Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT03479866 |
Other study ID # |
236407 |
Secondary ID |
|
Status |
Recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
June 4, 2018 |
Est. completion date |
May 4, 2023 |
Study information
Verified date |
February 2021 |
Source |
Guy's and St Thomas' NHS Foundation Trust |
Contact |
Sarah Berry, PhD |
Phone |
020 7848 4088 |
Email |
sarah.e.berry[@]kcl.ac.uk |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
The foods we eat - our diet - can affect whether we develop diseases during our lives, such
as diabetes or heart disease. This is because the amount and types of foods we eat can affect
our weight, and because different foods are metabolised (processed) by the body in different
ways.
Scientists have also found that the bacteria in our guts (the gut microbiome) affects our
metabolism, weight and health and that, together with a person's diet and metabolism, could
be used to predict appetite and how meals affect levels of sugar (glucose) and fats (lipids)
found in blood after eating. If blood sugar and fat are too high too often, there's a greater
chance of developing diseases such as diabetes.
The gut microbiome is different in different people. Only 10-20% of the types of bacteria
found in our guts are found in everyone. This might mean that the best diet to prevent
disease needs matching to a person's gut microbiome and it might be possible to find
personalised foods or diets that will help reduce the chance of developing chronic disease as
well as metabolic syndrome.
The study investigators are recruiting volunteers aged 18 years or over from the TwinsUK
cohort to take part in a study that aims to answer the questions above. The participants will
need to come in for a clinical visit where they will give blood, stool, saliva and urine
samples. The participants will also be given a standardised breakfast and lunch and fitted
with a glucose monitor (Abbott Freestyle Libre-CE marked) to monitor their blood sugar
levels. After the visit, the participants will be asked to eat standardised meals at home for
breakfast for a further 12 days. Participants will also be required to prick their fingers at
regular intervals to collect small amounts of blood, and to record constantly their appetite,
food, physical activity and sleep using apps and wearable devices.
Description:
Choice of design: The study is a single arm mechanistic intervention study.
Study population: Twin participants will be recruited from the TwinsUK database and non-twins
will be recruited via social media platforms and advertising campaigns.
Screening Assessment: Prospective participants will be selected based on the defined
inclusion and exclusion criteria by the study management team. Recruitment will be done over
the phone and via the Internet and emails and prospective participants will be booked in for
their initial appointment to acquire baseline measurements.
Study duration: Each participant will take part in the study for a period of up to 3 weeks.
The PREDICT study will be divided into 3 protocol cohorts, where all participants (n=2,500)
complete a baseline clinical visit as described below. Of this total, Cohort 1 (n=1,150) will
complete a home-based dietary intervention lasting up to 2 weeks (June 2018 - May 2019).
Within this group, 100 participants will complete an additional home-based dietary
intervention lasting up to 3 weeks (February 2019 - May 2019).
Following completion of this first cohort, Cohort 2 (n=900) will complete a similar
home-based dietary intervention lasting up to 2 weeks (June 2019 - May 2023). Within this
cohort, 50 participants will also complete deep cardiometabolic phenotyping at their clinical
visit (September 2019 - February 2020).
Finally, Cohort 3 (n=450) will only complete the baseline clinical visit (June 2019 - May
2023).
Dietary intervention:
On day one (baseline visit) participants will be given standardised meals for breakfast and
lunch. Participants continuing onto the home-based intervention (n=2,050) will receive a
dietary intervention lasting up to 12 days following their clinical visit. Each participant
will be instructed to eat standardised meals for breakfast, which must be their first meal of
the day. On some of these days the participants will also be asked to eat a standardised
lunch meal. Participants are free to eat whatever they wish at all other times, although we
may provide a list of recommended foods. The standardised meals will be provided to all
participants by the study team on the day of the visit. The foods included as part of these
meals will be foods that are commonly consumed and can be made from products sold in UK
supermarkets. Participants will be reassured that the amount of food will be designed to
ensure a stable body weight over the course of the study. Participants will be asked to
consume the entire amount of food indicated for the standardised meals and to record any
left-over food via a digital app for which training will be provided at the start of the
study. For the remaining 2 days post the 12 day dietary intervention period, participants are
free to eat and drink whatever they wish or choose from the list of recommended foods
provided to them. They will be asked to track all meals, snacks and drinks on their digital
app. Participants will also be advised not to change their physical activity patterns during
the course of the study.
After the baseline visit, regular contact will be made with the participants via phone, their
app and text messages for the period of the intervention to encourage compliance and answer
any queries.
Anthropometry: Weight, height, waist and hip circumference, blood pressure, body fat will be
taken using standard procedures, in duplicates by a trained researcher at all face to face
appointments. DXA scans using a Hologic machine will be used to assess body composition in
all participants.
Dietary and Lifestyle: Participants will be asked to complete a simple online baseline
questionnaire plus record daily dietary and activity information using digital apps.
Lifestyle information (such as sleep, exercise and heart rate) will be monitored using
digital wearable devices. Dietary information and psychological data (eg hunger) will be
recorded in a digital mobile phone app. Training in all apps and equipment will be given at
the baseline visit.
Digital devices: Participants will be asked to record daily dietary and activity information
using digital apps and lifestyle information will be monitored using digital wearable
devices. The continuous glucose monitor (Freestyle Libre, CGM) provides continuous glucose
profiles for up to 14 days. The CGM will be inserted on the back of the upper arm at the
baseline visit by a nurse. Subcutaneous interstitial fluid glucose concentrations are
measured every 15 minutes by the CGM, and can be displayed on a remote device when necessary.
The readings will be blinded so that the participant's behaviour is not affected by the
glucose readings. The CGM will be removed at the end of the intervention period. Removal of
the glucose monitor can be performed by the participants at home and detailed instructions on
the removal procedure will be provided to them on day 1 of their visit. A 24-h contact number
will be made available to participants for any inquiries or if any problems arose. Data from
the CGM will be downloaded, and glucose profiles will be evaluated on the basis of data
collected on days 1-14.
Blood samples: Postprandial blood will be collected on day one in the clinic and on
additional days at home using finger-prick blood sampling.
Digital app: Participants will be asked to download an app designed specifically for this
study, which provides diet & activity logging functionality similar to widely used existing
apps such as MyFitnessPal.
Participants will be asked to record and monitor the following information via the digital
app and wearable devices:
- Daily record of foods eaten throughout the day with serving sizes and photographs
- Continuous sleep and physical activity patterns
- Periodical hunger, satiety and appetite ratings
- Psychological feeling of energy and mood
- Daily medication consumption
During their baseline visit day, participants will be assisted with installation and setup
and provided with instructions on how to use the app. The app will be available in versions
for both iOS and Android operating systems, and will support a wide range of mobile phone
models as expected across the participant population. The app will synchronise remotely with
backend database servers, over an encrypted and authenticated API, and will support offline
operation for when patients wish to record an entry without network coverage. This continuous
background synchronization means that it will not be necessary to explicitly download data
from the phone at the end of the study.
A subgroup of participants from Cohort 2 (n=50) who continue onto the home-phase will be
recruited to provide additional cardiometabolic measures, based on previously collected
metabolomic and phenotyping data. This subgroup will undergo an abdominal XMR scan and
cardiovascular tests at their baseline visit, before continuing onto the home-based
intervention.