Complications of Synthetic Midurethral Slings: Is There a Relevant Discrepancy Between Observational Data and Clinical Trials?

CONTEXT

The complications of synthetic midurethral slings (MUSs) in women with stress urinary incontinence (SUI) have become a globally debated issue.

OBJECTIVE

To systematically review the short- and long-term complications of mesh slings reported in observational data compared with clinical trial data, to determine whether the complication rates from clinical trials reflects "real-world" observational data.

EVIDENCE ACQUISITION

PubMed and Cochrane Library were searched. Methods as detailed in Preferred Reporting Items for Systematic Reviews and Meta-analyses and Cochrane Handbook for Systematic Reviews of Interventions were followed.

EVIDENCE SYNTHESIS

Thirty registries/databases including 709 335 MUS procedures (1-22 yr of follow-up) were identified. MUS procedures were associated with intraoperative bladder perforation in 0.86-3.6%, urethral perforation in 0-0.1%, vascular injury in 0.04-0.1%, voiding lower urinary tract symptoms (LUTS) in 1.47-3.5%, vaginal exposure in 0.2-1.9%, and reoperation in up to 9% of cases. Forty-three randomised clinical trials were identified, including 6284 women who underwent MUS procedures and 2177 women who underwent other interventions (1-10 yr of follow-up). MUS procedures were associated with urinary tract perforation in 2.58%, vaginal injury in 1.43%, de novo voiding LUTS in 4.37%, de novo storage LUTS in 5.41%, mesh extrusion/exposure (vaginal/urinary tract) in 2.54%, dyspareunia in 2.26%, pain (pelvic/suprapubic/perineal) in 2.83%, and reoperation for complications required in 1.82% of cases. Meta-analyses of the randomised controlled trials revealed that retropubic MUSs were associated with more events of urinary tract perforation (risk ratio [RR] 9.81, 95% confidence interval [CI] 5.05-19.04, high certainty of evidence [COE]) and voiding LUTS (RR 1.57, 95% CI 1.19-2.07, high COE) than transobturator MUSs. MUSs were associated with more events of pain than mini-slings (RR 1.72, 95% CI 1.04-2.87, moderate COE).

CONCLUSIONS

Short- and long-term data on complications of polypropylene mesh used for female SUI are fairly comparable when using outcome data from well-designed clinical trials or from less structured prospective or retrospective registries. Comparisons have to be made with caution since the two systems of data collection are inherently incomparable. This knowledge should be incorporated in the discussion on how to implement polypropylene mesh for female stress incontinence.

PATIENT SUMMARY

In order to know whether mesh tapes used for treating stress incontinence work well and are safe, high-quality information is important. It appears that well-designed clinical studies give similar results to large registration databases. These data should be interpreted with caution in view of the different ways the information was collected. These results will help physicians and patients understand the risks of mesh tapes.

Urgency and pain in patients with overactive bladder and bladder pain syndrome. What are the differences?

BACKGROUND

The Overactive Bladder Syndrome (OAB) and the Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) are different urological conditions sharing 'urgency' as a common symptom. The aim of this review is to address our existing knowledge and establish how these symptoms are interrelated and to determine whether or not there is a common link between both symptoms complexes that help to distinguish one from the other.

METHODS

Pubmed was used to obtain references for this non-systematic review aiming to discuss differences between OAB and BPS/IC. Guidelines of several professional associations and discussions based on expert opinion from the authors were implemented.

RESULTS

Whilst in BPS the hallmark symptom is pain on bladder filling, urgency is the defining symptom of OAB. Whilst it is likely that the pain in BPS/IC arises from local inflammation in the bladder wall, the nature of urgency as a symptom, its origin, and the relationship between urgency and pain, as well as the different afferent mechanisms associated with the genesis of these sensory symptoms, remains unknown. Although the aetiology of both OAB and PBS/IC is unclear, the influence of environmental factors has been suggested. Both are chronic conditions with very variable symptom resolution and response to therapy. The relationship with voiding dysfunction, gynaecological causes of chronic pelvic pain or the possible alteration of the hypothalamic-pituitary-adrenal axis and psychological disorders has not been established. Inflammation has been suggested as the common link between OAB and BPS/IC.

CONCLUSIONS

OAB and BPS/IC are different symptoms complexes that share urgency as a common symptom. None of them have a specific symptom although pain on bladder filling is the hallmark symptom in BPS/IC. Bladder pain with urgency should be a trigger for referral to the provider with appropriate knowledge and expertise in this disease state, whereas the management of OAB should be part of normal routine care in the community.

Detrusor-sphincter dyssynergia

Neurological control of micturition is undertaken by central and peripheral nerve systems through complex neuronal interconnections that are mediated by the action of several neurotransmitters, finally controlling the function of detrusor muscle and external urethral sphincter. In normal circumstances, both muscles must have co-ordinated contractions in such a way that when the detrusor contracts, the external urethral sphincter relaxes. The loss of this co-ordinated action leads to the so-called syndrome of detrusor-sphincter dyssynergia. Without adequate treatment, more than 50% of men with this condition will develop severe complications. There are several neurological diseases that might lead to this condition where a common physiopathology consists of a distortion of the complex neural mechanism innervating the lower urinary tract. Because of this complexity, it is difficult to find a curative treatment providing a definitive solution for a majority of patients. Although most of the currently available therapies only provide partial or temporary solutions, some modalities offer a promising perspective.

