Only one study has evaluated the effect of TENS in LUTD in Parkinson's syndromes. It was reported at the congress of the "Société Interdisciplinaire Francophone d'UroDynamique et de Pelvi-Perinéologie" (SIFUD-PP) in 2011 by Ohanessian et al., and comprised 6 female patients with Parkinson's disease (PD) or multisystem atrophy (MSA), with overactive bladder. Transcutaneous electrical nerve stimulation, 20 minutes daily for 6 weeks, was associated with subjective improvement of LUTD assessed with the Patient Global Impression of Improvement (PGI-I) in 5 of the 6 patients.

In view of the encouraging results of this pilot study, we hypothesize that TENS treatment may improve LUTD in patients with a Parkinson's syndrome, Parkinson's disease (PD) and multisystem atrophy (MSA).

The principal objective is to compare the efficacy of transcutaneous electrical nerve stimulation of the posterior tibial nerve with placebo stimulation, applied 20 minutes daily for 3 months, in Lower Urinary Tract Disorders (LUTD) in patients with Parkinson's disease or multisystem atrophy, evaluated using the PGI-I (Patient Global Impression of improvement) tool.

The secondary objectives are to compare the efficacy of TENS with placebo stimulation on change before/after 3 months of treatment on:

• the intensity of urinary symptoms, evaluated using the Patient Global Impression of Severity (PGI-S) scale
• the number of voidings in 24 hours, number of episodes of urinary incontinence in 24 hours and maximum bladder capacity, evaluated by a voiding diary over 3 days
• urinary symptoms, evaluated with the urinary symptom profile (USP) questionnaire
• quality of life, assessed by the Qualiveen-SF® questionnaire
• post-void residual volume measured by bladder ultrasound and effect on the development of infectious complications, by comparing the number of urinary infections over 3 months in each group.

Lastly, the safety of TENS will be compared with that of placebo stimulation by the occurrence of adverse events during the 3 months of treatment.

Inclusion Criteria:

• Established diagnosis of Parkinson disease or multisystem atrophy
• Refractory lower urinary tract disorders or contra-indications or intolerance to the usual oral treatments
• Patient capable of completing the questionnaires
• Patient whose written informed consent has been obtained
• Patient registered with a social security scheme

Exclusion Criteria:

• Pregnancy and breast-feeding
• Contra-indications to TENS (local skin problems, metal ankle joint replacement, cardiac pacemaker, peripheral neuropathy, subthalamic deep brain stimulation)
• Associated neurological disorders (stroke, dementia, multiple sclerosis, spinal cord lesions, peripheral neuropathy) or urological disorders (bladder outlet obstruction, cancer, pelvic organ prolapse, interstitial cystitis)
• Unilateral neurological disability
• Legally incompetent patient, patient under legal protection
• Participation in another study during the present study