Prospective, Randomized, Double-blind, Placebo-controlled, Pilot Study of Extracorporeal Shock Wave Therapy for Detrusor Underactivity/Underactive Bladder.

Background: Detrusor underactivity/underactive bladder (DU/UAB) is a disease with great unmet needs and no current approved drug treatment. Extracorporeal shock wave therapy (ESWT) has been shown to improve regeneration of tissue and increase detrusor contractility in preclinical studies of DU/UAB. Objective: To assess ESWT as a treatment of DU/UAB. Design, setting, and participants: Patients with DU/UAB were enrolled in this phase 2 randomized, double-blind, placebo-controlled, physician-initiated study. Intervention: The patients were assigned to ESWT (N = 6, 2500 shocks, frequency of four pulses per second, and maximum total energy flow density of 0.25 mJ/mm ²) once a week for 6 wk at the suprapubic bladder area or to placebo (N = 5, shock wave setting without energy transmission). Outcome measurements and statistical analysis: The primary endpoint was the average changes in postvoid residual urine (PVR) from baseline to 4 wk after treatment. Other endpoints included the average changes in 3-d voiding diary, global response assessment of patient satisfaction, Underactive Bladder Questionnaire (UAB-Q) score, and urodynamic evaluation. Results and limitations: The difference in improvement in PVR was −157.8 ml (95% confidence interval [CI]: −380.1, 64.4) versus −6.6 ml (95% CI: −178.1, 164.9) and −77.5 ml (95% CI: −242.1, 87.1) versus 81.8 ml (95% CI: −137.2, 300.7) for ESWT versus placebo (p = 0.116 and 0.056) at 4 and 12 wk, respectively. The ESWT group exhibited a significant reduction in the UAB-Q score (−4.3; 95% CI: −9.1, 0.4) compared with the placebo group (−0.4; 95% CI: −1.8, 1.0) at 4 wk after treatment (p = 0.025), and the effects were decreased at 12 wk (p = 0.091). This study was limited by small sample size. Conclusions: ESWT was well tolerated with a statistically significant decrease of DU/UAB symptoms and a trend to decrease PVR versus placebo. These results indicate that ESWT may be a promising treatment for DU/UAB and multicenter studies are needed. Patient summary: Bladder shock wave therapy was studied in this randomized, double-blind, placebo-controlled study in patients with inadequate bladder emptying (underactive bladder). Bladder shock wave therapy was found to be well tolerated with an improvement in bladder emptying. These results indicate that bladder shock wave therapy may be a promising treatment for patients who cannot empty their bladder adequately.