Highlights of the 27th Annual Scientific Meeting of the American Urogynecologic Society (AUGS)

October 19-21, 2006; Palm Springs, California

Victoria L. Handa, MD, FACOG

Disclosures

January 24, 2007

In This Article

Introduction

The 27th annual Scientific Meeting of the American Urogynecologic Society (AUGS) was held October 19-21, 2006 in Palm Springs, California. The meeting included 55 oral presentations, 91 posters, and 50 exhibitors. This report will describe some of the most important information and data presented during the meeting, with a focus on clinically relevant topics.

Lessons From the Past: Directions for the Future

Changes in reconstructive surgery over the past 40 years were the focus of the keynote address delivered by Dr. Donald Ostergard,[1] past president of the society and a founding member of AUGS. He highlighted the trend toward increased industry involvement in surgical innovation and raised concerns about the current US Food and Drug Administration (FDA) regulatory process for approving new surgical implants. A summary by Boyles and colleagues[2] is recommended to readers wanting more specific information about the current approval process. Of greatest significance, requirements for approval of a new implant are quite different from those for a new medication. Specifically, proof of safety and efficacy may not be required, and approval can be awarded on the basis of a product under review being "substantially equivalent" to a device already on the market.

To illustrate an inherent problem in the regulatory process, Dr. Ostergard traced a sequence that began with the Vesica procedure and led to approval of the currently popular transobturator tape. The Vesica procedure was introduced in the early 1990s for the surgical treatment of stress incontinence. It combined the concept of the needle-suspension (eg, similar to the Peyreyra procedure) with use of bone anchors for stabilization of the bladder neck. Despite the initial commercial success of the "surgical kit" required for performing the Vesica procedure, it was subsequently found to be less effective than other options (such as Burch urethropexy), and largely abandoned. However, the procedure is considered a watershed -- the first requiring use of a specific surgical kit marketed for profit and thus initiating the trend toward more industry-sponsored surgical innovation -- a trend that has not always resulted in successful products.

Next, the FDA approved the ProteGen sling (1996), based on the contention that it was substantially similar to the Vesica. The ProteGen sling employed the Vesica concept of suspension via bone anchors, but added a sling made from a synthetic mesh product coated with bovine collagen.

The ProteGen sling was withdrawn from the market in 1999 because it was found to be associated with higher than expected rate of vaginal erosion and dehiscence and did not appear to function as intended.[1] When announcing the recall, the FDA described the ProteGen sling as "adulterated and misbranded," apparently on the basis of the postmarketing data. At least 1 class action lawsuit resulted from complications associated with the ProteGen sling.

Of interest, the first published results of an investigation related to the ProteGen sling did not appear in the medical literature until after market withdrawal.[3] Additionally, a recent search on the term "ProteGen" on Pubmed did not locate even a single publication addressing product efficacy. Therefore, surgeons using the sling from 1997 to 1999 did so without support from any published scientific evidence. Dr. Ostergard contended that the lack of safety and efficacy data, as well as the FDA comments about the product at time of recall, put surgeons at a distinct disadvantage for defending product-related malpractice suits.

FDA approval of currently popular transobturator tape was based on the claim that this product is substantially equivalent to transvaginal tape slings. The first transvaginal sling (approved in 1998) was based on its substantial equivalence to the ProteGen sling, which in turn had been approved due to similarity to the Vesica. This means that transobturator tape ultimately received FDA approval based on similarity to a product labeled as defective and withdrawn from the market. Additionally, approval of the defective ProGen sling was based on the Vesica procedure, a product that was quickly found to be substantially less effective than existing surgical procedures.

Dr. Ostergard used this illustration to encourage the AUGS membership to support increasing FDA oversight of the approval process for new devices. He maintained that manufacturers of new devices should be required to present substantial safety and efficacy data prior to approval. Such premarketing data could be used by surgeons and consumers to make educated decisions about options.

In the current climate, there is no incentive for manufacturers of new devices to provide such data to the public. At present, surgeons considering the use of a new device have to rely on expert opinion, anecdotal experience of colleagues, or marketing information from the manufacturer. Without adequate information, the possibility that associated problems will not be identified until a new device has been used on hundreds or possibly thousands of women is significantly increased. Other examples of products successfully marketed but later withdrawn for safety concerns were cited to emphasize that the medical-legal implications of using unproven products or devices should always be carefully considered. Surgeries involving such devices could be deemed "experimental" by third-party payers or malpractice carriers, with physicians held liable for associated complications and malpractice coverage denied.

Leadership in surgical innovation was encouraged by Dr. Ostergard. He cited the changes in naming convention - in the past, surgical procedures were named for the surgeon who developed the technique (eg, "Burch"), but during the current era, reconstructive surgeries are named after commercial products (eg, tension-free vaginal tape [TVT]).

