Several kinds of storage symptoms, including frequency, urgency, and urgency urinary incontinence (UUI), can accompany stress urinary incontinence (SUI). Surgical correction of SUI can improve concurrent overactive bladder (OAB) symptoms such as urgency and UUI. Hovewer de novo urgency and UUI are observed in some patients with no previous evidence of storage symptoms after anti-incontinence surgery.The primary aim of this study was to evaluate the prevalence and severity of de novo or resolved urgency and UUI after midurethral sling surgery. The secondary aim was to determine the predictive factors for postoperative de novo urgency and UUI in SUI

This was a prospective study on female patients with SUI underwent “out -in” trans obturator tape (TOT) from 2002 to 2015 .Exclusion criteria were as follows: comorbidities such as diabetes or neurologic disease; the presence of POP stage II or greater. Preoperative evaluation included: urogynecologic history; pelvic examination using the POP-Q classification; standardized cough stress test performed in the standing position at a bladder volume of 300 mL,urodynamic study and transperineal ultrasound. TOT surgery was performed by an expert surgeon.Follow-up visits were scheduled for 1 month, 6 months,1 year, then annually, by the same preoperative protocol. Statistical analysis was performed by using IBM SPSS statistics software, version 21.0 (IBM Corp., Armonk, NY, USA). Results were considered significant if the p-value was <0.05. We used Student's t-test and chi-square analysis. Logistic regression analysis was used to demonstrate risk factors for de novo urgency, UUI.The study was approved by local ethical committee .The informed consent was obtained from all patients.

A total of 359 patients (mean age, 58.9±11 years) were included in the study. The mean time of symptom evaluation was 155±85 months. Overall, 70 patients had pure SUI, 110 had concurrent OAB dry, and 179 had MUI. Table 1 showed the baseline demographic and clinic data of the patients in three groups.
Patients in the MUI group were significantly older than those in the pure SUI group (60.5±10.55 vs 58.83±10.96, p=0.004). The MUI group had a higher body mass index (BMI, 27.3±4.6 vs 25.82±3.7, p=0.002) and tended to be more overweight (BMI ≥25 kg/m2, 31.8%) than the patients in the pure SUI group (22.8%). There was no significant difference in demographics between the pure SUI and the SUI with urgency groups. In the pure SUI group the success rate was 86%, de novo urgency developed in 22 (31.4%) patients. The severity of urgency was tolerable in 16 patients; only 6 patients required medical treatment. Six patients developed urgency 4 years after surgery; six immediately after the surgical procedure; ten patients between 6 months and 2 years. Six patients with early de novo urgency had not voiding symptoms.In the SUI with urgency group, the success rate was 81%, de novo UUI developed in 23 patients (20.9%), of these 16% after 4 years. Sixtyeight patients (62.3%) had resolved urgency. In those with persistent urgency (38.1%), the subjective severity of urgency was improved in 27, the same in 10, and aggravated in 5. In the MUI group the success rate was 78%, and after the operation, 111 patients (62%) had resolved UUI, with resolved urgency in 75 (41.8%) and remnant urgency in 27 (15%). In patients with residual urgency, symptoms were improved in 24 and the same in 3. Sisixtyeight patients (37.9%) had persistent UUI . Among them, the degree of urgency was improved in 55, the same in 4, and aggravated in 13. Table 2 showed that the BMI≥25 kg/m2,age > 60 years, detrusor overactivity during preoperative urodynamic test were risk factors for de novo urgency in patients with pure SUI, and for de novo UUI in patients with SUI and OAB dry. Furthermore, the previous use of anticholinergics in the preoperative phase could favor the onset of incontinence after surgery.

Our results are in agreement with the literature. In literature the reported incidence of de novo OAB ranged from 1.7% to 42%.Kulseng-Hanssen et al showed that de novo UUI increased significantly from 4.1% 6-12 months  after surgery to 14.9% at 10 years follow-up. A possible explanation for the late occurrence of OAB symptoms might be formation of fibrosis around the sling. Obviously, these symptoms could also be the result of ageing, since the prevalence of OAB increases with age. Women who have predominant urgency component will have worse outcomes after surgery. On the other hand infact a history of anticholinergic medication use has also been addressed as a predictive factor for postoperative OAB wet.Concomitant preoperative UUI was also associated with higher failure rates for SUI specific outcomes. It is possible that patients with mixed incontinence have a higher disease severity or even different pathophysiology than patients with pure SUI

The success rate was higher in patients who have pure SUI. Post-surgery urgency probably occured for causes not related to the surgical procedure. Risk factors were aging, obesity, preoperative detrusor overactivity and  previous use of anticholinergics. Knowing the risk factors is important for good counselling.