Urogynaecology: Effect of tension-free vaginal tape in women with a urodynamic diagnosis of idiopathic detrusor overactivity and stress incontinence
Mr JRA Duckett, Medway Maritime Hospital, Windmill Road, Gillingham, Kent, UK.
Objective To determine the effect of tension-free vaginal tape (TVT) in women with idiopathic detrusor overactivity (DO) and urodynamic stress incontinence (USI) and to propose appropriate pre-operative counselling based on this information.
Design Retrospective cohort study.
Setting Urogynaecology Unit, District General Hospital, Kent.
Population Fifty-one women (from a total of 344 women undergoing TVT) with urodynamic evidence of both DO and USI who underwent TVT insertion between November 1999 and March 2003.
Methods Women with more than six-month follow up were assessed objectively with cystometry. Subjective results were assessed using structured interview and condition specific Kings Quality of Life Questionnaire.
Main outcome measures Objective resolution of DO and subjective absence of urge syndrome after TVT. Cure of USI was the secondary outcome measure analysed. The effect of drug therapy on residual urge symptoms was assessed.
Results Objective cure of DO was demonstrated in 47% and subjective cure of urge symptoms in 63%. In women with persistent urge symptoms, the addition of anticholinergic medication resulted in resolution of urge incontinence in a further 22% of women. USI was objectively cured in 92%.
Conclusions More than 60% of women diagnosed urodynamically with DO and USI experience complete resolution of urge symptoms following TVT. Further symptom improvement can be achieved with additional anticholinergic medication.
The tension-free vaginal tape (TVT) was first reported in 1996 for the treatment of urodynamic stress incontinence (USI).1 Currently, this is the most commonly employed operation for urinary incontinence in the UK. A prospective randomised controlled trial has shown an objective cure rate of 66%.2 Long term studies (five years) have suggested a cure rate for USI of 90%.3
The incidence of mixed urinary incontinence has been reported variously as ranging from 30% to 50%.4 Women with idiopathic detrusor overactivity (DO) and USI (‘mixed incontinence’) are a challenging group to treat. Very little has been published regarding the surgical treatment of women with both DO and USI. Physiotherapy may help both conditions. Anticholinergics may be targeted at relieving irritable bladder symptoms. Difficulty arises when physiotherapy and anticholinergics fail to provide symptom relief. There is debate regarding whether the DO should be treated prior to the USI or vice versa. Coexisting DO is known to be associated with failed surgery for stress incontinence.5 Colposuspension has long been considered the gold standard surgical treatment of USI but some women can have persistent or even worsened urge symptoms after surgery. TVT is reported to have a low incidence of de novo urge symptoms.3
Women with USI but mixed urinary symptoms have been evaluated after TVT but women with DO have been excluded from surgery.6 When assessing women after surgery, the history is unreliable in differentiating between USI and DO.7 Evaluation with cystometry is necessary to differentiate between the causes of residual filling symptoms and also to exclude voiding abnormalities which may present with irritable symptoms. To our knowledge, no previous study has exclusively looked at women with urodynamic evidence of DO and USI treated with TVT.
The purposes of this study were to objectively assess the resolution of DO; to determine the cure rate of urgency and urge incontinence after TVT; and to provide appropriate pre-operative counselling for patients with mixed DO and USI based on this information. We also wanted to identify whether persistent irritative symptoms were controlled with anticholinergic medication.
Subjects were selected from 344 women who underwent TVT in the hospital from November 1999 to March 2003. Clinical records of the women were retrospectively reviewed. Exclusion criteria included women with neurological disorders, previous surgery for incontinence, voiding abnormalities, bladder pathology identified on cystoscopy and those with additional surgical procedures combined with TVT. Fifty-one women, who had symptoms of both stress and urge incontinence and were proven to have idiopathic DO and USI on urodynamics, undergo regular review.
All women in the study group had a detailed urogynae-cological history, physical examination and urodynamic studies (filling and voiding cystometry) pre-operatively.
