Hypothesis
- To determine the subjective and objective improvement in overactive bladder symptoms following a 12 week course of PTNS therapy.
- To determine the ongoing benefit of the treatment at 4 week follow-up following a 12 week course of PTNS therapy.
MethodThis was a case series of 112 patients who underwent a 12 week course of percutaneous posterior tibial nerve stimulation (PTNS) therapy between August 2012 and July 2014. Patients with irritable bladder symptoms were offered the therapy after failed conservative and medical management. Each patient underwent a 12 week course of PTNS therapy (1x half-hour session per week for 12 weeks). They were asked to complete a validated standardized questionnaire (the OAB-q form) at week 1, week 6, and week 12. They were then followed up in a dedicated clinic 4 weeks after completion of the treatment (i.e. at week 16) where they were asked if they felt that they had benefitted from the treatment (the subjective assessment), and also asked to complete a further OAB-q form for the objetive assesment.
Results
- 112 patients underwent a 12 week course of PTNS therapy between August 2012 and July 2014:
- 57 patients had urodynamically diagnosed Overactive Bladder Syndrome and no other pathology (pure OAB)
- 27 patients had urodynamically diagnosed Overactive Bladder Syndrome and also had stress incontinence (mixed urinary incontinence)
- 14 patients had irritable bladder symptoms but no finding of Overactive Bladder Syndrome on urodynamic investigation (sensory urgency)
- 14 patients had another diagnosis (detrusor sphincter dysynergia n=3; painful bladder syndrome n=3; faecal urgency n=1; neuropathic bladder n=1; voiding dysfunction n=6)
Of those with pure OAB (n=57), 39/57 (68.2%) had a subjectiveimprovementinirritablebladdersymptoms;in those 39 patients who had a subjective improvement, the objective assessment by way of validated questionnaire scores demonstrated a mean improvement of 45.1%. In the patients who subjectively reported no symptom improvement, the validated questionnaire score demonstrated an 18.2% improvement.
Including the patients with mixed urinary incontience in the above figures (n=84), 52/84 (61.9%) had a subjective improvement in overactive bladder symptoms. In those 52 patients who had a subjective improvement, the objective assessment by way of validated questionnaire scores demonstrated a mean improvement of 44.7%. In the patients who subjectively reported no symptom improvement,the validated questionnaire score demonstrated an 18.4% improvement.
In those patients with sensory urgency (n=14), only 3/14(21.4%)reportedasubjectiveimprovementin symptoms. The validated questionnaire score for all these patients (n=14) demonstrated a 9.7% improvement.
Interpretation of resultsPatients with urodynamically diagnosed overactive bladder syndrome appear to have a good chance of significant symptom improvement following treatment with PTNS therapy. Those patients with pure Overactive Bladder Syndrome and no other pathology seem to have the best chance of success (68.2% subjective improvement with corresponding mean 45% improvement in validated questionnaire score).
Patients with overactive bladder symptoms but without a urodynamic diagnosis of overactive bladder syndrome and no other pathology (i.e. sensory urgency) do not appear to have a significant response to PTNS treatment (21.4% subjective improvement with corresponding 9.7% improvement in validated questionnaire score).
The mean validated questionnaire scores for patients undergoing PTNS therapy show a trend of falling during treatment, and then plateau following completion of the treatment at week 12 and review at 4 weeks post-treatment. There is a more marked drop in the mean validated questionnaire scores for those that subjectively report a positive response to the treatment.
Concluding messagePTNS therapy is a viable and effective treatment option in the management of Overactive Bladder Syndrome. Appropriate patient selection for this treatment should include a urodynamic diagnosis of overactive bladder syndrome and the exclusion of other pathology causing irritable bladder symptoms.
Further research would be interesting to determine if ongoing weekly treatment beyond the initial 12 week course leads to further improvements in symptomatology in those patients who have a positive response to treatment.
References
- Burton C et al. Neurourology and Urodynamics. 2012 Nov;31(8):1206-16. Effectiveness of Posterior Tibial Nerve Stimulation for Overactive bladder: a systematic review and meta-analysis.
- Peters KM et al. J Urol. 2010 April;183(4):1438-43. Randomised trial of percutaneous tibial nerve stimulation versus Sham efficacy in the treatment of overactive bladder syndrome: Results from the SUmiT Trial.
- NICE interventional procedures guidance [IPG362]. October 2010. Percutaneous posterior tibial nerve stimulation for overactive bladder syndrome.
