Several treatment options are available for stress urinary incontinence (SUI), including
pelvic floor muscle training (PFMT), drug therapy and surgery. Problems exist such
as adherence to PFMT regimens, side effects linked to drug therapy and the risks associated
with surgery. We have evaluated an alternative treatment, electrical stimulation (ES)
with non‐implanted devices, which aims to improve pelvic floor muscle function to
reduce involuntary urine loss. To assess the effects of electrical stimulation with
non‐implanted devices, alone or in combination with other treatment, for managing
stress urinary incontinence or stress‐predominant mixed urinary incontinence in women.
Among the outcomes examined were costs and cost‐effectiveness. We searched the Cochrane
Incontinence Specialised Register, which contains trials identified from the Cochrane
Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE In‐Process, MEDLINE
Epub Ahead of Print, CINAHL, ClinicalTrials.gov, WHO ICTRP and handsearches of journals
and conference proceedings (searched 27 February 2017). We also searched the reference
lists of relevant articles and undertook separate searches to identify studies examining
economic data. We included randomised or quasi‐randomised controlled trials of ES
with non‐implanted devices compared with any other treatment for SUI in women. Eligible
trials included adult women with SUI or stress‐predominant mixed urinary incontinence
(MUI). We excluded studies of women with urgency‐predominant MUI, urgency urinary
incontinence only, or incontinence associated with a neurologic condition. We would
have included economic evaluations had they been conducted alongside eligible trials.
Two review authors independently screened search results, extracted data from eligible
trials and assessed risk of bias, using the Cochrane 'Risk of bias' tool. We would
have performed economic evaluations using the approach recommended by Cochrane Economic
Methods. We identified 56 eligible trials (3781 randomised participants). Eighteen
trials did not report the primary outcomes of subjective cure, improvement of SUI
or incontinence‐specific quality of life (QoL). The risk of bias was generally unclear,
as most trials provided little detail when reporting their methods. We assessed 25%
of the included trials as being at high risk of bias for a variety of reasons, including
industry funding and baseline differences between groups. We did not identify any
economic evaluations. For subjective cure of SUI, we found moderate‐quality evidence
that ES is probably better than no active treatment (risk ratio (RR) 2.31, 95% CI
1.06 to 5.02). We found a similar result for cure or improvement of SUI (RR 1.73,
95% CI 1.41 to 2.11), but the quality of evidence was lower. We are very uncertain
if there is a difference between ES and sham treatment in terms of subjective cure
because of the very low quality of evidence (RR 2.21, 95% CI 0.38 to 12.73). For subjective
cure or improvement, ES may be better than sham treatment (RR 2.03, 95% CI 1.02 to
4.07). The effect estimate was 660/1000 women cured/improved with ES compared to 382/1000
with no active treatment (95% CI 538 to 805 women); and for sham treatment, 402/1000
women cured/improved with ES compared to 198/1000 with sham treatment (95% CI 202
to 805 women). Low‐quality evidence suggests that there may be no difference in cure
or improvement for ES versus PFMT (RR 0.85, 95% CI 0.70 to 1.03), PFMT plus ES versus
PFMT alone (RR 1.10, 95% CI 0.95 to 1.28) or ES versus vaginal cones (RR 1.09, 95%
CI 0.97 to 1.21). Electrical stimulation probably improves incontinence‐specific QoL
compared to no treatment (moderate quality evidence) but there may be little or no
difference between electrical stimulation and PFMT (low quality evidence). It is uncertain
whether adding electrical stimulation to PFMT makes any difference in terms of quality
of life, compared with PFMT alone (very low quality evidence). There may be little
or no difference between electrical stimulation and vaginal cones in improving incontinence‐specific
QoL (low quality evidence). The impact of electrical stimulation on subjective cure/improvement
and incontinence‐specific QoL, compared with vaginal cones, PFMT plus vaginal cones,
or drugs therapy, is uncertain (very low quality evidence). In terms of subjective
cure/improvement and incontinence‐specific QoL, the available evidence comparing ES
versus drug therapy or PFMT plus vaginal cones was very low quality and inconclusive.
Similarly, comparisons of different types of ES to each other and of ES plus surgery
to surgery are also inconclusive in terms of subjective cure/improvement and incontinence‐specific
QoL (very low‐quality evidence). Adverse effects were rare: in total nine of the women
treated with ES in the trials reported an adverse effect. We identified insufficient
evidence to compare the risk of adverse effects in women treated with ES compared
to any other treatment. We were unable to identify any economic data. The current
evidence base indicated that electrical stimulation is probably more effective than
no active or sham treatment, but it is not possible to say whether ES is similar to
PFMT or other active treatments in effectiveness or not. Overall, the quality of the
evidence was too low to provide reliable results. Without sufficiently powered trials
measuring clinically important outcomes, such as subjective assessment of urinary
incontinence, we cannot draw robust conclusions about the overall effectiveness or
cost‐effectiveness of electrical stimulation for stress urinary incontinence in women.
Review question We investigated whether electrical stimulation was better than no
treatment at all or better than other available treatments for curing or improving
stress urinary incontinence (SUI) symptoms in women. We also investigated whether
SUI was cured or improved by adding electrical stimulation to other treatments, compared
to other treatments and to different types of electrical stimulation. Finally, we
investigated whether electrical stimulation represented value for money. Background
About 25% to 45% of women worldwide have problems with leaking urine involuntarily.
Women with SUI often leak urine with physical exertion such as coughing or sneezing.
SUI can be treated with pelvic floor muscle exercises, vaginal cones, drug therapy
or surgery, but there are various problems with these treatments. A possible alternative
is electrical stimulation with non‐implanted devices, whereby an electrical current
is delivered through vaginal electrodes. How up‐to‐date is this review? We searched
for studies that had been published up to 27 February 2017. Study characteristics
We found 56 trials (involving a total of 3781 women, all with stress urinary incontinence
but some with urgency urinary incontinence as well) comparing electrical stimulation
to no treatment or to any other available treatment. Key results For cure or improvement
of SUI, electrical stimulation was probably better than no active or sham treatment.
There was not enough evidence to say whether it was any better than pelvic floor muscle
training for curing or improving SUI, or for quality of life. Adding electrical stimulation
to pelvic floor muscle training may not make much difference to cure or improvement
of SUI. It is uncertain whether it offers any improvement in quality of life compared
with pelvic floor muscle training. We found that few women reported adverse effects
with electrical stimulation, but there was not enough reliable evidence comparing
electrical stimulation to other treatments to know more about its safety. There was
not enough evidence comparing electrical stimulation to other existing treatments
such as drug therapy, pelvic floor muscle training plus vaginal cones, surgery, or
different forms of electrical stimulation, to provide evidence‐based guidance on which
would be better, and for which women, in curing or improving SUI or in improving quality
of life. There was no information from these studies to judge value for money. Quality
of the evidence There is some evidence to support the use of electrical stimulation
for stress urinary incontinence in women, but we are still very uncertain about the
full potential of this treatment because of the low quality of the existing evidence.
While we found evidence indicating that electrical stimulation may be better than
no treatment, we did not find enough well‐designed trials with enough women to fully
answer our review questions, so we do not yet know if ES is better or worse than other
treatments.