Randomized Controlled Trial of Treating Rectal Hypersensitivity - Comparing Escitalopram With Sensory Adaptation Training

Constipation is a common digestive disorder. After excluding dietary factors, drugs and other secondary causes, at least three broad pathophysiologic subtypes are recognized- dyssynergic defecation, constipation-predominant irritable bowel syndrome (IBS-C) and slow transit constipation (STC), all predominantly affect women and elderly. Many patients also demonstrate abnormal rectal perception with both rectal hyposensitivity and hypersensitivity being common. Recent surveys show that most constipated patients are dissatisfied with current therapy. Also, constipated patients showed significant psychological dysfunction and impaired quality of life. OBJECTIVE: To investigate a novel biofeedback technique of improving rectal hypersensitivity.

METHODS: A large compliant balloon attached to a barostat was placed in the rectum in 8 patients with rectal hypersensitivity (urgency/pain threshold <30 mm Hg). Sensory deconditioning was performed by incremental balloon distensions (1-2 mmHg) until normal thresholds were reached.

• Rectal Hypersensitivity
• Irritable Bowel Syndrome-Constipation

• Procedure: Sensory Adaptation Training with Barostat
  This study will last for approximately 3 months and will include 4-6 clinic visits with each visit lasting 2 hours every week or every 2 weeks. At the beginning of each visit we will ask you about your health status and level of satisfaction of your bowel habits. We will then place the pencil-thick probe and balloon inside your rectum and attach it to the barostat device and a computer. We will increase and decrease the volumes of the balloon until the most pressure you can tolerate or a certain level of pressure as measured by the machine is reached, whichever occurs first. You will continue to keep stool diaries and pain diaries for 7 days before and after each visit.
  Other Name: Barostat procedure
• Drug: Escitalopram Therapy
  Escitalopram; 10 mg every day, orally.
  Other Name: Lexapro (Escitalopram) therapy

• Active Comparator: Sensory Adaptation
  Intervention: Procedure: Sensory Adaptation Training with Barostat
• Experimental: Escitalopram Therapy
  Intervention: Drug: Escitalopram Therapy

Inclusion Criteria:

All patients must fulfill the diagnostic criteria for IBS-C (Rome III) as defined below and have rectal hypersensitivity (see below).

• Patients must report recurrent abdominal pain or discomfort for at least 3 days per month in the last 3 months with two or more of the following symptoms:

  • Improvement with defecation; and/or
  • Onset associated with a change in frequency of stool; and/or
  • Onset associated with a change in form (appearance) of stool
• No structural diseases

• On a diary:

  • Pain/discomfort for at least 2 days/week;
  • No loose or watery stool <25% of bowel movements.

Exclusion Criteria:

• Patients with mixed-IBS.
• Patients currently on SSRI or MAO inhibitors. Patients on stable doses of other antidepressants will be included provided the dose is unchanged during study.
• Patients taking drugs that are constipating, (e.g.; calcium channel antagonists will either be excluded or drug discontinued)
• Patients with co-morbid illnesses; severe cardiac disease, chronic renal failure or previous gastrointestinal surgery except cholecystectomy and appendectomy.
• Neurologic diseases e.g.; head injury, epilepsy, multiple sclerosis, strokes, spinal cord injuries.
• Impaired cognizance (mini mental score of < 15) and/or legally blind.
• Pregnant or likely to conceive during the course of the study. Women with potential for pregnancy must be willing to use contraceptive measures during the study. Urinary pregnancy tests will be performed on such women prior to any radiologic procedures.
• Hirschsprung's disease.
• Alternating constipation and diarrhea (22).
• Ulcerative/Crohns colitis.
• Previous pelvic surgery, rectocele/bladder repair, radical hysterectomy, anal surgery.
• Rectal prolapse or anal fissure.