Pre-operatively, a combination treatment was offered. All women were given advice regarding fluid intake. Anticholinergic medication was used for DO. A physiotherapist taught pelvic floor exercises. Women with persistent symptoms of stress incontinence, after treatment with anticholinergics and physiotherapy, were offered surgical intervention. A similar strategy of treating DO prior to offering surgery is reported by 73% of surgeons performing colposuspension.8 The TVT procedure was performed as described by Ulmsten et al.1 and spinal anaesthesia was used. Cystoscopy was normal in all women.
Post-operatively, all women had clinical evaluation at six weeks by history and examination. At the second follow up clinic (more than six months after the surgery), patients had a repeat clinical evaluation. Assessment of the 13 women on anticholinergic medication was performed after stopping the medication for four weeks.
Patients perception of changes in their symptom was assessed, more than six months post-operatively, by interview and using the condition specific King's Quality of Life Questionnaire. A number of urinary tract symptoms form an integral part of the King's Quality of Life Questionnaire.9 Objective assessment was performed by medium fill dual channel subtracted cystometry and pressure/flow voiding studies. The residual urine volume was measured with a bladder scanner after free flow voiding.
The primary outcome measures were objective cure of DO, based on a normal detrusor function during filling cystometry and subjective cure of overactive bladder symptoms from interview and questionnaire. Subjective resolution of urge syndrome was defined by absence of urge symptoms without pharmacological therapy. Women with a history of urgency and urge incontinence, if occurring more than once a month, were classified as persistent urge syndrome. The secondary outcome measure was the absence of stress incontinence on cystometry.
All definitions of symptoms, signs and urodynamic observations used in the study confirm to the terminology recommended by the International Continence Society.10 All women gave informed consent. The chairman of the Ethics committee reviewed the study. Data are presented as median [range] or n (%).
Fifty-one women were included in the study. The median age of the women was 52 (34–82) and the median parity was 2 (0–4). The median (range) follow up time was 12 (6–26) months, and all women had completed at least six-month follow up. All women had stress incontinence symptoms and symptoms of urge syndrome (urgency/frequency/nocturia) with or without urge incontinence. Forty-seven women (92%) of women had urge incontinence 48 (94%) had urgency and 30 (59%) had frequency and nocturia.
Fifty women (98%) received anticholinergic medication pre-operatively. One patient decided not to take anticholinergic medication. Thirty-seven women were treated with tolterodine, five with imipramine, one with propiverine, three with oxybutynin and four were on two or more anticholinergic medications. Thirty-one women (61%) stopped the medication pre-operatively because of side effects or lack of efficacy. Fifteen women (29%) stopped the medication post-operatively between day one and week six. Four women continued the medication after six weeks. Nine women (18%) had restarted the anticholinergic medication after the 6-week follow up visit for persistent or recurrent urge symptoms.
Five women (10%) subjects failed to attend the follow up clinic after six months. The remaining 46 patients formed the study group with follow up of more than six months, of whom 36 agreed to have repeat urodynamics for objective assessment of DO.
1Table 1 shows subjective and objective outcome data after six months. Of the 17 women who complained of urge incontinence, 6 (35%) had terminal DO, 6 (35%) had phasic DO, 4 (24%) had normal detrusor function and 1 declined cystometry. Eighty-six percent of women did not perceive their urge symptoms as troublesome.
Table 1. Subjective and urodynamic assessment after six months. Subjective data on 46 women (upper panel) and urodynamic data on 36 women (lower panel). Data are presented as n (%)
|Overactive bladder symptoms||17 (37)||29 (63)|
|Stress incontinence||4(9)||42 (91)|
|DO||19 (53)||17 (47)|
|USI||3 (8)||33 (92)|
The symptoms reported at the six-week visit differed from the symptoms reported at their six-month review in seven cases, where urge incontinence was not reported at the initial post-operative visit but was recorded at the second review. One woman did not have stress incontinence at the first visit but had developed recurrent symptoms (after a severe bout of coughing) by the second visit.
Of the 10 women who declined cystometry, 1 had irritable symptoms. None of the 10 women who declined cystometry complained of stress incontinence.
The general health perception, incontinence impact and symptom scores of the King's Quality of Life Questionnaire were used for measuring the quality of life (QOL) after TVT. Thirty-seven of the 46 (80%) showed low scores on incontinence impact and symptom severity measures in the King's Quality of Life Questionnaire.
