Transcutaneous tibial nerve stimulation (TTNS) is a relatively new treatment route of electrical stimulation for overactive bladder syndrome (OABS) patients. Percutaneous tibial nerve stimulation (PTNS) is supported with good clinical evidence and is recommended in guidelines for OABS patients (1). Robust evidence is still lacking on the efficacy of TTNS for OABS, despite data has been published showing its efficacy compared to PTNS (2). However, clinicians have started to use it widely, due to its non-invasive and easy application features. We aimed to have an insight on the efficacy of TTNS treatment with OABS patients.

We retrospectively analyzed all patients that were treated with TTNS for OABS from June 2018 to March 2022 in our outpatient unit. The diagnosis of OABS was made based on patient complaints and bladder diary results. Patients with non-neurogenic pure urge incontinence and patients with mixed incontinence with predominant urge symptoms were included in the analysis. Patients under the age of 18 were excluded. In a routine scheme, TTNS was given twice weekly for 12 sessions at 6 weeks. TTNS was applied transcutaneously by surface electrodes, with a frequency of 10 Hz for 30 minutes in each session (Biolito, MTR+, Germany). Some patients underwent a weekly maintenance program for 6 weeks depending on  the efficacy of the primary treatment. Patients receiving treatments other than TTNS at the same time were excluded. All patients were also informed about OABS, bladder training and lifestyle modifications and signed informed constent was obtained.
All patients’ age, body mass index (BMI), type of  OABS (wet or dry)  and duration of OABS complaints and general characteristics were evaluated. Three day-bladder diary outcomes, the self-administered questionnaires; the International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF), Overactive Bladder V8 (OAB-V8), patient reported symptom severity of the last 3 days by visual analog scale (VAS: 0-10) and 24 hours pad test results were recorded. All outcome parameters were obtained before and after the treatment in our routine patient follow-up.

Ninety six female patients with OABS were treated with TTNS. Only 72 patients’ data were included in the study analysis. Data of 24 patients’ were excluded as they didn’t have any outcome data for evaluation. Mean patient age was 49.8±12.5, mean BMI was 32.8±6.8, mean number of parity was 2.7±1.7 and 47.2% of the patients were in menapouse. Mean symptom duration for OABS was 50.9±45.9 months and 93.1% patients had wet OABS. 

None of the patients were on any medication for OABS at the time TTNS treatment had initiated. None of the patients had any adverse event during the TTNS procedure. The effectiveness of TTNS treatment was evaluated with 3 day-bladder diary outcomes, 24 hours pad test and questionnaire scores. As a statistical method, we used mean ± SD(standard deviation) in continuous variables and Paired Samples t-Test was performed among dependent groups. (Table 1)

TTNS treatment for OABS in female patients was statistically significantly effective in reducing daytime frequency and incontinence episodes. Statistically significant improvement was observed in ICIQ-SF, OAB-V8 and VAS-symptom severity scores with TTNS treatment. Although improvement was observed, results were not significant in nocturia, nocturnal incontinence, urge incontinence episodes and pad test parameters. 
In general, PTNS is recommended once a week for a total of 12 sessions in OABS patients. We have administered 12 sessions of TTNS with twice weekly sessions for 6 weeks, which was a more intense but a shorter treatment duration. Evidence is lacking about the administration schedule for TTNS. Our impression from clinical experience is that 6 weeks of TTNS is well tolerated and is a preferred method of treatment by patients.

Results from our database showed that TTNS is safe and effective in female patients with OABS. Randomized controlled trials in larger patient populations are needed to prove this efficacy and best treatment regimen for TTNS.

Lightner DJ, Gomelsky A, Souter L et al: Diagnosis and treatment of overactive bladder (non-neurogenic) in adults: AUA/SUFU Guideline amendment 201J Urol 2019; 202: 558.
Ramírez-García I, Blanco-Ratto L, Kauffmann S, Carralero-Martínez A, Sánchez E. Efficacy of transcutaneous stimulation of the posterior tibial nerve compared to percutaneous stimulation in idiopathic overactive bladder syndrome: Randomized control trial. Neurourol Urodyn. 201Jan;38(1):261-26doi: 10.1002/nau.2384Epub 201Oct 1PMID: 30311692.