Colonic Motility in Constipation and Ageing
Condition: Ageing; Constipation
MeSH terms: Constipation
Study type: Observational

Summary: 
      The reason chronic constipation (CC) becomes commoner with age is not fully understood. New
      studies suggest that bowel contraction patterns, dietary fibre and gut bacteria are important
      and may differ in older people. Since CC reduces quality of life and is a major reason why
      elderly are admitted to hospitals and residential care, there is a need to understand how
      these factors change with age.

      Currently, placing a pressure sensing catheter inside the large intestine (pancolonic
      manometry) is the gold standard way to measure how well it contracts. However this involves a
      camera test (colonoscopy) which is invasive with risks of bowel perforations (~80/100,000).
      The risk is higher with age (64-80yr: ~90/100,000; 80+yrs: ~120/100,000), making it unethical
      for elderly.

      A technique called the 3D-Transit System has been developed, involving a small ingestible
      capsule, containing a 'trackable' electromagnet. By tracking movements of the capsule
      swallowed by participants, it provides precise detailed information on the capsule
      progression inside the whole gut and large bowel's contractile activity in real-time. It is
      minimally-invasive and radiation-free, making it possible to assess elderly for the first
      time.

      This study aims to assess how bowel contraction patterns, dietary fibre intake and gut
      bacteria differ between young and older adults (with and without CC), to better understand
      why CC is more common in elderly.

      It is a pilot, 4 arm, single centre, observational study involving 60 women aged 18-40 years
      and 70-90 years (15 non-constipated and 15 with CC for each age group). The study lasts 3
      weeks, containing 2 weeks of run-in period and 1 week of study period.

      The four groups participants will be asked to: swallow 2 capsules to assess their large
      bowel's contractile function using the 3D-transit system; provide stool samples to analyses
      their gut bacteria; and complete questionnaires to assess their gastrointestinal symptoms.
    

Detailed description: 
      Type of study Experimental study comparing colonic contractile functions (including
      region-specific gut transit times) between healthy young vs. older women, and between
      constipated young women vs. constipated older women

      Design 4-arm observational pilot study

      Study Population The study will include 15 healthy young women, 15 healthy older women, 15
      young women with chronic constipation and 15 older women with chronic constipation (but
      otherwise healthy). Vulnerable subject groups (e.g. elderly with dementia) will not be
      included.

      Subject Recruitment Participants with constipation will be identified mainly from the
      existing database of patients with constipation who had previously participated in research
      or undertaken anorectal physiology investigations at the GI physiology unit (part of Queen
      Mary University of London). [The GI physiology unit is part of an academic institution (Queen
      Mary University of London) and not part of the NHS. However being a specialised centre for
      anorectal physiological assessments, it investigates patients referred from various NHS sites
      throughout the UK. Thus it has built up a database of individuals with constipation who had
      previously undergone anorectal examinations and/or research]. Suitable participants will be
      identified by the Director (also Chief Investigator for this study) and staff of the GI
      physiology unit, who have access to the database and patients' medical records and personal
      data. Following identification, an invitation letter (containing the research team's contact
      details) will be sent to patients by the director of the unit (see supporting document).
      Potential participants with constipation will also be recruited via advertisement.

      Participants without constipation will be recruited using mailing lists of public involvement
      groups. Participants will also be recruited through advertisements, posters, and/or websites
      in local media, social media, websites, academic institution, medical institutions and GP
      surgeries. The same text and layout will be used for all forms of advertising.

      Participants who contact us to express interest will be asked to provide us their contact
      details so that we can send them details of the study including the participant information
      sheet.

      Participants will be asked to read this information sheet and to contact us if they require
      any clarification or further explanations. Participant will be asked to take as long as they
      wish to consider the information given and if they wish, to discuss with any family, friends,
      GP or INVOLVE [(http://www.invo.org.uk/) a national advisory group that supports greater
      public involvement in NHS, public health and social care research, who share knowledge and
      learning on public involvement in research]

      Participants who would like to participate after reading the study information sheet will be
      asked to contact us again to arrange a date for a pre-screening telephone call.

      For participants who met the criteria during pre-screening, a date for the screening visit
      will be arranged where full screening will take place.

      After the study is explained in detail to the subjects at the study site during the screening
      visit (V1, see below), and they have agreed to participate by signing the written informed
      consent form, an eligibility checklist will be completed.

      Volunteers will be compensated for their participation in the study and travel expenses will
      be reimbursed.

      Study visits Initial pre-screening (by telephone) On the agreed day, a qualified member of
      the research team will make a phone call to individuals who are interested in participating
      in the study after reading the participant information sheet. Verbal consent will be obtained
      and potential participants will be pre-screened against the main inclusion and exclusion
      criteria.

      Screening V1 (study day -14)

      At V1, a full screening will be performed in person to evaluate eligibility according to the
      criteria. Assessments will include evaluation of:

        -  Medical and surgical history

        -  Symptoms of constipation, using a screening questionnaire detailing American College of
           Gastroenterology definition of constipation, the CCCS questionnaire and Bristol Stool
           Scale. (Subjects will be asked to complete other questionnaires such as PAC-SYM and HADS
           at the baseline visit - see below).

        -  Concomitant diseases

        -  Current medications, particularly treatments used for symptoms of constipation within
           the past 12 weeks

        -  Barthel index (See supporting document)

        -  Pregnancy status of the women subjects with child-bearing potential, using urinary
           pregnancy tests. Appropriate advice will be given to all women of potential
           child-bearing age stating that they must be willing to use a 'highly effective' method
           of contraception (hormonal or barrier method of birth control; abstinence) from the time
           consent is signed until completion of the study.

