Surgical Treatment for Stress Urinary Incontinence in Women: Novelties,Concerns and Ethics

Abstract

The International Continence Society (ICS) is the largest international body of nurses, physical therapists, Drug researchers, clinicians, gynecologists, urologists and other specialists united yearly to discuss the topic of incontinence. This year, over 2500 attendees from all over the world participated in the annual meeting held in Glasgow, Scotland. Several presentations deserve recognition, but we will focus on a few key issues, such as the latest information on the surgical treatment of stress urinary incontinence, a novel approach to patient's study participation in randomized controlled trials via internet recruitment, and ethical concerns related to disclosure and transparency, as these are keenly relevant topics in women's health.

41st Annual Meeting of the International Continence Society

Glasgow, Scotland, UK, 29 August-2 September 2011

Over the last 20 years, traditional surgical treatments for stress urinary incontinence (SUI) have seen an evolution, from the use of autologous tissues (Burch procedure, autologous fascial slings) to the insertion of synthetic devices around the urethra, also called suburethral tapes. These tapes aim to reinforce the midurethra where the defective continence mechanism presumably resides and are, thus, called midurethral slings. This new technology gained rapid popularity because the procedure is relatively short and little training is necessary to learn the steps of this method. Despite complications – some serious – the main procedure, named tension-free vaginal tape (TVT), described by Ulmsten and colleagues in 1996 [1], became widely adopted until another variant, the trans-obturator tape (TOT), proposed by Delorme in 2002 [2] challenged it. The TOT obviated the risks of bladder injury (related to the passage of the TVT trocars behind the pubic bone, just in front of the anterior part of the bladder) and voiding dysfunction (tape too tight causing a reduction in urethral caliber), but introduced new problems related to vaginal erosion and groin pain. The efficiency was also debated, as many suspected a less obstructive mechanism from the TOT compared with TVT, and hence, a possibly lower level of patient satisfaction in resolving SUI. Recently, a third generation of so-called ‘mini-slings’ (MS) has appeared, with the intent of performing this corrective procedure under local anesthesia and possibly in the office setting or an ambulatory care center. It is unfortunate, however, that this technical evolution has been carried out with a lofty goal in mind (to help women suffering from SUI), but in the absence of a structured investigative approach. Therefore, the existing data on these procedures are limited and the long-term safety and efficacy remain unknown. This statement holds true for the TOT [3], MS, and to a lesser extent for the TVT, although only one long-term study at 11 years has been published by the originators of the procedure in a subset of followed patients with a 77% cure rate [4]. Therefore, long-term caution is still appropriate compared with the traditional gold standards mentioned earlier that have proven track records.

The first podium presentation shared the findings of a systematic review and meta-analysis of MS versus midurethral slings [5]. Only nine MS studies, totaling 758 women, were available. They were primarily single-center studies, with limited follow-up using a primary outcome of clinical cure/improvement at 6 months, and with approximately 10% of patients lost to follow-up. The success rate was lower and the repeat continence surgery higher in the MS group. A possible explanation for these globally disappointing results may be related to reduced anchoring and support. Admittedly, the dataset is limited, but the early differences discovered between patient-reported and objective cure rates is concerning. A second presentation originated from a group that championed the TVT under local anesthesia [6] and compared it to the more recent TOT.

Both techniques resulted in equally good results in their very experienced hands; however, during the discussion it became clear that the follow-up evaluation was carried out by the same assessor not blinded to the original procedure, which represents a potential bias. Although very committed to the TVT from its inception, these authors indicated a shift in their approach based on the results of their study, as they now recommend the TOT as their primary procedure because they found it easier to teach. In the words of one of the commentators after the presentation was over, “a third study did what the company should have done at the onset, namely a three-arm trial comparing TOT with two versions of the MS.” Already at 3 months follow-up, the results (subjective and objective cure rates) in the two MS groups were identical, but much lower than in the TOT group. Their results corroborated the findings of the prior presentation on the meta-analysis of MS versus midurethral slings (mentioned earlier). No comment was made on which procedure to offer a patient with persistent or recurrent SUI after a failed MS because that information was lacking from the reviewed studies.

