Transabdominal interferential therapy effective against constipation in women

Transabdominal interferential electrical stimulation induces bowel symptom improvements in chronically constipated women, and the effects may be sustained 3 months after therapy, according to the results of a trial.

The nonpharmacological intervention is well-tolerated and effectively reduces symptom severity, increases spontaneous defecation and cuts laxative use, the investigators said, adding that it is a promising addition in the treatment toolbox for patients with refractory constipation symptoms.

Thirty-three women (average age, 45 years) with refractory constipation were randomized to undergo interferential stimulation (with crossing of electric currents [IFT]; n=17) or a novel sham stimulation (no crossing of currents; n=16) for 1 hour a day for 6 weeks.

Significantly more patients in the IFT than in the sham group achieved the primary outcome of ≥3 spontaneous bowel movements/week (53 percent vs 12 percent; p=0.02). IFT also yielded greater improvements in symptom severity (assessed using Patient Assessment of Constipation‐Symptoms; p=0.03) and overall symptom scores (p=0.05), while reducing laxative use in 66 percent of patients (vs 14 percent in sham; p=0.01). [Aliment Pharmacol Ther 2020;51:760-769]

All improvements with IFT were maintained at 3 months after cessation of therapy. The two treatment interventions were well tolerated in general. There were no reports of treatment-related adverse events.

“[IFT] is administered via transabdominal electrical stimulation, where the currents pass diagonally from two electrodes over the back lateral to the spine, and two over the abdomen at the level of the umbilicus on the mid clavicular line. This treatment is noninvasive, painless and economical,” the investigators said.

“The mechanism of action of interferential stimulation is still unclear, but hypothesized to have a neuroplastic effect as the onset of action is slow, and paediatric studies have found it continues to have benefit long after cessation of use,” they continued. [Pediatr Surg Int 2015;31:445‐451]

Interferential current stimulation may increase propagating sequences and colonic activity, possibly mediated by effects exerted on the excitability of cells such as those responsible for producing the slow wave activity in the bowel. Alternatively, the current may directly affect the autonomic nervous system either via the afferent or efferent pathways, given that the electrodes are close to the spinal cord. [J Neurogastroenterol Motil 2018;24:19‐29]

The current study has several strengths, including the use of multiple methods of objectively assessing symptoms associated with constipation, treatment being home based, and allowing laxative use on an as‐required basis. On the other hand, it is limited by the small sample size and the unblinded delivery of treatment.

Additional work is required to establish optimal delivery duration and frequency, define mechanisms of action, and determine predictors of response, the investigators said.