Hypothesis / aims of study
There is an ongoing debate on correcting stress urinary incontinence (SUI) at the time of pelvic organ prolapse (POP) repair versus observing until after the repair to see if SUI develops [1]. Urodynamic studies (UDS) with POP reduction have been proposed to unmask SUI to aid in patient counselling and surgical planning [2]. Since our experience is that pre-operative UDS is unreliable and the continence mechanism is difficult to assess in the presence of an anterior compartment prolapse (ACP) stage 2 or more, we have chosen to repair the POP without addressing SUI whether present or occult pre-operatively. The aim of this study was to evaluate UDS findings compared to post-POP continence status after POP repair alone.
Study design, materials and methods
Following IRB approval, a retrospective review of POP studied with UDS prior to POP repair with 6 months minimum follow-up after POP repair was performed. All women had ACP stage 2 or greater, with varying involvement of other compartments. Pre-procedural UDS were recorded for SUI findings, with and without vaginal packing. Packing was performed with a lubricated gauze pack about 10 cm wide placed in the vagina to reduce the cystocele. Patients were followed to determine if subsequent SUI developed based on patient self-report, UDI-6 questionnaires and need for secondary SUI corrective surgery. Groups were separated based on the presence of a prior bladder neck suspension (BNS) surgery for SUI. Primary outcome was the need for a secondary operation. Secondary outcomes were self-reported SUI and UDI-6 questionnaire responses at their most recent visit after POP repair.
Results
From 2015 to 2020, 96 patients were studied (no prior BNS: 77; prior BNS: 19) (Table 1). Median age for the women was 66 years (IQR 62-71.5) and median follow-up was 2.6 years (IQR 1.5-4.7). The most common repair type was anterior vaginal wall suspension (AVWS) (70%). Of those who underwent AVWS, more had no prior BNS (59/67 vs 8/67, p = 0.0074). In total, 9 (9%) of patients had self-reported SUI after POP repair and 19% of those with a completed UDI- 6 answered positively on the questionnaire for SUI (UDI-6, Q 3). Only 2 (2%) underwent a secondary SUI operation.
Of the patients who had SUI with packing on UDS, 3/21 (14%) self-reported SUI after cystocele repair and 2/16 (13%) with UDI answered positively to SUI. Of the patients without SUI on UDS with packing, 7/75 (9%) had self-reported SUI after cystocele repair and 13/61 (21%) with UDI-6 answered positively to SUI. Of the patients who had SUI without packing on UDS, 2/26 (8%) self-reported SUI after cystocele repair and 4/19 (21%) with UDI-6 answered positively to SUI. Of the patients without SUI on UDS without packing, 6/70 (9%) had self-reported SUI after cystocele repair and 11/58 (19%) with UDI answered positively to SUI. Only 4 (44%) of the 9 patients with self-reported SUI after ACP repair and 1 (50%) of the 2 patients that needed a secondary SUI operation had SUI on UDS with or without packing.
Interpretation of results
Given the mixed results shown with UDS in the past, our institution still obtains UDS before POP repair but performs ACP repairs without a concomitant SUI procedure regardless of the UDS findings and monitors the patients for subsequent developing SUI. During the post-operative follow-up period, few women reported SUI and very few required an SUI operation, neither of which were well predicted by pre-op UDS. The only difference between groups based on prior BNS was that women who received AVWS were more likely to not have a prior BNS. This was unsurprising as recurrent prolapse is often treated with mesh sacrocolpopexy as compared to primary prolapse which commonly involves a vaginal approach utilizing uterosacral ligament fixation.
UDS did not prove to be effective at predicting SUI in these women, whether with or without vaginal packing. Very few of those with SUI during pre-operative UDS developed self-reported SUI post-operatively or needed a secondary SUI operation. In addition to the ineffectiveness of UDS in predicting post-repair SUI, few patients overall developed SUI and even fewer required an operation. Of those that developed SUI or had a subsequent repair, most did not show SUI on pre-operative UDS and, therefore, would not have received an SUI operation at the time of POP repair based on recommendations from previous studies [2]. The OPUS trial found that the number needed to treat with an SUI procedure concomitantly with POP repair to prevent one case of post-repair SUI was 6.3 [3]. Our findings support this trial’s main observation.