There is a new disease in town
Health providers worldwide are well aware that the treatment of OAB is behavioral modification and antimuscarinic agents with the goal of relieving symptoms and balancing drug treatment efficacy with side effects and costs. Unfortunately for a number of reasons many patients do not reach their treatment goal and suffer from a new disease not yet defined by experts, and in many cases is seldom talked about by patients and health care providers. This disease is called "refractory OAB" and to which I have coined the term "ROAB", a condition that up to now has been hovering below the radar of many caregivers and industry. Well guess what, things are about to change!
Who has ROAB?
Simply stated- millions do! In fact, I believe that ROAB is more prevalent than OAB that is currently effectively managed by medical therapy. Let's face it, more than 50% of patients with OAB do not respond favorably to the medications we prescribe.
ROAB includes those OAB sufferers who:
• Do not respond to antimuscarinics in spite of trying multiple agents
• Cannot tolerate antimuscarinics
• Cannot afford antimuscarinics
• Have contraindications to taking antimuscarinics
• Do not want to take medication
ROAB are those patients who keep coming back and reporting that they are still leaking or voiding frequently and that the expensive medication you prescribed is not helping. In addition, ROAB are those who did not respond to the two weeks of samples given to them by their physician and who simply do not return thinking they cannot be helped and unfortunately surrender to their condition.
How do we treat ROAB?
The good news is that there is now a new treatment for ROAB called Urgent®PC. As of January 1, 2011 Urgent®PC, or percutaneous tibial nerve stimulation (PTNS), is now available and reimbursed as an in-office procedure for patients with refractory OAB. Although Urgent®PC is not a panacea, it does benefit many patients with ROAB giving them hope and dignity.
Neuromodulation for the masses
Although sacral nerve stimulation (Interstim®Medtronic, Inc., Fridley, MN) is an FDA-approved and effective neuromodulation therapy for refractory OAB it simply has not filled the void in treating the millions of patients with ROAB. In spite of its proven effectiveness most urologists do not perform Interstim®, don't refer to those who do, and the procedure may be perceived as too invasive or expensive, especially in the elderly and in those who are frail or have a number of medical co-morbidities. Botulinum toxin (Botox®) injected directly into the detrusor muscle endoscopically is an effective neuromodulation treatment for refractory OAB but its use in clinical practice is currently limited by its lack of FDA-approval.
Though it may appear harsh, beyond the scope of practice of incontinence experts the routine use of neuromodulation as a treatment of lower urinary tract symptoms has not been available to most patients. In contrast, with the advent of Urgent®PC, I predict that the majority of urologists and uro-gynecologists will now begin offering PTNS to patients with OAB. For this reason I have reflected that Urgent®PC is not just launching in-office neuromodulation, it functionally is launching neuromodulation to the masses of physicians and patients who otherwise are not treating or are not being treated for ROAB, respectively.
What is PTNS?
PTNS is a minimally invasive neuromodulation system designed to deliver retrograde electrical stimulation to the sacral nerve plexus through percutaneous electrical stimulation of the posterior tibial nerve. The posterior tibial nerve contains mixed sensory-motor nerve fibers that originate from L4 through S3 which modulate the innervation to the bladder, urinary sphincter and pelvic floor. The specific mechanism of action of neuromodulation is unclear, although theories include improved blood flow or change in neurochemical balance affecting bladder sensory innervation. It has been postulated that neuromodulation may have a direct effect on the detrusor or a central effect on the micturition centers of the brain.
Using a battery powered, hand-held stimulator and a 34 gauge needle electrode, the tibial nerve is accessed and stimulated. Patients receive a 30-minute weekly treatment in the office for twelve weeks. Patients treated with PTNS may begin to see changes in their voiding parameters after 4 - 6 treatments. Treatment responders require additional therapy at individually defined treatment intervals for sustained relief of OAB symptoms.
Clinical effectiveness of PTNS
The data which supports the efficacy of Urgent' pC will be presented. The robustness of the data is supported by:
• the consistency of the efficacy data
• the objective efficacy as measured by urodynamics
• the comparative data to extended-release tolterodine
• the level one evidence demonstrated by the PTNS vs. SHAM study
• the long-term effectiveness of PTNS
Therapeutic algorithm
A therapeutic algorithm from a continence center that for many years has liberally utilized sacral nerve stimulation, PTNS, and botulinum toxin will be presented.
Conclusions
PTNS offers patients with ROAB a minimally invasive, office-based procedure that is safe, effective, and is an important addition to the therapeutic armamentarium. PTNS raises the bar and you simply cannot deliver the same level of efficacy without it. I believe that in-office neuromodulation is here to stay and that one-day we will look back in time and wonder how we ever practiced without it.
Source: SUFU 2011 program book, Original Presentation
