Clinical Trial to Study a Non-invasive Neurostimulation Device on Urgency (Urinary) Incontinence Overactive Bladder (OAB)

• Change in Mean Daily Urgency Incontinence Episodes [ Time Frame: From baseline to Week 4 of active treatment ] [ Designated as safety issue: No ]
  Mean urgency incontinence episodes (or urinary leaks) over 24 hours is based on a 3-day diary maintained by the subject. Urgency incontinence is when a subject has urinary leakage, i.e., uncontrolled release of fluid prior to making it to the bathroom. The number of leaks over 3 days was recorded for each subject at baseline and again at Week 4. The 3-day average at each time point was used as the mean over 24 hours and the change from baseline to Week 4 was calculated for each subject.
  
  

• Change in Mean Daily Voiding Frequency [ Time Frame: From baseline to Week 4 of active treatment ] [ Designated as safety issue: No ]
  Mean daily voiding frequency over 24 hours is based on a 3-day diary maintained by the subject. Voiding frequency is defined as the number of times a subject urinates. The number of voids over 3 days was recorded for each subject at baseline and again at Week 4. The 3-day average at each time point was used as the mean over 24 hours and the change from baseline to Week 4 was calculated for each subject.
  
  
• Change in Mean Volume Per Void [ Time Frame: From Baseline to Week 4 of active treatment ] [ Designated as safety issue: No ]
  Mean volume per void (or amount of urine per urination) over 24 hours is based on a 3-day diary maintained by the subject. The volume of void (in milliliters) over 3 days was recorded for each subject at baseline and again at Week 4. The 3-day average at each time point was used as the mean over 24 hours and the change from baseline to Week 4 was calculated for each subject.
  
  
• Change in Mean Urgency Episodes Per Day [ Time Frame: From Baseline to Week 4 of active treatment ] [ Designated as safety issue: No ]
  Mean urgency episodes per day is based on a 3-day diary maintained by the subject. An urgency episode is identified by the subject as a case where they have a strong urge to urinate, i.e. difficulty controlling the bladder and thus are rushing to the bathroom. The number of urgency episodes over 3 days was recorded for each subject at baseline and again at Week 4. The 3-day average at each time point was used as the mean over 24 hours and the change from baseline to Week 4 was calculated for each subject.
  
  
• Change in Mean Overactive Bladder Symptom Composite Score [ Time Frame: From Baseline to Week 4 of active treatment ] [ Designated as safety issue: No ]
  The Overactive Bladder Symptom Composite is a composite symptom score of toilet voids, urgency severity and urge urinary incontinence. It combines the Indevus Urgency Severity Scale for capture of urgency severity per toilet void with 24-hour frequency and urinary urge incontinence episodes. A complete reference for this validated measure can be found in teh Journal of Urology, Vol. 173, pgs 1639-1643, May 2005. The scale is specific to the instrument and lower scores represent an improvement in symptoms. The scale is a weighted average of each void a subject has. The weights are assigned as 0=no urgency, 1=mild, 2=moderate, 3=severe. The minimum score is 0, corresponding to no urgency in every void. There is no quantifiable upper limit since the scale is based on the number of voids per day, but there are reasonable upper limits. For example, if a subject had 15 voids in 1 day and all 15 were severe (=3), the Composite Score would be 45. Full details are in the reference above.
  
  

While the precise cause of OAB symptoms (urge, frequency, incontinence) is not clear, most physicians and researchers accept the theory that a problem in the communication between the central nervous system and the bladder is a factor.

Research has shown that a process called neuromodulation of the nerves controlling the bladder can overcome this communication problem. In patients who have symptoms caused by the communication problem, neuromodulation has been clinically proven to eliminate or significantly reduce those symptoms. While neuromodulation has been previously achieved by implanting an electrode near the sacral nerve in the spine, the new concept under investigation within this protocol is believed to achieve a similar effect from adhesive electrodes placed on the skin over spinal nerves in the lower back.