Sensory Adaptation Training or Escitalopram for IBS With Constipation and Rectal Hypersensitivity: A Randomized Controlled Trial

Abstract

Introduction: Rectal hypersensitivity is an important pathophysiological dysfunction in irritable bowel syndrome with predominant constipation (IBS-C), whose treatment remains challenging. In a randomized controlled trial, we compared the efficacy and safety of a novel sensori-behavioral treatment, sensory adaptation training (SAT) with escitalopram.

Methods: Patients with IBS-C (Rome III) with rectal hypersensitivity received 6 biweekly sessions of SAT or escitalopram 10 mg daily for 3 months. SAT was performed by repetitive gradual distension of 10-cm long highly compliant rectal balloon above tolerability thresholds using barostat. Treatment effects on sensory thresholds and symptoms were compared. Coprimary outcome measures were those achieving improvements in rectal hypersensitivity (≥20% increase in ≥2/3 sensory thresholds) and pain (≥30% decrease).

Results: We randomized 49 patients; 26 received SAT and 23 escitalopram. SAT significantly improved desire to defecate (Δ 13.5 ± 2.3 vs 2.2 ± 1.1 mm Hg, P = 0.0006) and maximum tolerability (Δ 14.8 ± 1.9 vs 1.6 ± 0.9 mm Hg, P < 0.0001) thresholds compared with escitalopram. There were significantly greater percentage of hypersensitivity responders with SAT than escitalopram (69% vs 17%, P < 0.001), but not pain responders (58% vs 44%, P = 0.4). Daily pain scores did not differ between groups (P = 0.8) or escitalopram (P = 0.06) but decreased with SAT (P = 0.0046) compared with baseline. SAT significantly increased rectal compliance (P < 0.019) and complete spontaneous bowel movements per week than escitalopram (P = 0.04). Five withdrew from adverse events with escitalopram and none with SAT.

Discussion: SAT was significantly more efficacious in improving hypersensitivity and bowel symptoms in IBS-C than escitalopram. SAT is a promising novel treatment for IBS with rectal hypersensitivity.

Trial registration: ClinicalTrials.gov NCT00584571.

Conflict of interest statement

Guarantor of the article: Satish S.C. Rao, MD, PhD, FRCP.

Specific author contributions: S.S.C.R.: principal investigator, study concept and design, grant support, data analysis and interpretation, sensory adaptation training supervision, manuscript preparation, overall supervision, and critical revision. J.V.: study coordinator, sensory adaptation training, and data collection. Y.Y.: data analysis, tables and figures, and statistical analysis. E.C.-A.: study recruitment, coordination, sensory adaptation training, and manuscript preparation. A.E.: study recruitment, coordination, and sensory adaptation training. D.A.: statistical methods, data analysis, and manuscript preparation. All authors have approved the final version of the manuscript submitted.

Financial support: This work was supported by NIH grant R01 DK 57100-05 and grant RR00059 from the General Clinical Research Centers program, National Center for Research Resources to University of Iowa. The study was conducted at Augusta University Medical Center and the University of Iowa Hospitals and Clinics, and data analysis and manuscript writing were completed at Augusta University.

Potential competing interests: None to report.

Trial registration: Registered at ClinicalTrials.gov no NCT00584571.

Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.

Figures

Figure 1.

Consort flow diagram. AE, adverse event; GI, gastrointestinal; MAO, monoamine oxidase; SAT, sensory adaptation training; SSRI, selective serotonin reuptake inhibitor.

Figure 2.

Effects on rectal sensory pressure thresholds. Mean ± SEM. SAT, sensory adaptation training.

Figure 3.

Effects on hypersensitivity, abdominal pain, and overall responders. SAT, sensory adaptation training.