Symptoms of IC/BPS have a negative impact on female sexual function.  We aimed to evaluate the effect of intravesical botulinum toxin-A(Btx-A) injection on the improvement of sexual dysfunction and urinary syptoms using the multi domain Female Sexual Function Index(FSFI) questionnaire and interstitial cystitis symptom index (ICSI), and interstitial cystitis problem index(ICPI).

The data of the 23 patients who were diagnosed with refractory IC/BPS and received intravesical Btx-A between January 2015 and December 2019 were retrospectively reviewed in this single-center study. The study group was named “Group 1” and evaluated in two groups as follows: Group 1A (pretreatment scores) and Group 1B (posttreatment scores). Subsequently, 23 age-matched healthy sexually active women without any urinary disease were determined as the control group(Group 2). This group was created by patients who received routine gynecological examinations in the outpatient clinic. As per our protocol, 23 patients who failed to respond to first-line treatments, such as conservative therapies, and second-line treatments, including oral analgesic drugs and intravesical injections of chondroitin sulfate, heparin, and hyaluronic acid, were included in the study group. The surgical procedure was performed by a single surgeon. Here, 100 units of Btx-A were diluted to 20 cc 0.9% saline, and 1 cc was then applied submucosally on 20 different points of the bladder wall using a 25-gauge needle (5 U/1 ml per site). A 14 F urethral Foley catheter was placed after the injection. On the second day after the injection, the catheter was removed, and all patients were discharged. At this point, patients were warned of the need for clean intermittent catheterization if deemed necessary. In the third week after the surgery, uroflowmetry was undertaken and the postvoid residual volume was measured to exclude urinary retention. Next, all patients were asked to fill out validated versions of the FSFI and ICSI (range of 0 to 20) as well as the ICPI (range of 0 to 16), visual analog scale (VAS) for pain assessment, and three-day bladder diary (BD) which were used to assess pre- and post-operative functional bladder capacity and daytime and night urinary frequency. Specifically, the FSFI questionnaire consists of 19 questions that investigate the following six domains: desire, arousal, lubrication, orgasm, pain, and satisfaction. Finally, the mean scores of FSFI, ICSI, ICPI, VAS, and BD data of the study and control groups were compared at baseline and three months after the treatment. Here, the primary endpoint was the assessment of improvement in SD, while the secondary endpoints were the changes in urinary symptoms and pain after the Btx-A injection.

The demographic characteristics of the patients in both groups are displayed in Table 1. Both groups were statistically similar in terms of mean age, parity, and percentage of postmenopausal patients. The mean time between the onset of symptoms and Btx-A injection in Group 1 was 32 ± 5.6 (13–40) months. Moreover, significant lower scores in all domains of FSFI except lubrication during the pretreatment period were shown in patients with IC/BPS compared to the control group. Dyspareunia was described by 17 patients (74%) in the study group compared to seven patients (30%) in the control group. In the third month after surgery, 20 patients had increased FSFI scores, whereas three patients had decreased FSFI scores. The baseline mean total FSFI score increased from 21.53 ± 7.02 to 28.14 ± 7.85 in the postoperative period as compared to the preoperative period in the study group, which was statistically significant (Table 2). As can be seen from Table 3, the improvement in all FSFI domains was statistically significant in the follow-up period as compared to the baseline period.Further, the total FSFI and post-treatment scores in the three domains of desire, lubrication, and pain were similar to those in the control group after the treatment. 
Meanwhile, 20 of the 23 patients showed an improvement in the ICSI and ICPI scores, whereas no improvement was demonstrated in three patients in the postoperative evaluation. Although ICSI and ICPI scores showed statistically significant improvements in the post-treatment period as compared to baseline scores, the posttreatment scores showed no significant difference as compared to the control group. Moreover, 18 patients had a lower VAS score while one patient had a higher VAS score in the postoperative as compared to the pretreatment period. Here, a review revealed no change in the VAS scores in four patients. The preoperative assessment of the mean VAS score was 8.31 ± 1.45, which decreased to 6.52 ± 1.72 in the third follow-up month. Finally, statistically significant improvements were observed with treatment in parameters such as daytime frequency, nighttime frequency, and mean voided volume, which were evaluated using the voiding diary (Table-4).

This is the first study in the current literature about the effect of Btx-A injection on SD in patients with IC/BPS, in addition to its proven effect on the improvement of urinary symptoms. Specifically, we investigated the effect of intravesical Btx-A on different domains of sexual function as the primary endpoint of the study.

Although bladder pain and lower urinary symptoms are prominent in the diagnosis of IC/BPS, the disease is associated with a remarkably high incidence of SD. Further, pelvic and bladder pain appear to be major contributors to the development of SD in IC/BPS patients, yet several factors contribute to the pathogenesis of SD. In addition to improvements in pain and urinary symptoms, significant improvements in sexual function were observed in this study following the intravesical injection of Btx-A in patients with IC/BPS. Intravesical injection of Btx-A also resulted in statistically significant improvements in all aspects of sexual function, including desire, arousal, lubrication, orgasm, pain, and satisfaction. Patients can achieve a similar level of sexual function as the general population with Btx-A injection.

Continence 2S2 (2022) 100455
DOI: 10.1016/j.cont.2022.100455