The 17 women with persistent urge symptoms were offered or restarted on anticholinergic medication. Four women declined any medication as they did not perceive the urge symptoms to be problematic. Ten of the 13 women (77%) who did restart medication reported cure of urge incontinence and wished to continue with the medication.
This series suggests that in women with combined USI and DO treated with TVT, the objective cure of DO is 47% and the subjective cure of urge syndrome is 63%. The addition of post-operative anticholinergic medication further enhances the cure rate resulting in 85% of these women having no stress or urge incontinence. Post-operative bladder overactive symptoms did not seem to be obstructive in origin as the maximum flow rates were not significantly different in those with DO compared with those with normal detrusor function (data not shown). Persistent urgency and/or DO following continence surgery is known to reduce patient satisfaction.11 In spite of 37% of women having persistent overactive bladder symptoms, 80% did not perceive the urge symptoms as troublesome. Ideally, these women should have completed the Kings questionnaire pre-operatively with measures of patient global impression of severity and improvement questionnaires. We recognise that some of the benefit may have been due to the equivalent of the placebo effect, seen in many trials investigating DO. It is possible that the women found the reduction in the incontinence episodes to be of such benefit that they were less worried about the urgency. Women with persistent urge symptoms or DO resistant to drug therapy have been offered further investigation to exclude tape migration and chronic cystitis.
A literature review on Pubmed (search using TVT) failed to identify any other study only assessing TVT in women with DO and USI. This retrospective observational study has several limitations. The population size was small but this is an uncommon clinical scenario occurring in only 15% of our TVT procedures in a 29-month period. Although this study is retrospective, all the initial data were collected prospectively as part of an ongoing departmental audit. Data are collected at the time of surgery with further checks at the post-operative visit and via theatre registers. We do not feel that there is bias, related to lost/missed women who might have different outcomes. A prospective study would be ideal to confirm the results. The follow up period was relatively short but averaged one year. Only 78% (36/46) of our subjects agreed to undergo a six month (or latter) cystometry assessment.
After the initial six-week visit, 16% of women developed recurrent urge incontinence before their second visit. We were unable to follow up five of the initial 51 women identified but it is unlikely that the non-attenders would have significantly affected the overall results of the study. We would recommend that these women are followed-up for the longer term as symptoms may change with time.
The extensive data on TVT procedure state a cure rate for stress incontinence of between 66% and 90%.1–3 The results regarding stress incontinence in our study follows the same trend. The 63% cure rate of urge incontinence in this study is consistent with other reported series for resolution of urge symptoms following anti-incontinence procedures, although these studies do not all include women with DO.2,4,6,12,13 Previous studies of TVT that included some women with DO did not report the objective post-operative urodynamic results.6,13 In the study by Rezapour and Ulmsten,6 the subjective cure of urge incontinence was reported in 85% of women. Twenty-eight percent of the cured or improved group had persistent urgency but we do not know if they had persistent DO. This study is not directly comparable as women with significant DO were excluded from surgery and the diagnosis of DO did not correspond to conventional terminology.10 Similarly the study by Deval et al.13 did not report the post-operative urodynamic results regarding DO. Neither study reported pre- and post-operative treatment regimes and whether additional anticholinergic medication was useful. We used strict criteria to assess cure of overactive bladder symptoms post-operatively. Improvement of symptoms was not assessed separately. Women with occasional urgency and urge incontinence more than once a month were classified as persistent urge syndrome.
DO has long been considered a disease of the detrusor muscle and/or nerves. This study raises the issue that in some women the abnormality may lie in the urethra. Possibly the exact placement and tension of the TVT may be important in the resolution of irritable symptoms. We are currently evaluating tape position by transperineal ultrasound to test this theory.
This study describes the results that can be achieved with a combination of surgery and anticholinergic medication in a group of women who have failed to respond to conservative therapies. However, many women responded to conservative therapies and these results should not be used as evidence that women with DO and USI should be treated primarily with surgery. We are now able to counsel women that after a TVT 63% will no longer need anticholinergics and will have a cure of their urinary symptoms. Another 22% will achieve symptom control with medication.
The authors would like to thank Mrs Maria Eaton, the continence nurse, for her help in completing the study.