Persistence with antimuscarinic therapy in patients with overactive bladder

Overactive bladder (OAB) is a chronic condition, which impacts patients' health and quality of life. The primary symptoms of OAB are distressing and may interfere with work, psychosocial and sexual functioning. OAB also is associated with increased risk of urinary tract infections, fractures from falls, skin infections and depression. Patient's concerns about the effects of incontinence on lifestyle highlight the need to restore continence. The mainstay of treatment is antimuscarinic drug therapy, which may often produce only modest reductions in OAB symptoms and may be accompanied by bothersome adverse effects, leading to poor adherence to prescribed medications. Successful treatment of OAB depends on persistence with the prescribed medication, and efficacy and tolerability are key influencers of persistence. New antimuscarinic agents are now available for treating OAB that significantly improve symptoms of incontinence, urgency and frequency with few adverse effects. An improved efficacy and tolerability profile should result in greater patient satisfaction and persistence with therapy during long-term therapy.

Influence of preoperative bladder capacity and compliance on the outcome of artificial sphincter implantation in patients with neurogenic sphincter incompetence

We performed a retrospective study of 23 patients with neurogenic sphincteric incompetence who had undergone implantation of an artificial urinary sphincter to determine if bladder capacity and compliance as determined by cystometrography could predict the need for enterocystoplasty. Study criteria were neurogenic sphincteric incompetence, no previous operations on the lower urinary tract, and performance of preoperative and postoperative cystometrography. Patients were 5 to 17 years old at implantation. Incontinence was caused by myelomeningocele (18 patients), sacral agenesis (3) and spinal cord tumor (2). The 8 patients for whom preoperative cystometric bladder capacity was greater than 60% of the expected capacity for age have been followed for a mean of 60 months. All 8 patients are continent and none required enterocystoplasty. Preoperative bladder compliance exceeded 2 ml./cm. water in all patients (group 1). Of the 15 patients for whom preoperative cystometric bladder capacity was less than 60% of the expected value (group 2, small bladders) 8 followed an average of 72 months had a compliance greater than 2 ml./cm. water and have done well without bladder augmentation. In contrast, 7 patients in this group (46%) required enterocystoplasty: 6 for persistent or recurrent incontinence and 1 for upper tract changes. The average interval between artificial sphincter placement and enterocystoplasty was 14 months. Patients with a small bladder that required augmentation had a preoperative bladder compliance of less than 2 ml./cm. water. We conclude that small bladder capacity, as determined by cystometrography in patients with neurogenic sphincteric incompetence but a bladder compliance of less than 2 ml./cm. water predicts the future need for bladder augmentation. In all other patients, with good medical treatment and followup, the possible adverse effects of a small capacity bladder can be prevented or corrected. With this strategy we have been able to avoid enterocystoplasty with its attending potential complications in 70% of our patients with neurogenic incontinence and favorable urodynamics regardless of preoperative cystometric bladder capacity.

The influence of urinary diversion on experimental gastrocystoplasty

Gastrocystoplasty is used to augment the bladder of patients with decreased renal function to prevent development or worsening of metabolic acidosis. We recently observed a perforated peptic ulcer in the gastric portion of a defunctionalized gastrocystoplasty. We postulated that the lack of buffering action of urine precipitated peptic ulcer disease in the gastrocystoplasty. To explore this possibility further, we conducted an experiment. In 12 adult female mongrel dogs (weight 15 to 26 kg.) the bladder was divided into right and left segments. One kidney was removed and both hemibladders were capped with a vascularized segment of gastric body. Thus, 1 side (wet) remained exposed to urine, while the other side (dry) was drained to the abdominal wall with a cystostomy tube. The animals were divided into 2 groups: 9 in group 1 received no drugs to modify gastric secretion and 3 in group 2 received a hydrogen (H2) blocker. Three animals in group 1 had perforation of the vesical part of the dry gastrocystoplasty 2 to 3 weeks postoperatively and were sacrificed. The others were sacrificed 3 to 6 weeks postoperatively. Serum gastrin levels remained normal in all animals. Gross and histological examinations of the augmented bladders in group 1 revealed ulcerations of the bladder segment of the wet and dry gastrocystoplasties but the lesions were more numerous and prominent on the dry side in all animals, particularly those in which the perforations occurred. A peptic ulcer was noted in the gastric portion of the dry gastrocystoplasty in 1 animal. The bladder epithelium of the dry gastrocystoplasty showed glandular metaplasia in several animals in this group. In group 2 the wet gastrocystoplasty showed normal histology except in 1 dog that had mild inflammation and focal superficial ulceration in the vesical portion. On the other hand, the dry gastrocystoplasty showed severe inflammation and ulcerations in 2 animals, and mild inflammation of the vesical portion in 1. There were no perforations in this group. This experiment demonstrates that gastrocystoplasty produces cystitis but that these changes are more prominent in the absence of urine, as indicated by the severity of the lesions, perforations and metaplasia. Peptic ulcer disease occurred in the gastric portion of the dry gastrocystoplasty in 1 animal. The use of H2 blockers decreases the incidence of ulceration in wet gastrocystoplasty but it seems to have less influence on the ulceration of dry gastrocystoplasty. Clinicians must be alerted to the risk of perforation of dry gastrocystoplasty.