Understanding Mechanisms of Normal and Disordered Defecation

September 26, 2023 updated by: Adil Bharucha, MBBS, MD, Mayo Clinic
Researchers are trying to better understand why constipation occurs and improve the tests for diagnosing these conditions.

Study Overview

Detailed Description

Study includes a screening visit and a study day. During the initial screening visit for this study, subjects will complete three (3) questionnaires about their bowel symptoms, overall health, and anxiety and depression. A blood sample (about 4 tablespoons) will be drawn to study the relationship between genes and certain bowel habits. Subjects will be asked to provide a single stool sample to look at the bacteria in the stool.

Before the study, subjects will receive 1 to 2 Fleet's enemas to clean the rectum. After receiving the Fleet's enema (administered through a small plastic tube in the rectum), a swab attached to a small rectal catheter will be used to brush the lining of the rectum and obtain a stool specimen. Then, rectal and anal pressures will be measured by placing a small catheter (plastic tube) in the rectum, and withdrawing it slowly. Rectal sensation will be measured by inflating a small balloon in the rectum.

There are 2 procedures (rectal barostat study and fecomanoflowmetry), each of which lasts approximately 90 minutes. During the rectal barostat study, contractions will be recorded with a balloon inserted into the rectum and inflated. After the barostat study is completed, your rectum will be filled with a small amount of paste. Two thin catheters will be inserted into the anus to measure pressures and electrical activity (electromyography or EMG). Then, you will be asked to sit on a commode, contract (squeeze) your anal muscles, blow into a balloon, and expel the paste into the commode.

Study Type

Interventional

Enrollment (Estimated)

160

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Minnesota
      • Rochester, Minnesota, United States, 55905
        • Recruiting
        • Mayo Clinic in Rochester
        • Principal Investigator:
          • Adil E Bharucha, MD
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

16 years to 78 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria

  • Male and female volunteers aged 18-80 years.
  • Able to provide written informed consent before participating in the study.
  • Able to communicate adequately with the investigator and to comply with the requirements for the entire study.
  • Individuals with chronic constipation for 1 year, with 2 or more of the following symptoms for 3 months or longer: <3 bowel motions/week, straining ≥ 25% of time, hard or lumpy stools ≥ 25% of time, anal digitation ≥ 25% of time, incomplete evacuation ≥ 25% of time, feeling of anorectal blockage ≥ 25% of time.
  • Able to provide written informed consent before participating in the study.
  • Able to communicate adequately with the investigator and to comply with the requirements for the entire study.

Exclusion Criteria

  • Clinical evidence of significant cardiovascular, respiratory, renal, hepatic, gastrointestinal, hematological, neurological, psychiatric or other disease that may interfere with the objectives of the study and/or pose safety concerns.
  • Current symptoms of a functional gastrointestinal disorder assessed by questionnaire.
  • Putative risk factors for pelvic floor trauma: i.e. six or more vaginal deliveries, birthweight >4500gms (macrosomia), or known 3rd or 4th degree perineal tear.
  • Medications that are likely to alter gastrointestinal motility: e.g., opiates and anticholinergic medications; a stable dose of thyroxine and low doses of tricyclic agents (e.g., up to amitriptyline (50 mg daily).
  • Active rectal inflammation, cancer; perianal sepsis; history of pelvic radiation, rectosigmoid surgery or inflammatory bowel disease.*
  • Anxiety or depression as assessed by the Hospital Anxiety and Depression Questionnaire.
  • Pregnant women, prisoners and institutionalized individuals.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Healthy Individuals
Sixty healthy individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Contractions will be recorded with a balloon inserted into the rectum and inflated
Rectum will be filled with a small amount of paste.Two thin catheters will be inserted into the anus to measure pressures and electrical activity (electromyography or EMG). Subjects will be asked to sit on a commode, contract (squeeze) your anal muscles, blow into a balloon, and expel the paste into the commode.
Active Comparator: Constipated Individuals
60 constipated individuals (20 men and 40 women) will undergo an anorectal study which comprises of a rectal barostat study followed by fecoflowmetry
Contractions will be recorded with a balloon inserted into the rectum and inflated
Rectum will be filled with a small amount of paste.Two thin catheters will be inserted into the anus to measure pressures and electrical activity (electromyography or EMG). Subjects will be asked to sit on a commode, contract (squeeze) your anal muscles, blow into a balloon, and expel the paste into the commode.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Rectal emptying
Time Frame: Baseline
Measured by fecomanoflowmetry calculating the mean and maximum flow rate in various conditions (mg/sec), defecated volume (mg), flow time (sec) and time to maximum flow (sec). The amount of artificial stool evacuated is expressed in milligrams. The duration is in seconds. These 2 metrics are integrated to measure mg evacuated/second.
Baseline
Rectoanal pressures
Time Frame: Baseline
Measured by anorectal manometry in mmHg
Baseline

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Anal sphincter electromyography (EMG)
Time Frame: Baseline
Units - mV
Baseline
Rectal compliance measured with a barostat
Time Frame: Baseline
Pressure (mmHg) corresponding to half-maximum rectal volume during rectal distention
Baseline
Rectal Capacity measured with a barostat
Time Frame: Baseline
Rectal volume (ml) at maximum distending pressure during rectal distention
Baseline
Rectal contractile response to distention measured with a sinusoidal oscillator
Time Frame: Baseline
Rectal balloon is inflated to a preload volume of 125ml. The balloon is then oscillated around baseline volume by 25mL for 20 min at a frequency of 5 counts per minute (cpm). The mean rectal pressure (cm H2O) will be calculated over the multiple oscillation cycles within the 20 minute distention segment.
Baseline
Rectal sensory threshold for first sensation to defecate using barostat balloon distention
Time Frame: Baseline
The sensory threshold for first sensation to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the first sensation to defecate.
Baseline
Rectal sensory threshold for desire to defecate using barostat balloon distention
Time Frame: Baseline
The sensory threshold for desire to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the desire to defecate.
Baseline
Rectal sensory threshold for maximum urgency during barostat balloon distention
Time Frame: Baseline
The sensory threshold for maximum urgency to defecate is measured by stepwise inflation of the balloon (0-44 mm Hg, at 4 mm Hg increments). During this assessment participants are asked to report when they have the maximum urgency to defecate.
Baseline
Rectal balloon expulsion time
Time Frame: Baseline
During this test, the time (seconds) required to expel a water-filled rectal balloon (50 ml) will be compared between healthy people and patients
Baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Principal Investigator: Adil E Bharucha, MD, Mayo Clinic

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 29, 2019

Primary Completion (Estimated)

June 1, 2024

Study Completion (Estimated)

June 1, 2024

Study Registration Dates

First Submitted

January 10, 2019

First Submitted That Met QC Criteria

February 13, 2019

First Posted (Actual)

February 15, 2019

Study Record Updates

Last Update Posted (Actual)

September 28, 2023

Last Update Submitted That Met QC Criteria

September 26, 2023

Last Verified

September 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 18-010327
  • R01DK078924 (U.S. NIH Grant/Contract)

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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