Unilateral and Bilateral Transcutaneous Tibial Nerve Stimulation in Women With Overactive Bladder Syndrome: A Randomized Controlled Study (UBTTNS-OAB Study).

Introduction: The efficacy of unilateral versus bilateral Transcutaneous Tibial Nerve Stimulation (TTNS) for women with Overactive Bladder Syndrome (OAB) remains uncertain.

Objective: To compare the efficacy of unilateral and bilateral TTNS in the tibial region in women with OAB.

Methods: This randomized, controlled, triple-blind clinical trial included women with OAB or urgency-predominant urinary incontinence (UUI). Participants were randomized (1:1) into the Unilateral Tibial Group or Bilateral Tibial Group. Before treatment, they underwent a pre-assessment including peripheral sensitivity examination and completion of sociodemographic data and seven validated questionnaires on urinary symptoms, quality of life, sleep, and psycho-emotional aspects. TTNS interventions were administered twice weekly (12 sessions, 30 min each). Posttreatment, participants underwent another physical examination and completed the same questionnaires, with a 30-day follow-up. Categorical variables were analyzed using Chi-square or Fisher's Exact Test, while numerical variables were assessed with the Mann-Whitney test. Group comparisons over time utilized intention-to-treat ANOVA (p < 0.05).

Results: Thirty-five women participated: 17 in the unilateral group and 18 in the bilateral group. Mean ages were 55.1 (±14.7) years and 52.7 (±12.6) years, respectively (p = 0.680). Initial OAB severity (ICIQ-OAB) did not differ significantly between groups (p = 0.561). Both groups showed significant improvement in ICIQ-OAB scores: unilateral group from 10.1 (±3.4) to 5.8 (±3.4) (p < 0.001), bilateral group from 9.3 (±3.3) to 5.1 (±4) (p < 0.001), with no intergroup difference (p = 0.395). Improvement in UUI symptoms was observed: unilateral group from 2.2 (±1.4) to 0.7 (±1.5), bilateral group from 1.5 (±1.9) to 0.2 (±0.5), without significant intergroup difference (p = 0.645). Quality of life scores improved similarly between groups (p = 0.055).

Conclusion: TTNS appears to be effective in improving bladder storage and UUI symptoms in women with OAB, with no difference between unilateral and bilateral applications.

Clinical Trial Registration: Brazilian Registry of Clinical Trials (REBEC) (RBR: 96f2fgkn).