LCD L39543: Sacral Nerve Stimulation for the Treatment of Urinary and Fecal Incontinence

Urinary incontinence refers to the involuntary loss of urine.

The overall prevalence of overactive bladder (OAB) in the total United States (U.S.) population was 23.3%, with women reporting OAB almost twice as frequently as men (30.0% vs. 16.4%, respectively). 19 Nearly half of nursing home residents have some degree of incontinence. For noninstitutionalized persons older than 60 years of age, prevalence ranges from 15-35%, with women having twice the prevalence of men. 17

Sacral nerve stimulation (SNS) delivers nonpainful, electrical pulses to the sacral nerves to modulate reflexes that influence the bladder, sphincter, and pelvic floor to improve or restore function. 4 SNS has been approved for use in treating urinary incontinence in the U.S. since 1997. 2

In 2011, SNS was U.S. Food and Drug Administration (FDA) approved for the indication of fecal incontinence (FI). 4 The chronic involuntary loss of stool is a life altering circumstance. In the older population, this represents 1 of the single most frequent precipitating factors for entrance into a nursing home. 2 FI is a common symptom, with a prevalence that ranges from 7-15% in community dwelling men and women, but it is often underreported, as providers seldom screen for FI and patients do not volunteer the symptom, even though the symptoms can have a devastating impact on quality of life (QOL).The strongest independent risk factors for FI in the community are bowel disturbances, especially diarrhea, the symptom of rectal urgency, and burden of chronic illness. 3

Sacral neuromodulation (SNM) is a guideline recommended treatment for voiding dysfunction including urgency, urge incontinence, and nonobstructive retention as well as FI.

SNS is covered for the treatment of urinary urge incontinence, urgency-frequency syndrome, and urinary retention by the Centers for Medicare and Medicaid Services (CMS) National Coverage Determination (NCD) §230.18 Sacral Nerve Stimulation for Urinary Incontinence . Direct stimulation of the sacral nerve(s) via an electrode array implanted at the level of the sacrum is the only treatment modality covered by the NCD. 1

Covered Indications

Urinary Incontinence

SNS is covered for the treatment of urinary urge incontinence, urgency-frequency syndrome, and nonobstructive urinary retention. SNS involves both a temporary test stimulation to determine if an implantable stimulator would be effective and a permanent implantation in appropriate candidates. Both the test and the permanent implantation are covered. 1

Limitations

NCD §230.18 Sacral Nerve Stimulation for Urinary Incontinence describes the following limitations for coverage to apply to all 3 indications:

• Patient must be refractory to conventional therapy (documented behavioral (such as bladder training, or pelvic muscle exercise training), pharmacologic and /or surgical corrective therapy) and be an appropriate surgical candidate such that implantation with anesthesia can occur.

• Patients with stress incontinence, urinary obstruction, and specific neurologic disease (e.g., diabetes with peripheral nerve involvement, multiple sclerosis, spinal cord injury) which are associated with secondary manifestations of the above 3 indications are excluded.

• Patient must have had a successful test stimulation in order to support subsequent implantation. Before a patient is eligible for permanent implantation, he/she must demonstrate a 50% or greater improvement through test stimulation. Improvement is measured through voiding diaries.

• Patient must be able to demonstrate adequate ability to record voiding diary data such that clinical results of the implant procedure can be properly evaluated. 1

Covered Indications /Limitations

Fecal Incontinence (FI)

This A/B Medicare Administrative Contractor (MAC) will cover SNS for FI, when all of the following criteria are met:

• Chronic FI with greater than 2 incontinent episodes on average per week and duration of incontinence greater than 6 months or for more than 12 months after vaginal childbirth; AND

• Documented failure or intolerance to conventional therapy (e.g., dietary modification, the addition of bulking and pharmacologic treatment); AND

• A successful percutaneous test stimulation, defined as at least 50% sustained (more than 48 hours) improvement in symptoms; AND

• Condition is not related to anorectal malformation (e.g., congenital malformation, defects of the external anal sphincter over 60 degrees, visible sequelae of pelvic radiation, active anal abscesses and fistulae) and /or chronic inflammatory bowel disease; AND

• Incontinence is not related to another neurologic condition such as peripheral neuropathy or complete spinal cord injury.

SNS is considered experimental, investigational for the treatment of chronic constipation or chronic pelvic pain (CPP).

Wexner, et al. 2 conducted a multicentered prospective trial to determine the safety and efficacy of SNS in a large population under the rigors of FDA approved investigational protocol. Patients showing ≥50% improvement during test stimulation received chronic implantation of the InterStim TM Therapy (Medtronic; Minneapolis MN). The primary efficacy objective was to demonstrate that ≥50% of subjects would achieve therapeutic success, defined as ≥50% reduction of incontinent episodes per week at 12 months compared with baseline. At 12 months, 83% of subjects achieved therapeutic success (95% confidence interval: 74%-90%; P TM Therapy. They concluded that SNS using InterStim TM Therapy is a safe and effective treatment for patients with FI.

Noblett, et al. 4 reviewed the history, mechanism of action, evolution, and landmark literature for this treatment modality. They concluded that the treatment of neuromodulation for the treatment of refractory voiding and bowel dysfunction has provided an effective alternative therapy for patients who have failed more conservative treatments. Data supports the long-term efficacy and safety of SNS for the treatment of bladder and bowel dysfunction.

Siegel, et al. 7 conducted a multicenter clinical trial to measure the effectiveness of SNS in 10 patients with chronic intractable pelvic pain. They performed a prospective nonrandomized study to characterize the safety and efficacy of SNS for chronic intractable pelvic and /or urogenital pain in 10 patients with a history of pelvic pain that persisted for at least 6 months and was refractory to conventional treatment. Due to their small sample size they did not anticipate that the data from this study would be suitable for statistical analysis. They concluded that the data in their feasibility study implied that transforaminal SNS decreases the severity, number of hours, and rate of pain in patients with chronic intractable pelvic pain. From a clinical viewpoint, 6 of 10 patients reported substantial benefit from treatment. A multicenter, statistically powered study should be performed to evaluate the validity of these trends.

Paquette, et al. 8 conducted an organized search of Medline, PubMed, Embase, and the Cochrane Database of Collected Reviews. The scope of this updated practice parameter was to address the evaluation and management of patients with FI based on a thorough review of the published literature. SNM is thought to modulate rectal sensation by activating or deactivating chemical mediating receptors, stimulating the afferent pathway, and changing brain activity relevant to the continence mechanism. SNM has been consistently shown to result in a reduction in frequency of FI episodes. Pooled analysis of all studies to date indicates that 79% (69-83%) of patients experience ≥50% improvements in weekly FI episodes in the short term (0-12 months) and 84% of patients experience ≥50% improvement at long-term (>36 month) follow-up when a per protocol analysis is followed (only patients who received a full system implant are analyzed). SNM may be considered as a first line surgical option for incontinent patients. Grade of Recommendation: Strong recommendation based on moderate quality evidence, 1B.