Hypothesis / aims of study
Studies (1,2) indicate a potential role for low-intensity extracorporeal shock-wave therapy (LiESWT) for stress urinary incontinence (SUI). Our objective was to assess tolerability, safety and efficacy of LiESWT for the treatment of mild to moderate SUI, using a novel trans-vaginal probe targeted at addressing the peri-urethral tissue.
Study design, materials and methods
In this single-blind, randomized-controlled trial, women with mild to moderate SUI were recruited. Following IRB approval and signed informed consent, participants were randomly assigned to either LiESWT with 0.1 mJ/mm2 intensity, 1600 pulses, twice weekly for 4 weeks, or sham treatment, without energy transmission. Both were administered by a vaginal probe (MoreNovaFEM, Hikkonu Medical Systems Ltd, Ramat Hasharon, Israel), designed to deliver the pulses towards the peri-urethral tissue. In the treatment arm, LiESWT was delivered for a total of 16 minutes towards 4 points below the urethra, by rotating the probe every 4 minutes by approximately 20 degrees. The same procedure was carried out in the sham arm using an identical probe producing the same sound of the treatment probe. Inclusion criteria were age 20-75, SUI diagnosis according to history and positive cough-stress test, functional bladder capacity > 350 cc, post-void residual urine < 50 cc. Exclusion criteria were pregnancy or breastfeeding; severe SUI (1-hour pad test >50 grams); pelvic organ prolapse beyond the hymen; mixed urinary incontinence with a predominant urgency component (UDI-6 questions 1 or 2 scoring 3 or 4); past history of vaginal fistula; perineal tear grade 4; current history of chronic pelvic pain; genito-pelvic pain penetration disorder; genital HSV; active STI; inflammatory bowel disease; psychiatric conditions preventing the ability to provide informed consent; medical treatment affecting bladder function. Efficacy was evaluated at 1 month and 6 months following treatment completion using the Patient Global Impression of Improvement (PGI-I); the International Consultation on Incontinence Questionnaire, Short Form (ICI-Q-SF); the Urinary Distress Inventory (UDI-6), the Incontinence Impact Questionnaire (IIQ-7); cough-stress test; 1-hour pad test. SF was evaluated by the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire, IUGA-Revised (PISQ-IR).
Results
Thirty-nine women were screened between June 2022 and June 2023. Four women were excluded at screening (1 patient: recurrent vulvovaginal candidiasis; 1 patient: inflammatory bowel disease; 1 patient: recurrent genital HSV; 1 patient: residual urine volume >50 cc). Following recruitment, 2 patients dropped out before initiating treatment, due to personal issues. Four patients dropped out before completion of 8 treatment sessions due to mild adverse events (1 patient: dyspepsia after session 2; 1 patient: bacterial vaginosis after session 3; 2 patients: UTI following 4 and 6 sessions, respectively). Three participants were lost to follow-up after 4-7 sessions, due to personal reasons preventing them to comply with the treatment schedule. Twenty-seven women who completed 8 treatment sessions were included in final analysis: 18 in the study group and 9 in the control group. Age was 50.1±8.6 vs 46.4±9.8 (p=0.34) and BMI was 25.1±3.7 vs 27.3±4.4 (p=0.17), respectively. Two women had diabetes mellitus in the treatment group vs none in the sham group (p=0.53). Median parity was 3.0 (2.0–3.0) in both groups (p= 0.80). Seven (38.9%) women in the study group and 4 (44.4%) in the sham group were post-menopausal (p=1.0). Treatment sessions were well tolerated: reported pain visual analogue scale (VAS) at treatment n. 8 on a scale of 1-10 was 0.6±1.0 in the treatment group and 0.1±0.3, in the sham group, p= 0.21. At one month follow-up, the only significant difference between treatment and sham was that improvement in IIQ-7 scores was significantly greater in the study group (-15.9±25.8 vs -1.0±7.3, p= 0.02). This change was sustained 6 months following treatment: -15.6±23.9 vs -3.1±9.6, p=0.04 (Figure 1). At 6 months, we also observed a greater improvement in the one-hour pad test in the treatment group, with borderline statistical significance: -1.9±3.8 grams vs. 0.5±3.5 grams in the treatment and sham groups, respectively (p=0.055). Changes in urinary and sexual function were otherwise similar between groups (Figure 2). Possible procedure-related adverse events were mild and patients fully recovered: spotting (2 women, study group), UTI (1- study group, 1- sham), bacterial vaginosis (1- study group).
Interpretation of results
To our knowledge, this is the first study assessing delivery of LiESWT by a vaginal probe for SUI. We have shown this approach is feasible and well tolerated by women, causing only mild discomfort and no significant pain. The treatment has proved safe on 6-months follow-up, with few and mild procedure-related adverse events. At the 6-months follow-up, we observed a greater improvement in the amount of urine leakage in the treatment arm, assessed by the 1-hour pad test. We also observed a greater improvement in the impact of SUI on quality of life in the treatment arm 1 month and 6 months following treatment completion, as reflected by a significant decrease in IIQ-7 scores.