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Physical Activity and Gastrointestinal Investigations

An Observational Study to Compare the Outcomes of Ambulatory Gastrointestinal Investigations With Physical Activity Using Accelerometry.

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT01507298
Enrollment
21
Registered
2012-01-10
Start date
2012-03-31
Completion date
2013-07-31
Last updated
2019-09-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Gastro-oesophageal Reflux Disease

Keywords

Physical activity, Accelerometry, Oesophageal pH, Capsule endoscopy

Brief summary

This is an observational study, which aims to compare the outcomes of ambulatory gastrointestinal investigations with physical activity using accelerometry. An ambulatory study refers to one in which the patient is monitored freely, often outside of the hospital environment. For this the investigators will use a lightweight (7.4g) tri-axial accelerometer worn behind the ear. Hypothesis 1 There is no change in the amount or nature of physical activity taken by patients during ambulatory oesophageal pH monitoring or capsule endoscopy. Hypothesis 2 There is no correlation between physical activity levels and speed of gastrointestinal transit.

Detailed description

For capsule endoscopy, the investigators are interested in how physical activity affects the speed of capsule transit through the GI tract. Capsule endoscopy involves a patient swallowing a pill which contains a camera, in order to image the parts of the bowel that a conventional endoscope cannot reach. A rapid transit may result in insufficient mucosal visualisation, which would reduce the sensitivity of the investigation. For oesophageal pH monitoring, it is essential that the patient behaves as they would normally to produce measurements that represent a standard day. Using accelerometry, the investigators can compare the amount, and nature, of physical activity taken throughout the investigation to that of the preceding day, or week. In addition, further analysis of motion data captured will allow us to correlate specific activities and body orientation with pH readings to get a better insight into the pathophysiology of a patient's condition. The studies will be conducted over 6-9 months in Imperial College Trust's medical outpatient service. All patients undergoing capsule endoscopy or ambulatory oesophageal monitoring will be asked to consider participating. Patients will receive the eAR sensor up to 2 days before their investigation, and will be asked to wear it until the end of their investigation (not whilst sleeping). Capsule endoscopy normally takes less than 12 hours, and pH monitoring takes between 24 and 48 hours. Participation makes no difference to the standard or type of care that they will receive, the sensor data is additional.

Interventions

None listed

Sponsors

Imperial College London
Lead SponsorOTHER

Study design

Observational model
OTHER
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

* Planned 24 hour oesophageal pH monitoring study, or capsule endoscopy

Exclusion criteria

1. Undergone previous capsule endoscopy or ambulatory oesophageal pH test 2. Currently a hospital in-patient 3. Severe mobility disorder (unable to walk or mobilise independently) 4. Age less than 18 or above 65 5. Physically unable to wear eAR sensor (eg. bilateral hearing aids or particularly small ears)

Design outcomes

Primary

MeasureTime frameDescription
Physical Activity Change (%)Difference between baseline (2 days average) and test day (during pH monitoring)The primary outcome measure is amount of physical activity undertaken by participants throughout the study period. Participant motion data will be collected using a tri-axial accelerometer in the eAR sensor. Signal processing methods will be used to produce an activity index in the form of a numerical value, from the raw data. Activity levels were grouped at 1- minute intervals into restful, low, moderate or high intensity activity. Activity levels were calibrated for each participant, classifying activity into quartiles, where the most inactivity was labelled 'Restful', 2nd quartile 'low intensity', 3rd quartile 'moderate intensity' and upper quartile 'high intensity'. This provided a personalised activity profile with which to compare activity during the investigation.

Secondary

MeasureTime frameDescription
Change in Relative Intensity of Daily Activities (%)Difference between baseline (2 days average) and test day (during pH monitoring)Measuring the changes in restful (activity equivalent to sitting), low (activity equivalent to a slow walk), moderate (activity equivalent to a brisk walk) and high intensity activity (activity equivalent to running). Including subject-specific activity intensity quartiles, were calculated and compared.

Countries

United Kingdom

Participant flow

Participants by arm

ArmCount
Capsule Endoscopy
A pill camera used for imaging the small bowel
1
24 Hour Oesophageal pH Study
Patients wore the accelerometer before and during the ambulatory oesophageal pH test for activity levels to be recorded and compared.
20
Total21

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyProtocol Violation06

Baseline characteristics

CharacteristicCapsule Endoscopy24 Hour Oesophageal pH StudyTotal
Age, Continuous35 Years
STANDARD_DEVIATION 0
53 Years
STANDARD_DEVIATION 11
50 Years
STANDARD_DEVIATION 12
Region of Enrollment
United Kingdom
1 participants20 participants21 participants
Sex: Female, Male
Female
0 Participants10 Participants10 Participants
Sex: Female, Male
Male
1 Participants10 Participants11 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 10 / 20
other
Total, other adverse events
0 / 10 / 20
serious
Total, serious adverse events
0 / 10 / 20

Outcome results

Primary

Physical Activity Change (%)

The primary outcome measure is amount of physical activity undertaken by participants throughout the study period. Participant motion data will be collected using a tri-axial accelerometer in the eAR sensor. Signal processing methods will be used to produce an activity index in the form of a numerical value, from the raw data. Activity levels were grouped at 1- minute intervals into restful, low, moderate or high intensity activity. Activity levels were calibrated for each participant, classifying activity into quartiles, where the most inactivity was labelled 'Restful', 2nd quartile 'low intensity', 3rd quartile 'moderate intensity' and upper quartile 'high intensity'. This provided a personalised activity profile with which to compare activity during the investigation.

Time frame: Difference between baseline (2 days average) and test day (during pH monitoring)

Population: Due to significant differences in expected and actual recruitment for the capsule endoscopy arm (i.e. 1 subject), raw data collected were not analysed to produce activity metrics.

ArmMeasureValue (MEAN)Dispersion
24 Hour Oesophageal pH StudyPhysical Activity Change (%)-22 Percentage change in activityStandard Deviation 20
Secondary

Change in Relative Intensity of Daily Activities (%)

Measuring the changes in restful (activity equivalent to sitting), low (activity equivalent to a slow walk), moderate (activity equivalent to a brisk walk) and high intensity activity (activity equivalent to running). Including subject-specific activity intensity quartiles, were calculated and compared.

Time frame: Difference between baseline (2 days average) and test day (during pH monitoring)

Population: Raw data captured for capsule endoscopy group not analysed to produce activity metrics due to insufficient numbers recruited (i.e. 1 subject).

ArmMeasureGroupValue (MEAN)Dispersion
24 Hour Oesophageal pH StudyChange in Relative Intensity of Daily Activities (%)Restful8.5 Percentage change in activityStandard Deviation 17
24 Hour Oesophageal pH StudyChange in Relative Intensity of Daily Activities (%)Low-1 Percentage change in activityStandard Deviation 24
24 Hour Oesophageal pH StudyChange in Relative Intensity of Daily Activities (%)Moderate-1 Percentage change in activityStandard Deviation 24
24 Hour Oesophageal pH StudyChange in Relative Intensity of Daily Activities (%)High-6 Percentage change in activityStandard Deviation 7

Source: ClinicalTrials.gov · Data processed: Mar 8, 2026