In keeping with this theme, a session on "New Apical Support Surgeries" offered by Drs. Kris Strohbehn and Douglass Hale[4] highlighted a discussion of the role for commercially available kits for treatment of apical prolapse, including Perigee (AMS), Avaulta (Bard Urological), and Prolift (Gynecare).

Audience member Dr. Matt Barber noted: "We are chasing a moving target," remarking that new products are introduced faster than can be evaluated in clinical trials, and unsuccessful products may then be taken off the market, modified, renamed, and reintroduced. Since these products are being widely used and successfully marketed with scant published data, there is very little commercial incentive to publish results. Dr. Hale estimated that over 2000 women receive apical support implants each month, despite a paucity of published safety and efficacy data.

Three ideas to improve available information about new products were offered by Dr. Hale:

  1. Creation of a national database for tracking results and complications of new surgical implants. He contended that clinicians should share the responsibility for evaluating the performance of commercial products. Industry cannot be the scapegoat for irresponsible implementation of unproven technology. Mandatory reporting of complications, with failure to report resulting in a penalty (such as loss of privilege to present or publish data), was also suggested.

  2. Cooperation between AUGS and other professional organizations. AUGS has successfully partnered with the pharmaceutical industry, and can also work together with other organizations to identify options with the best outcomes for patients.

  3. Petitioning for revision of the 510K process. This process is currently too lenient when it comes to new surgical products and does not afford enough protection for patients or clinicians.

In a related poster presentation, Dr. S. Pulliam and colleagues[5] presented the results of a survey related to the use of synthetic mesh in pelvic reconstructive surgery. These authors surveyed the AUGS membership (31% response rate) and found that 59% of respondents use permanent mesh in anterior and posterior vaginal repair on at least some occasions. Those who use mesh were more likely male (74%) and more likely to be in private practice (80%). Those who had not undergone formal fellowship training were 2.5 times more likely to use mesh in these procedures. Nevertheless, 33% of respondents were "very concerned" about mesh erosions or exposures after vaginal repair procedures. These results suggest that formally trained urogynecologists and those in academic practice may be less likely to use mesh for these procedures, based perhaps on weak scientific evidence to support this practice.

The safety and efficacy of specific surgical implants utilizing long-term data were also described. Dr. Robert D. Moore[6] presented 1-year data on the Monarc transobturator tape (TOT) sling product. This worldwide study (funded by the manufacturer) followed 272 women for 1 year after surgery. Women with confirmed stress incontinence and urethral hypermobility were treated by 26 investigators (including investigators at 11 US sites).

Mean operative time was 13 minutes (intraoperative cystoscopy was not routine at all centers); 90% of women were discharged without a catheter. Data showed a 2.3% incidence of postoperative groin pain, which resolved without intervention. One woman required a sling release for retention. Subjective success rate was 87%; 92% had a negative cough stress test at 1 year.

These are useful results that can be considered in counseling women considering an anti-incontinence procedure. It was noted that there was no comparison arm, but this is the type of safety and efficacy data that should be expected before adopting new surgical techniques. Ideally, a comparative trial would allow clinicians to understand the relative benefits of this approach compared with more established alternatives, such as midurethral slings.

Dr. Nathan Guerette[7] presented 1-year data from a randomized trial of anterior repair with and without a bovine pericardium graft for the treatment of anterior vaginal wall prolapse. Ninety-four women were enrolled at 3 centers over a 3-year period. Women with stage II-IV prolapse of the anterior wall were included. The investigators found no differences in intraoperative complications, operative time, or postoperative complications (although power to detect differences was limited by the small sample). At 1 year, there were no differences in support between groups.

Findings from this study did not support the use of a bovine pericardial graft to augment anterior vaginal repair. The investigators commented on a possible trend toward deterioration in support in the nonaugmented group, but this difference was not significant at 1 year. It is hoped that long-term studies will address the question of whether a difference can be detected over several years of follow-up.

Finally, Dr. Pamela Moalli[8] presented data regarding the tensile properties of commercially available urinary incontinence sling meshes. Using the Gynecare TVT as the gold standard, the investigators compared slings manufactured by Mentor (Aris), AMS (Monarc/Sparc), Boston Scientific (Advantage/Obtryx), Caldera (T-sling), and Bard (Uretex). Findings showed the Gynecare TVT mesh was easily deformed (elongated) at very low loads, but became stiffer at higher loads. The TVT sling could be elongated to 110% of its original length prior to failure (rupture). The properties of the AMS sling were similar to the Gynecare sling. The arms of the Boston Scientific sling were similar to the Gynecare and AMS materials, but the heat-sealed midsection of the Boston Scientific sling was significantly stiffer. The stiffest grafts were the Mentor and Caldera slings, demonstrating a single high uniform stiffness with increasing loads.

This study was not intended to investigate the optimal mechanical properties, but rather to compare the properties of available materials. The researchers suggested that maximum stiffness and maximum load at failure -- properties currently presented in commercial literature -- are not clinically meaningful. They hope to define the most clinically meaningful parameters with respect to in vivo performance of these materials.

