Validation of a sham for percutaneous tibial nerve stimulation (PTNS).
ABSTRACT Percutaneous tibial nerve stimulation (PTNS) supposedly demonstrates 50-60% improvement in OAB symptoms with no sham-controlled trials reported. This study determined the efficacy of a sham for PTNS.
Thirty healthy volunteers (15 women; 15 men) in this blinded pilot study were randomized into two equal groups: one group had PTNS on the right and sham on the left; the other group had PTNS on the left and sham on the right. A drape obscured their lower extremities. The sham utilized a placebo needle placed at the PTNS site along with a transcutaneous electrical nerve stimulator (TENS) pad on the ipsilateral foot. The unit was activated until stimulation was felt. PTNS was performed on the opposite leg, with the grounding pad mimicking the sham pad placement. PTNS stimulation was given until the subject felt stimulation in the foot. Subjects had 1 simultaneous 15 min testing of the PTNS vs. sham. Subjects then completed a questionnaire stating which leg they thought had the sham and PTNS (or "unknown"). The primary endpoint of the study was the ability to accurately identify the sham.
In total, 10/30 (33%) of the shams were identified correctly. We would expect 50% to be identified by guessing, but only 33% were correctly identified. Females identified the sham correctly more often than males (40% vs. 27%). This procedure was validated as a feasible sham for PTNS.
This is the first validation of a sham for PTNS that may be used in future placebo-controlled research.
- SourceAvailable from: Jules Schagen van Leeuwen[show abstract] [hide abstract]
ABSTRACT: We reviewed placebo responses in randomised controlled trials (RCTs) for pharmacologic treatment of lower urinary tract symptoms (LUTS), including urinary incontinence (UI), overactive bladder, and benign prostatic hyperplasia. Review papers on placebo effects in non-urologic disorders were assessed to compare the magnitude of placebo responses in drugs for LUTS with those reported for other diseases. Data were retrieved from registration trials for LUTS drugs on the Web sites of the Food and Drugs Administration and the European Medicines Agency. Reviews were retrieved from Medline using the MeSH term "placebo effect" (English language; published between 1990 and 2005). Placebo treatment of LUTS yields reductions in incontinence episodes (IEs) ranging from 32% to 65%, whereas prostate or UI symptom scores are reduced by 9-34%. Genuine drugs decrease IEs by 45-77% and symptom scores by 22-45%. Placebo responses are much lower when objective changes in voided volume or peak flow rate are assessed. The placebo effect in LUTS has a strong behavioural component as patients become aware of their voiding habits and potential risk factors. Symptom severity, treatment naivety, study duration, and interaction with health care providers may also influence it. Proper patient selection, study duration, and objective and subjective outcome measures may better separate genuine treatment effects from artefacts. Observational studies with patients representative for real-life situations and covering a sufficient period of time could allow for better understanding of RCT results and their applicability in clinical practice.European Urology 10/2006; 50(3):440-52; discussion 453. · 10.48 Impact Factor
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ABSTRACT: We reviewed the literature on the application of various devices and techniques for the electrical stimulation treatment of lower urinary tract dysfunction with respect to mechanism of action and clinical outcome. A systematic review was done in PubMed of publications on intravesical stimulation, direct bladder stimulation, stimulation of the pelvic and pudendal nerves, transcutaneous-electrical nerve stimulation, stimulation of the sacral spine and roots, and lower limb stimulation. It is difficult truly to compare different treatment modalities because there are hardly any randomized placebo controlled studies. Also, there is considerable variety in treatment parameters and schedules reported as well as in criteria for success. Nevertheless, it can be said that electrical neurostimulation and neuromodulation result in a 30% to 50% clinical success on an intent to treat basis. Influencing lower urinary tract innervation at the level of sacral roots seems successful in neurological and nonneurological cases. It has the advantage of pretesting possibilities to improve patient selection and treatment outcome with the obvious drawback of invasiveness. Noninvasive techniques lack screening tests, making patient selection a matter of trial and error, and when there is success patients almost always need maintenance therapy. Randomized clinical trials to compare different techniques and evaluate placebo effects are urgently needed, as are further studies to elucidate modes of action to improve stimulation application and therapy results. The introduction of new stimulation methods may provide treatment alternatives as well as help answer more basic questions on electrical neurostimulation and neuromodulation.The Journal of Urology 10/2004; 172(3):846-51. · 3.70 Impact Factor
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ABSTRACT: We treated 14 women with chronic interstitial cystitis with long-term intravaginal or transcutaneous nerve stimulation. Clinical and urodynamic evaluations were done after 6 months to 2 years. Improvement was not immediate but required a considerable period of continuous, daily use of electrical stimulation. The results were favorable--a substantial decrease in pain and frequency of micturition in all patients after long-term treatment. Since the methods seem effective and are simple, cheap and non-destructive electrical stimulation is recommended for all patients with chronic interstitial cystitis.The Journal of Urology 03/1980; 123(2):192-5. · 3.70 Impact Factor