To evaluate percutaneous tibial nerve stimulation (PTNS) effectiveness, durability, and impact on the pathophysiology of overactive bladder syndrome (OAB) in patients who have been previously treated with antimuscarinics without success.

A prospective study that included 200 women diagnosed with OAB between 2007 and 2015 at Virgen de la Victoria University Hospital (Málaga, Spain) was conducted. OAB patients were treated with PTNS therapy after antimuscarinic treatment failed. To evaluate OAB symptoms, clinical and urodynamic studies were performed before and after PTNS treatment. Treatment's success was defined as a reduction of clinical parameters by >50% and an improvement of at least 2 urodynamic parameters by >50%. The Kolmogorov-Smirnov test and Student's t test or Wilcoxon test were used based on the data. A linear correlation analysis and a multivariate linear regression analysis were performed to determine factors associated with the success of PTNS therapy.

Of the patients, 94% experienced a positive response to PTNS considering clinical and urodynamic parameters. PTNS benefits were extended by 24 months. We identified daytime urinary frequency (r = −0.165; P = .024; 95% confidence interval, −0.248 to −0.018) and first sensation of bladder filling (r = 0.208; P = .030; 95% confidence interval, 0.001-0.028) as significant independent predictor factors for PTNS success.

The current data confirmed a high effectiveness of PTNS improving OAB symptoms through 24 months. Furthermore, daytime urinary frequency and first sensation of bladder filling act as a significant independent predictor factors for PTNS success.