age adjusted comorbidity has been demonstrated to predict morbidity and mortality in select patient cohorts. The CCI was initially developed to measure the risk of 1-year mortality due to comorbidity, and has since been adapted and validated for use with administrative data 16,28 but is less successful in predicting outcomes in patients with less morbid illnesses. 29 Our cohort demonstrated low indices and 1-year mortality risk, and analysis revealed that the CCI was unable to predict outcomes as related to incontinence symptoms. Although comorbidities developed in many patients during the study period that ultimately contributed to mortality, few had these conditions at the time of DUPS. One limitation of our study is the complex nature of the patient cohort. The American Urological Association guidelines for the management of SUI target index patients, defined as healthy patients with primary SUI. 30 Our cohort was not comprised of index patients, which may limit the comparison of our outcomes with those of other studies. However, many referral centers have seen a recent increase in women with recurrent and mixed incontinence, and our data reflect good durability of DUPS in these patients. There has also been an evolution in the practice of the DUPS procedure since originally described. The initial DUPS procedure included the option of a suprapubic tube, but with experience this practice was abandoned as the majority of patients voided to completion within 24 hours. In addition, the size of our cohort and the number of patients unable to respond at 11 years are limitations of our study, although we did not demonstrate a significant difference in symptoms at 5 years in patients who responded at 11 years vs those were unable to respond. An intent to treat analysis was performed assuming all patients who did not respond at 11 years were considered treatment failures. In this analysis 20% of the patients (14) reported no SUI symptoms and 28% (19) reported never being bothered by SUI. Overall 49% (34) met the criteria for treatment failure. Larger studies designed to evaluate long-term outcomes compared to alternative treatment options and with sufficient power to perform multivariate analyses are warranted. CONCLUSIONS The DUPS procedure has excellent long-term durability in treating patients with SUI, in addition to the low morbidity and low cost previously described. More than 11 years after the procedure the majority of patients reported symptom improvement, although urinary incontinence worsens over time. Nevertheless, a significant number of patients 70 years old or older treated surgically for SUI are unable to follow up 11 years after surgery due to cognitive limitations or death. When choosing an anti-incontinence procedure, effectiveness and durability need to be considered in light of patient age given that the theoretical advantages of long-term durability are limited by cognitive decline and mortality.

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