The National Institute for Clinical Excellence is examining sacral nerve stimulation for urge incontinence and urgency-frequency and will publish guidance on its safety and efficacy to the NHS in England, Wales and Scotland. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisors, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about sacral nerve stimulation for urge incontinence and urgency-frequency.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the preliminary recommendation
• the identification of factual inaccuracies
• additional relevant evidence.

Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that the Institute will follow after the consultation period ends is as follows.

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for the Institute's guidance on the use of the procedure in the NHS in England, Wales and Scotland.

For further details, see the Interim Guide to the Interventional Procedures Programme, which is available from the Institute's website (www.nice.org.uk/ip).

Closing date for comments: 23 March 2004

Target date for publication of guidance: June 2004

Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.

Current evidence on the safety and efficacy of sacral nerve stimulation for urge incontinence and urgency-frequency appears adequate to support the use of this procedure provided that the normal arrangements are in place for consent, audit and clinical governance.

Patient selection is important. The diagnosis should be defined as clearly as possible and the procedure limited to patients who have not responded to conservative treatments such as lifestyle modifications, behavioural techniques and drug therapy. Patients should be selected on the basis of their response to peripheral nerve evaluation.

Sacral nerve stimulation is used to treat the symptoms of overactive bladder, including urinary urge incontinence and urgency-frequency, alone or in combination, in patients who have failed or cannot tolerate conventional treatments.

In patients for whom conservative treatments have been unsuccessful, the standard alternatives include bladder reconstruction (such as augmentation and cystoplasty) and urinary diversion.

Sacral nerve stimulation involves applying an electric current to one of the sacral nerves via an electrode placed through the corresponding sacral foramen. The electrode leads are attached to an implantable pulse generator, which stimulates the efferent nervous system of the lower urinary tract.

This procedure was subject to a systematic review commissioned by the Institute in November 2003. Evidence from two randomised controlled trials (RCTs) on patients with urge incontinence showed that complete continence (completely dry with no incontinent episodes) or improvement of more than 50% in incontinence symptoms, was observed in 50% and 80% of patients, respectively, following the procedure. This compared with 5% of patients in the control groups, who were receiving conservative treatments while waiting for an implant. In the one RCT reporting on patients with urgency-frequency, an improvement of more than 50% in incontinence symptoms was observed in 56% of patients, compared with 4% in the control group. For more details, refer to the Sources of evidence (see Appendix).

The results of the case series studies included in the systematic review showed similar results, with complete continence and improvement in symptoms being reported in 39% (139/361) and 67% (338/501), respectively, of patients with urge incontinence, and 41% (22/54) and 65% (75/116) of patients with urgency-frequency. The benefits of sacral nerve stimulation were reported to persist for 3-5 years after implantation. For more details, refer to the Sources of evidence (see Appendix).

The Specialist Advisors reported that 50-70% of implants were successful, although a significant proportion of these (about 30%) required surgical revision after a few years. Longer-term success rates (after more than 10 years) were unknown.

In general, evidence on the safety of this procedure was not well reported. Most complications observed in the studies were the result of technical problems related to implantation of the device. The results of the systematic review showed that, overall, the re-operation rate for implanted patients was 33%. The most common reasons for surgical revision were to replace or reposition implants due to pain or infection at the implant site, or to adjust and modify the lead system to correct breakage or migration. For more details, refer to the Sources of evidence (see Appendix).

Pain at the site of the pulse generator or at the site of stimulation was reported in 24% of patients (162/663), although replacement and repositioning of the pulse generator may resolve this. Other complications included lead migration (16%); wound problems (7%); adverse effects on bowel function (6%) and infection (5%). No cases of long-lasting neurological complication were identified. For more details, refer to the Sources of evidence (see Appendix).

The Specialist Advisors were divided in their views about the safety of this procedure; some believed that the risk of patient harm was probably very low, while others cited a range of common complications and adverse events, similar to those above.

There is a lack of long-term quality of life data.

There is limited evidence relating to the use of this procedure in older patients.

More evidence is available for patients with urge incontinence than for urgency-frequency.

The following documents, which summarise the evidence, were considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.

• Interventional procedure overview of sacral nerve stimulation for urge incontinence, October 2002

Available from: www.nice.org.uk/ip082overview

• Systematic review of the efficacy and safety of sacral nerve stimulation for urinary urge incontinence and urgency-frequency, commissioned by NICE and produced by the Health Services Research Unit in November 2003.

Available from: www.nice.org.uk/ip082systematicreview