WITHDRAWN: Transcutaneous electrical stimulation (TES) for treatment of constipation in children

Childhood constipation is a common problem with substantial health, economic and emotional burdens. Existing therapeutic options, mainly pharmacological, are not consistently effective, and some are associated with adverse effects after prolonged use. Transcutaneous electrical stimulation (TES), a non-pharmacological approach, is postulated to facilitate bowel movement by modulating the nerves of the large bowel via the application of electrical current transmitted through the abdominal wall.

Our main objective was to evaluate the effectiveness and safety of TES when employed to improve bowel function and constipation-related symptoms in children with constipation.

We searched MEDLINE (PubMed) (1950 to July 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 7, 2015), EMBASE (1980 to July 2015), the Cochrane IBD Group Specialized Register, trial registries and conference proceedings to identify applicable studies .

Randomized controlled trials that assessed any type of TES, administered at home or in a clinical setting, compared to no treatment, a sham TES, other forms of nerve stimulation or any other pharmaceutical or non-pharmaceutical measures used to treat constipation in children were considered for inclusion.

Two authors independently assessed studies for inclusion, extracted data and assessed risk of bias of the included studies. We calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for categorical outcomes data and the mean difference (MD) and corresponding 95% CI for continuous outcomes.

One study from Australia including 46 children aged 8 to 18 years was eligible for inclusion. There were multiple reports identified, including one unpublished report, that focused on different outcomes of the same study. The study had unclear risk of selection bias, high risks of performance, detection and attrition biases, and low risks of reporting biases.There were no significant differences between TES and the sham control group for the following outcomes: i).number of children with > 3 complete spontaneous bowel movements (CSBM) per week (RR 1.07, 95% CI 0.74 to 1.53, one study, 42 participants) (Quality of evidence: very low, due to high risk of bias and serious imprecision ), ii). number of children with improved colonic transit assessed radiologically (RR 5.00, 95% CI 0.79 to 31.63; one study, 21 participants) (Quality of evidence: very low, due to high risk of bias, serious imprecision and indirectness of the outcome). However, mean colonic transit rate, measured as the position of the geometric centre of the radioactive substance ingested along the intestinal tract, was significantly higher in children who received TES compared to sham (MD 1.05, 95% CI 0.36 to 1.74; one study, 30 participants) (Quality of evidence: very low, due to high risk of bias , serious imprecision and indirectness of the outcome). There was no significant difference between the two groups in the number of children with improved soiling-related symptoms (RR 2.08, 95% CI 0.86 to 5.00; one study, 25 participants) (Quality of evidence: very low, due to high risk of bias and serious imprecision). There was no significant difference in the number of children with improved quality of life (QoL) (RR 4.00, 95% CI 0.56 to 28.40; one study, 16 participants) (Quality of evidence: very low, due to high risk of bias issues and serious imprecision ). There were also no significant differences in in self-perceived (MD 5.00, 95% CI -1.21 to 11.21) or parent-perceived QoL (MD -0.20, 95% CI -7.57 to 7.17, one study, 33 participants for both outcomes) (Quality of evidence for both outcomes: very low, due to high risk of bias and serious imprecision). No adverse effects were reported in the included study.

The results for the outcomes assessed in this review are uncertain. Thus no firm conclusions regarding the efficacy and safety of TES in children with chronic constipation can be drawn. Further randomized controlled trials assessing TES for the management of childhood constipation should be conducted. Future trials should include clear documentation of methodologies, especially measures to evaluate the effectiveness of blinding, and incorporate patient-important outcomes such as the number of patients with improved CSBM, improved clinical symptoms and quality of life.