Pelvic Organ Prolapse

A second theme at this year's meeting was the definition of normal and abnormal pelvic organ support. Research has shown that more than 50% of women have at least some evidence of prolapse on physical examination. This observation raises the question of how to define prolapse and how to distinguish normal from abnormal support. A related question is the weak correlation between the severity and symptoms of anatomic prolapse.

Several presentations addressed these questions. In a cross-sectional study, Dr. Jerry Lowder and colleagues[9] described the relationship between prolapse symptoms and severity in a population of 337 women seeking consultation for pelvic floor disorders. The majority of women in this population had stage III prolapse (eg, the leading edge of the prolapse was at least 1 cm beyond the hymen with valsalva), with 75% of the women aware of a vaginal protrusion.

Their data suggest a gradual increase in symptoms and bother with increasing anatomic severity of prolapse. Specifically, among women with prolapse at the hymen or 1 cm above the hymen, approximately one quarter were bothered by a protrusion. This proportion increased to 50% when prolapse was 1 cm beyond the hymen, and 85% when prolapse was more than 1-2 cm beyond the hymen. Thus, a physical protrusion may not be symptomatic until it extends at least 2 cm beyond the hymen. By contrast, it was interesting to note that even for women with prolapse 7 cm beyond the hymen, less than 100% could feel the bulge and more than 10% reported no bother related to that degree of severe prolapse.

A limitation of this investigation, raised by an audience member, was that asymptomatic women were less likely to be represented, as the population was limited to women seeking care for pelvic floor disorders. A longitudinal study would be better suited to describe the transition from asymptomatic to symptomatic prolapse for individual women.

The prize for best clinical research was awarded to Dr. Cate Bradley[10] and colleagues for the investigation, "The Natural History of Pelvic Organ Prolapse in Older Women: a 4-year Longitudinal Study." This research was an ancillary study of the Women's Health Initiative (WHI). WHI participants at the University of Iowa site, where the Bradley study was conducted, were examined annually, using the POP-Q examination to characterize vaginal and uterine support. "Prolapse" was defined as descent of the vaginal walls or cervix beyond the hymen. Results were based on 2-4 annual examinations for 259 women.

Data showed that the severity of prolapse varied from year to year in individual women; 6% demonstrated at least 2 cm worsening of prolapse per year, while 1% demonstrated an annual improvement of similar magnitude. A surprising finding was the incidence of prolapse in this population: 26% per year. In other words, 25% of women developed new-onset prolapse each year.

An equally surprising finding was the resolution of prolapse in 21% of women per year. The factors associated with an increased risk of progression (ie, prolapse worsening) were less severe prolapse at baseline, increased body mass index (BMI), and a history of more vaginal births. The researchers concluded that some cases of "progression" and "regression" were due to natural variability in the measurement of vaginal support and were less likely to represent clinically meaningful worsening or improvement.

It should be noted that this study was limited to women who had not had a hysterectomy prior to menopause and, therefore, women who developed prolapse earlier in life were most likely excluded from the study. Another important finding was that women randomized to the estrogen treatment arm of the WHI were neither at greater nor lower risk of progression, suggesting that estrogen treatment doesn't affect pelvic organ support over 2-4 years of therapy.

Finally, in a population-based study, Drs. Whitcomb and Lukacz[11] presented findings from a study of the impact of prolapse and other pelvic floor disorders on sexual function. They specifically assessed whether sexual activity and satisfaction were different between women with and without pelvic floor disorders. These data build on recently published results from their "KP Cares" study.[12]

In their most recent investigation, 12,200 members of Kaiser Permanente were surveyed, and 4458 (37%) returned their questionnaires. Stress urinary incontinence, overactive bladder, fecal incontinence, and pelvic organ prolapse were identified by questionnaire; no physical examination for prolapse was done.

The relationships between sexual function and these 4 pelvic floor disorders were based on results of questionnaire responses. Among the two thirds (n = 2620) with a sexual partner, 86% were sexually active. In a multivariable analysis controlling for age, marital status, libido, and several other factors, no differences in sexual activity or sexual satisfaction for women with or without prolapse (or any pelvic floor disorder) were demonstrated.

The conference audience was somewhat amused to hear that divorce was one of the variables most strongly associated with both increased sexual activity and sexual satisfaction. Specifically, the odds of sexual activity were 3 times higher for divorced women, and divorce was the only factor associated with improved sexual satisfaction. Age, menopause status, and libido were also significantly associated with sexual activity and sexual function. Overall, the results suggested that pelvic floor disorders are not the most important determinants of female sexual function (when controlling for confounding factors). However, clinicians should keep in mind that this population was a community sample and therefore these results may not be relevant to women seeking treatment for pelvic floor disorders.

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