A recent trial from the Pelvic Floor Disorder Network (PFDN), called the OPUS trial, reported on a group of women with symptomatic pelvic organ prolapse (POP) and no SUI, who were randomized to receive a TVT or sham incisions [7]. At 12 months, those who underwent the TVT had a lower rate of SUI than those in the sham group. However, of the 40% in the sham group with secondary SUI, only 10% underwent an SUI procedure, leading the authors to conclude that some patients will experience SUI after prolapse repair, but few will be sufficiently bothered by it to undergo an additional anti-SUI procedure. In essence, they found no need to recommend for a prophylactic TVT placement at the time of POP repair. Furthermore, perioperative complications occurred in a subset of patients in the TVT group. Thus, patients need to be informed of the risk of unmasking SUI after POP repair. A TVT can always be carried out if needed postoperatively. A pessary trial for a few weeks ahead of the prolapse repair procedure was suggested by one of the participants, and may be a way of determining if once the vaginal prolapse is reduced, whether or not SUI will occur postoperatively. Nonetheless, this is not an absolute method, nor is there an absolutely perfect prolapse-reducing testing procedure to date to determine this risk ahead of time.

A review of recruitment goals in randomized control trials revealed a 40% rate of under-recruitment in contemporary trials on urinary incontinence and POP. The authors looked at their yield of patient recruitment by means of traditional techniques versus targeted Facebook™ advertisements. Ultimately, they were successful with internet-based recruitment both in terms of efficiency and a lower withdrawal rate. They suspected that patients who search online for treatment solutions may be more motivated than those who hear about a given study through their referring physician or gynecologist, or any other advertisement means (e.g., newsletter, radio advertisement or pamphlets). Certainly, there is a cost related to internet advertisement, but they noted a gain in time and personnel, and an overall faster recruitment time, which did offset this modest expense [8].

In summary, newer techniques to correct SUI are not always better than more established procedures. The current process by which to assess a novel procedure should require more scrutiny and well-designed randomized control trials before a newer procedure is disseminated to the general public. However, there are no current restrictions on the rapid adoption of newer procedures before critical information on their cure rate, complications and their management, or the prospect of success from a secondary procedure in case of failure of this given operation are better known. Women with bothersome SUI wishing for surgical correction should review the US FDA public notification guidelines from October 2008 [101] before their consultation, and should expect a thorough discussion with their surgeon about the advantages and disadvantages of the corrective procedure offered to them, especially when a synthetic tape is under consideration. It is my observation that women seen with suburethral tape complications seldom report adherence to these FDA guidelines. SUI is a quality of life condition for which no perfect treatment with 100% result exists at present. Most studies report variable complication rates and failure rates (10–25%, or even higher), the latter depending on outcome tools chosen, duration of follow-up and the rate of patients lost to follow-up [9]. Some complications are serious, life-altering and not always correctable [102]. These International Continence Society (ICS) presentations and the comments by several attendees reminded us all of these above concerns.

This brief and focused overview of the ICS Glasgow Meeting has left several untouched subjects, such as male incontinence, hundreds of posters covering a wide range of basic science and clinical research, and a large interplay of courses and video presentations. One final note relates to the ethical debate presented on the last day of the meeting. With the advent of another FDA notification in July 2011 [102], related to the complications of vaginal mesh procedures to correct POP, came the ethical issue of disclosure from speakers and commentators in the audience who may also have an undeclared bias in this matter. As presented by Brubaker in her webcast address on the last day of the meeting, the word conflict of interest has a fighting connotation and is not very precise [10]. The core issue is what she termed the ‘conflict of risk’, namely that the data presented can be influenced by some existing or former bias that could be related to financial gains, hope for professional advancement and gain in reputation, among others. This conflict of interest exists everywhere. For example, the NIH has recently lowered the financial cap for reporting funding from US$10,000 in 1995 to US$5,000 in 2011, and has asked funded recipients to transparently address any travel reimbursement matters, including purpose of their trip, sponsorship, destination and duration. Conflict of interest also affects medical journal reporting as some articles are more likely than others to lead to reprint requests, thus directly benefiting that journal. Industry is also concerned by remaining credible and transparent in this process. They wish to maintain public trust in their data and publications, and they want to dispel any public perception that some physicians have been ‘bought’ by them to report favorably on their findings. Solutions to this complicated problem are underway as ICS has been at the forefront of standardization processes and hopes to remain a leader in this ethical debate as well.