        -  Abdominal diameter, measured as the circumference at the level of the umbilicus

      For eligible subjects:

        -  Written informed consent & participant demographic data will be obtained

        -  Subjects will be instructed to start a 2 week run in period, during which they will
           continue with their usual diet, physical activity but will discontinue use of laxative,
           prokinetics, probiotics, prebiotics, or fibre supplements until the end of the study.

        -  Subjects will be instructed to read food labels carefully to check the content for
           addition of probiotics or prebiotics. Subjects are permitted to use Bisacodyl or
           glycerine suppositories as rescue laxatives if they had not had a bowel movement for 4
           or more days and experienced abdominal discomfort; its use needs to be documented on the
           stool diaries.

        -  Baseline visit will be scheduled. To eliminate the potential effect of hormonal changes
           on bowel function, baseline date will be synchronized to the menstrual cycle for
           premenopausal women (subjects to start in the midfollicular phase [days 6 - 8 of the
           menstrual cycle].

        -  Subjects will be asked to collect a single fresh stool sample and bring it to the study
           centre either on the baseline visit day or anytime during the 5 days prior to the
           baseline visit, provided that the sample is transferred to the study centre within 3
           hours of collection. Stool samples collected during the study will be initially handled
           at Queen Mary University of London. Samples will be sent from the chief investigator (Dr
           Mark Scott, Wingate Institute, 26 Ashfield Street, E1 2AJ, Queen Mary University of
           London) to King's College London (Professor Kevin Whelan, Diabetes and Nutritional
           Sciences Division, 150 Stamford Street, SE1 9NH), and Nestle Research Centre (Dr Peter
           Duncan, PO Box 44, CH-1000, Lausanne 26, Switzerland) for further stool microbiology
           analysis. All experimental material will be destroyed at the end of the study.

        -  Subjects will be asked to complete a daily bowel diary for 1 week and a food diary for 3
           days (Sat, Mon, Tue) before baseline visit.

             -  For elderly participants who have difficulties attending the study centre, study
                staff will perform the subsequent visits at the participants' home (following
                consent). This will be considered on an individual basis.

      Baseline V2 (study day 0) On the day of the experiment (study day 0), participants will visit
      the study centre at 8 am after an overnight fast. The participants will be provided with a
      standardized breakfast snack and the detector will be attached. Capsules (capsule 1 and
      capsule 2) will be activated and communication between the capsules and the detector will be
      confirmed. Immediately afterwards, capsule 1 will be swallowed with a glass of water at 8 am.
      Subjects will then be asked to complete the following questionnaires before leaving the study
      centre: St Mark's Incontinence scale, PAC-QOL, PAC-SYM, SF12 and HADS. Questionnaire entries
      will be reviewed immediately by the investigator upon collection

      Participants will also be asked to keep a second bowel diary and a record of their meal times
      during the study period.

      The participants will be instructed not to eat again for six hours to avoid prolongation of
      gastric emptying. Throughout the study period, participants will be allowed to perform most
      of their normal daily activities, including taking public transportation and going to work.
      Hard physical activities (work and all sports) will be prohibited. They will also be asked to
      wear the detector vest at all times throughout the study. The detector vest will only be
      taken off for a few minutes each morning to allow participants to take a shower.

      All potential adverse events / serious adverse events and changes in concomitant diseases /
      medications since the screening visit will be monitored throughout the study period.

      Study period V3 (study day 1) After an overnight fast, participants will visit the study
      centre at 8 am. Participants will be provided with a standardized breakfast snack and asked
      to swallow the second capsule (capsule 2). The study staff will perform a review of any
      adverse events. The participants will be instructed not to eat again for six hours following
      ingestion of the capsule to avoid prolonging gastric emptying.

      Study period V4 (any between Day 2 and Day 6):

      Participants will be asked to return to the study centre when they have a bowel movement and
      observed that both capsules (1 & 2) have been expulsed from the body with their faeces. If
      participants have not defaecated after 5 days have elapsed following ingestion of the last
      capsule, they will be also asked to return to the study centre.

      During this visit, the study staff will download the data from the detector vest and check if
      any of the capsules remain in the participants' gastrointestinal tract using a laptop and the
      software for the ambulatory 3D-transit system.

      The study's end date is dependent on the retention time of both capsules. The study will
      terminate if:

        1. It has been confirmed that both capsules have exited the body; or

        2. 5 days have elapsed since ingestion of the last capsule (maximum battery life of each
           capsule is 5 days), whichever occurs earlier.

      The detector will be removed when the study is terminated. In non-constipated subjects (who
      defaecate at least 3 times per week as defined by the inclusion / exclusion criteria), the
      study is anticipated to end 3 days after ingestion of the second capsule (at the latest). In
      constipated participants (who defaecate <3 times per week as defined as defined by the
      inclusion / exclusion criteria), the study is anticipated to end 5 days after ingestion of
      the second capsule (at the latest).

      For subjects who still have one or both of the capsules remaining in the gastrointestinal
      tract during V4, the research team will perform telephone follow up to check if participants
      have developed any abdominal symptoms until the participants have a bowel opening and observe
      that both capsules (capsule 1 & 2) have been expulsed from the body.

      Study duration The duration of the study for each subject will be 3 weeks. This is comprised
      of 2 weeks of run-in period (following screening & enrolment) and a maximum of 1 week of
      study period (following capsule ingestion).
    

Intervention name(s): 3D-Transit system
Intervention type(s): Device
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        30 women aged 18-40 years (15 non-constipated women, 15 with chronic constipation) and 30
        women aged between 70-90 years (15 non-constipated women, 15 with chronic constipation)
        will be recruited, via advertisement in the community.