Hypothesis / aims of study
The prevalence of urinary incontinence in adult women has been estimated to be between 10% to 40%, and is considered severe in about 3% to 17%(1). Transobturator Vaginal Tape Inside-Out was described by De Leval in 2004 (2) and it has been used as a usual technique for the treatment of stress urinary incontinence in current practice of urogynecology.
In most cases, this surgery is successful and patients obtain an improvement in their symptoms and in their quality of life.
Statistical models are being designed to estimate the results of surgery, informing patients before surgical approach (3).
The aim of this study was to identify which factors are associated with better long-term results in quality of life, measured by ICIQ-SF questionnaire, in those patients undergoing this kind of surgery.
Study design, materials and methods
An observational retrospective study was developed between 2005 and 2018. The study population consisted on patients attended in Urogynecology Unit, who were remitted from primary assistance centers for stress urinary incontinence (SUI) and mixed incontinence (MUI).
All of them were previosly interviewed, explored and undertook a urodynamic test before surgery.
A tension-free vaginal tape transobturator - TVTO (I-STOP©) tehnique was placed at all our patients.
Then, they were controlled in our centre at 1 month, 6 months and 1 year after surgery. After clinical discharge, standard telephone queries (ICIQ-SF) were made to them.
The primary endpoint of this study was the quality of life (QoL) after surgery measured by the validated score ICIQ-SF. Moreover, we redefined as a good QoL, patients with ICIQ-SF=0 and with bad results patients with ICIQ-SF different from 0. Variable factors considered are: type of incontinence, age, admission days, urinary catheter day, body mass index (bmi), ICIQ-SF previous, genital prolapse associated, complications: intra-surgery, early post-surgical and late post-surgical and need to sling section.
We register this information in an Access© dababase.
Statistical analyses were performed using the Stata© (Version 14.0. College Station, Texas: StataCorp LLC). Percentages were used to describe categorical variables and means (±sd) were used in continuous ones. Binary and multivariate logistic regression analysis was used to identify independent risk factors associated with quality of life (ICIQ-SF).
Finally, a total of 902 patients were recruited.
Descriptive analysis was described at table 1, in summary: age mean was 58,77 years (+/-11,41), with Oxford Vaginal Testing mean result 1,93 (+/- 3,91), BMI mean 29.45 kg/m2 (+/- 5,10). Their previous Quality of Life (ICIQ-SF) mean was 10,94 (+/- 7,93) and type of incontinence was SUI 456 (50,5%), MUI 401 (44.5%) and hidden 45 (5%). Concomitant surgery of pelvic organ prolapse was done in 350 patients (38.3%). After surgery, quality of life (ICIQ-SF) mean was 3,34 +/- 5,94.
Comparative bivariate analysis indicate that age, BMI, previous type of incontinence and admission days were variables with statistical association to persistence of UI before surgery (p=0.003, p=0.001, p=0.001 and p=0.007, respectively)
Multivariate analysis was peformed looking for a model to predict percentage of risk of CONTINENCE (Good QoL). Table 2 indicate results of our model, were age wasn't included for being a confusion factor and previous surgery resulted a factor to be considered (bivariant analysis indicated p=0.07, and for this reason is included in multivariate model).
Interpretation of results
Antiincontinence surgery using TVT-O has obtained good results, proving an increase in the long-term QoL in these patients. This technique entails a low rate of complications, but for the symptomatic ones a close surveillance is required.
Type of Incontinence, age, days of admission, body mass index and late post-surgical complications have been associated factors influencing QoL in the bivariant analysis.
However, multivariate analysis has shown the confounding effect of some of these parameters and it shown need to added 'previous surgery' to the model.